{"Identifier":"2020MNRAS.498.4605H__Middleditch_et_al._2006_Instance_1","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Middleditch et al. 2006"],"Citation Start End":[[1079,1102]]} {"Identifier":"2020MNRAS.498.4605HGraber,_Andersson_&_Hogg_2017_Instance_1","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Graber, Andersson & Hogg 2017"],"Citation Start End":[[432,461]]} {"Identifier":"2020MNRAS.498.4605HLink_et_al._(1999)_Instance_1","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Link et al. (1999)"],"Citation Start End":[[464,482]]} {"Identifier":"2020MNRAS.498.4605HAndersson_et_al._(2012)_Instance_1","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Andersson et al. (2012)"],"Citation Start End":[[1183,1206]]} {"Identifier":"2020MNRAS.498.4605HAndersson_et_al._(2012)_Instance_2","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Andersson et al. (2012)"],"Citation Start End":[[1735,1758]]} {"Identifier":"2020MNRAS.498.4605HHo_et_al._(2015_Instance_1","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Ho et al. (2015"],"Citation Start End":[[1842,1857]]} {"Identifier":"2020MNRAS.498.4605HSauls,_Chamel_&_Alpar_(2020)_Instance_1","Paragraph":"The mechanism that produces large spin-up glitches such as those seen in the Vela pulsar (Dodson, Lewis & McCulloch 2007; Palfreyman et al. 2018) and PSR J0537−6910 is thought to be a sudden transfer of angular momentum from a rapidly rotating superfluid that permeates the neutron star inner crust to the rest of the star, which is slowing down from electromagnetic radiation braking (Anderson & Itoh 1975; Haskell & Melatos 2015; Graber, Andersson & Hogg 2017). Link et al. (1999) provide strong support for this theory by first showing that the fractional moment of inertia (Isf\/I) of the superfluid angular momentum reservoir is related to a pulsar’s glitch activity via Isf\/I ≥ 2τcAg, where I is total moment of inertia and $\\tau _{\\rm c}=-\\nu \/2\\dot{\\nu }$ is pulsar characteristic age. They then show that the glitch activity of pulsars like Vela gives Isf\/I ≳ 0.01, and this approximately matches the theoretical fractional moment of inertia of a neutron star’s crust Icrust\/I. For PSR J0537−6910, we find 2τcAg = 0.00874, which agrees with that found in previous works (Middleditch et al. 2006; Antonopoulou et al. 2018; Ferdman et al. 2018). More recently, calculations by Andersson et al. (2012) and Chamel (2013) indicate that the above relation is underestimated after accounting for superfluid entrainment and should instead be $I_{\\rm sf}\/I\\ge 2\\tau _{\\rm c}A_{\\rm g}\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}$, where $\\langle m_{\\rm n}^\\ast \\rangle $ and mn are averaged effective neutron mass and neutron mass, respectively (and $\\langle m_{\\rm n}^\\ast \\rangle \/m_{\\rm n}\\approx 4.2$; Chamel 2012), and as a result, the angular momentum required by a glitch is more than the crust can provide. One solution proposed by Andersson et al. (2012) is that the superfluid component in the crust extends into the core. Subsequently, Ho et al. (2015, 2017) show that, by combining a pulsar’s glitch activity with a measurement of true age or surface temperature, one can obtain valuable constraints on properties of the superfluid and even measure the mass of the pulsar; for the Ag and estimated age of PSR J0537−6910, the pulsar’s mass turns out to be much higher than the canonical 1.4M⊙. Very recently, Sauls, Chamel & Alpar (2020) suggest superfluid entrainment may not be as strong as found by Chamel (2012, 2017). More work is needed to resolve the issue.","Citation Text":["Sauls, Chamel & Alpar (2020)"],"Citation Start End":[[2215,2243]]} {"Identifier":"2022MNRAS.514.1169A__Padmanabhan_et_al._2007_Instance_1","Paragraph":"Both our BOSS×BOSS and FIRAS×BOSS models require the dark matter angular power spectrum of the overdensity field, $C_{\\ell }^{\\delta }(z,z^{\\prime })$. We calculate this angular power spectrum with the Boltzmann code CLASS (Di Dio et al. 2013, 2014), using cosmological parameters inferred from the Planck 2015 (Ade et al. 2016) temperature and low-ℓ polarization maps (TT + LowP). The Halofit routine (Smith et al. 2003) provides nonlinear corrections to the power spectrum. However, on the several-degree scales of this analysis, the fluctuations are well-described by linear perturbation theory ($k_{\\rm max} \\sim \\frac{\\ell _{\\rm max}}{\\chi (z)_{\\rm min}} \\sim \\frac{50}{880}$ h\/Mpc ∼0.06 h\/Mpc), and nonlinear corrections are small. CLASS computes the angular power spectrum from the 3D power spectrum, P(k), according to the equation\n(11)$$\\begin{eqnarray*}\r\nC_{\\ell }^{A\\times B}(z,z^{\\prime }) = \\frac{2}{\\pi } \\int k^2 P^{\\delta }(k,z{=}0) W_A^{\\rm tot}(k,z)W_B^{\\rm tot}(k,z^{\\prime }) \\mathrm{d}k,\r\n\\end{eqnarray*}$$where Pδ(k, z = 0) is the dark matter power spectrum at the current epoch, and, if there are no redshift space distortions (RSDs),\n(12)$$\\begin{eqnarray*}\r\nW_A(k, z) = b_A \\int \\phi _z(z^{\\prime \\prime }) G(z^{\\prime \\prime },k) j_{\\ell }[k \\chi (z^{\\prime \\prime })] \\mathrm{d}z^{\\prime \\prime },\r\n\\end{eqnarray*}$$where bA is the bias for dark matter tracer A, ϕz(z″) is a tophat redshift selection function that is non-zero only over the range of the redshift slice centered at redshift z and normalized to integrate to 1, jℓ is a spherical Bessel function of the first kind with parameter ℓ, G(z″, k) is the growth factor, and χ(z″) is the radial comoving distance to the shell at redshift z″. Linear RSDs can be included (Fisher, Scharf & Lahav 1994; Padmanabhan et al. 2007) by replacing WA(k, z) with $W_A^{\\rm tot}(k,z)$, where\n(13)$$\\begin{eqnarray*}\r\nW_A^{\\rm tot}(k, z) &= &W_A(k, z) + W_A^{\\rm RSD}(k,z)\\nonumber \\\\\r\nW_A^{\\rm RSD}(k,z) &=&b_A \\int \\beta _A(z^{\\prime \\prime }) \\phi _z(z^{\\prime \\prime }) \\times \\nonumber \\\\\r\n&& \\biggl \\lbrace \\frac{2\\ell ^2+2\\ell -1}{(2\\ell +3)(2\\ell -1)}j_{\\ell }[k \\chi (z^{\\prime \\prime })]\\nonumber \\\\\r\n& &- \\frac{\\ell (\\ell -1)}{(2\\ell -1)(2\\ell +1)}j_{\\ell -2}[k \\chi (z^{\\prime \\prime })]\\nonumber \\\\\r\n& &- \\frac{(\\ell +1)(\\ell +2)}{(2\\ell +1)(2\\ell +3)}j_{\\ell +2 }[k \\chi (z^{\\prime \\prime })] \\biggr \\rbrace \\mathrm{d}z^{\\prime \\prime },\r\n\\end{eqnarray*}$$where βA(z) = f(z)\/bA, with f(z) being the logarithmic growth rate of linear perturbations in the matter power spectrum. The $C_{\\ell }^{A\\times B}(z,z^{\\prime })$ that results from using $W_A^{\\rm tot}(k, z)$ and $W_B^{\\rm tot}(k, z)$ contains cosmological terms proportional to bAbB, proportional to (bA + bB)\/2, and independent of both bA and bB. We label these terms $C_{\\ell }^{(2)}(z,z^{\\prime })$, $C_{\\ell }^{(1)}(z,z^{\\prime })$, and $C_{\\ell }^{(0)}(z,z^{\\prime })$ respectively. They are calculated from CLASS via linear combinations of Cℓ(z, z′) computations without RSD and bias 1, with RSD and bias 1, and with RSD and bias 0. With this formalism, the cross-power spectrum of two biased matter tracers is given by\n(14)$$\\begin{eqnarray*}\r\nC_{\\ell }^{A\\times B}(z,z^{\\prime }) = b_A b_B C_{\\ell }^{(2)}(z,z^{\\prime }) + \\frac{b_A {+} b_B}{2}C_{\\ell }^{(1)}(z,z^{\\prime }) + C_{\\ell }^{(0)}(z,z^{\\prime }). \\nonumber \\\\\r\n\\end{eqnarray*}$$The bias dependence of these terms is reminiscent of the Kaiser correction in power spectrum space. Indeed, these equations can be derived by including the Kaiser enhancement term in a plane-wave expansion of the power spectrum and integrating along the line-of-sight (Padmanabhan et al. 2007).","Citation Text":["Padmanabhan et al. 2007"],"Citation Start End":[[1783,1806]]} {"Identifier":"2022MNRAS.514.1169A__Padmanabhan_et_al._2007_Instance_2","Paragraph":"Both our BOSS×BOSS and FIRAS×BOSS models require the dark matter angular power spectrum of the overdensity field, $C_{\\ell }^{\\delta }(z,z^{\\prime })$. We calculate this angular power spectrum with the Boltzmann code CLASS (Di Dio et al. 2013, 2014), using cosmological parameters inferred from the Planck 2015 (Ade et al. 2016) temperature and low-ℓ polarization maps (TT + LowP). The Halofit routine (Smith et al. 2003) provides nonlinear corrections to the power spectrum. However, on the several-degree scales of this analysis, the fluctuations are well-described by linear perturbation theory ($k_{\\rm max} \\sim \\frac{\\ell _{\\rm max}}{\\chi (z)_{\\rm min}} \\sim \\frac{50}{880}$ h\/Mpc ∼0.06 h\/Mpc), and nonlinear corrections are small. CLASS computes the angular power spectrum from the 3D power spectrum, P(k), according to the equation\n(11)$$\\begin{eqnarray*}\r\nC_{\\ell }^{A\\times B}(z,z^{\\prime }) = \\frac{2}{\\pi } \\int k^2 P^{\\delta }(k,z{=}0) W_A^{\\rm tot}(k,z)W_B^{\\rm tot}(k,z^{\\prime }) \\mathrm{d}k,\r\n\\end{eqnarray*}$$where Pδ(k, z = 0) is the dark matter power spectrum at the current epoch, and, if there are no redshift space distortions (RSDs),\n(12)$$\\begin{eqnarray*}\r\nW_A(k, z) = b_A \\int \\phi _z(z^{\\prime \\prime }) G(z^{\\prime \\prime },k) j_{\\ell }[k \\chi (z^{\\prime \\prime })] \\mathrm{d}z^{\\prime \\prime },\r\n\\end{eqnarray*}$$where bA is the bias for dark matter tracer A, ϕz(z″) is a tophat redshift selection function that is non-zero only over the range of the redshift slice centered at redshift z and normalized to integrate to 1, jℓ is a spherical Bessel function of the first kind with parameter ℓ, G(z″, k) is the growth factor, and χ(z″) is the radial comoving distance to the shell at redshift z″. Linear RSDs can be included (Fisher, Scharf & Lahav 1994; Padmanabhan et al. 2007) by replacing WA(k, z) with $W_A^{\\rm tot}(k,z)$, where\n(13)$$\\begin{eqnarray*}\r\nW_A^{\\rm tot}(k, z) &= &W_A(k, z) + W_A^{\\rm RSD}(k,z)\\nonumber \\\\\r\nW_A^{\\rm RSD}(k,z) &=&b_A \\int \\beta _A(z^{\\prime \\prime }) \\phi _z(z^{\\prime \\prime }) \\times \\nonumber \\\\\r\n&& \\biggl \\lbrace \\frac{2\\ell ^2+2\\ell -1}{(2\\ell +3)(2\\ell -1)}j_{\\ell }[k \\chi (z^{\\prime \\prime })]\\nonumber \\\\\r\n& &- \\frac{\\ell (\\ell -1)}{(2\\ell -1)(2\\ell +1)}j_{\\ell -2}[k \\chi (z^{\\prime \\prime })]\\nonumber \\\\\r\n& &- \\frac{(\\ell +1)(\\ell +2)}{(2\\ell +1)(2\\ell +3)}j_{\\ell +2 }[k \\chi (z^{\\prime \\prime })] \\biggr \\rbrace \\mathrm{d}z^{\\prime \\prime },\r\n\\end{eqnarray*}$$where βA(z) = f(z)\/bA, with f(z) being the logarithmic growth rate of linear perturbations in the matter power spectrum. The $C_{\\ell }^{A\\times B}(z,z^{\\prime })$ that results from using $W_A^{\\rm tot}(k, z)$ and $W_B^{\\rm tot}(k, z)$ contains cosmological terms proportional to bAbB, proportional to (bA + bB)\/2, and independent of both bA and bB. We label these terms $C_{\\ell }^{(2)}(z,z^{\\prime })$, $C_{\\ell }^{(1)}(z,z^{\\prime })$, and $C_{\\ell }^{(0)}(z,z^{\\prime })$ respectively. They are calculated from CLASS via linear combinations of Cℓ(z, z′) computations without RSD and bias 1, with RSD and bias 1, and with RSD and bias 0. With this formalism, the cross-power spectrum of two biased matter tracers is given by\n(14)$$\\begin{eqnarray*}\r\nC_{\\ell }^{A\\times B}(z,z^{\\prime }) = b_A b_B C_{\\ell }^{(2)}(z,z^{\\prime }) + \\frac{b_A {+} b_B}{2}C_{\\ell }^{(1)}(z,z^{\\prime }) + C_{\\ell }^{(0)}(z,z^{\\prime }). \\nonumber \\\\\r\n\\end{eqnarray*}$$The bias dependence of these terms is reminiscent of the Kaiser correction in power spectrum space. Indeed, these equations can be derived by including the Kaiser enhancement term in a plane-wave expansion of the power spectrum and integrating along the line-of-sight (Padmanabhan et al. 2007).","Citation Text":["Padmanabhan et al. 2007"],"Citation Start End":[[3699,3722]]} {"Identifier":"2015ApJ...806..184D__Schlickeiser_2010_Instance_1","Paragraph":"We can even further extend this analysis and constrain cosmic-ray acceleration efficiency. Using accretion shock models like Pavlidou & Fields (2006), we can estimate particle acceleration energy efficiency by comparing the kinetic power of accreted gas that follows from the model, with the power that goes into SFCR particles that is constrained by the detected neutrino and gamma-ray fluxes. For example, if we assume that SFCRs are dominantly accelerated in shocks that produce gamma-ray and neutrino spectra with index α = 2.2 (corresponding to Mach number ∼5; Bell 1978; Schlickeiser 2010), then from using the latest observed neutrino flux (with index αν = 2.46) as the upper limit, it follows that the energy efficiency of accelerating cosmic rays at these structures in the energy range 1 GeV–1 TeV is ∼40%, that is, we find that ∼40% of energy that goes into shocks gets converted into accelerated particles. This is a slightly higher efficiency compared to results from numerical models of nonlinear diffusive shock acceleration of, for example, Kang & Ryu (2013), who found that shocks of similar strength result in ≳10% acceleration energy efficiency. If, on the other hand, we consider spectral index α = 2 to represent the SFCR spectra (corresponding to Mach number ∼10) and use that to find the upper limit of SFCR flux as maximally allowed by the observed EGRB and neutrino flux with index αν = 2, we find that in this case cosmic-ray acceleration energy efficiency is 1%. This efficiency is about an order of magnitude lower compared to results from the numerical model of Kang & Ryu (2013), who found that shocks of similar strength result in an efficiency of ∼20%. Such extreme changes in efficiency that follow from our analysis are, of course, due to the fact that our constraint comes from the high-energy end that is fixed by observed neutrino fluxes, while most energy in cosmic rays comes from the low-energy end due to the power-law spectra.","Citation Text":["Schlickeiser 2010"],"Citation Start End":[[577,594]]} {"Identifier":"2015ApJ...806..184DKang_&_Ryu_(2013)_Instance_1","Paragraph":"We can even further extend this analysis and constrain cosmic-ray acceleration efficiency. Using accretion shock models like Pavlidou & Fields (2006), we can estimate particle acceleration energy efficiency by comparing the kinetic power of accreted gas that follows from the model, with the power that goes into SFCR particles that is constrained by the detected neutrino and gamma-ray fluxes. For example, if we assume that SFCRs are dominantly accelerated in shocks that produce gamma-ray and neutrino spectra with index α = 2.2 (corresponding to Mach number ∼5; Bell 1978; Schlickeiser 2010), then from using the latest observed neutrino flux (with index αν = 2.46) as the upper limit, it follows that the energy efficiency of accelerating cosmic rays at these structures in the energy range 1 GeV–1 TeV is ∼40%, that is, we find that ∼40% of energy that goes into shocks gets converted into accelerated particles. This is a slightly higher efficiency compared to results from numerical models of nonlinear diffusive shock acceleration of, for example, Kang & Ryu (2013), who found that shocks of similar strength result in ≳10% acceleration energy efficiency. If, on the other hand, we consider spectral index α = 2 to represent the SFCR spectra (corresponding to Mach number ∼10) and use that to find the upper limit of SFCR flux as maximally allowed by the observed EGRB and neutrino flux with index αν = 2, we find that in this case cosmic-ray acceleration energy efficiency is 1%. This efficiency is about an order of magnitude lower compared to results from the numerical model of Kang & Ryu (2013), who found that shocks of similar strength result in an efficiency of ∼20%. Such extreme changes in efficiency that follow from our analysis are, of course, due to the fact that our constraint comes from the high-energy end that is fixed by observed neutrino fluxes, while most energy in cosmic rays comes from the low-energy end due to the power-law spectra.","Citation Text":["Kang & Ryu (2013)"],"Citation Start End":[[1057,1074]]} {"Identifier":"2015ApJ...806..184DKang_&_Ryu_(2013)_Instance_2","Paragraph":"We can even further extend this analysis and constrain cosmic-ray acceleration efficiency. Using accretion shock models like Pavlidou & Fields (2006), we can estimate particle acceleration energy efficiency by comparing the kinetic power of accreted gas that follows from the model, with the power that goes into SFCR particles that is constrained by the detected neutrino and gamma-ray fluxes. For example, if we assume that SFCRs are dominantly accelerated in shocks that produce gamma-ray and neutrino spectra with index α = 2.2 (corresponding to Mach number ∼5; Bell 1978; Schlickeiser 2010), then from using the latest observed neutrino flux (with index αν = 2.46) as the upper limit, it follows that the energy efficiency of accelerating cosmic rays at these structures in the energy range 1 GeV–1 TeV is ∼40%, that is, we find that ∼40% of energy that goes into shocks gets converted into accelerated particles. This is a slightly higher efficiency compared to results from numerical models of nonlinear diffusive shock acceleration of, for example, Kang & Ryu (2013), who found that shocks of similar strength result in ≳10% acceleration energy efficiency. If, on the other hand, we consider spectral index α = 2 to represent the SFCR spectra (corresponding to Mach number ∼10) and use that to find the upper limit of SFCR flux as maximally allowed by the observed EGRB and neutrino flux with index αν = 2, we find that in this case cosmic-ray acceleration energy efficiency is 1%. This efficiency is about an order of magnitude lower compared to results from the numerical model of Kang & Ryu (2013), who found that shocks of similar strength result in an efficiency of ∼20%. Such extreme changes in efficiency that follow from our analysis are, of course, due to the fact that our constraint comes from the high-energy end that is fixed by observed neutrino fluxes, while most energy in cosmic rays comes from the low-energy end due to the power-law spectra.","Citation Text":["Kang & Ryu (2013)"],"Citation Start End":[[1592,1609]]} {"Identifier":"2019MNRAS.487.2474C__Sharma_et_al._2018_Instance_1","Paragraph":"In this work, we analyse a set of high-resolution stellar spectra that were acquired by the High Efficiency and Resolution Multi-Element Spectrograph (HERMES; Barden et al. 2010; Sheinis et al. 2015), a multifibre spectrograph mounted on the 3.9-metre Anglo-Australian Telescope (AAT). The spectrograph has a resolving power of R ${\\sim } 28\\, 000$ and covers four wavelength ranges (4713–4903, 5648–5873, 6478–6737, and 7585–7887 Å), frequently also referred to as ‘spectral arms’. Observations used in this study have been taken from multiple observing programmes that make use of the HERMES spectrograph: the main GALAH survey (De Silva et al. 2015), the K2-HERMES survey (Wittenmyer et al. 2018), and the TESS-HERMES survey (Sharma et al. 2018). Those observing programmes mostly observe stars at higher Galactic latitudes (|b| > 10°) and employ different selection functions, but share the same observing procedures, reduction, and analysis pipeline (internal version 5.3; Kos et al. 2017). All three programmes are magnitude-limited, with no colour cuts (except the K2-HERMES survey), and observations predominantly fall in the V magnitude range between 12 and 14. This leads to an unbiased sample of mostly southern stars that can be used for different population studies, such as multiple stellar systems in our case. Additionally, stellar atmospheric parameters and individual abundances derived from spectra acquired during different observing programmes are analysed with the same The Cannon procedure (internal version 182112 that uses parallax information to infer log g of a star; Ness et al. 2015; Buder et al. 2018), so they are intercomparable. The Cannon is a data-driven interpolation approach trained on a set of stellar spectra that span the majority of the stellar parameter space (for details, see Buder et al. 2018). Whenever we refer to valid or unflagged stellar parameters in the text, only stars with the quality flag flag_cannon equal to 0 were selected.","Citation Text":["Sharma et al. 2018"],"Citation Start End":[[729,747]]} {"Identifier":"2019MNRAS.487.2474CBarden_et_al._2010_Instance_1","Paragraph":"In this work, we analyse a set of high-resolution stellar spectra that were acquired by the High Efficiency and Resolution Multi-Element Spectrograph (HERMES; Barden et al. 2010; Sheinis et al. 2015), a multifibre spectrograph mounted on the 3.9-metre Anglo-Australian Telescope (AAT). The spectrograph has a resolving power of R ${\\sim } 28\\, 000$ and covers four wavelength ranges (4713–4903, 5648–5873, 6478–6737, and 7585–7887 Å), frequently also referred to as ‘spectral arms’. Observations used in this study have been taken from multiple observing programmes that make use of the HERMES spectrograph: the main GALAH survey (De Silva et al. 2015), the K2-HERMES survey (Wittenmyer et al. 2018), and the TESS-HERMES survey (Sharma et al. 2018). Those observing programmes mostly observe stars at higher Galactic latitudes (|b| > 10°) and employ different selection functions, but share the same observing procedures, reduction, and analysis pipeline (internal version 5.3; Kos et al. 2017). All three programmes are magnitude-limited, with no colour cuts (except the K2-HERMES survey), and observations predominantly fall in the V magnitude range between 12 and 14. This leads to an unbiased sample of mostly southern stars that can be used for different population studies, such as multiple stellar systems in our case. Additionally, stellar atmospheric parameters and individual abundances derived from spectra acquired during different observing programmes are analysed with the same The Cannon procedure (internal version 182112 that uses parallax information to infer log g of a star; Ness et al. 2015; Buder et al. 2018), so they are intercomparable. The Cannon is a data-driven interpolation approach trained on a set of stellar spectra that span the majority of the stellar parameter space (for details, see Buder et al. 2018). Whenever we refer to valid or unflagged stellar parameters in the text, only stars with the quality flag flag_cannon equal to 0 were selected.","Citation Text":["Barden et al. 2010"],"Citation Start End":[[159,177]]} {"Identifier":"2019MNRAS.487.2474CBuder_et_al._2018_Instance_2","Paragraph":"In this work, we analyse a set of high-resolution stellar spectra that were acquired by the High Efficiency and Resolution Multi-Element Spectrograph (HERMES; Barden et al. 2010; Sheinis et al. 2015), a multifibre spectrograph mounted on the 3.9-metre Anglo-Australian Telescope (AAT). The spectrograph has a resolving power of R ${\\sim } 28\\, 000$ and covers four wavelength ranges (4713–4903, 5648–5873, 6478–6737, and 7585–7887 Å), frequently also referred to as ‘spectral arms’. Observations used in this study have been taken from multiple observing programmes that make use of the HERMES spectrograph: the main GALAH survey (De Silva et al. 2015), the K2-HERMES survey (Wittenmyer et al. 2018), and the TESS-HERMES survey (Sharma et al. 2018). Those observing programmes mostly observe stars at higher Galactic latitudes (|b| > 10°) and employ different selection functions, but share the same observing procedures, reduction, and analysis pipeline (internal version 5.3; Kos et al. 2017). All three programmes are magnitude-limited, with no colour cuts (except the K2-HERMES survey), and observations predominantly fall in the V magnitude range between 12 and 14. This leads to an unbiased sample of mostly southern stars that can be used for different population studies, such as multiple stellar systems in our case. Additionally, stellar atmospheric parameters and individual abundances derived from spectra acquired during different observing programmes are analysed with the same The Cannon procedure (internal version 182112 that uses parallax information to infer log g of a star; Ness et al. 2015; Buder et al. 2018), so they are intercomparable. The Cannon is a data-driven interpolation approach trained on a set of stellar spectra that span the majority of the stellar parameter space (for details, see Buder et al. 2018). Whenever we refer to valid or unflagged stellar parameters in the text, only stars with the quality flag flag_cannon equal to 0 were selected.","Citation Text":["Buder et al. 2018"],"Citation Start End":[[1821,1838]]} {"Identifier":"2019MNRAS.487.2474CBuder_et_al._2018_Instance_1","Paragraph":"In this work, we analyse a set of high-resolution stellar spectra that were acquired by the High Efficiency and Resolution Multi-Element Spectrograph (HERMES; Barden et al. 2010; Sheinis et al. 2015), a multifibre spectrograph mounted on the 3.9-metre Anglo-Australian Telescope (AAT). The spectrograph has a resolving power of R ${\\sim } 28\\, 000$ and covers four wavelength ranges (4713–4903, 5648–5873, 6478–6737, and 7585–7887 Å), frequently also referred to as ‘spectral arms’. Observations used in this study have been taken from multiple observing programmes that make use of the HERMES spectrograph: the main GALAH survey (De Silva et al. 2015), the K2-HERMES survey (Wittenmyer et al. 2018), and the TESS-HERMES survey (Sharma et al. 2018). Those observing programmes mostly observe stars at higher Galactic latitudes (|b| > 10°) and employ different selection functions, but share the same observing procedures, reduction, and analysis pipeline (internal version 5.3; Kos et al. 2017). All three programmes are magnitude-limited, with no colour cuts (except the K2-HERMES survey), and observations predominantly fall in the V magnitude range between 12 and 14. This leads to an unbiased sample of mostly southern stars that can be used for different population studies, such as multiple stellar systems in our case. Additionally, stellar atmospheric parameters and individual abundances derived from spectra acquired during different observing programmes are analysed with the same The Cannon procedure (internal version 182112 that uses parallax information to infer log g of a star; Ness et al. 2015; Buder et al. 2018), so they are intercomparable. The Cannon is a data-driven interpolation approach trained on a set of stellar spectra that span the majority of the stellar parameter space (for details, see Buder et al. 2018). Whenever we refer to valid or unflagged stellar parameters in the text, only stars with the quality flag flag_cannon equal to 0 were selected.","Citation Text":["Buder et al. 2018"],"Citation Start End":[[1613,1630]]} {"Identifier":"2022ApJ...940L..13A__Chen_et_al._2020_Instance_1","Paragraph":"Since 2018 the Parker Solar Probe (PSP) mission is collecting solar wind plasma and magnetic field data through the inner heliosphere, reaching the closest distance to the Sun ever reached by any previous mission (Fox et al. 2016; Kasper et al. 2021). Thanks to the PSP journey around the Sun (it has completed 11 orbits) a different picture has been drawn for the near-Sun solar wind with respect to the near-Earth one (Bale et al. 2019; Kasper et al. 2019; Chhiber et al. 2020; Malaspina et al. 2020; Bandyopadhyay et al. 2022; Zank et al. 2022). Different near-Sun phenomena have been frequently encountered, with the emergence of magnetic field flips, i.e., the so-called switchbacks (Dudok de Wit et al. 2020; Zank et al. 2020), kinetic-scale current sheets (Lotekar et al. 2022), and a scale-invariant population of current sheets between ion and electron inertial scales (Chhiber et al. 2021). Going away from the Sun (from 0.17 to 0.8 au), evidence of radial evolution of different properties of solar wind turbulence (Chen et al. 2020) as the spectral slope of the inertial range (from −3\/2 close to the Sun to −5\/3, at distances larger than 0.4 au), an increase of the outer scale of turbulence, a decrease of the Alfvénic flux, and a decrease of the imbalance between outward (z\n+) and inward (z\n−) propagating components (Chen et al. 2020) has been provided. Although the near-Sun solar wind shares different properties with the near-Earth one (Allen et al. 2020; Cuesta et al. 2022), significant differences have been also found in the variance of magnetic fluctuations (about 2 orders of magnitude) and in the compressive component of inertial range turbulence. In a similar way, Alberti et al. (2020) first reported a breakdown of the scaling properties of the energy transfer rate, likely related to the breaking of the phase-coherence of inertial range fluctuations. These findings, also highlighted by Telloni et al. (2021) and Alberti et al. (2022) analyzing a radial alignment between PSP and Solar Orbiter, and PSP and BepiColombo, respectively, have been interpreted as an increase in the efficiency of the nonlinear energy cascade mechanism when moving away from the Sun. More recently, by investigating the helical content of turbulence Alberti et al. (2022) highlighted a damping of magnetic helicity over the inertial range between 0.17 and 0.6 au suggesting that the solar wind develops into turbulence by a concurrent effect of large-scale convection of helicity and creation\/annihilation of helical wave structures. All these features shed new light onto the radial evolution of solar wind turbulence that urges to be considered in expanding models of the solar wind (Verdini et al. 2019; Grappin et al. 2021), and also to reproduce and investigate the role of proton heating and anisotropy of magnetic field fluctuations (Hellinger et al. 2015).","Citation Text":["Chen et al. 2020"],"Citation Start End":[[1027,1043]]} {"Identifier":"2022ApJ...940L..13A__Chen_et_al._2020_Instance_2","Paragraph":"Since 2018 the Parker Solar Probe (PSP) mission is collecting solar wind plasma and magnetic field data through the inner heliosphere, reaching the closest distance to the Sun ever reached by any previous mission (Fox et al. 2016; Kasper et al. 2021). Thanks to the PSP journey around the Sun (it has completed 11 orbits) a different picture has been drawn for the near-Sun solar wind with respect to the near-Earth one (Bale et al. 2019; Kasper et al. 2019; Chhiber et al. 2020; Malaspina et al. 2020; Bandyopadhyay et al. 2022; Zank et al. 2022). Different near-Sun phenomena have been frequently encountered, with the emergence of magnetic field flips, i.e., the so-called switchbacks (Dudok de Wit et al. 2020; Zank et al. 2020), kinetic-scale current sheets (Lotekar et al. 2022), and a scale-invariant population of current sheets between ion and electron inertial scales (Chhiber et al. 2021). Going away from the Sun (from 0.17 to 0.8 au), evidence of radial evolution of different properties of solar wind turbulence (Chen et al. 2020) as the spectral slope of the inertial range (from −3\/2 close to the Sun to −5\/3, at distances larger than 0.4 au), an increase of the outer scale of turbulence, a decrease of the Alfvénic flux, and a decrease of the imbalance between outward (z\n+) and inward (z\n−) propagating components (Chen et al. 2020) has been provided. Although the near-Sun solar wind shares different properties with the near-Earth one (Allen et al. 2020; Cuesta et al. 2022), significant differences have been also found in the variance of magnetic fluctuations (about 2 orders of magnitude) and in the compressive component of inertial range turbulence. In a similar way, Alberti et al. (2020) first reported a breakdown of the scaling properties of the energy transfer rate, likely related to the breaking of the phase-coherence of inertial range fluctuations. These findings, also highlighted by Telloni et al. (2021) and Alberti et al. (2022) analyzing a radial alignment between PSP and Solar Orbiter, and PSP and BepiColombo, respectively, have been interpreted as an increase in the efficiency of the nonlinear energy cascade mechanism when moving away from the Sun. More recently, by investigating the helical content of turbulence Alberti et al. (2022) highlighted a damping of magnetic helicity over the inertial range between 0.17 and 0.6 au suggesting that the solar wind develops into turbulence by a concurrent effect of large-scale convection of helicity and creation\/annihilation of helical wave structures. All these features shed new light onto the radial evolution of solar wind turbulence that urges to be considered in expanding models of the solar wind (Verdini et al. 2019; Grappin et al. 2021), and also to reproduce and investigate the role of proton heating and anisotropy of magnetic field fluctuations (Hellinger et al. 2015).","Citation Text":["Chen et al. 2020"],"Citation Start End":[[1334,1350]]} {"Identifier":"2016MNRAS.455.2131L__Liu_&_Wei_2014_Instance_1","Paragraph":"As we have shown that the Ep–Eγ relation does not significantly evolve with redshift, we can use it to calibrate GRBs. To avoid the circularity problem, the Padé method proposed by Liu & Wei (2014) is applied. The main calibrating procedures are as follows: First, derive the distance-redshift relation of SNe Ia [here we use the Union2.1 (Suzuki et al. 2012) data set] using the Padé approximation of order (3,2), i.e.\n\n(17)\n\n\\begin{equation}\n\\mu (z)=\\frac{\\alpha _0+\\alpha _1z+\\alpha _2z^2+\\alpha _3z^3}{1+\\beta _1z+\\beta _2z^2},\n\\end{equation}\n\nwhere the coefficients (α0, α1, α2, α3, β1, β2) and the corresponding covariance matrix are derived by fitting equation (17) to the Union2.1 data set (see Liu & Wei 2014 for details). Assuming that the low-z GRBs trace the same Hubble diagram to SNe Ia, we can calculate the distance moduli of low-z GRBs directly from equation (17). The uncertainty of μ propagates from the uncertainties of the coefficients (αi, βi). Then the luminosity distance of low-z GRBs can be obtained using the relation\n\n(18)\n\n\\begin{equation}\n\\mu (z)=5\\log \\frac{d_L(z)}{\\rm {Mpc}}+25.\n\\end{equation}\n\nAs dL is known, the collimation-corrected energy can be further calculated from equation (11). Note that there are only 12 low-z GRBs and 12 high-z GRBs available since the others have no measurement of jet opening angle. Then we fit the Ep–Eγ relation (i.e. equation (5)) to the 12 low-z GRBs, which gives the best-fitting parameters\n\n(19)\n\n\\begin{eqnarray}\n\\sigma _{\\rm int}=0.161\\pm 0.059,\\ \\ a=50.632\\pm 0.062,\\ \\ b=1.537\\pm 0.145.\\nonumber\\\\\n\\end{eqnarray}\n\nBy directly extrapolating the Ep–Eγ relation to high-z GRBs, we can inversely obtain the collimation-corrected energy for 12 high-z GRBs from equation (5). Finally, calculate the luminosity distance of high-z GRBs from equation (11), and then the distance moduli from equation (18). The uncertainty of distance moduli propagates from the uncertainties of Eγ, Sbolo and Fbeam, i.e. (Schaefer 2007),\n\n(20)\n\n\\begin{equation}\n\\sigma _{\\mu }^2=\\left(\\frac{5}{2\\ln 10}\\right)^2\\left[(\\ln 10)^2\\sigma _{\\log E_{\\gamma }}^2 + \\frac{\\sigma _{S_{\\rm bolo}}^2}{S_{\\rm bolo}^2} + \\frac{\\sigma _{F_{\\rm beam}}^2}{F_{\\rm beam}^2}\\right],\n\\end{equation}\n\nwhere\n\n(21)\n\n\\begin{eqnarray}\n\\sigma _{\\log E_{\\gamma }}^2=\\sigma _a^2 + \\left(\\sigma _b\\log \\frac{E_{p,i}}{300\\ {\\rm keV}}\\right)^2 + \\left(\\frac{b}{\\ln 10}\\frac{\\sigma _{E_{p,i}}}{E_{p,i}}\\right)^2 + \\sigma _{\\rm int}^2.\\nonumber\\\\\n\\end{eqnarray}\n\n","Citation Text":["Liu & Wei (2014)"],"Citation Start End":[[181,197]]} {"Identifier":"2016MNRAS.455.2131L__Liu_&_Wei_2014_Instance_2","Paragraph":"As we have shown that the Ep–Eγ relation does not significantly evolve with redshift, we can use it to calibrate GRBs. To avoid the circularity problem, the Padé method proposed by Liu & Wei (2014) is applied. The main calibrating procedures are as follows: First, derive the distance-redshift relation of SNe Ia [here we use the Union2.1 (Suzuki et al. 2012) data set] using the Padé approximation of order (3,2), i.e.\n\n(17)\n\n\\begin{equation}\n\\mu (z)=\\frac{\\alpha _0+\\alpha _1z+\\alpha _2z^2+\\alpha _3z^3}{1+\\beta _1z+\\beta _2z^2},\n\\end{equation}\n\nwhere the coefficients (α0, α1, α2, α3, β1, β2) and the corresponding covariance matrix are derived by fitting equation (17) to the Union2.1 data set (see Liu & Wei 2014 for details). Assuming that the low-z GRBs trace the same Hubble diagram to SNe Ia, we can calculate the distance moduli of low-z GRBs directly from equation (17). The uncertainty of μ propagates from the uncertainties of the coefficients (αi, βi). Then the luminosity distance of low-z GRBs can be obtained using the relation\n\n(18)\n\n\\begin{equation}\n\\mu (z)=5\\log \\frac{d_L(z)}{\\rm {Mpc}}+25.\n\\end{equation}\n\nAs dL is known, the collimation-corrected energy can be further calculated from equation (11). Note that there are only 12 low-z GRBs and 12 high-z GRBs available since the others have no measurement of jet opening angle. Then we fit the Ep–Eγ relation (i.e. equation (5)) to the 12 low-z GRBs, which gives the best-fitting parameters\n\n(19)\n\n\\begin{eqnarray}\n\\sigma _{\\rm int}=0.161\\pm 0.059,\\ \\ a=50.632\\pm 0.062,\\ \\ b=1.537\\pm 0.145.\\nonumber\\\\\n\\end{eqnarray}\n\nBy directly extrapolating the Ep–Eγ relation to high-z GRBs, we can inversely obtain the collimation-corrected energy for 12 high-z GRBs from equation (5). Finally, calculate the luminosity distance of high-z GRBs from equation (11), and then the distance moduli from equation (18). The uncertainty of distance moduli propagates from the uncertainties of Eγ, Sbolo and Fbeam, i.e. (Schaefer 2007),\n\n(20)\n\n\\begin{equation}\n\\sigma _{\\mu }^2=\\left(\\frac{5}{2\\ln 10}\\right)^2\\left[(\\ln 10)^2\\sigma _{\\log E_{\\gamma }}^2 + \\frac{\\sigma _{S_{\\rm bolo}}^2}{S_{\\rm bolo}^2} + \\frac{\\sigma _{F_{\\rm beam}}^2}{F_{\\rm beam}^2}\\right],\n\\end{equation}\n\nwhere\n\n(21)\n\n\\begin{eqnarray}\n\\sigma _{\\log E_{\\gamma }}^2=\\sigma _a^2 + \\left(\\sigma _b\\log \\frac{E_{p,i}}{300\\ {\\rm keV}}\\right)^2 + \\left(\\frac{b}{\\ln 10}\\frac{\\sigma _{E_{p,i}}}{E_{p,i}}\\right)^2 + \\sigma _{\\rm int}^2.\\nonumber\\\\\n\\end{eqnarray}\n\n","Citation Text":["Liu & Wei 2014"],"Citation Start End":[[703,717]]} {"Identifier":"2021MNRAS.500.4004D__Truong_et_al._2020_Instance_1","Paragraph":"Several outcomes from the IllustrisTNG simulations have validated the model against observational constraints, making them suitable for the tasks at hand. Among them we highlight: the shape and width of the red sequence and the blue cloud of z = 0 galaxies (Nelson et al. 2018a), the existence and locus of the star formation main sequence (MS) at low redshifts (Donnari et al. 2019), the distribution of stellar mass across galaxy populations at z ≲ 4 (Pillepich et al. 2018), the galaxy size–mass relation for star-forming and quiescent galaxies at 0 ≤ z ≤ 2 (Genel et al. 2018), the evolution of the galaxy mass–metallicity relation (Torrey et al. 2018), and quantitatively consistent optical morphologies in comparison to Pan-STARRS data (Rodriguez-Gomez et al. 2019) as far as galaxy properties are concerned. These come in addition to observationally-consistent results in relation to the properties of massive hosts and their intra-halo gas: e.g. the X-ray signals of the hot gaseous atmospheres (Davies et al. 2020; Truong et al. 2020), the amount and distribution of highly ionized Oxygen around galaxies (Nelson et al. 2018b), and the distributions of metals in the ICM at low redshifts (Vogelsberger et al. 2018). Importantly, the new physical mechanisms included in the TNG model have been shown to return galaxy populations whose star formation activity is in better agreement with observations than previous calculations like Illustris (Genel et al. 2014; Vogelsberger et al. 2014; Sijacki et al. 2015), in galaxy colours (Weinberger et al. 2018; Nelson et al. 2018a), atomic and molecular gas content of satellite galaxies (Stevens et al. 2019), and quenched fractions of central and satellite galaxies taken together with no distinction (z ≲ 2; Donnari et al. 2019). In a companion paper (Donnari et al. 2020), we discuss in detail the level of agreement between TNG results and observations when centrals and group and cluster satellites are considered separately and show that the quenched fractions of TNG galaxies are overall consistent with observational constraints and hence the results of this paper trustworthy.","Citation Text":["Truong et al. 2020"],"Citation Start End":[[1024,1042]]} {"Identifier":"2021MNRAS.500.4004DDonnari_et_al._2020_Instance_1","Paragraph":"Several outcomes from the IllustrisTNG simulations have validated the model against observational constraints, making them suitable for the tasks at hand. Among them we highlight: the shape and width of the red sequence and the blue cloud of z = 0 galaxies (Nelson et al. 2018a), the existence and locus of the star formation main sequence (MS) at low redshifts (Donnari et al. 2019), the distribution of stellar mass across galaxy populations at z ≲ 4 (Pillepich et al. 2018), the galaxy size–mass relation for star-forming and quiescent galaxies at 0 ≤ z ≤ 2 (Genel et al. 2018), the evolution of the galaxy mass–metallicity relation (Torrey et al. 2018), and quantitatively consistent optical morphologies in comparison to Pan-STARRS data (Rodriguez-Gomez et al. 2019) as far as galaxy properties are concerned. These come in addition to observationally-consistent results in relation to the properties of massive hosts and their intra-halo gas: e.g. the X-ray signals of the hot gaseous atmospheres (Davies et al. 2020; Truong et al. 2020), the amount and distribution of highly ionized Oxygen around galaxies (Nelson et al. 2018b), and the distributions of metals in the ICM at low redshifts (Vogelsberger et al. 2018). Importantly, the new physical mechanisms included in the TNG model have been shown to return galaxy populations whose star formation activity is in better agreement with observations than previous calculations like Illustris (Genel et al. 2014; Vogelsberger et al. 2014; Sijacki et al. 2015), in galaxy colours (Weinberger et al. 2018; Nelson et al. 2018a), atomic and molecular gas content of satellite galaxies (Stevens et al. 2019), and quenched fractions of central and satellite galaxies taken together with no distinction (z ≲ 2; Donnari et al. 2019). In a companion paper (Donnari et al. 2020), we discuss in detail the level of agreement between TNG results and observations when centrals and group and cluster satellites are considered separately and show that the quenched fractions of TNG galaxies are overall consistent with observational constraints and hence the results of this paper trustworthy.","Citation Text":["Donnari et al. 2020"],"Citation Start End":[[1805,1824]]} {"Identifier":"2021MNRAS.502.2922H__Hayward_et_al._2011_Instance_1","Paragraph":"As discussed in Section 1, to identify SMGs in the simulation, it is ideal to compute individual simulated galaxies’ submm flux densities via dust radiative transfer. The mass and spatial resolution of Illustris and IllustrisTNG are insufficient to resolve the subkpc structure of the ISM, and owing to both the subgrid equation-of-state treatment of stellar feedback and resolution, such simulations tend to feature overly puffy discs and thus underestimate the attenuation (Trayford et al. 2017). Consequently, we do not perform radiative transfer directly. Instead, we use the following relation based on the results of performing radiative transfer on higher resolution hydrodynamical simulations of idealized isolated discs and mergers (Hayward et al. 2011, 2013a):\n(1)$$\\begin{eqnarray*}\r\n\\frac{S_{850}}{\\left(\\text{mJy}\\right)} = 0.81 \\left(\\frac{\\text{SFR}}{100 \\, \\left(\\text{M}_\\odot \\, \\text{yr}^{-1}\\right)} \\right)^{0.43} \\left(\\frac{M_{\\rm dust}}{10^8 \\, \\left(\\text{M}_\\odot \\right)} \\right)^{0.54},\r\n\\end{eqnarray*}$$where SFR is the ‘instantaneous’ SFR associated with the star-forming gas cells (for consistency with Hayward et al. 2011) and Mdust is the dust mass. When applying the relation, following Hayward et al. (2013b), we incorporate a scatter of 0.13 dex (independent of SFR and dust mass) assuming a Gaussian distribution (Hayward et al. 2011). The submm flux densities predicted using this relation also agree well with the results of performing dust radiative transfer directly on cosmological zoom simulations (Liang et al. 2018; Cochrane et al. 2019) and a semi-analytical model ( Benson, private communication). Moreover, by combining the above with the observed SFR–M⋆ and Mdust(M⋆, z) relations, one can derive an S850–M⋆ relation (Hayward 2012; Hayward et al. 2013a) that agrees reasonably well with that observed for SMGs (Davies et al. 2013). Although given sufficient resolution and unlimited computing time, it would be preferred to perform radiative transfer directly, our approach has the advantage of trivial computational expense, and it may actually be more accurate than direct radiative transfer given the resolution of state-of-the-art large-volume simulations such as Illustris and IllustrisTNG .","Citation Text":["Hayward et al. 2011"],"Citation Start End":[[742,761]]} {"Identifier":"2021MNRAS.502.2922H__Hayward_et_al._2011_Instance_2","Paragraph":"As discussed in Section 1, to identify SMGs in the simulation, it is ideal to compute individual simulated galaxies’ submm flux densities via dust radiative transfer. The mass and spatial resolution of Illustris and IllustrisTNG are insufficient to resolve the subkpc structure of the ISM, and owing to both the subgrid equation-of-state treatment of stellar feedback and resolution, such simulations tend to feature overly puffy discs and thus underestimate the attenuation (Trayford et al. 2017). Consequently, we do not perform radiative transfer directly. Instead, we use the following relation based on the results of performing radiative transfer on higher resolution hydrodynamical simulations of idealized isolated discs and mergers (Hayward et al. 2011, 2013a):\n(1)$$\\begin{eqnarray*}\r\n\\frac{S_{850}}{\\left(\\text{mJy}\\right)} = 0.81 \\left(\\frac{\\text{SFR}}{100 \\, \\left(\\text{M}_\\odot \\, \\text{yr}^{-1}\\right)} \\right)^{0.43} \\left(\\frac{M_{\\rm dust}}{10^8 \\, \\left(\\text{M}_\\odot \\right)} \\right)^{0.54},\r\n\\end{eqnarray*}$$where SFR is the ‘instantaneous’ SFR associated with the star-forming gas cells (for consistency with Hayward et al. 2011) and Mdust is the dust mass. When applying the relation, following Hayward et al. (2013b), we incorporate a scatter of 0.13 dex (independent of SFR and dust mass) assuming a Gaussian distribution (Hayward et al. 2011). The submm flux densities predicted using this relation also agree well with the results of performing dust radiative transfer directly on cosmological zoom simulations (Liang et al. 2018; Cochrane et al. 2019) and a semi-analytical model ( Benson, private communication). Moreover, by combining the above with the observed SFR–M⋆ and Mdust(M⋆, z) relations, one can derive an S850–M⋆ relation (Hayward 2012; Hayward et al. 2013a) that agrees reasonably well with that observed for SMGs (Davies et al. 2013). Although given sufficient resolution and unlimited computing time, it would be preferred to perform radiative transfer directly, our approach has the advantage of trivial computational expense, and it may actually be more accurate than direct radiative transfer given the resolution of state-of-the-art large-volume simulations such as Illustris and IllustrisTNG .","Citation Text":["Hayward et al. 2011"],"Citation Start End":[[1135,1154]]} {"Identifier":"2021MNRAS.502.2922H__Hayward_et_al._2011_Instance_3","Paragraph":"As discussed in Section 1, to identify SMGs in the simulation, it is ideal to compute individual simulated galaxies’ submm flux densities via dust radiative transfer. The mass and spatial resolution of Illustris and IllustrisTNG are insufficient to resolve the subkpc structure of the ISM, and owing to both the subgrid equation-of-state treatment of stellar feedback and resolution, such simulations tend to feature overly puffy discs and thus underestimate the attenuation (Trayford et al. 2017). Consequently, we do not perform radiative transfer directly. Instead, we use the following relation based on the results of performing radiative transfer on higher resolution hydrodynamical simulations of idealized isolated discs and mergers (Hayward et al. 2011, 2013a):\n(1)$$\\begin{eqnarray*}\r\n\\frac{S_{850}}{\\left(\\text{mJy}\\right)} = 0.81 \\left(\\frac{\\text{SFR}}{100 \\, \\left(\\text{M}_\\odot \\, \\text{yr}^{-1}\\right)} \\right)^{0.43} \\left(\\frac{M_{\\rm dust}}{10^8 \\, \\left(\\text{M}_\\odot \\right)} \\right)^{0.54},\r\n\\end{eqnarray*}$$where SFR is the ‘instantaneous’ SFR associated with the star-forming gas cells (for consistency with Hayward et al. 2011) and Mdust is the dust mass. When applying the relation, following Hayward et al. (2013b), we incorporate a scatter of 0.13 dex (independent of SFR and dust mass) assuming a Gaussian distribution (Hayward et al. 2011). The submm flux densities predicted using this relation also agree well with the results of performing dust radiative transfer directly on cosmological zoom simulations (Liang et al. 2018; Cochrane et al. 2019) and a semi-analytical model ( Benson, private communication). Moreover, by combining the above with the observed SFR–M⋆ and Mdust(M⋆, z) relations, one can derive an S850–M⋆ relation (Hayward 2012; Hayward et al. 2013a) that agrees reasonably well with that observed for SMGs (Davies et al. 2013). Although given sufficient resolution and unlimited computing time, it would be preferred to perform radiative transfer directly, our approach has the advantage of trivial computational expense, and it may actually be more accurate than direct radiative transfer given the resolution of state-of-the-art large-volume simulations such as Illustris and IllustrisTNG .","Citation Text":["Hayward et al. 2011"],"Citation Start End":[[1352,1371]]} {"Identifier":"2017AandA...599A..19V__Farahani_et_al._2010_Instance_1","Paragraph":"Consider a rotating tornado with a straight magnetic field (Ω0 ≠ 0,J0 = 0). In this case, the dispersion relation (14) reduces to (15)\\begin{eqnarray} \\lefteqn{(\\omega^{2}-C_{\\mathrm {A}}^{2}k^{2})(\\omega^{2}-C_{\\rm T}^{2}k^{2})}\\nonumber\\\\ & &+\\frac{a^2}{4(C_{\\mathrm {A}}^{2}+C_{\\rm s}^{2})}\\left[4\\Omega_{0}^{2}\\omega^{4}-2\\Omega_0^2k^2C_{\\rm s}^2\\omega^{2} -2\\Omega_0^2k^{4}C_{\\rm s}^{2}C_{\\mathrm {A}}^{2})\\right]\\nonumber\\\\ & &-\\frac{a^2}{4(C_{\\mathrm {A}}^{2}+C_{\\rm s}^{2})}\\left[(\\omega^{2}-C_{\\mathrm {A}}^{2}k^{2})^{2}(\\omega^{2}-C_{\\rm s}^{2}k^{2})\\right]=\\left(\\frac{\\rho_{0e}}{2\\rho_0}\\right)\\nonumber\\\\ & & \\times \\frac{(\\omega^2-k^2C_\\mathrm{A}^2)(\\omega^2-k^2C_{\\rm s}^2)(\\omega^2-k^2C_{\\mathrm{Ae}}^2)a}{(C_\\mathrm{A}^2+C_{\\rm s}^2)m_{\\rm e}}\\frac{K_0(m_{\\rm e}a)}{K_1(m_{\\rm e}a)}\\cdot \\label{rotationext} \\end{eqnarray}(ω2−CA2k2)(ω2−CT2k2)+a24(CA2+Cs2)[4Ω02ω4−2Ω02k2Cs2ω2−2Ω02k4Cs2CA2)]−a24(CA2+Cs2)[(ω2−CA2k2)2(ω2−Cs2k2)]=ρ0e2ρ0The second term on the left-hand side of Eq. (15) shows the effect of the internal rotation where the third term indicates the confinement of the tube. The term on the right-hand side of Eq. (15) shows the effect of the perturbations of the external medium. If we write the dispersion relation in terms of the fast and slow speeds we would have (16)\\begin{eqnarray} &&\\left(C_{\\mathrm {A}}^{2}+C_{\\rm s}^{2}+2{\\cal R}C_{\\mathrm {A}}^{2}\\right)\\left(\\omega^{2}-C_{+}^{2}k^{2}\\right)\\left(\\omega^{2}- C_{-}^{2}k^{2}\\right)\\nonumber\\\\ &&\\quad-\\frac{a^2}{4}\\left(\\omega^{2}-C_{\\mathrm {A}}^{2}k^{2}\\right)^{2}\\left(\\omega^{2}-C_{\\rm s}^{2}k^{2}\\right)= \\left(\\frac{\\rho_{0e}}{2\\rho_0}\\right)\\nonumber\\\\&&\\qquad\\times \\frac{\\left(\\omega^2-k^2C_\\mathrm{A}^2\\right)\\left(\\omega^2-k^2C_{\\rm s}^2\\right)\\left(\\omega^2-k^2C_{\\mathrm{Ae}}^2\\right)a}{m_{\\rm e}}\\frac{K_0(m_{\\rm e}a)}{K_1(m_{\\rm e}a)}, \\end{eqnarray}(CA2+Cs2+2ℛCA2)(ω2−C+2k2)(ω2−C−2k2) −a24(ω2−CA2k2)2(ω2−Cs2k2)=ρ0e2ρ0  ×(ω2−k2CA2)(ω2−k2Cs2)(ω2−k2CAe2)ameK0(mea)K1(mea),where (17)\\begin{eqnarray} \\label{PhaseRotation} C_{\\pm}^{2}&=&C_{\\mathrm {A}}^{2}\\frac{(C_{\\mathrm {A}}^{2}+2C_{\\mathrm {s}}^{2})+{\\cal R}C_{\\mathrm {s}}^{2}\\pm\\sqrt{{\\cal P}}}{2(C_{\\mathrm {A}}^{2}+C_{\\mathrm {s}}^{2})+4C_{\\mathrm {A}}^{2}{\\cal R}},\\nonumber\\\\ {\\cal P}&=&C_{\\mathrm {A}}^{4}-2{\\cal R}C_{\\mathrm {s}}^{2}(C_{\\mathrm {A}}^{2}-4C_{\\mathrm {s}}^2)+{\\cal R}^{2}C_{\\mathrm {s}}^{2}(8C_{\\mathrm {A}}^{2}+C_{\\mathrm {s}}^{2}), \\end{eqnarray}C±2=CA2(CA2+2Cs2)+ℛCs2±𝒫2(CA2+Cs2)+4CA2ℛ,𝒫=CA4−2ℛCs2(CA2−4Cs2)+ℛ2Cs2(8CA2+Cs2),and the dimensionless parameter, ℛ, representing the rotation is (18)\\begin{equation} {\\cal R}=\\frac{a^2\\Omega^{2}_{0}}{2\\,C_{\\mathrm {A}}^{2}}\\cdot \\end{equation}ℛ=a2Ω022 CA2·Equation (17) indicates the modification of the Alfvén speed and the tube speed by the equilibrium rotation to the fast (C+) and slow (C−) magnetosonic speeds, respectively (see also Zhugzhda & Nakariakov 1999; Vasheghani Farahani et al. 2010). As such the torsional wave would propagate with the speed C+, and the longitudinal wave would propagate with the speed C−. If we consider the dispersion to be weak (k2A0 ≪ 1), and take \\hbox{$\\omega^{2}\\approx\\,C_{\\pm}^{2}k^{2}$}ω2≈ C±2k2, an explicit expression for the dispersion relation could be obtained (19)\\begin{eqnarray} \\label{PhaseR} \\omega^{2}&\\approx&\\,C_{\\pm}^{2}k^{2}\\pm\\,\\frac{a^2}{4}\\frac{(C_{\\pm}^{2}-C_{\\mathrm {A}}^{2})^{2}(C_{\\pm}^{2}-C_{\\mathrm {s}}^{2})}{C_{\\mathrm {A}}^{2}\\,\\sqrt{{\\cal P}}}k^{4}+ \\left(\\frac{\\rho_{0e}}{2\\rho_0}\\right)\\nonumber\\\\&&\\quad\\times \\frac{(C_{\\pm}^2-C_\\mathrm{A}^2)(C_{\\pm}^2-C_{\\rm s}^2)(C_{\\pm}^2-C_{\\mathrm{Ae}}^2)a}{GC_{\\mathrm {A}}^{2}\\,\\sqrt{{\\cal P}}}\\nonumber\\\\&&\\quad\\times\\frac{K_0(Ga)}{K_1(Ga)}k^4, \\end{eqnarray}ω2≈ C±2k2± a24(C±2−CA2)2(C±2−Cs2)CA2 𝒫k4+ρ0e2ρ0 ×(C±2−CA2)(C±2−Cs2)(C±2−CAe2)aGCA2 𝒫 ×K0(Ga)K1(Ga)k4,where (20)\\begin{eqnarray} G^2=\\frac{\\left(k^2C^2_{\\mathrm{Ae}}-C_{\\pm}^2\\right)\\left(k^2C^2_{\\rm se}-C_{\\pm}^2\\right)} {\\left(C^2_{\\mathrm{Ae}}+C^2_{\\rm se}\\right)\\left(k^2C^2_{\\rm Te}-C_{\\pm}^2\\right)}, \\,\\mbox{ \\ } C_{\\rm Te}^{2}=\\frac{C_{\\mathrm {Ae}}^{2}C_{\\rm se}^{2}}{C_{\\mathrm {A}e}^{2}+C_{\\rm se}^{2}}\\cdot \\label{me} \\end{eqnarray}G2=(k2CAe2−C±2)(k2Cse2−C±2)(CAe2+Cse2)(k2CTe2−C±2), CTe2=CAe2Cse2CAe2+Cse2·The second term on the right-hand side of Eq. (19) is the dispersive correction term, while the third term on the right-hand side represents the effects of the perturbation of the external medium. Equation (19) clearly shows the interplay of the equilibrium rotation and the density contrast of the internal and external media. The modification of the speeds at k = 0 is clearly exhibited by both the rotation and the density contrast. Hence, the modification of the tube and Alfvén speeds to the slow and fast magnetoacoustic speeds is clearly observed, see also Zhugzhda & Nakariakov (1999). In the long wavelength limit where the tube radius is much smaller than the wavelength, the dispersion would be week, therefore the arguments of the modified Bessel function of the second kind K would be small. In such a regime we are able to use the first terms of the expansions of the modified Bessel function of the second kind for small arguments (Abramowitz et al. 1988) which are (21)\\begin{eqnarray} K_{0}(Ga)=-\\mathrm{ln}\\left(\\frac{1}{2}Ga\\right),\\,\\,\\,\\,\\,\\,\\,\\,\\, K_{1}(Ga)=\\frac{1}{Ga}\\cdot \\label{K} \\end{eqnarray}K0(Ga)=−ln12Ga,         K1(Ga)=1Ga·By substituting the terms of Eq. (21) in Eq. (19) we obtain an explicit expression that is easier to read: (22)\\begin{eqnarray} \\omega^{2}\\approx\\,C_{\\pm}^{2}k^{2}\\pm\\,\\frac{a^2}{4}\\frac{(C_{\\pm}^{2}-C_{\\mathrm {A}}^{2})^{2}(C_{\\pm}^{2}-C_{\\mathrm {s}}^{2})}{C_{\\mathrm {A}}^{2}\\,\\sqrt{{\\cal P}}}k^{4}- \\left(\\frac{\\rho_{0e}}{\\rho_0}\\right)\\nonumber\\\\\\times \\frac{a^2}{2}\\frac{(C_{\\pm}^2-C_\\mathrm{A}^2)(C_{\\pm}^2-C_{\\rm s}^2)(C_{\\pm}^2-C_{\\mathrm{Ae}}^2)}{ C_{\\mathrm {A}}^{2}\\,\\sqrt{{\\cal P}}}\\mathrm{ln}\\left(\\frac{1}{2}Ga\\right)k^4. \\label{PhaseR2} \\end{eqnarray}ω2≈ C±2k2± a24(C±2−CA2)2(C±2−Cs2)CA2 𝒫k4−ρ0eρ0×a22(C±2−CA2)(C±2−Cs2)(C±2−CAe2)CA2 𝒫ln12Gak4.Equation (22) represents the dispersion relation for magnetoacoustic waves propagating in a steadily rotating magnetic flux tube (e.g. a solar tornado), which is more convenient for observation purposes and coronal seismology. ","Citation Text":["Vasheghani Farahani et al. 2010"],"Citation Start End":[[2955,2986]]} {"Identifier":"2020ApJ...889..137M__Bhatawdekar_et_al._2019_Instance_1","Paragraph":"Evolution of the SMD (top) and SFRD (bottom) along the cosmic history (see top axis for the corresponding redshift). For these plots, we assumed all three BBG candidates without ALMA detection to be real passive galaxies at z ∼ 6. In the top panel, the SMD of our BBG sample at z ∼ 6 (red circle) is shown in conjunction with those of star-forming (cyan symbols) and passive (magenta symbols) galaxies at lower redshifts from the literature (M13: Muzzin et al. 2013; D14: Duncan et al. 2014; S14: Straatman et al. 2014; G15: Grazian et al. 2015; S16: Song et al. 2016; D17: Davidzon et al. 2017; B19: Bhatawdekar et al. 2019; K19: Kikuchihara et al. 2019). The vertical error bar associated with our BBG data corresponds to a 1σ uncertainty propagated from the Poisson error (Gehrels 1986) for the BBG number and the SED fitting uncertainty for the stellar mass. The horizontal error bar shows the redshift range expected from our BBG color selection. In the bottom panel, the red shaded region corresponds to the SFRD expected from the progenitors of the z ∼ 6 BBGs at a 99.7% confidence level (3σ). The SFRD measurements at \n\n\n\n\n\n are collected from the literature (MD14: Madau & Dickinson 2014; O13: Oesch et al. 2013; O14: Oesch et al. 2014; F15: Finkelstein et al. 2015a; M16: McLeod et al. 2016; B16: Bouwens et al. 2016; I18: Ishigaki et al. 2018; O18: Oesch et al. 2018; B19: Bhatawdekar et al. 2019). All of them at \n\n\n\n\n\n are estimated by integrating the UVLFs down to MUV = −17 mag. The SFRD estimated at z ∼ 17 from an observed global 21 cm absorption trough (M18: Madau 2018; Bowman et al. 2018) is also shown in yellow. The functional fit to the MD14 data, which is proportional to (1 + z)−2.9 at high-z (Madau & Dickinson 2014), is superposed by the solid line. Two other power-law functions supporting an accelerated evolution at z ≳ 8 (\n\n\n\n\n\n Oesch et al. 2014) and a smooth evolution from lower redshift (\n\n\n\n\n\n Finkelstein et al. 2015a) are shown by dotted–dashed and dotted lines, respectively. The SFRD derived assuming a universal relation among the halo mass, SFR, and dark matter accretion rate (Harikane et al. 2018) is also superposed by the gray shade in its 1σ uncertainty. All of the SMD and SFRD measurements from the literature are corrected for the stellar IMF and the cosmological model to match those in this work.","Citation Text":["Bhatawdekar et al. 2019"],"Citation Start End":[[601,624]]} {"Identifier":"2020ApJ...889..137M__Bhatawdekar_et_al._2019_Instance_2","Paragraph":"Evolution of the SMD (top) and SFRD (bottom) along the cosmic history (see top axis for the corresponding redshift). For these plots, we assumed all three BBG candidates without ALMA detection to be real passive galaxies at z ∼ 6. In the top panel, the SMD of our BBG sample at z ∼ 6 (red circle) is shown in conjunction with those of star-forming (cyan symbols) and passive (magenta symbols) galaxies at lower redshifts from the literature (M13: Muzzin et al. 2013; D14: Duncan et al. 2014; S14: Straatman et al. 2014; G15: Grazian et al. 2015; S16: Song et al. 2016; D17: Davidzon et al. 2017; B19: Bhatawdekar et al. 2019; K19: Kikuchihara et al. 2019). The vertical error bar associated with our BBG data corresponds to a 1σ uncertainty propagated from the Poisson error (Gehrels 1986) for the BBG number and the SED fitting uncertainty for the stellar mass. The horizontal error bar shows the redshift range expected from our BBG color selection. In the bottom panel, the red shaded region corresponds to the SFRD expected from the progenitors of the z ∼ 6 BBGs at a 99.7% confidence level (3σ). The SFRD measurements at \n\n\n\n\n\n are collected from the literature (MD14: Madau & Dickinson 2014; O13: Oesch et al. 2013; O14: Oesch et al. 2014; F15: Finkelstein et al. 2015a; M16: McLeod et al. 2016; B16: Bouwens et al. 2016; I18: Ishigaki et al. 2018; O18: Oesch et al. 2018; B19: Bhatawdekar et al. 2019). All of them at \n\n\n\n\n\n are estimated by integrating the UVLFs down to MUV = −17 mag. The SFRD estimated at z ∼ 17 from an observed global 21 cm absorption trough (M18: Madau 2018; Bowman et al. 2018) is also shown in yellow. The functional fit to the MD14 data, which is proportional to (1 + z)−2.9 at high-z (Madau & Dickinson 2014), is superposed by the solid line. Two other power-law functions supporting an accelerated evolution at z ≳ 8 (\n\n\n\n\n\n Oesch et al. 2014) and a smooth evolution from lower redshift (\n\n\n\n\n\n Finkelstein et al. 2015a) are shown by dotted–dashed and dotted lines, respectively. The SFRD derived assuming a universal relation among the halo mass, SFR, and dark matter accretion rate (Harikane et al. 2018) is also superposed by the gray shade in its 1σ uncertainty. All of the SMD and SFRD measurements from the literature are corrected for the stellar IMF and the cosmological model to match those in this work.","Citation Text":["Bhatawdekar et al. 2019"],"Citation Start End":[[1384,1407]]} {"Identifier":"2017AandA...605A..96D__Laskar_&_Robutel_(1995)_Instance_1","Paragraph":"I denote by λi and ϖi the mean longitude and longitude of periastron of planet i (in astrocentric coordinates), respectively. The actions canonically conjugated to the angles λi and −ϖi are the circular angular momentum Λi and the angular momentum deficit (AMD, see Laskar 2000) Di, respectively. These actions are defined as follows \\begin{eqnarray} \\Lambda_i &=& \\beta_i\\sqrt{\\mu_i a_i},\\\\ D_i &=& \\Lambda_i-G_i = \\Lambda_i \\left(1-\\sqrt{1-e_i^2}\\right), \\end{eqnarray}Λi=βiμiai,Di=Λi−Gi=Λi1−1−ei2,where \\hbox{$G_i=\\Lambda_i\\sqrt{1-e_i^2}$}Gi=Λi1−ei2 is the angular momentum of planet i, βi = mim0\/ (m0 + mi), \\hbox{$\\mu_i = \\G (m_0+m_i)$}μi = 𝒢(m0 + mi). At low eccentricities the deficit of angular momentum Di is proportional to \\hbox{$e_i^2$}ei2. The Hamiltonian (Eq. (3)) can be expressed using these action-angle coordinates (6)\\begin{equation} \\label{eq:hamLaD} \\H = - \\sum_{i=1}^n \\frac{\\mu_i^2\\beta_i^3}{2\\Lambda_i^2} + \\sum_{1\\leq i 5.4. Thus, for\n the SYN-SSC process, the plasmon must be adiabatically compressed with at least\n SSSC\/SSYN ∝\n R-5.4. Therefore, the observed\n increase of the X-ray-to-NIR flux ratio by a factor of 10 in 1.2 h implies a decrease\n of the radius by a factor of about 0.6. The average compression velocity is estimated\n as Vcomp =\n ΔR\/ Δt, leading to\n | Vcomp |\n \/c 0.0034\n R\/Rs with\n Rs the Schwarzschild radius\n (Rs = 1.2 ×\n 1012 cm for Sgr A*, which corresponds to 0.08 au). For\n comparison, the expansion velocities computed with this model in the literature range\n between 0.0028 and 0.15c (Yusef-Zadeh et\n al. 2006a, 2009; Eckart et al. 2008), which is of the same order as the compression\n velocity computed here. Thus, the model of an adiabatic compression of a plasmon is\n the likely hypothesis to explain the variation of the ratio between X-ray and NIR\n flux, in the context of the SYN-SSC process. ","Citation Text":["Marscher 1983"],"Citation Start End":[[2349,2362]]} {"Identifier":"2016AandA...589A.116M__Marscher_1983_Instance_1","Paragraph":"During synchrotron self-Compton emission, X-ray photons are produced by the\n scattering of the synchrotron radiation from radio to NIR on their own electron\n population. If we compare the fluxes produced by the synchrotron and SSC emissions,\n the variation of the X-ray\/NIR ratio constrains the size evolution of the flaring\n source. Let us consider a spherical source of radius R with a power law\n energy distribution of relativistic electrons. Following Van der Laan (1966), the radiative transfer for the synchrotron\n radiation can be computed as (2)\\begin{equation} S_\\mathrm{SYN}=\\int_{0}^{R}{\\frac{\\epsilon_\\nu}{\\kappa_\\nu}\\,\\left(1-{\\rm e}^{-\\tau_\\nu(r)}\\right)\\,2\\pi r\\,{\\rm d}r} , \\end{equation}\n\n\nS\nSYN\n\n=\n\n∫\n0\nR\n\n\n\n\n\nϵ\nν\n\n\nκ\nν\n\n\n\n \n\n(\n1\n−\n\ne\n\n−\n\nτ\nν\n\n(\nr\n)\n\n\n)\n\n \n2\nπr\n \nd\nr\n\n,\n\nwith κν ∝\n B(p +\n 2)\/2ν−(p +\n 4)\/2 the absorption coefficient, ϵν ∝\n B(p +\n 1)\/2ν−(p −\n 1)\/2 the emission coefficient, B the magnetic field\n (Lang 1999) and τν(r)\n the optical depth, which can be computed at each distance r from the sphere\n center as: (3)\\begin{equation} \\tau_\\nu(r)=\\int_{0}^{2\\sqrt{R^2-r^2}}{\\kappa_\\nu {\\rm d}l} . \\end{equation}\n\n\nτ\nν\n\n(\nr\n)\n=\n\n∫\n0\n\n2\n\n\n\n\n\nR\n\n2\n\n\n−\n\nr\n\n2\n\n\n\n\n\n\n\n\n\n\nκ\nν\n\nd\nl\n\n.\n\nAssuming that we are in the optically\n thin regime (i.e., τν(r) ≪\n 1), we utilize formula 3 of Marrone\n et al. (2008): SSYN ∝ B(p +\n 1)\/2ν−(p −\n 1)\/2R3. For synchrotron\n radiation, we have \\hbox{$B \\propto R^4\\,\\nu_\\mathrm{m}^{5}\\,S_\\mathrm{m}^{-2}$}\nB\n∝\n\nR\n4\n\n \n\nν\nm\n5\n\n \n\nS\nm\n-2\n\n with Sm the\n maximum flux density of the spectral energy distribution occurring at frequency\n νm (Marscher 1983). Finally, the synchrotron radiation can be expressed using\n p = 2α\n + 1 as (4)\\begin{equation} S_\\mathrm{SYN} \\propto R^{4\\alpha+7}\\,\\nu_\\mathrm{m}^{5(\\alpha+1)}\\,S_\\mathrm{m}^{-2(\\alpha+1)}\\,\\nu^{-\\alpha}\\, . \\end{equation}\n\n\nS\nSYN\n\n∝\n\nR\n\n4\nα\n+\n7\n\n\n \n\nν\nm\n\n5\n(\nα\n+\n1\n)\n\n\n \n\nS\nm\n\n−\n2\n(\nα\n+\n1\n)\n\n\n \n\nν\n\n−\nα\n\n\n \n.\n\nThe SSC radiation of X-ray photons is\n (formula 4 of Marscher 1983):\n (5)\\begin{equation} S_\\mathrm{SSC} \\propto R^{-2(2\\alpha+3)}\\,\\nu_\\mathrm{m}^{-(3\\alpha+5)}\\,S_\\mathrm{m}^{2(\\alpha+2)}\\,\\ln \\left(\\frac{\\nu_2}{\\nu_\\mathrm{m}}\\right)\\,\\nu^{-\\alpha} . \\end{equation}\n\n\nS\nSSC\n\n∝\n\nR\n\n−\n2\n(\n2\nα\n+\n3\n)\n\n\n \n\nν\nm\n\n−\n(\n3\nα\n+\n5\n)\n\n\n \n\nS\nm\n\n2\n(\nα\n+\n2\n)\n\n\n \nln\n\n\n\n\nν\n2\n\n\nν\nm\n\n\n\n\n \n\nν\n\n−\nα\n\n\n.\n\nThe natural logarithm in this equation\n could be approximated by c1\n (ν2\/νm)c2\n with c1 =\n 1.8 and c2 = 0.201 (Eckart et al. 2012b). The synchrotron-to-SSC flux ratio is\n (6)\\begin{equation} \\frac{S_\\mathrm{SSC}}{S_\\mathrm{SYN}} \\propto R^{-(8\\alpha+13)}\\,\\nu_\\mathrm{m}^{-(8\\alpha+10+c_2)}\\,S_\\mathrm{m}^{4\\alpha+6}\\, . \\end{equation}\n\n\n\n\nS\nSSC\n\n\nS\nSYN\n\n\n\n∝\n\nR\n\n−\n(\n8\nα\n+\n13\n)\n\n\n \n\nν\nm\n\n−\n(\n8\nα\n+\n10\n+\n\nc\n2\n\n)\n\n\n \n\nS\nm\n\n4\nα\n+\n6\n\n\n \n.\n\nWe therefore have three parameters that\n may vary during the flare to explain the increased ratio of X-ray and NIR flux (Fig.\n 15). Considering the plasmon model, for which\n a spherical source of relativistic electrons expands and cools adiabatically, we have\n (Van der Laan 1966): νm ∝\n R−(8α + 10)\/(2α +\n 5) and Sm ∝ R−(14α +\n 10)\/(2α + 5). Thus, SSSC\/SSYN ∝\n R−β with\n β ≡\n (8α2 + (30−8\n c2)α + 25−10\n c2)\/(2α + 5). We\n first consider the adiabatic expansion. For our observation, the ratio between the\n X-ray and the NIR flux increases during the 2014 Mar. 10 flare, implying that\n R−β must increase\n as the radius R increases. This condition is satisfied if the\n exponent β is negative and thus if the α value is lower than\n −2.5 or is between\n −2.3 and −1.25, which is inconsistent because\n α must\n be positive. The expansion case is thus likely to be rejected under the hypothesis of\n an optically thin plasmon that expands adiabatically. We can also consider the case\n where the plasmon is compressed during its motion through a bottle-neck configuration\n of the magnetic field. We can still use the equations of Van der Laan (1966), since the conservation of the magnetic flux is\n explicitly taken into account. The compression case is thus preferred, because it\n allows positive values of α for β> 5.4. Thus, for\n the SYN-SSC process, the plasmon must be adiabatically compressed with at least\n SSSC\/SSYN ∝\n R-5.4. Therefore, the observed\n increase of the X-ray-to-NIR flux ratio by a factor of 10 in 1.2 h implies a decrease\n of the radius by a factor of about 0.6. The average compression velocity is estimated\n as Vcomp =\n ΔR\/ Δt, leading to\n | Vcomp |\n \/c 0.0034\n R\/Rs with\n Rs the Schwarzschild radius\n (Rs = 1.2 ×\n 1012 cm for Sgr A*, which corresponds to 0.08 au). For\n comparison, the expansion velocities computed with this model in the literature range\n between 0.0028 and 0.15c (Yusef-Zadeh et\n al. 2006a, 2009; Eckart et al. 2008), which is of the same order as the compression\n velocity computed here. Thus, the model of an adiabatic compression of a plasmon is\n the likely hypothesis to explain the variation of the ratio between X-ray and NIR\n flux, in the context of the SYN-SSC process. ","Citation Text":["Marscher 1983"],"Citation Start End":[[1925,1938]]} {"Identifier":"2019MNRAS.486.3027R__Mészáros_et_al._2000a_Instance_1","Paragraph":"The sky distribution of gamma-ray bursts (GRBs; Piran 2004; Mészáros 2006; Vedrenne & Atteia 2009; Gomboc 2012; Kouveliotou, Wijers & Woosley 2012; Kumar & Zhang 2015; Dai, Daigne & Mészáros 2017; Willingale & Mészáros 2017) has been tested intensively and early works claimed that GRBs were distributed isotropically (Meegan et al. 1992; Briggs et al. 1996; Tegmark et al. 1996). As the amount of observational data increased and various methods were applied, it was claimed that the group of short GRBs (T90 2 s; Balázs et al. 2003), which originate in mergers of compact objects such as neutron stars (Paczynski 1986; Eichler et al. 1989; Berger 2014; Abbott et al. 2017a,b,c), was distributed anisotropically (Balázs, Mészáros & Horváth 1998; Balázs et al. 1999; Magliocchetti, Ghirlanda & Celotti 2003; Vavrek et al. 2008; Tarnopolski 2017). Here, T90 is the duration during which 90  per cent of the detected counts from a GRB are accumulated (Kouveliotou et al. 1993). However, several other works claimed different results (Mészáros et al. 2000a; Mészáros, Bagoly & Vavrek 2000b; Litvin et al. 2001; Bernui, Ferreira & Wuensche 2008; Veres et al. 2010; Ukwatta & Woźniak 2016). The works that analysed GRBs with a duration of 2 ≲ T90 ≲ 10 s also found that these bursts were distributed anisotropically (Mészáros et al. 2000a,b; Litvin et al. 2001; Vavrek et al. 2008; Veres et al. 2010). However, Mészáros & Štoček (2003) and Ukwatta & Woźniak (2016) came to different conclusions. Anisotropical distribution on the sky was also proclaimed for very short GRBs (T90 ≤ 100 ms; Cline et al. 2005; Ukwatta & Woźniak 2016). In contrast, the group of long GRBs (T90 > 2 s), which are associated with the collapses of massive stars (Fruchter et al. 2006; Woosley & Bloom 2006), were found to be distributed isotropically (Balázs et al. 1998, 1999; Mészáros et al. 2000a,b; Magliocchetti et al. 2003; Vavrek et al. 2008; Ukwatta & Woźniak 2016; Tarnopolski 2017), although Mészáros & Štoček (2003) again came to a different conclusion. Mészáros et al. (2009a,b) and Mészáros (2017, 2018) have summarized these efforts.","Citation Text":["Mészáros et al. 2000a"],"Citation Start End":[[1033,1054]]} {"Identifier":"2019MNRAS.486.3027R__Mészáros_et_al._2000a_Instance_2","Paragraph":"The sky distribution of gamma-ray bursts (GRBs; Piran 2004; Mészáros 2006; Vedrenne & Atteia 2009; Gomboc 2012; Kouveliotou, Wijers & Woosley 2012; Kumar & Zhang 2015; Dai, Daigne & Mészáros 2017; Willingale & Mészáros 2017) has been tested intensively and early works claimed that GRBs were distributed isotropically (Meegan et al. 1992; Briggs et al. 1996; Tegmark et al. 1996). As the amount of observational data increased and various methods were applied, it was claimed that the group of short GRBs (T90 2 s; Balázs et al. 2003), which originate in mergers of compact objects such as neutron stars (Paczynski 1986; Eichler et al. 1989; Berger 2014; Abbott et al. 2017a,b,c), was distributed anisotropically (Balázs, Mészáros & Horváth 1998; Balázs et al. 1999; Magliocchetti, Ghirlanda & Celotti 2003; Vavrek et al. 2008; Tarnopolski 2017). Here, T90 is the duration during which 90  per cent of the detected counts from a GRB are accumulated (Kouveliotou et al. 1993). However, several other works claimed different results (Mészáros et al. 2000a; Mészáros, Bagoly & Vavrek 2000b; Litvin et al. 2001; Bernui, Ferreira & Wuensche 2008; Veres et al. 2010; Ukwatta & Woźniak 2016). The works that analysed GRBs with a duration of 2 ≲ T90 ≲ 10 s also found that these bursts were distributed anisotropically (Mészáros et al. 2000a,b; Litvin et al. 2001; Vavrek et al. 2008; Veres et al. 2010). However, Mészáros & Štoček (2003) and Ukwatta & Woźniak (2016) came to different conclusions. Anisotropical distribution on the sky was also proclaimed for very short GRBs (T90 ≤ 100 ms; Cline et al. 2005; Ukwatta & Woźniak 2016). In contrast, the group of long GRBs (T90 > 2 s), which are associated with the collapses of massive stars (Fruchter et al. 2006; Woosley & Bloom 2006), were found to be distributed isotropically (Balázs et al. 1998, 1999; Mészáros et al. 2000a,b; Magliocchetti et al. 2003; Vavrek et al. 2008; Ukwatta & Woźniak 2016; Tarnopolski 2017), although Mészáros & Štoček (2003) again came to a different conclusion. Mészáros et al. (2009a,b) and Mészáros (2017, 2018) have summarized these efforts.","Citation Text":["Mészáros et al. 2000a"],"Citation Start End":[[1313,1334]]} {"Identifier":"2019MNRAS.486.3027R__Mészáros_et_al._2000a_Instance_3","Paragraph":"The sky distribution of gamma-ray bursts (GRBs; Piran 2004; Mészáros 2006; Vedrenne & Atteia 2009; Gomboc 2012; Kouveliotou, Wijers & Woosley 2012; Kumar & Zhang 2015; Dai, Daigne & Mészáros 2017; Willingale & Mészáros 2017) has been tested intensively and early works claimed that GRBs were distributed isotropically (Meegan et al. 1992; Briggs et al. 1996; Tegmark et al. 1996). As the amount of observational data increased and various methods were applied, it was claimed that the group of short GRBs (T90 2 s; Balázs et al. 2003), which originate in mergers of compact objects such as neutron stars (Paczynski 1986; Eichler et al. 1989; Berger 2014; Abbott et al. 2017a,b,c), was distributed anisotropically (Balázs, Mészáros & Horváth 1998; Balázs et al. 1999; Magliocchetti, Ghirlanda & Celotti 2003; Vavrek et al. 2008; Tarnopolski 2017). Here, T90 is the duration during which 90  per cent of the detected counts from a GRB are accumulated (Kouveliotou et al. 1993). However, several other works claimed different results (Mészáros et al. 2000a; Mészáros, Bagoly & Vavrek 2000b; Litvin et al. 2001; Bernui, Ferreira & Wuensche 2008; Veres et al. 2010; Ukwatta & Woźniak 2016). The works that analysed GRBs with a duration of 2 ≲ T90 ≲ 10 s also found that these bursts were distributed anisotropically (Mészáros et al. 2000a,b; Litvin et al. 2001; Vavrek et al. 2008; Veres et al. 2010). However, Mészáros & Štoček (2003) and Ukwatta & Woźniak (2016) came to different conclusions. Anisotropical distribution on the sky was also proclaimed for very short GRBs (T90 ≤ 100 ms; Cline et al. 2005; Ukwatta & Woźniak 2016). In contrast, the group of long GRBs (T90 > 2 s), which are associated with the collapses of massive stars (Fruchter et al. 2006; Woosley & Bloom 2006), were found to be distributed isotropically (Balázs et al. 1998, 1999; Mészáros et al. 2000a,b; Magliocchetti et al. 2003; Vavrek et al. 2008; Ukwatta & Woźniak 2016; Tarnopolski 2017), although Mészáros & Štoček (2003) again came to a different conclusion. Mészáros et al. (2009a,b) and Mészáros (2017, 2018) have summarized these efforts.","Citation Text":["Mészáros et al. 2000a"],"Citation Start End":[[1851,1872]]} {"Identifier":"2019MNRAS.486.3027REichler_et_al._1989_Instance_1","Paragraph":"The sky distribution of gamma-ray bursts (GRBs; Piran 2004; Mészáros 2006; Vedrenne & Atteia 2009; Gomboc 2012; Kouveliotou, Wijers & Woosley 2012; Kumar & Zhang 2015; Dai, Daigne & Mészáros 2017; Willingale & Mészáros 2017) has been tested intensively and early works claimed that GRBs were distributed isotropically (Meegan et al. 1992; Briggs et al. 1996; Tegmark et al. 1996). As the amount of observational data increased and various methods were applied, it was claimed that the group of short GRBs (T90 2 s; Balázs et al. 2003), which originate in mergers of compact objects such as neutron stars (Paczynski 1986; Eichler et al. 1989; Berger 2014; Abbott et al. 2017a,b,c), was distributed anisotropically (Balázs, Mészáros & Horváth 1998; Balázs et al. 1999; Magliocchetti, Ghirlanda & Celotti 2003; Vavrek et al. 2008; Tarnopolski 2017). Here, T90 is the duration during which 90  per cent of the detected counts from a GRB are accumulated (Kouveliotou et al. 1993). However, several other works claimed different results (Mészáros et al. 2000a; Mészáros, Bagoly & Vavrek 2000b; Litvin et al. 2001; Bernui, Ferreira & Wuensche 2008; Veres et al. 2010; Ukwatta & Woźniak 2016). The works that analysed GRBs with a duration of 2 ≲ T90 ≲ 10 s also found that these bursts were distributed anisotropically (Mészáros et al. 2000a,b; Litvin et al. 2001; Vavrek et al. 2008; Veres et al. 2010). However, Mészáros & Štoček (2003) and Ukwatta & Woźniak (2016) came to different conclusions. Anisotropical distribution on the sky was also proclaimed for very short GRBs (T90 ≤ 100 ms; Cline et al. 2005; Ukwatta & Woźniak 2016). In contrast, the group of long GRBs (T90 > 2 s), which are associated with the collapses of massive stars (Fruchter et al. 2006; Woosley & Bloom 2006), were found to be distributed isotropically (Balázs et al. 1998, 1999; Mészáros et al. 2000a,b; Magliocchetti et al. 2003; Vavrek et al. 2008; Ukwatta & Woźniak 2016; Tarnopolski 2017), although Mészáros & Štoček (2003) again came to a different conclusion. Mészáros et al. (2009a,b) and Mészáros (2017, 2018) have summarized these efforts.","Citation Text":["Eichler et al. 1989"],"Citation Start End":[[622,641]]} {"Identifier":"2019AandA...631A.16Ferkinhoff_et_al._2011_Instance_1","Paragraph":"The applicability of mid-IR and far-IR FSL as diagnostic tools of the ISM has received a boost thanks to the publication of samples of nearby galaxies observed with the infrared space observatory (ISO) and Herschel (e.g. Brauher et al. 2008; Farrah et al. 2013; Sargsyan et al. 2014; Kamenetzky et al. 2014; Cormier et al. 2015; Cigan et al. 2016; Herrera-Camus et al. 2016; Fernández-Ontiveros et al. 2016; Zhao et al. 2016; Díaz-Santos et al. 2017; Zhang et al. 2018). At high redshift (z ≳ 1), the far-IR FSL conveniently shift into the (sub)millimetre atmospheric windows. The most popular line is clearly [CII] 158 μm, followed by the [CI] 370, 609 μm lines (e.g. Walter et al. 2011; Bothwell et al. 2017). Both single dish submillimetre telescopes and interferometers have also detected the [NII] 122 μm and 205 μm lines at high redshift (Ferkinhoff et al. 2011, 2015; Combes et al. 2012; Nagao et al. 2012; Decarli et al. 2012, 2014; Béthermin et al. 2016; Pavesi et al. 2016; Lu et al. 2017; Tadaki et al. 2019; Novak et al. 2019). After a slow start, the [OIII] 88 μm line is quickly becoming a popular line to confirm redshifts of galaxies in the epoch of reionization (z ≳ 6), where it shifts into the submillimetre atmospheric windows below 500 GHz (Ferkinhoff et al. 2010; Inoue et al. 2016; Carniani et al. 2017; Marrone et al. 2018; Vishwas et al. 2018; Hashimoto et al. 2018, 2019; Walter et al. 2018; Tamura et al. 2019; Tadaki et al. 2019; Novak et al. 2019). Deep Herschel\/SPIRE spectroscopy has also revealed a number of FSL detections, either in individual objects (Valtchanov et al. 2011; Coppin et al. 2012; George et al. 2013; Uzgil et al. 2016; Rigopoulou et al. 2018; Zhang et al. 2018), or in stacked spectra (Wardlow et al. 2017; Wilson et al. 2017; Zhang et al. 2018). These include the only detections of the [OI] 63 μm line at high redshift reported thus far. This [OI]3P2−3P1 line is arguably the best tracer for the star-forming gas, as it traces the very dense (\n\n\n\nn\ncrit\nH\n\n\n$ n^{\\mathrm{H}}_{\\mathrm{crit}} $\n\n\n = 5×105 cm−3) neutral gas (one caveat being the frequeny presence of self-absorption observed in local ultra-luminous IR galaxies, Rosenberg et al. 2015). Like the [CII] line, the [OI] 63 μm line also shows a “deficit” in the most luminous far-IR sources, though with a higher scatter (Graciá-Carpio et al. 2011; Cormier et al. 2015; Díaz-Santos et al. 2017). Surprisingly, this bright FSL has not been frequently observed with ALMA, probably because it is only observable in the highest frequency bands. At least as surprising is that the fainter, but more accessible [OI]3P1−3P0 transition at λrest = 145 μm (\n\n\n\nn\ncrit\nH\n\n\n$ n^{H}_{\\mathrm{crit}} $\n\n\n = 9.5×104 cm−3) has only recently been detected at high redshifts (Novak et al. 2019 report a tentative detection in a z = 7.5 quasar). Also in nearby galaxies, this [OI] 145 μm line has not been observed very frequently as in most cases, it is fainter than the nearby [CII] 158 μm line. After initial detections with ISO (Malhotra et al. 2001; Brauher et al. 2008), Herschel has now detected [OI] 145 μm in significant samples of nearby galaxies (Spinoglio et al. 2015; Cormier et al. 2015; Fernández-Ontiveros et al. 2016; Herrera-Camus et al. 2018), and recently in a z = 6.5 lensed quasar (Yang et al. 2019).","Citation Text":["Ferkinhoff et al. 2011"],"Citation Start End":[[845,867]]} {"Identifier":"2019AandA...631A.167D__Ferkinhoff_et_al._2010_Instance_1","Paragraph":"The applicability of mid-IR and far-IR FSL as diagnostic tools of the ISM has received a boost thanks to the publication of samples of nearby galaxies observed with the infrared space observatory (ISO) and Herschel (e.g. Brauher et al. 2008; Farrah et al. 2013; Sargsyan et al. 2014; Kamenetzky et al. 2014; Cormier et al. 2015; Cigan et al. 2016; Herrera-Camus et al. 2016; Fernández-Ontiveros et al. 2016; Zhao et al. 2016; Díaz-Santos et al. 2017; Zhang et al. 2018). At high redshift (z ≳ 1), the far-IR FSL conveniently shift into the (sub)millimetre atmospheric windows. The most popular line is clearly [CII] 158 μm, followed by the [CI] 370, 609 μm lines (e.g. Walter et al. 2011; Bothwell et al. 2017). Both single dish submillimetre telescopes and interferometers have also detected the [NII] 122 μm and 205 μm lines at high redshift (Ferkinhoff et al. 2011, 2015; Combes et al. 2012; Nagao et al. 2012; Decarli et al. 2012, 2014; Béthermin et al. 2016; Pavesi et al. 2016; Lu et al. 2017; Tadaki et al. 2019; Novak et al. 2019). After a slow start, the [OIII] 88 μm line is quickly becoming a popular line to confirm redshifts of galaxies in the epoch of reionization (z ≳ 6), where it shifts into the submillimetre atmospheric windows below 500 GHz (Ferkinhoff et al. 2010; Inoue et al. 2016; Carniani et al. 2017; Marrone et al. 2018; Vishwas et al. 2018; Hashimoto et al. 2018, 2019; Walter et al. 2018; Tamura et al. 2019; Tadaki et al. 2019; Novak et al. 2019). Deep Herschel\/SPIRE spectroscopy has also revealed a number of FSL detections, either in individual objects (Valtchanov et al. 2011; Coppin et al. 2012; George et al. 2013; Uzgil et al. 2016; Rigopoulou et al. 2018; Zhang et al. 2018), or in stacked spectra (Wardlow et al. 2017; Wilson et al. 2017; Zhang et al. 2018). These include the only detections of the [OI] 63 μm line at high redshift reported thus far. This [OI]3P2−3P1 line is arguably the best tracer for the star-forming gas, as it traces the very dense (\n\n\n\nn\ncrit\nH\n\n\n$ n^{\\mathrm{H}}_{\\mathrm{crit}} $\n\n\n = 5×105 cm−3) neutral gas (one caveat being the frequeny presence of self-absorption observed in local ultra-luminous IR galaxies, Rosenberg et al. 2015). Like the [CII] line, the [OI] 63 μm line also shows a “deficit” in the most luminous far-IR sources, though with a higher scatter (Graciá-Carpio et al. 2011; Cormier et al. 2015; Díaz-Santos et al. 2017). Surprisingly, this bright FSL has not been frequently observed with ALMA, probably because it is only observable in the highest frequency bands. At least as surprising is that the fainter, but more accessible [OI]3P1−3P0 transition at λrest = 145 μm (\n\n\n\nn\ncrit\nH\n\n\n$ n^{H}_{\\mathrm{crit}} $\n\n\n = 9.5×104 cm−3) has only recently been detected at high redshifts (Novak et al. 2019 report a tentative detection in a z = 7.5 quasar). Also in nearby galaxies, this [OI] 145 μm line has not been observed very frequently as in most cases, it is fainter than the nearby [CII] 158 μm line. After initial detections with ISO (Malhotra et al. 2001; Brauher et al. 2008), Herschel has now detected [OI] 145 μm in significant samples of nearby galaxies (Spinoglio et al. 2015; Cormier et al. 2015; Fernández-Ontiveros et al. 2016; Herrera-Camus et al. 2018), and recently in a z = 6.5 lensed quasar (Yang et al. 2019).","Citation Text":["Ferkinhoff et al. 2010"],"Citation Start End":[[1262,1284]]} {"Identifier":"2018ApJ...854..109Z__Kloppenborg_et_al._2010_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Kloppenborg et al. 2010"],"Citation Start End":[[715,738]]} {"Identifier":"2018ApJ...854..109ZKuiper_et_al._1937_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Kuiper et al. 1937"],"Citation Start End":[[547,565]]} {"Identifier":"2018ApJ...854..109ZLissauer_et_al._1996___Strassmeier_et_al._2014_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Lissauer et al. 1996","Strassmeier et al. 2014"],"Citation Start End":[[1122,1142],[1432,1455]]} {"Identifier":"2018ApJ...854..109ZHoard_et_al._2010_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Hoard et al. 2010"],"Citation Start End":[[1224,1241]]} {"Identifier":"2018ApJ...854..109ZBudaj_2011_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Budaj 2011"],"Citation Start End":[[1560,1570]]} {"Identifier":"2018ApJ...854..109ZZola_et_al._1994_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Zola et al. 1994"],"Citation Start End":[[1722,1738]]} {"Identifier":"2018ApJ...854..109ZRodriguez_et_al._2016_Instance_1","Paragraph":"It may be possible for the accretion disks to persist in systems that have ended active mass transfer. Occultations induced by persistent disks have been detected in a handful of long-period binaries. Photometric occultations by disks are often distinct from other events, as they exhibit long-duration, deep eclipse-like signals that can be identified in photometric surveys. Aurigae is the classical example of such a system, with a post-AGB F0 supergiant with a B-star companion embedded in a dusty disk with an orbital period of 27 yr (e.g., Kuiper et al. 1937; Huang 1965; Kopal 1971). The occultation is observed in photometry (e.g., Gyldenkerne 1970; Kemp et al. 1986; Carroll et al. 1991), interferometry (Kloppenborg et al. 2010, 2015), and spectroscopy (e.g., Lambert & Sawyer 1986; Chadima et al. 2011; Leadbeater et al. 2012; Griffin & Stencel 2013; Muthumariappan et al. 2014; Strassmeier et al. 2014), and the system’s orbit and masses are constrained by the radial velocities (Stefanik et al. 2010). The 2 yr long eclipse is inferred to be from a ∼4 au diameter disk consisting of both dust and gas (e.g., Lissauer et al. 1996). The dusty component is required to explain the strong IR excess in the system (Hoard et al. 2010), while the gaseous component in the vertically extended disk shell induces a series of spectroscopic features that map out the Keplerian disk during occultation (e.g., Chadima et al. 2011; Strassmeier et al. 2014). A central brightening is seen during eclipse, leading to a flared disk geometry interpretation (e.g., Budaj 2011). Similar long-period, long-duration disk occultations in other potential mass-transfer systems have also been identified: the 96-day-period V383 Sco (Zola et al. 1994), the 5.6 yr period EE Cep (Mikolajewski & Graczyk 1999), the 468-day periodiocally recurring eclipses of OGLE-LMC-ECL-11893 (Dong et al. 2014; Scott et al. 2014), and the 1277-day periodic eclipses of OGLE-BLG182.1.162852 (Rattenbury et al. 2015). The recent advent of wide-field photometric surveys is now also enabling numerous new discoveries, including the 69 yr eclipsing disk system TYC 2505-672-1 (Rodriguez et al. 2016).","Citation Text":["Rodriguez et al. 2016"],"Citation Start End":[[2145,2166]]} {"Identifier":"2022AandA...666A..6Morello_et_al._2017a_Instance_1","Paragraph":"High-precision photometric measurements have shown that the present treatment of limb darkening is not sufficiently accurate and leads to systematic errors in the derived parameters of the exoplanets (e.g., Espinoza & Jordán 2016; Morello et al. 2017a; Maxted 2018). Typically, limb darkening is represented by rather simple laws, such as a linear law (Schwarzschild 1906), a quadratic law (Kopal 1950), a square-root law (Diaz-Cordoves & Gimenez 1992), a power-2 law (Hestroffer 1997), or a four-coefficients law (Claret 2000), so that when modeling the transit light curves, limb darkening is parameterized by some set of coefficients. Ideally, these coefficients should be constrained by the stellar modeling. Consequently, many libraries of limb-darkening coefficients covering a wide range of effective temperatures (Teff), surface gravity (log g), and metal-licities (M\/H) have been produced (e.g., Claret 2000; Sing 2010; Claret & Bloemen 2011; Magic et al. 2015) using various radiative transfer codes, such as ATLAS (Kurucz 1993), NextGen (Hauschildt et al. 1999), PHOENIX (Husser et al. 2013), MARCS (Gustafsson et al. 2008), and STAGGER (Magic et al. 2013). However, the limb-darkening parameters diverge between different libraries and often lead to an inadequate quality of fits to the observed transit profiles (Csizmadia et al. 2013). First, this can be due to errors in limb-darkening coefficients introduced by interpolation from the grid of stellar parameters used in these libraries to the actual stellar fundamental parameters. Second, available stellar calculations may not treat mechanisms that affect limb darkening with sufficient accuracy, for instance, convection (Pereira et al. 2013; Chiavassa et al. 2017) or magnetic activity (Csizmadia et al. 2013). Therefore, limb-darkening coefficients are often left as free parameters in a least-squares fit to observed light curves (e.g., Southworth 2008; Claret 2009; Cabrera et al. 2010; Gillon et al. 2010; Csizmadia et al. 2013; Maxted 2018). While this method usually leads to a good quality fit to observed transit profiles, it introduces additional free parameters, resulting in possible biases and degeneracies in the returned planetary radii (Espinoza & Jordán 2015; Morello et al. 2017b). The way to reduce these biases and reliably determine planetary radii is to improve theoretical computations of stellar limb darkening.","Citation Text":["Morello et al. 2017a"],"Citation Start End":[[231,251]]} {"Identifier":"2022AandA...666A..6Csizmadia_et_al._2013_Instance_1","Paragraph":"High-precision photometric measurements have shown that the present treatment of limb darkening is not sufficiently accurate and leads to systematic errors in the derived parameters of the exoplanets (e.g., Espinoza & Jordán 2016; Morello et al. 2017a; Maxted 2018). Typically, limb darkening is represented by rather simple laws, such as a linear law (Schwarzschild 1906), a quadratic law (Kopal 1950), a square-root law (Diaz-Cordoves & Gimenez 1992), a power-2 law (Hestroffer 1997), or a four-coefficients law (Claret 2000), so that when modeling the transit light curves, limb darkening is parameterized by some set of coefficients. Ideally, these coefficients should be constrained by the stellar modeling. Consequently, many libraries of limb-darkening coefficients covering a wide range of effective temperatures (Teff), surface gravity (log g), and metal-licities (M\/H) have been produced (e.g., Claret 2000; Sing 2010; Claret & Bloemen 2011; Magic et al. 2015) using various radiative transfer codes, such as ATLAS (Kurucz 1993), NextGen (Hauschildt et al. 1999), PHOENIX (Husser et al. 2013), MARCS (Gustafsson et al. 2008), and STAGGER (Magic et al. 2013). However, the limb-darkening parameters diverge between different libraries and often lead to an inadequate quality of fits to the observed transit profiles (Csizmadia et al. 2013). First, this can be due to errors in limb-darkening coefficients introduced by interpolation from the grid of stellar parameters used in these libraries to the actual stellar fundamental parameters. Second, available stellar calculations may not treat mechanisms that affect limb darkening with sufficient accuracy, for instance, convection (Pereira et al. 2013; Chiavassa et al. 2017) or magnetic activity (Csizmadia et al. 2013). Therefore, limb-darkening coefficients are often left as free parameters in a least-squares fit to observed light curves (e.g., Southworth 2008; Claret 2009; Cabrera et al. 2010; Gillon et al. 2010; Csizmadia et al. 2013; Maxted 2018). While this method usually leads to a good quality fit to observed transit profiles, it introduces additional free parameters, resulting in possible biases and degeneracies in the returned planetary radii (Espinoza & Jordán 2015; Morello et al. 2017b). The way to reduce these biases and reliably determine planetary radii is to improve theoretical computations of stellar limb darkening.","Citation Text":["Csizmadia et al. 2013"],"Citation Start End":[[1326,1347]]} {"Identifier":"2022AandA...666A..6Csizmadia_et_al._2013_Instance_2","Paragraph":"High-precision photometric measurements have shown that the present treatment of limb darkening is not sufficiently accurate and leads to systematic errors in the derived parameters of the exoplanets (e.g., Espinoza & Jordán 2016; Morello et al. 2017a; Maxted 2018). Typically, limb darkening is represented by rather simple laws, such as a linear law (Schwarzschild 1906), a quadratic law (Kopal 1950), a square-root law (Diaz-Cordoves & Gimenez 1992), a power-2 law (Hestroffer 1997), or a four-coefficients law (Claret 2000), so that when modeling the transit light curves, limb darkening is parameterized by some set of coefficients. Ideally, these coefficients should be constrained by the stellar modeling. Consequently, many libraries of limb-darkening coefficients covering a wide range of effective temperatures (Teff), surface gravity (log g), and metal-licities (M\/H) have been produced (e.g., Claret 2000; Sing 2010; Claret & Bloemen 2011; Magic et al. 2015) using various radiative transfer codes, such as ATLAS (Kurucz 1993), NextGen (Hauschildt et al. 1999), PHOENIX (Husser et al. 2013), MARCS (Gustafsson et al. 2008), and STAGGER (Magic et al. 2013). However, the limb-darkening parameters diverge between different libraries and often lead to an inadequate quality of fits to the observed transit profiles (Csizmadia et al. 2013). First, this can be due to errors in limb-darkening coefficients introduced by interpolation from the grid of stellar parameters used in these libraries to the actual stellar fundamental parameters. Second, available stellar calculations may not treat mechanisms that affect limb darkening with sufficient accuracy, for instance, convection (Pereira et al. 2013; Chiavassa et al. 2017) or magnetic activity (Csizmadia et al. 2013). Therefore, limb-darkening coefficients are often left as free parameters in a least-squares fit to observed light curves (e.g., Southworth 2008; Claret 2009; Cabrera et al. 2010; Gillon et al. 2010; Csizmadia et al. 2013; Maxted 2018). While this method usually leads to a good quality fit to observed transit profiles, it introduces additional free parameters, resulting in possible biases and degeneracies in the returned planetary radii (Espinoza & Jordán 2015; Morello et al. 2017b). The way to reduce these biases and reliably determine planetary radii is to improve theoretical computations of stellar limb darkening.","Citation Text":["Csizmadia et al. 2013"],"Citation Start End":[[1757,1778]]} {"Identifier":"2022AandA...666A..6Csizmadia_et_al._2013_Instance_3","Paragraph":"High-precision photometric measurements have shown that the present treatment of limb darkening is not sufficiently accurate and leads to systematic errors in the derived parameters of the exoplanets (e.g., Espinoza & Jordán 2016; Morello et al. 2017a; Maxted 2018). Typically, limb darkening is represented by rather simple laws, such as a linear law (Schwarzschild 1906), a quadratic law (Kopal 1950), a square-root law (Diaz-Cordoves & Gimenez 1992), a power-2 law (Hestroffer 1997), or a four-coefficients law (Claret 2000), so that when modeling the transit light curves, limb darkening is parameterized by some set of coefficients. Ideally, these coefficients should be constrained by the stellar modeling. Consequently, many libraries of limb-darkening coefficients covering a wide range of effective temperatures (Teff), surface gravity (log g), and metal-licities (M\/H) have been produced (e.g., Claret 2000; Sing 2010; Claret & Bloemen 2011; Magic et al. 2015) using various radiative transfer codes, such as ATLAS (Kurucz 1993), NextGen (Hauschildt et al. 1999), PHOENIX (Husser et al. 2013), MARCS (Gustafsson et al. 2008), and STAGGER (Magic et al. 2013). However, the limb-darkening parameters diverge between different libraries and often lead to an inadequate quality of fits to the observed transit profiles (Csizmadia et al. 2013). First, this can be due to errors in limb-darkening coefficients introduced by interpolation from the grid of stellar parameters used in these libraries to the actual stellar fundamental parameters. Second, available stellar calculations may not treat mechanisms that affect limb darkening with sufficient accuracy, for instance, convection (Pereira et al. 2013; Chiavassa et al. 2017) or magnetic activity (Csizmadia et al. 2013). Therefore, limb-darkening coefficients are often left as free parameters in a least-squares fit to observed light curves (e.g., Southworth 2008; Claret 2009; Cabrera et al. 2010; Gillon et al. 2010; Csizmadia et al. 2013; Maxted 2018). While this method usually leads to a good quality fit to observed transit profiles, it introduces additional free parameters, resulting in possible biases and degeneracies in the returned planetary radii (Espinoza & Jordán 2015; Morello et al. 2017b). The way to reduce these biases and reliably determine planetary radii is to improve theoretical computations of stellar limb darkening.","Citation Text":["Csizmadia et al. 2013"],"Citation Start End":[[1980,2001]]} {"Identifier":"2022AandA...666A..6Morello_et_al._2017b_Instance_1","Paragraph":"High-precision photometric measurements have shown that the present treatment of limb darkening is not sufficiently accurate and leads to systematic errors in the derived parameters of the exoplanets (e.g., Espinoza & Jordán 2016; Morello et al. 2017a; Maxted 2018). Typically, limb darkening is represented by rather simple laws, such as a linear law (Schwarzschild 1906), a quadratic law (Kopal 1950), a square-root law (Diaz-Cordoves & Gimenez 1992), a power-2 law (Hestroffer 1997), or a four-coefficients law (Claret 2000), so that when modeling the transit light curves, limb darkening is parameterized by some set of coefficients. Ideally, these coefficients should be constrained by the stellar modeling. Consequently, many libraries of limb-darkening coefficients covering a wide range of effective temperatures (Teff), surface gravity (log g), and metal-licities (M\/H) have been produced (e.g., Claret 2000; Sing 2010; Claret & Bloemen 2011; Magic et al. 2015) using various radiative transfer codes, such as ATLAS (Kurucz 1993), NextGen (Hauschildt et al. 1999), PHOENIX (Husser et al. 2013), MARCS (Gustafsson et al. 2008), and STAGGER (Magic et al. 2013). However, the limb-darkening parameters diverge between different libraries and often lead to an inadequate quality of fits to the observed transit profiles (Csizmadia et al. 2013). First, this can be due to errors in limb-darkening coefficients introduced by interpolation from the grid of stellar parameters used in these libraries to the actual stellar fundamental parameters. Second, available stellar calculations may not treat mechanisms that affect limb darkening with sufficient accuracy, for instance, convection (Pereira et al. 2013; Chiavassa et al. 2017) or magnetic activity (Csizmadia et al. 2013). Therefore, limb-darkening coefficients are often left as free parameters in a least-squares fit to observed light curves (e.g., Southworth 2008; Claret 2009; Cabrera et al. 2010; Gillon et al. 2010; Csizmadia et al. 2013; Maxted 2018). While this method usually leads to a good quality fit to observed transit profiles, it introduces additional free parameters, resulting in possible biases and degeneracies in the returned planetary radii (Espinoza & Jordán 2015; Morello et al. 2017b). The way to reduce these biases and reliably determine planetary radii is to improve theoretical computations of stellar limb darkening.","Citation Text":["Morello et al. 2017b"],"Citation Start End":[[2246,2266]]} {"Identifier":"2019MNRAS.488..954Q__Feldman_et_al._1982_Instance_1","Paragraph":"Not only are electron populations with two different temperatures and densities frequently observed in experimental plasmas (Morales & Lee 1974; Jones et al. 1975), they are also an essential feature of space plasmas (Delory, Ergun & McFadden 1998; Ergun et al. 1998; Pottelette, Berthomier & Malingre 1998). Observations of electron velocity distribution functions (VDFs) in the solar wind and magnetosphere show a clear picture of a non-Maxwellian distribution function, that is, of a dense thermal population ‘core’ superimposed on a hot superthermal population ‘halo’ (Lin 1998; Makimovic et al. 2001; Pierrard, Maksimovic & Lemaire 2001; Pagel et al. 2005; Marsch 2006; Gaelzer et al. 2008). Two-component electron populations are a common feature of interplanetary shocks in the solar wind with relative drifts parallel to the magnetic field (Feldman et al. 1975, 1983b). They are also found around the Earth's bow shock, with a comparatively dense hot component and a tenuous cold beam (Feldman et al. 1982, 1983a). Reiff & Reasoner (1975) presented a comprehensive picture of electron VDFs from in the magnetosheath at lunar distances using Apollo 14. They found two distinct populations of electron VDFs, with the hot population density higher near the bow shock, and the colder one mid-way of the magnetosheath. They found that the two components are distinct but are not completely independent, and that the high- and low-energy components grow at the expense of each other. They argued that the high-energy portion of electron VDFs originates and is accelerated at the bow shock owing to the potential difference across this shock. Marsch (2006) also showed the interdependence of the core and halo components of electron VDFs in the solar wind. Such types of electron VDFs cannot be modelled by a single electron Maxwellian population or by core and halo both modelled by a bi-Maxwellian distribution. However, solar wind electron velocity distributions comprising a bulk core and a tenuous halo population are well fitted by employing a model distribution containing a bulk Maxwellian superimposed on a kappa distribution (Nieves-Chinchilla & Vinas 2008). Schippers et al. (2008) fitted the two-population electron VDFs observed in Saturn's magnetosphere with a combination of the bi-kappa distribution function that was used by Balaku et al. (2011) to study the damping characteristics of electron acoustic waves in Saturn's magnetosphere. Saeed et al. (2017, 2017a) studied the characteristics of electron heat flux and electromagnetic electron cyclotron instabilities by considering the relative drift between the core and halo electron components in typical solar wind conditions.","Citation Text":["Feldman et al. 1982"],"Citation Start End":[[994,1013]]} {"Identifier":"2019MNRAS.488..954QSchippers_et_al._(2008)_Instance_1","Paragraph":"Not only are electron populations with two different temperatures and densities frequently observed in experimental plasmas (Morales & Lee 1974; Jones et al. 1975), they are also an essential feature of space plasmas (Delory, Ergun & McFadden 1998; Ergun et al. 1998; Pottelette, Berthomier & Malingre 1998). Observations of electron velocity distribution functions (VDFs) in the solar wind and magnetosphere show a clear picture of a non-Maxwellian distribution function, that is, of a dense thermal population ‘core’ superimposed on a hot superthermal population ‘halo’ (Lin 1998; Makimovic et al. 2001; Pierrard, Maksimovic & Lemaire 2001; Pagel et al. 2005; Marsch 2006; Gaelzer et al. 2008). Two-component electron populations are a common feature of interplanetary shocks in the solar wind with relative drifts parallel to the magnetic field (Feldman et al. 1975, 1983b). They are also found around the Earth's bow shock, with a comparatively dense hot component and a tenuous cold beam (Feldman et al. 1982, 1983a). Reiff & Reasoner (1975) presented a comprehensive picture of electron VDFs from in the magnetosheath at lunar distances using Apollo 14. They found two distinct populations of electron VDFs, with the hot population density higher near the bow shock, and the colder one mid-way of the magnetosheath. They found that the two components are distinct but are not completely independent, and that the high- and low-energy components grow at the expense of each other. They argued that the high-energy portion of electron VDFs originates and is accelerated at the bow shock owing to the potential difference across this shock. Marsch (2006) also showed the interdependence of the core and halo components of electron VDFs in the solar wind. Such types of electron VDFs cannot be modelled by a single electron Maxwellian population or by core and halo both modelled by a bi-Maxwellian distribution. However, solar wind electron velocity distributions comprising a bulk core and a tenuous halo population are well fitted by employing a model distribution containing a bulk Maxwellian superimposed on a kappa distribution (Nieves-Chinchilla & Vinas 2008). Schippers et al. (2008) fitted the two-population electron VDFs observed in Saturn's magnetosphere with a combination of the bi-kappa distribution function that was used by Balaku et al. (2011) to study the damping characteristics of electron acoustic waves in Saturn's magnetosphere. Saeed et al. (2017, 2017a) studied the characteristics of electron heat flux and electromagnetic electron cyclotron instabilities by considering the relative drift between the core and halo electron components in typical solar wind conditions.","Citation Text":["Schippers et al. (2008)"],"Citation Start End":[[2170,2193]]} {"Identifier":"2020MNRAS.494.2191N__Ribeiro_et_al._2020_Instance_1","Paragraph":"To interpret precisely the finding that high-inclination Centaurs had nearly polar orbits at the end of planet formation, it is useful to recall the current understanding of early Solar system structure (Pfalzner et al. 2015). The Solar system started forming 4.6 Gyr in the past. Sometime after a few Myr, giant planets formed and radially migrated while interacting with the planetesimal disc. The migration relaxation time is thought to have been about 1 to a few 10 Myr whereas the full migration stage is thought to have lasted about a 100–500 Myr at the end of which the planets reached their final orbits. The planets’ orbital evolution in this stage is largely uncertain owing to the multitude of complex processes that operate in the first 100 Myr of planet formation (Ribeiro et al. 2020). What is certain, however, is first, that the planetesimal disc before the migration stage as well as at the end of this stage had a small inclination dispersion in order to explain the very low inclination TNOs currently observed in the Kuiper belt (known as the cold population) (Pfalzner et al. 2015). Secondly, the early planetesimal disc could not have extended beyond 30–40 au (Gomes et al. 2004) to ensure that Neptune does not end up with a much larger final semimajor axis than the current one. Thus the early scattered disc and Oort cloud were devoid of Solar system material. Our orbit determination method was run for 4.5 Gyr in the past. The fact that the planets migrated towards the end of that period is not included in our calculation because the planets’ evolution in the migration stage is largely uncertain but more importantly, because it does not affect the Centaur orbits end states in any significant way. The reason lies in the fact that the bulk of stable Centaur clones that end up on nearly polar orbits do so in the first 1 Gyr of the simulation. Therefore near 4 Gyr in the past, the polar stable clones are already located far away in the scattered disc and the inner Oort cloud. Changes in the planets’ semimajor axes over a few 10 Myr do not affect such distant polar orbits significantly, as in reality, the planets’ effect had long started to decay in the last billion years before migration even occurred.","Citation Text":["Ribeiro et al. 2020"],"Citation Start End":[[778,797]]} {"Identifier":"2020MNRAS.494.2191NGomes_et_al._2004_Instance_1","Paragraph":"To interpret precisely the finding that high-inclination Centaurs had nearly polar orbits at the end of planet formation, it is useful to recall the current understanding of early Solar system structure (Pfalzner et al. 2015). The Solar system started forming 4.6 Gyr in the past. Sometime after a few Myr, giant planets formed and radially migrated while interacting with the planetesimal disc. The migration relaxation time is thought to have been about 1 to a few 10 Myr whereas the full migration stage is thought to have lasted about a 100–500 Myr at the end of which the planets reached their final orbits. The planets’ orbital evolution in this stage is largely uncertain owing to the multitude of complex processes that operate in the first 100 Myr of planet formation (Ribeiro et al. 2020). What is certain, however, is first, that the planetesimal disc before the migration stage as well as at the end of this stage had a small inclination dispersion in order to explain the very low inclination TNOs currently observed in the Kuiper belt (known as the cold population) (Pfalzner et al. 2015). Secondly, the early planetesimal disc could not have extended beyond 30–40 au (Gomes et al. 2004) to ensure that Neptune does not end up with a much larger final semimajor axis than the current one. Thus the early scattered disc and Oort cloud were devoid of Solar system material. Our orbit determination method was run for 4.5 Gyr in the past. The fact that the planets migrated towards the end of that period is not included in our calculation because the planets’ evolution in the migration stage is largely uncertain but more importantly, because it does not affect the Centaur orbits end states in any significant way. The reason lies in the fact that the bulk of stable Centaur clones that end up on nearly polar orbits do so in the first 1 Gyr of the simulation. Therefore near 4 Gyr in the past, the polar stable clones are already located far away in the scattered disc and the inner Oort cloud. Changes in the planets’ semimajor axes over a few 10 Myr do not affect such distant polar orbits significantly, as in reality, the planets’ effect had long started to decay in the last billion years before migration even occurred.","Citation Text":["Gomes et al. 2004"],"Citation Start End":[[1183,1200]]} {"Identifier":"2015ApJ...806...13M__Brueckner_et_al._1995_Instance_1","Paragraph":"From the list of major SEP events with a metric type II burst, we selected all those events for which adequate GOES data of the associated soft X-ray flare was available. We used GOES 1–8 Å X-ray profiles and the daily NOAA Solar Event Reports (Edited Events) (http:\/\/www.swpc.noaa.gov\/ftpmenu\/warehouse.html) to determine the magnitude and the onset and peak times of the associated GOES X-ray flare. Flare locations are taken from NOAA reports or determined from images of the EIT (Delaboudinière et al. 1995) on board the Solar and Heliospheric Observatory (SOHO). The associated CMEs were identified using the Large Angle and Spectrometric Coronagraph (LASCO; Brueckner et al. 1995) CME catalog (http:\/\/cdaw.gsfc.nasa.gov\/CME_list\/index.html; Yashiro et al. 2004; Gopalswamy et al. 2009b). Our final data set consists of 59 SEP events listed in Table 1. The columns in Table 1 are: the type II date (1) and time (2), the first observation date (3) and time (4) of the associated CME, the CME space speed (5) and width (6), the location of the associated flare (7), the flare-onset date (8) and time (9), the flare peak date (10) and time (11), the magnitude of the flare (12), the calculated constant acceleration of the CME (13), and the height of the CME (14) at the type II onset calculated using the flare-onset method. The last column (15) of Table 1 gives the measured height of the CME at the type II onset obtained by 3D-fitting a spherical shock model to CME images. The onset times of the metric type II bursts listed in Table 1 are the earliest reported times compiled from the NOAA Solar Event Reports except for the onset times of the 2000 June 6 and November 8 events that are from Gopalswamy (2003). Often different observatories report different onset times for the same metric type II burst; therefore, by selecting the earliest onset times we guarantee that our estimation is the lowest CME height consistent with the radio observations. Some additional details of the entries in Table 1 are given in Sections 3 and 5 discussing data analysis methods.","Citation Text":["Brueckner et al. 1995"],"Citation Start End":[[665,686]]} {"Identifier":"2015ApJ...806...13MGopalswamy_(2003)_Instance_1","Paragraph":"From the list of major SEP events with a metric type II burst, we selected all those events for which adequate GOES data of the associated soft X-ray flare was available. We used GOES 1–8 Å X-ray profiles and the daily NOAA Solar Event Reports (Edited Events) (http:\/\/www.swpc.noaa.gov\/ftpmenu\/warehouse.html) to determine the magnitude and the onset and peak times of the associated GOES X-ray flare. Flare locations are taken from NOAA reports or determined from images of the EIT (Delaboudinière et al. 1995) on board the Solar and Heliospheric Observatory (SOHO). The associated CMEs were identified using the Large Angle and Spectrometric Coronagraph (LASCO; Brueckner et al. 1995) CME catalog (http:\/\/cdaw.gsfc.nasa.gov\/CME_list\/index.html; Yashiro et al. 2004; Gopalswamy et al. 2009b). Our final data set consists of 59 SEP events listed in Table 1. The columns in Table 1 are: the type II date (1) and time (2), the first observation date (3) and time (4) of the associated CME, the CME space speed (5) and width (6), the location of the associated flare (7), the flare-onset date (8) and time (9), the flare peak date (10) and time (11), the magnitude of the flare (12), the calculated constant acceleration of the CME (13), and the height of the CME (14) at the type II onset calculated using the flare-onset method. The last column (15) of Table 1 gives the measured height of the CME at the type II onset obtained by 3D-fitting a spherical shock model to CME images. The onset times of the metric type II bursts listed in Table 1 are the earliest reported times compiled from the NOAA Solar Event Reports except for the onset times of the 2000 June 6 and November 8 events that are from Gopalswamy (2003). Often different observatories report different onset times for the same metric type II burst; therefore, by selecting the earliest onset times we guarantee that our estimation is the lowest CME height consistent with the radio observations. Some additional details of the entries in Table 1 are given in Sections 3 and 5 discussing data analysis methods.","Citation Text":["Gopalswamy (2003)"],"Citation Start End":[[1701,1718]]} {"Identifier":"2022AandA...658A.18Oey_&_Clarke_(1998)_Instance_1","Paragraph":"The trends between the LF slope α and the aforementioned parameters, with the addition of the morphological T type, are shown in Fig. 4 together with their Spearman correlation coefficient (ρ) and their p value, indicating the probability that the two sets of data are uncorrelated. We summarize the properties for which we look for a correlation in Table 4. We define a correlation to be negligible when |ρ|=[0 − 0.2], weak when |ρ|=[0.2 − 0.4], moderate when |ρ|=[0.4 − 0.6], strong when |ρ|=[0.6 − 0.8], and very strong when |ρ|=[0.8 − 1]; using the p value to evaluate the probability that, despite showing a correlation, two variables may be uncorrelated. It should be noted that only a handful of studies so far have looked at the correlation between α and global galaxy properties: Kennicutt et al. (1989), Elmegreen & Salzer (1999), Youngblood & Hunter (1999), van Zee (2000), and Thilker et al. (2002) investigated nebular LFs as in this paper, while Liu et al. (2013) identified H II regions via Paα, and Cook et al. (2016) studied the GALEX far-ultraviolet (FUV) LFs of H II regions. While the sample of Cook et al. (2016) includes a few hundred galaxies, the other studies are based on samples ranging from 10 to 35 galaxies, similar to our study. In this section and in Sect. 6.1, we compare our results to those studies that, as in our case, applied a uniform analysis methodology on galaxy samples. It should be noted that using different tracers means probing different source ages and, as reported by Oey & Clarke (1998), older H II regions tend to have steeper LF slopes, mainly due to the short main-sequence lifetimes of the more massive stars constituting the brighter H II regions. This is the reason why, for example, FUV observations, probing H II regions with ages less than 100 Myr, are expected to deliver a steeper LF compared to Hα observations, typically probing H II regions younger than 10 Myr, and our comparison remains qualitative.","Citation Text":["Oey & Clarke (1998)"],"Citation Start End":[[1518,1537]]} {"Identifier":"2016MNRAS.455..552BWeinberg_et_al._2013_Instance_1","Paragraph":"The plethora of cosmological observations has turned cosmology into a quantitative science. From combining several probes that observe the Universe at different epochs and have different systematics and statistics, emerged the ‘concordance model’ of cosmology, a six parameter model, most of them measured to the accuracy of a per cent. Among these probes, Type Ia supernovae (SNe) are a powerful cosmological tool to directly measure the expansion history of the Universe (see e.g. a recent review of Weinberg et al. 2013). The type Ia SNe are known to be standard candles and one can measure the luminosity distances to them accurately. Several SNe surveys have set strong constraints on cosmological models from the distance–redshift relation (e.g. Riess et al. 1998; Perlmutter et al. 1999; Riess et al. 2007; Sullivan et al. 2011; Campbell et al. 2013). However the measured apparent magnitudes, have a residual scatter arising from its intrinsic scatter and effects due to line-of-sight (LOS) structures. The intrinsic scatter (∼0.4 mag) can be significantly reduced to ∼0.1 mag by empirically calibrating the luminosity curves. The scatter due to photon deflection along the LOS is composed of many different physical effects. The dominant effects are peculiar velocities at z 0.1 and gravitational lensing at z ≳ 0.3. Within the realm of cosmological perturbation theory and the stochastic nature of the LOS structures, all effects are expressed as an integral over the power spectrum with appropriate kinematical factors (Ben-Dayan et al. 2012). The lensing effects create residuals from the best-fitting curve in the magnitude–redshift relation. The lensing magnifications of SNe can be extracted by correlating the residuals with the surface densities of nearby foreground galaxies. The lensing dispersion is roughly proportional to the SNe redshift z, (e.g. Holz & Linder 2005; Ben-Dayan et al. 2013), and specifically for the concordance model, the predicted value is ∼0.06z mag.","Citation Text":["Weinberg et al. 2013"],"Citation Start End":[[502,522]]} {"Identifier":"2019ApJ...871..243YDib_et_al._2010_Instance_1","Paragraph":"There are two possibilities resulting in the different magnetic field strengths inferred from the polarimetric and molecular-line observations: (1) the rotational-to-gravitational energy βrot is overestimated, and (2) there are additional contributions in the polarized intensity from other mechanisms, such as dust scattering. In our MHD simulations, βrot is adopted to be 0.4% based on the observational estimates of the core mass of ∼1 M and the angular speed of the core rotation of 4 × 10−14 s−1. The angular speed was estimated based on the global velocity gradient along the major axis of the dense core observed with single-dish telescopes (Saito et al. 1999; Yen et al. 2011; Kurono et al. 2013). Numerical simulations of dense cores including synthetic observations show that the specific angular momentum derived from the synthetic images of the dense cores can be a factor of 8–10 higher than their actual specific angular momentum computed by the sum of the angular momenta contributed by the individual gas parcels in the dense cores (Dib et al. 2010). In addition, if there are filamentary structures in the dense core in B335, which could not be resolved with the single-dish observations, infalling motions along the filamentary structures could also contribute to the observed velocity gradient, leading to an overestimated angular speed of the core rotation (Tobin et al. 2012). We have also performed our simulations with a lower βrot, and we find that the rotational velocity on a 100 au scale in the simulations decreases with decreasing βrot. Thus, the discrepancy in the magnetic field strengths inferred from the field structures and the gas kinematics can be reconciled, if the core rotation in B335 is overestimated by a factor of a few in the observations, and these results would suggest a weak magnetic field of initial λ of 9.6 in B335. Further observations combining single dishes and interferometers to have a high spatial dynamical range and to map the velocity structures of the entire dense core in B335 at a high angular resolution are needed to study coherent velocity features and provide a better estimate of the core rotation.","Citation Text":["Dib et al. 2010"],"Citation Start End":[[1049,1064]]} {"Identifier":"2016AandA...588A...Paillou_et_al._(2008)_Instance_1","Paragraph":"H2O ice on Pluto has long escaped spectroscopic detection, and based on initial New Horizons data appears to be exposed only in a number of specific locations, usually associated with red color, suggestive of water ice\/tholin mix (Grundy et al. 2015; Cook et al. 2015). Nonetheless, water ice is likely to be ubiquitous in Pluto’s near subsurface, given its cosmogonical abundance, Pluto’s density, and its presence on Charon’s surface6. Absorption coefficients for pure water ice (kH2O) at sub-mm-to-cm wavelengths are discussed extensively by Mätzler (1998), who also provides several analytic formulations to estimate them as a function of frequency and temperature along with illustrative plots. We use the Mishima et al. (1983) formulation (see Appendix of Mätzler 1998). Its applicability is normally restricted to temperatures above 100 K, but Fig. 2 of Mätzler (1998) indicates the trend with temperature. Absorption coefficients extrapolated to 50 K (estimated as half the values at 100 K) are shown in Fig. 5. At 500 μm, our best estimate is kH2O = 0.25 cm-1, comparable to the above values for CH4 and N2 ices. The corresponding penetration length is therefore comparable to the diurnal skin depth but remains negligible compared to the seasonal skin depth, even for seasonal Γ = 25 MKS. According to these calculations, the seasonal layer would be probed only at a wavelength of ~4 mm and beyond. We also remark that the expression from Mishima et al. (1983) would give a penetration depth of 56 m at 2.2 cm, which is an order of magnitude larger than indicated by the laboratory measurements of Paillou et al. (2008). In addition, small concentrations of impurities can dramatically reduce the microwave transparency of water ice (e.g., Chyba et al. 1998 and references therein). Therefore, the above calculations likely indicate upper limits to the actual penetration depth of radiation in a H2O ice layer, from which we conclude that the seasonal layer is not reached at the Herschel wavelengths. ","Citation Text":["Paillou et al. (2008)"],"Citation Start End":[[1608,1629]]} {"Identifier":"2016AandA...588A...Grundy_et_al._2015_Instance_1","Paragraph":"H2O ice on Pluto has long escaped spectroscopic detection, and based on initial New Horizons data appears to be exposed only in a number of specific locations, usually associated with red color, suggestive of water ice\/tholin mix (Grundy et al. 2015; Cook et al. 2015). Nonetheless, water ice is likely to be ubiquitous in Pluto’s near subsurface, given its cosmogonical abundance, Pluto’s density, and its presence on Charon’s surface6. Absorption coefficients for pure water ice (kH2O) at sub-mm-to-cm wavelengths are discussed extensively by Mätzler (1998), who also provides several analytic formulations to estimate them as a function of frequency and temperature along with illustrative plots. We use the Mishima et al. (1983) formulation (see Appendix of Mätzler 1998). Its applicability is normally restricted to temperatures above 100 K, but Fig. 2 of Mätzler (1998) indicates the trend with temperature. Absorption coefficients extrapolated to 50 K (estimated as half the values at 100 K) are shown in Fig. 5. At 500 μm, our best estimate is kH2O = 0.25 cm-1, comparable to the above values for CH4 and N2 ices. The corresponding penetration length is therefore comparable to the diurnal skin depth but remains negligible compared to the seasonal skin depth, even for seasonal Γ = 25 MKS. According to these calculations, the seasonal layer would be probed only at a wavelength of ~4 mm and beyond. We also remark that the expression from Mishima et al. (1983) would give a penetration depth of 56 m at 2.2 cm, which is an order of magnitude larger than indicated by the laboratory measurements of Paillou et al. (2008). In addition, small concentrations of impurities can dramatically reduce the microwave transparency of water ice (e.g., Chyba et al. 1998 and references therein). Therefore, the above calculations likely indicate upper limits to the actual penetration depth of radiation in a H2O ice layer, from which we conclude that the seasonal layer is not reached at the Herschel wavelengths. ","Citation Text":["Grundy et al. 2015"],"Citation Start End":[[231,249]]} {"Identifier":"2015MNRAS.448.2260GHolberg_et_al._2002_Instance_1","Paragraph":"Furthermore, well-defined large samples of white dwarfs are an extremely useful starting point for identifying rare white dwarf types like magnetic white dwarfs (Gänsicke, Euchner & Jordan 2002; Schmidt et al. 2003; Külebi et al. 2009; Kepler et al. 2013), pulsating white dwarfs (Castanheira et al. 2004; Greiss et al. 2014), high\/low-mass white dwarfs (Vennes & Kawka 2008; Brown et al. 2010; Hermes et al. 2014), white dwarfs with unresolved low-mass companions (Farihi, Becklin & Zuckerman 2005; Girven et al. 2011; Steele et al. 2013), white dwarfs with rare atmospheric composition (Schmidt et al. 1999; Dufour et al. 2010; Gänsicke et al. 2010), close white dwarf binaries (Marsh, Nelemans & Steeghs 2004; Parsons et al. 2011), metal polluted white dwarfs (Sion, Leckenby & Szkody 1990; Zuckerman & Reid 1998; Dufour et al. 2007; Koester, Gänsicke & Farihi 2014) or white dwarfs with dusty or gaseous planetary debris discs (Gänsicke et al. 2006; Farihi, Jura & Zuckerman 2009; Debes et al. 2011; Wilson et al. 2014). Because of their intrinsic low luminosities identifying a large, complete and well-defined sample of white dwarfs still remains a challenge. Much progress has been made in recent years thanks to large area surveys, first and foremost the Sloan Digital Sky Survey (SDSS; York et al. 2000; Harris et al. 2003; Eisenstein et al. 2006; Kleinman et al. 2013). The largest published catalogue of white dwarfs to date (Kleinman et al. 2013) fully exploited the spectroscopic data available at the time of SDSS Data Release 7 (DR7) and contains over 20 000 white dwarfs (of which 7424 with g ≤ 19). However not only is DR7 now outdated, but SDSS spectroscopy is only available for less than 0.01 per cent of all SDSS photometric sources. Furthermore most of SDSS's white dwarfs are only serendipitous spectroscopic targets. The true potential of SDSS's vast multiband photometric coverage still remains to be fully mined for white dwarf research, but this requires a reliable method able to select white dwarfs candidates without recourse to spectroscopy. Proper motion has been traditionally used to distinguish white dwarfs from other stellar populations. In particular many studies that contributed to the census of white dwarfs in the solar neighbourhood specifically targeted high proper motion objects (Holberg et al. 2002; Sayres et al. 2012; Limoges, Lépine & Bergeron 2013). In this paper we present a novel method which makes use of photometric data and proper motions to calculate a probability of being a white dwarf (PWD) for any photometric source within a broad region in colour space. Unlike any previous similar work, our method does not use a specific cut in colour or proper motion to generate a list of white dwarf candidates; instead it provides a catalogue of sources with an associated PWD. These PWD can then be used to create samples of white dwarf candidates best suited for different specific uses. By applying our method to the full photometric footprint of SDSS Data Release 10 (DR10), we created a catalogue which includes ∼23 000 bright (g ≤ 19) high-fidelity white dwarfs candidates (Table 1). Using this catalogue, we assess the spectroscopic completeness of the SDSS white dwarf sample.","Citation Text":["Holberg et al. 2002"],"Citation Start End":[[2326,2345]]} {"Identifier":"2022ApJ...925..123NAllamandola_et_al._1989_Instance_1","Paragraph":"Benzene (C6H6), the simplest aromatic hydrocarbon, is a molecule that has raised great interest in the astrophysical community for almost four decades. This is mainly because C6H6 is one of the main precursors of polycyclic aromatic hydrocarbons (PAHs) reported to be present in interstellar dust particles (Leger & Puget 1984; Allamandola et al. 1989; Tielens 2013 and references therein), carbonaceous chondrites (Pering & Ponnamperuma 1971; Hayatsu et al. 1977; Hahn et al. 1988), and other astrophysical environments, such as carbon-rich, high-temperature environments (circumstellar and carbon-rich protoplanetary nebulae; Buss et al. 1993; Clemett et al. 1994). Benzene rings easily produce more complex, polycyclic structures by the one-ring build-up mechanism (Simoneit & Fetzer 1996). In space, an analogous process to carbon soot formation occurring on Earth can be initiated through the completion of that first aromatic ring and may also lead to the synthesis of PAHs (Tielens & Charnley 1997). Mechanisms involving the addition of hydrocarbons, such as acetylene onto aromatic rings as well as the attachment of other aromatic rings, or hydrocarbon pyrolysis, have been proposed to characterize the growth process of PAHs (Bittner & Howard 1981; Frenklach & Feigelson 1989; Wang & Frenklach 1997; Cherchneff 2011 and references therein). PAH synthesis from shocked benzene has also been reported (Mimura 1995). PAHs are crucial materials involved in a variety of cosmochemical processes. For example, amino acids could be synthesized by aqueous alteration of precursor PAHs in carbonaceous chondrites (Shock & Schulte 1990). PAHs are also produced in laboratory-simulated planetary atmospheres of Titan and Jupiter (Sagan et al. 1993; Khare et al. 2002; Trainer et al. 2004), and results from these studies indicate that the formation of aromatic rings and polyaromatics may be, among other sources, a possible chemical pathway for the production of the atmospheric solid particles (Lebonnois et al. 2002; Wilson et al. 2003; Trainer et al. 2004). The formation and evolution of benzene in planetary environments or other solar system objects thus represents a fundamental primary stage of the PAH production and other subsequent relevant chemical and prebiotic processes (like soot formation). In this context, several works related to benzene have been devoted to better understand the physico-chemical processes of irradiated C6H6, in its gaseous and solid phases, and the derived products, by acquiring high-resolution astronomical spectra, carrying out detailed laboratory studies or developing theoretical modeling (Allamandola et al. 1989 and references therein; Callahan et al. 2013; Materese et al. 2015; Mouzay et al. 2021). Laboratory astrophysical investigations have mostly focused on performing vibrational spectroscopy of ion, electron, or UV irradiated C6H6 gas and C6H6 ice. Such investigations aim to provide data on the spectral properties of the irradiated C6H6 materials, compare them with spectra obtained from astronomical observations (e.g., observations of the interstellar medium), or to study photoprocessed benzene ices to understand the fate of benzene ices in Titan’s stratosphere and help understanding the formation of aerosol analogs observed in Saturn’s moon’s stratosphere (Mouzay et al. 2021).","Citation Text":["Allamandola et al. 1989"],"Citation Start End":[[328,351]]} {"Identifier":"2022ApJ...925..123NAllamandola_et_al._1989_Instance_2","Paragraph":"Benzene (C6H6), the simplest aromatic hydrocarbon, is a molecule that has raised great interest in the astrophysical community for almost four decades. This is mainly because C6H6 is one of the main precursors of polycyclic aromatic hydrocarbons (PAHs) reported to be present in interstellar dust particles (Leger & Puget 1984; Allamandola et al. 1989; Tielens 2013 and references therein), carbonaceous chondrites (Pering & Ponnamperuma 1971; Hayatsu et al. 1977; Hahn et al. 1988), and other astrophysical environments, such as carbon-rich, high-temperature environments (circumstellar and carbon-rich protoplanetary nebulae; Buss et al. 1993; Clemett et al. 1994). Benzene rings easily produce more complex, polycyclic structures by the one-ring build-up mechanism (Simoneit & Fetzer 1996). In space, an analogous process to carbon soot formation occurring on Earth can be initiated through the completion of that first aromatic ring and may also lead to the synthesis of PAHs (Tielens & Charnley 1997). Mechanisms involving the addition of hydrocarbons, such as acetylene onto aromatic rings as well as the attachment of other aromatic rings, or hydrocarbon pyrolysis, have been proposed to characterize the growth process of PAHs (Bittner & Howard 1981; Frenklach & Feigelson 1989; Wang & Frenklach 1997; Cherchneff 2011 and references therein). PAH synthesis from shocked benzene has also been reported (Mimura 1995). PAHs are crucial materials involved in a variety of cosmochemical processes. For example, amino acids could be synthesized by aqueous alteration of precursor PAHs in carbonaceous chondrites (Shock & Schulte 1990). PAHs are also produced in laboratory-simulated planetary atmospheres of Titan and Jupiter (Sagan et al. 1993; Khare et al. 2002; Trainer et al. 2004), and results from these studies indicate that the formation of aromatic rings and polyaromatics may be, among other sources, a possible chemical pathway for the production of the atmospheric solid particles (Lebonnois et al. 2002; Wilson et al. 2003; Trainer et al. 2004). The formation and evolution of benzene in planetary environments or other solar system objects thus represents a fundamental primary stage of the PAH production and other subsequent relevant chemical and prebiotic processes (like soot formation). In this context, several works related to benzene have been devoted to better understand the physico-chemical processes of irradiated C6H6, in its gaseous and solid phases, and the derived products, by acquiring high-resolution astronomical spectra, carrying out detailed laboratory studies or developing theoretical modeling (Allamandola et al. 1989 and references therein; Callahan et al. 2013; Materese et al. 2015; Mouzay et al. 2021). Laboratory astrophysical investigations have mostly focused on performing vibrational spectroscopy of ion, electron, or UV irradiated C6H6 gas and C6H6 ice. Such investigations aim to provide data on the spectral properties of the irradiated C6H6 materials, compare them with spectra obtained from astronomical observations (e.g., observations of the interstellar medium), or to study photoprocessed benzene ices to understand the fate of benzene ices in Titan’s stratosphere and help understanding the formation of aerosol analogs observed in Saturn’s moon’s stratosphere (Mouzay et al. 2021).","Citation Text":["Allamandola et al. 1989"],"Citation Start End":[[2635,2658]]} {"Identifier":"2022ApJ...938...21MMackereth_et_al._2019_Instance_1","Paragraph":"So far, only one ancient and massive intruder has been identified unambiguously, with its body now nothing but an enormous cloud of tidal wreckage scattered throughout the inner Milky Way. The existence of a vast debris structure left behind by this merger event, known today as the Gaia-Sausage\/Enceladus (GS\/E), was suggested before Gaia (see Evans 2020, for the historical development). In particular, Deason et al. (2013) argued that the rapid transition in the Galactic stellar halo structural properties at break radius of 20–30 kpc is likely associated with the apocentric pileup of a relatively early (8–10 Gyr ago) and single massive accretion event. It is hypothesized that the progenitor dwarf galaxy was massive enough for its orbit to shrink and radialize quickly as a result of a complex interplay between dynamical deceleration, host recoiling, and self-friction (Vasiliev et al. 2022). Sinking deep in the heart of the Milky Way, the dwarf sprayed the bulk of its stars in a region enclosed by its last apocenter, i.e., some ∼30 kpc (see Deason et al. 2018). As a result, the region of the Galactic halo within this so-called break radius (see Deason et al. 2011) is inundated with the GS\/E stars, consistently showing up as the most striking substructure even in relatively small volumes around the Sun (see examples of pre-Gaia hints in, e.g., Chiba & Yoshii 1998; Brook et al. 2003; Meza et al. 2005; Nissen & Schuster 2010; Hawkins et al. 2015). Subsequently, the Gaia data made crystal clear the unusually strong radial anisotropy of the relatively metal-rich GS\/E debris and helped to reveal its dominance in the solar neighborhood (see Belokurov et al. 2018; Haywood et al. 2018b; Myeong et al. 2018b). The genesis of the GS\/E debris cloud was also unambiguously confirmed by its unique chemical fingerprint (see, e.g., Helmi et al. 2018; Mackereth et al. 2019) and the large group of globular clusters (GCs) associated with it (see, e.g., Myeong et al. 2018c, 2019; Massari et al. 2019). Close to the Sun, the GS\/E structure has been thoroughly scrutinized both kinematically and chemically (see Evans et al. 2019; Necib et al. 2019; Sahlholdt et al. 2019; Das et al. 2020; Feuillet et al. 2020, 2021; Kordopatis et al. 2020; Molaro et al. 2020; Monty et al. 2020; Aguado et al. 2021a; Buder et al. 2021a; Bonifacio et al. 2021; Carollo & Chiba 2021; Matsuno et al. 2021). Outside of the solar neighborhood, fewer studies exist; nonetheless, the global structure of the GS\/E cloud is starting to come into focus (see, e.g., Iorio & Belokurov 2019; Lancaster et al. 2019; Simion et al. 2019; Naidu et al. 2020; Balbinot & Helmi 2021; Bird et al. 2021; Iorio & Belokurov 2021; Wu et al. 2022).","Citation Text":["Mackereth et al. 2019"],"Citation Start End":[[1862,1883]]} {"Identifier":"2022ApJ...938...21MIorio_&_Belokurov_2019_Instance_1","Paragraph":"So far, only one ancient and massive intruder has been identified unambiguously, with its body now nothing but an enormous cloud of tidal wreckage scattered throughout the inner Milky Way. The existence of a vast debris structure left behind by this merger event, known today as the Gaia-Sausage\/Enceladus (GS\/E), was suggested before Gaia (see Evans 2020, for the historical development). In particular, Deason et al. (2013) argued that the rapid transition in the Galactic stellar halo structural properties at break radius of 20–30 kpc is likely associated with the apocentric pileup of a relatively early (8–10 Gyr ago) and single massive accretion event. It is hypothesized that the progenitor dwarf galaxy was massive enough for its orbit to shrink and radialize quickly as a result of a complex interplay between dynamical deceleration, host recoiling, and self-friction (Vasiliev et al. 2022). Sinking deep in the heart of the Milky Way, the dwarf sprayed the bulk of its stars in a region enclosed by its last apocenter, i.e., some ∼30 kpc (see Deason et al. 2018). As a result, the region of the Galactic halo within this so-called break radius (see Deason et al. 2011) is inundated with the GS\/E stars, consistently showing up as the most striking substructure even in relatively small volumes around the Sun (see examples of pre-Gaia hints in, e.g., Chiba & Yoshii 1998; Brook et al. 2003; Meza et al. 2005; Nissen & Schuster 2010; Hawkins et al. 2015). Subsequently, the Gaia data made crystal clear the unusually strong radial anisotropy of the relatively metal-rich GS\/E debris and helped to reveal its dominance in the solar neighborhood (see Belokurov et al. 2018; Haywood et al. 2018b; Myeong et al. 2018b). The genesis of the GS\/E debris cloud was also unambiguously confirmed by its unique chemical fingerprint (see, e.g., Helmi et al. 2018; Mackereth et al. 2019) and the large group of globular clusters (GCs) associated with it (see, e.g., Myeong et al. 2018c, 2019; Massari et al. 2019). Close to the Sun, the GS\/E structure has been thoroughly scrutinized both kinematically and chemically (see Evans et al. 2019; Necib et al. 2019; Sahlholdt et al. 2019; Das et al. 2020; Feuillet et al. 2020, 2021; Kordopatis et al. 2020; Molaro et al. 2020; Monty et al. 2020; Aguado et al. 2021a; Buder et al. 2021a; Bonifacio et al. 2021; Carollo & Chiba 2021; Matsuno et al. 2021). Outside of the solar neighborhood, fewer studies exist; nonetheless, the global structure of the GS\/E cloud is starting to come into focus (see, e.g., Iorio & Belokurov 2019; Lancaster et al. 2019; Simion et al. 2019; Naidu et al. 2020; Balbinot & Helmi 2021; Bird et al. 2021; Iorio & Belokurov 2021; Wu et al. 2022).","Citation Text":["Iorio & Belokurov 2019"],"Citation Start End":[[2548,2570]]} {"Identifier":"2017MNRAS.465..383RGaensler_et_al._2005_Instance_1","Paragraph":"In general, the Hall time-scale for magnetic field evolution depends on the strength of the magnetic field, as seen in equation (4). For young NSs with fields below 1014 G, this time-scale may be longer than the observed SNR age. Therefore, magnetic field growth does not have a dramatic effect on these young NSs. However, many of these systems are observed to have a braking index n 3 (Espinoza 2012; Archibald et al. 2016). A possible explanation for these low braking indices may be through the emission of a relativistic particle wind (Thompson & Blaes 1998; Harding, Contopoulos & Kazanas 1999; Tong et al. 2013). However, the conclusive detection of wind nebulae around magnetars in particular is challenging due to the presence of dust-scattering haloes that accompany these X-ray bright, heavily absorbed objects (Esposito et al. 2013; Safi-Harb 2013). Only a handful of such nebulae have been proposed to be associated with highly magnetized NSs. For example, a wind nebula has been proposed to surround the magnetar Swift J1834.9–0846 in W41 (Younes et al. 2016), and the luminosity of a particle wind was estimated for SGR 1806–20 based on the X-ray and radio observations of the wind-powered nebula G10.0–0.3 (Thompson & Duncan 1996; Marsden, Rothschild & Lingenfelter 1999; Gaensler et al. 2005). In the pulsar wind model, relativistic particles load the magnetosphere with charge and distort the dipole field at large scales outside of the light cylinder. Besides affecting the NS spin-down, the emission of a relativistic wind can also offer an explanation for the significant timing noise that generally affects magnetar observations (Tsang & Konstantinos 2013). The HBPs J1119–6127 and J1846–0258 are clearly associated with pulsar wind nebulae (Gavriil et al. 2008; Kumar & Safi-Harb 2008; Ng et al. 2008; Safi-Harb & Kumar 2008; Safi-Harb 2013), suggesting that particle wind emission should play an important role in their evolution. We also expect that AXP and SGR evolution may be affected by wind emission due to candidate wind nebulae, but do not consider these models for the CCOs that do not show any evidence of PWN. However, we note that braking exclusively due to a steady particle wind produces a torque with a braking index n = 1, too low for the NSs with secure SNR associations in Table 1.","Citation Text":["Gaensler et al. 2005"],"Citation Start End":[[1289,1309]]} {"Identifier":"2015ApJ...807L..14N___2013_Instance_1","Paragraph":"The de-projected distance that corresponds to the core-position changes of Markarian 421 is approximately 3.5 ∼ 8.7 pc (equivalent to (1.0 − 2.6) × 105 Schwarzschild radii (Rs)) for a jet-viewing angle of 2°–5° (Lico et al. 2012). One of the leading models for explaining the blazar phenomenon is the so-called internal-shock model, in which discrete ejecta with higher speeds catch up with the preceding slower ejecta, and the collision leads to a shock wave in the colliding ejecta (Spada et al. 2001; Guetta et al. 2004). Based on this model, core wandering can be naturally explained because the model predicts some scattering of the shock locations caused by the randomness of the ejecta speed. Therefore, we assume that the distances of the shock locations from the black hole immediately after the flare, \n\n\n\n\n\n, are proportional to the product of the square of the bulk Lorentz factor (\n\n\n\n\n\n) of the ejecta and the separation length (Δ) of the colliding ejecta. Assuming that a typical separation length is a scale of about 10 times the innermost stable circular orbit for non-rotating black holes (\n\n\n\n\n\n), in light of numerical simulations of relativistic outflows around black holes (McKinney et al. 2013), very fast ejecta with a Lorentz factor of approximately \n\n\n\n\n\n are required to explain the observed magnitude of the core wandering. The \n\n\n\n\n\n is comparable to previously reported maximum values (Γ of 40 ∼ 50; Lister et al. 2009, 2013) based on statistical studies by a long-term monitor using VLBI. Moreover, the radio core returned to the reference stationary position after 2012 March 12 (the 10th epoch). This can be explained if the emission from the reference position is identical to the radio core that is in a quiescent state. The radio-core emission in a quiescent state is expected to be persistent. As one of the possibilities for reproducing the observed core wandering, this persistent radio core was obscured by the flare-associated radio core, which therefore must be optically thick against SSA and short lived (a lifetime of approximately 2 weeks), for several epochs. Such a flare-associated radio core must be located at least \n\n\n\n\n\n downstream from the persistent radio core. In addition, Koyama et al. (2015) recently conducted multi-epoch astrometric observations of Markarian 501, which is also one of the most nearby TeV blazars by using VERA. However, they detected no significant positional changes of the radio core during its quiescent state. This fact, therefore, seems to support the radio core wandering seen after the large X-ray flare.","Citation Text":["Lister et al.","2013"],"Citation Start End":[[1430,1443],[1450,1454]]} {"Identifier":"2015ApJ...807L..14NKoyama_et_al._(2015)_Instance_1","Paragraph":"The de-projected distance that corresponds to the core-position changes of Markarian 421 is approximately 3.5 ∼ 8.7 pc (equivalent to (1.0 − 2.6) × 105 Schwarzschild radii (Rs)) for a jet-viewing angle of 2°–5° (Lico et al. 2012). One of the leading models for explaining the blazar phenomenon is the so-called internal-shock model, in which discrete ejecta with higher speeds catch up with the preceding slower ejecta, and the collision leads to a shock wave in the colliding ejecta (Spada et al. 2001; Guetta et al. 2004). Based on this model, core wandering can be naturally explained because the model predicts some scattering of the shock locations caused by the randomness of the ejecta speed. Therefore, we assume that the distances of the shock locations from the black hole immediately after the flare, \n\n\n\n\n\n, are proportional to the product of the square of the bulk Lorentz factor (\n\n\n\n\n\n) of the ejecta and the separation length (Δ) of the colliding ejecta. Assuming that a typical separation length is a scale of about 10 times the innermost stable circular orbit for non-rotating black holes (\n\n\n\n\n\n), in light of numerical simulations of relativistic outflows around black holes (McKinney et al. 2013), very fast ejecta with a Lorentz factor of approximately \n\n\n\n\n\n are required to explain the observed magnitude of the core wandering. The \n\n\n\n\n\n is comparable to previously reported maximum values (Γ of 40 ∼ 50; Lister et al. 2009, 2013) based on statistical studies by a long-term monitor using VLBI. Moreover, the radio core returned to the reference stationary position after 2012 March 12 (the 10th epoch). This can be explained if the emission from the reference position is identical to the radio core that is in a quiescent state. The radio-core emission in a quiescent state is expected to be persistent. As one of the possibilities for reproducing the observed core wandering, this persistent radio core was obscured by the flare-associated radio core, which therefore must be optically thick against SSA and short lived (a lifetime of approximately 2 weeks), for several epochs. Such a flare-associated radio core must be located at least \n\n\n\n\n\n downstream from the persistent radio core. In addition, Koyama et al. (2015) recently conducted multi-epoch astrometric observations of Markarian 501, which is also one of the most nearby TeV blazars by using VERA. However, they detected no significant positional changes of the radio core during its quiescent state. This fact, therefore, seems to support the radio core wandering seen after the large X-ray flare.","Citation Text":["Koyama et al. (2015)"],"Citation Start End":[[2230,2250]]} {"Identifier":"2016ApJ...817..117SJess_et_al._(2015)_Instance_1","Paragraph":"Running penumbral waves in velocity and intensity observations were first reported by Giovanelli (1972) and Zirin & Stein (1972). Later, they were found in the photosphere as well (Musman et al. 1976), but there they appear to be more intermittent and to have higher radial phase velocity (40–90 km s−1) than the waves in Hα. Whereas the velocity amplitudes are less in the photosphere than in the chromosphere, the density is very low there and most of the wave energy lies in the photosphere and subphotosphere. Larger amplitudes on the disk-side penumbra demonstrate an alignment of the oscillations along the magnetic field. Running waves are also detected in the umbra, but the waves were believed to be unrelated to those in the penumbra (Kobanov & Makarchik 2004). In the chromosphere, the frequency of travelling waves decreases as they propagate from the umbra into the outer penumbra (e.g., Lites 1988). A similar effect is also found in measurements of the propagation velocity of travelling waves (Brisken & Zirin 1997; Sigwarth & Mattig 1997; Alissandrakis et al. 1998; Kobanov & Makarchik 2004; Tziotziou et al. 2006, 2007). Generally, the waves decelerate from 40 km s−1 near the inner part of the penumbra to 10 km s−1 or less near the outer edge of the penumbra. More recently, from a multi-wavelength study including the coronal channels of the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO), Jess et al. (2015) revealed the presence of a wide range of frequencies, with longer periodicities preferentially occurring at increasing distance from the umbra. The phase speeds also tend to decrease with increasing periodicity as the waves propagate away from the umbral barycenter. These observations also suggest that these slow waves are driven by a regular coherent source. The physical nature of running penumbral waves has been controversial. Some researchers have regarded them as trans-sunspot waves originating from umbral oscillations since they detected waves starting from the umbra and propagating through the penumbra (e.g., Alissandrakis et al. 1992; Tsiropoula et al. 1996, 2000). However, others suggest that the trans-sunspot (i.e., outward) motion is apparent to a given line of sight, and that these oscillations actually represent the upward propagation of field-guided magnetoacoustic waves from the photosphere (e.g., Christopoulou et al. 2000, 2001; Georgakilas et al. 2000; Rouppe van der Voort et al. 2003; Bogdan & Judge 2006; Kobanov et al. 2006; Bloomfield et al. 2007; Jess et al. 2013, 2015). The gradual change in the inclination of the penumbral field lines is responsible for changes in the oscillation periods and phase speeds.","Citation Text":["Jess et al. (2015)"],"Citation Start End":[[1445,1463]]} {"Identifier":"2016ApJ...817..117SJess_et_al.___2015_Instance_2","Paragraph":"Running penumbral waves in velocity and intensity observations were first reported by Giovanelli (1972) and Zirin & Stein (1972). Later, they were found in the photosphere as well (Musman et al. 1976), but there they appear to be more intermittent and to have higher radial phase velocity (40–90 km s−1) than the waves in Hα. Whereas the velocity amplitudes are less in the photosphere than in the chromosphere, the density is very low there and most of the wave energy lies in the photosphere and subphotosphere. Larger amplitudes on the disk-side penumbra demonstrate an alignment of the oscillations along the magnetic field. Running waves are also detected in the umbra, but the waves were believed to be unrelated to those in the penumbra (Kobanov & Makarchik 2004). In the chromosphere, the frequency of travelling waves decreases as they propagate from the umbra into the outer penumbra (e.g., Lites 1988). A similar effect is also found in measurements of the propagation velocity of travelling waves (Brisken & Zirin 1997; Sigwarth & Mattig 1997; Alissandrakis et al. 1998; Kobanov & Makarchik 2004; Tziotziou et al. 2006, 2007). Generally, the waves decelerate from 40 km s−1 near the inner part of the penumbra to 10 km s−1 or less near the outer edge of the penumbra. More recently, from a multi-wavelength study including the coronal channels of the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO), Jess et al. (2015) revealed the presence of a wide range of frequencies, with longer periodicities preferentially occurring at increasing distance from the umbra. The phase speeds also tend to decrease with increasing periodicity as the waves propagate away from the umbral barycenter. These observations also suggest that these slow waves are driven by a regular coherent source. The physical nature of running penumbral waves has been controversial. Some researchers have regarded them as trans-sunspot waves originating from umbral oscillations since they detected waves starting from the umbra and propagating through the penumbra (e.g., Alissandrakis et al. 1992; Tsiropoula et al. 1996, 2000). However, others suggest that the trans-sunspot (i.e., outward) motion is apparent to a given line of sight, and that these oscillations actually represent the upward propagation of field-guided magnetoacoustic waves from the photosphere (e.g., Christopoulou et al. 2000, 2001; Georgakilas et al. 2000; Rouppe van der Voort et al. 2003; Bogdan & Judge 2006; Kobanov et al. 2006; Bloomfield et al. 2007; Jess et al. 2013, 2015). The gradual change in the inclination of the penumbral field lines is responsible for changes in the oscillation periods and phase speeds.","Citation Text":["Jess et al.","2015"],"Citation Start End":[[2547,2558],[2565,2569]]} {"Identifier":"2021ApJ...921..179LTan_et_al._2010_Instance_1","Paragraph":"Quasi-periodic pulsations (QPPs) often refer to the quasi-periodic intensity variations during solar\/stellar flares (see Zimovets et al. 2021, for a recent review). In many observations, the flare QPPs were found to show a nonstationary property in the time series integrated over the whole Sun\/star or over the oscillation region, for instance, each pulsation has an anharmonic and symmetric triangular profile shape (e.g., Kolotkov et al. 2015; Nakariakov et al. 2019). The signature of flare QPPs can be detected in flare light curves across a broad band of the electromagnetic spectrum, i.e., radio\/microwave emissions (Ning et al. 2005; Reznikova & Shibasaki 2011; Nakariakov et al. 2018; Yu & Chen 2019), UV\/EUV wavelengths (Shen et al. 2018; Hayes et al. 2019; Reeves et al. 2020; Miao et al. 2021), SXR\/HXR and γ-ray channels (Nakariakov et al. 2010; Ning 2017; Hayes et al. 2020; Li et al. 2020c), and the Hα (Srivastava et al. 2008; Kashapova et al. 2020; Li et al. 2020b) or Lyα (Van Doorsselaere et al. 2011; Milligan et al. 2017; Li 2021) emissions. The quasi-periods of these QPPs were reported from subseconds to tens of minutes (e.g., Tan et al. 2010; Shen et al. 2013, 2019; Kolotkov et al. 2018; Karlický & Rybák 2020; Clarke et al. 2021). It should be stated that the observed periods are generally related to the specific channels or flare phases (Tian et al. 2016; Dennis et al. 2017; Pugh et al. 2019), suggesting that the various classes of QPPs could be produced by different generation mechanisms (e.g., Kupriyanova et al. 2020). In the literature, the flare-related QPPs were most often explained by magnetohydrodynamic (MHD) waves, more specifically sausage waves, kink waves, and slow waves (Li et al. 2020a; Nakariakov & Kolotkov 2020; Wang et al. 2021), or by a repetitive regime of magnetic reconnection that could be spontaneous (i.e., self-oscillatory process) or triggered owing to external MHD oscillations (Thurgood et al. 2017; Yuan et al. 2019; Clarke et al. 2021). They can also be interpreted in terms of the LRC-circuit oscillation in current-carrying loops (Tan et al. 2016; Li et al. 2020b) or caused by the interaction between supra-arcade downflows and flare loops (Xue et al. 2020; Samanta et al. 2021).","Citation Text":["Tan et al. 2010"],"Citation Start End":[[1151,1166]]} {"Identifier":"2016MNRAS.461..666KGoyal_et_al._2013_Instance_1","Paragraph":"C-statistic (e.g. Jang & Miller 1997) is the most commonly used and the one-way analysis of variance (ANOVA; de Diego 2010) the most powerful test for verifying the presence of variability in a DLC. However, we did not employ either of these tests because, de Diego (2010) has questioned the validity of the C-test by arguing that the C-statistics does not have a Gaussian distribution and the commonly used critical value of 2.567 is too conservative. On the other hand, the ANOVA test requires a rather large number of data points in the DLC, so as to have several points within each sub-group used for the analysis. This is not feasible for our DLCs which typically have no more than about 30–45 data points. Therefore, we have instead used the F-test which is based on the ratio of variances, F = variance(observed)\/variance(expected) (de Diego 2010; Villforth, Koekemoer & Grogin 2010), with its two versions : (i) the standard F-test (hereafter Fη-test, Goyal et al. 2012) and (ii) scaled F-test (hereafter Fκ-test, Joshi et al. 2011). The Fκ-test is preferred when the magnitude difference between the object and comparison stars is large (Joshi et al. 2011). Onward Paper II, we have only been using the Fη-test because our objects are generally quite comparable in brightness to their available comparison stars. An additional gain from the use of the Fη-test is that we can directly compare our INOV results with those deduced for other major AGN classes (Goyal et al. 2013). An important point to keep in mind while applying the statistical tests is that the photometric errors on individual data points in a given DLC, as returned by the algorithms in the iraf and daophot softwares are normally underestimated by the factor η which ranges between 1.3 and 1.75, as estimated in independent studies (e.g. Gopal-Krishna, Sagar & Wiita 1995; Garcia et al. 1999; Sagar et al. 2004; Stalin et al. 2004a; Bachev, Strigachev & Semkov 2005). Recently, using a large sample, Goyal et al. (2013) estimated the best-fitting value of η to be 1.5, which is adopted here. Thus, the Fη statistics can be expressed as\n\n\n\\begin{equation*}\nF_{1}^{\\eta } = \\frac{\\sigma ^{2}_{({\\rm q-s1})}}{ \\eta ^2 \\langle \\sigma _{{\\rm q-s1}}^2 \\rangle }, \\hspace{5.69046pt} F_{2}^{\\eta } = \\frac{\\sigma ^{2}_{({\\rm q-s2})}}{ \\eta ^2 \\langle \\sigma _{{\\rm q-s2}}^2 \\rangle }, \\hspace{5.69046pt} F_{{\\rm s1-s2}}^{\\eta } = \\frac{\\sigma ^{2}_{({\\rm s1-s2})}}{ \\eta ^2 \\langle \\sigma _{{\\rm s1-s2}}^2 \\rangle },\\end{equation*}\n\n where $\\sigma ^{2}_{({\\rm q-s1})}$, $\\sigma ^{2}_{({\\rm q-s2})}$ and $\\sigma ^{2}_{({\\rm s1-s2})}$ are the variances of the ‘quasar–star1’, ‘quasar–star2’ and ‘star1–star2’ DLCs and $\\langle \\sigma _{{\\rm q-s1}}^2 \\rangle =\\sum _{\\boldsymbol {i}=0}^{N}\\sigma ^2_{i,{\\rm err}}({\\rm q-s1})\/N$, $\\langle \\sigma _{{\\rm q-s2}}^2 \\rangle$ and $\\langle \\sigma _{{\\rm s1-s2}}^2 \\rangle$ are the mean square (formal) rms errors of the individual data points in the ‘quasar–star1’, ‘quasar–star2’ and ‘star1–star2’ DLCs, respectively. η is the scaling factor (= 1.5) as mentioned above.","Citation Text":["Goyal et al. 2013"],"Citation Start End":[[1466,1483]]} {"Identifier":"2016MNRAS.461..666KGoyal_et_al._(2013)_Instance_2","Paragraph":"C-statistic (e.g. Jang & Miller 1997) is the most commonly used and the one-way analysis of variance (ANOVA; de Diego 2010) the most powerful test for verifying the presence of variability in a DLC. However, we did not employ either of these tests because, de Diego (2010) has questioned the validity of the C-test by arguing that the C-statistics does not have a Gaussian distribution and the commonly used critical value of 2.567 is too conservative. On the other hand, the ANOVA test requires a rather large number of data points in the DLC, so as to have several points within each sub-group used for the analysis. This is not feasible for our DLCs which typically have no more than about 30–45 data points. Therefore, we have instead used the F-test which is based on the ratio of variances, F = variance(observed)\/variance(expected) (de Diego 2010; Villforth, Koekemoer & Grogin 2010), with its two versions : (i) the standard F-test (hereafter Fη-test, Goyal et al. 2012) and (ii) scaled F-test (hereafter Fκ-test, Joshi et al. 2011). The Fκ-test is preferred when the magnitude difference between the object and comparison stars is large (Joshi et al. 2011). Onward Paper II, we have only been using the Fη-test because our objects are generally quite comparable in brightness to their available comparison stars. An additional gain from the use of the Fη-test is that we can directly compare our INOV results with those deduced for other major AGN classes (Goyal et al. 2013). An important point to keep in mind while applying the statistical tests is that the photometric errors on individual data points in a given DLC, as returned by the algorithms in the iraf and daophot softwares are normally underestimated by the factor η which ranges between 1.3 and 1.75, as estimated in independent studies (e.g. Gopal-Krishna, Sagar & Wiita 1995; Garcia et al. 1999; Sagar et al. 2004; Stalin et al. 2004a; Bachev, Strigachev & Semkov 2005). Recently, using a large sample, Goyal et al. (2013) estimated the best-fitting value of η to be 1.5, which is adopted here. Thus, the Fη statistics can be expressed as\n\n\n\\begin{equation*}\nF_{1}^{\\eta } = \\frac{\\sigma ^{2}_{({\\rm q-s1})}}{ \\eta ^2 \\langle \\sigma _{{\\rm q-s1}}^2 \\rangle }, \\hspace{5.69046pt} F_{2}^{\\eta } = \\frac{\\sigma ^{2}_{({\\rm q-s2})}}{ \\eta ^2 \\langle \\sigma _{{\\rm q-s2}}^2 \\rangle }, \\hspace{5.69046pt} F_{{\\rm s1-s2}}^{\\eta } = \\frac{\\sigma ^{2}_{({\\rm s1-s2})}}{ \\eta ^2 \\langle \\sigma _{{\\rm s1-s2}}^2 \\rangle },\\end{equation*}\n\n where $\\sigma ^{2}_{({\\rm q-s1})}$, $\\sigma ^{2}_{({\\rm q-s2})}$ and $\\sigma ^{2}_{({\\rm s1-s2})}$ are the variances of the ‘quasar–star1’, ‘quasar–star2’ and ‘star1–star2’ DLCs and $\\langle \\sigma _{{\\rm q-s1}}^2 \\rangle =\\sum _{\\boldsymbol {i}=0}^{N}\\sigma ^2_{i,{\\rm err}}({\\rm q-s1})\/N$, $\\langle \\sigma _{{\\rm q-s2}}^2 \\rangle$ and $\\langle \\sigma _{{\\rm s1-s2}}^2 \\rangle$ are the mean square (formal) rms errors of the individual data points in the ‘quasar–star1’, ‘quasar–star2’ and ‘star1–star2’ DLCs, respectively. η is the scaling factor (= 1.5) as mentioned above.","Citation Text":["Goyal et al. (2013)"],"Citation Start End":[[1978,1997]]} {"Identifier":"2015MNRAS.448..666SDyson_&_Williams_1980_Instance_1","Paragraph":"In local galaxies, the ISM conditions are often described by some physical quantities such as ionization parameter (q), gaseous metallicity (Z) and electron density (ne). At high redshift, the ionization parameter is raised by a large flux of ionizing photons in ISM originated from hot O, B stars due to intensive star formation in relatively small galaxies. Previous studies suggest a high ionization parameter of SF galaxies at z > 2 compared to that of local galaxies (Erb et al. 2010; Nakajima et al. 2013; Masters et al. 2014; Nakajima & Ouchi 2014). Secondly, the chemical abundance of SF galaxies at z ∼ 2 is lower by 0.1–0.3 dex for a given stellar mass compared to those at low-z (Erb et al. 2006a; Sanders et al. 2014; Steidel et al. 2014). This leads to more compact and hotter O, B stars due to lower opacity (Ezer & Cameron 1971; Maeder 1987), and thus UV radiation becomes harder and produces more ionizing photons. Thirdly, the strength of collisionally excited emission lines (e.g. [O iii], [N ii]) strongly depends on the electron density. It is closely related to the number of electrons to collide since the excitation potential of this line is ∼1 eV, which is nearly the same as the energy of electrons at the virial temperature (∼104 K) (Dyson & Williams 1980). Due to low excitation potential, the transition of collisionally excited line is reliant on electron density compared to gaseous metallicity. Recent observations have suggested a high electron density (ne > 100 cm−3) in SF galaxies at z ∼ 2 (Newman et al. 2012; Masters et al. 2014; Shirazi, Brinchmann & Rahmati 2014; Wuyts et al. 2014). This value is larger than that of normal SF galaxies at low-z by an order of magnitude, and close to that of interacting galaxies which are seen as (ultra)luminous infrared (IR) galaxies in the present-day Universe (Krabbe et al. 2014). Such a large electron density contributes to the offset of galaxy distributions on the BPT diagram together with other physical parameters (Brinchmann, Pettini & Charlot 2008a). In this way, the cosmic dependence of the BPT diagram can be attributed to such physical parameters which determine ISM conditions.","Citation Text":["Dyson & Williams 1980"],"Citation Start End":[[1260,1281]]} {"Identifier":"2015MNRAS.448..666SNewman_et_al._2012_Instance_1","Paragraph":"In local galaxies, the ISM conditions are often described by some physical quantities such as ionization parameter (q), gaseous metallicity (Z) and electron density (ne). At high redshift, the ionization parameter is raised by a large flux of ionizing photons in ISM originated from hot O, B stars due to intensive star formation in relatively small galaxies. Previous studies suggest a high ionization parameter of SF galaxies at z > 2 compared to that of local galaxies (Erb et al. 2010; Nakajima et al. 2013; Masters et al. 2014; Nakajima & Ouchi 2014). Secondly, the chemical abundance of SF galaxies at z ∼ 2 is lower by 0.1–0.3 dex for a given stellar mass compared to those at low-z (Erb et al. 2006a; Sanders et al. 2014; Steidel et al. 2014). This leads to more compact and hotter O, B stars due to lower opacity (Ezer & Cameron 1971; Maeder 1987), and thus UV radiation becomes harder and produces more ionizing photons. Thirdly, the strength of collisionally excited emission lines (e.g. [O iii], [N ii]) strongly depends on the electron density. It is closely related to the number of electrons to collide since the excitation potential of this line is ∼1 eV, which is nearly the same as the energy of electrons at the virial temperature (∼104 K) (Dyson & Williams 1980). Due to low excitation potential, the transition of collisionally excited line is reliant on electron density compared to gaseous metallicity. Recent observations have suggested a high electron density (ne > 100 cm−3) in SF galaxies at z ∼ 2 (Newman et al. 2012; Masters et al. 2014; Shirazi, Brinchmann & Rahmati 2014; Wuyts et al. 2014). This value is larger than that of normal SF galaxies at low-z by an order of magnitude, and close to that of interacting galaxies which are seen as (ultra)luminous infrared (IR) galaxies in the present-day Universe (Krabbe et al. 2014). Such a large electron density contributes to the offset of galaxy distributions on the BPT diagram together with other physical parameters (Brinchmann, Pettini & Charlot 2008a). In this way, the cosmic dependence of the BPT diagram can be attributed to such physical parameters which determine ISM conditions.","Citation Text":["Newman et al. 2012"],"Citation Start End":[[1526,1544]]} {"Identifier":"2015MNRAS.448..666SKrabbe_et_al._2014_Instance_1","Paragraph":"In local galaxies, the ISM conditions are often described by some physical quantities such as ionization parameter (q), gaseous metallicity (Z) and electron density (ne). At high redshift, the ionization parameter is raised by a large flux of ionizing photons in ISM originated from hot O, B stars due to intensive star formation in relatively small galaxies. Previous studies suggest a high ionization parameter of SF galaxies at z > 2 compared to that of local galaxies (Erb et al. 2010; Nakajima et al. 2013; Masters et al. 2014; Nakajima & Ouchi 2014). Secondly, the chemical abundance of SF galaxies at z ∼ 2 is lower by 0.1–0.3 dex for a given stellar mass compared to those at low-z (Erb et al. 2006a; Sanders et al. 2014; Steidel et al. 2014). This leads to more compact and hotter O, B stars due to lower opacity (Ezer & Cameron 1971; Maeder 1987), and thus UV radiation becomes harder and produces more ionizing photons. Thirdly, the strength of collisionally excited emission lines (e.g. [O iii], [N ii]) strongly depends on the electron density. It is closely related to the number of electrons to collide since the excitation potential of this line is ∼1 eV, which is nearly the same as the energy of electrons at the virial temperature (∼104 K) (Dyson & Williams 1980). Due to low excitation potential, the transition of collisionally excited line is reliant on electron density compared to gaseous metallicity. Recent observations have suggested a high electron density (ne > 100 cm−3) in SF galaxies at z ∼ 2 (Newman et al. 2012; Masters et al. 2014; Shirazi, Brinchmann & Rahmati 2014; Wuyts et al. 2014). This value is larger than that of normal SF galaxies at low-z by an order of magnitude, and close to that of interacting galaxies which are seen as (ultra)luminous infrared (IR) galaxies in the present-day Universe (Krabbe et al. 2014). Such a large electron density contributes to the offset of galaxy distributions on the BPT diagram together with other physical parameters (Brinchmann, Pettini & Charlot 2008a). In this way, the cosmic dependence of the BPT diagram can be attributed to such physical parameters which determine ISM conditions.","Citation Text":["Krabbe et al. 2014"],"Citation Start End":[[1839,1857]]} {"Identifier":"2021MNRAS.506..813D__Krajnović_et_al._2006_Instance_1","Paragraph":"The kinematic analysis was performed by using the selected sample of stars in the MUSE catalogue (see Section 3) and by following the maximum-likelihood approach described by Pryor & Meylan (1993). The method is based on the assumption that the probability of finding a star with a velocity of vi ± ϵi at a projected distance from the cluster centre Ri can be approximated as \n(1)$$\\begin{eqnarray*}\r\np(v_i,\\epsilon _i,R_i) = \\frac{1}{2\\pi \\sqrt{\\sigma ^2 + \\epsilon _i^2}}exp{\\frac{(v_i-v_0)^2}{-2\\left(\\sigma ^2 + \\epsilon _i^2\\right)}}\r\n\\end{eqnarray*}$$where v0 and σ are the systemic radial velocity and the intrinsic dispersion profile of the cluster, respectively. Rotation was included in the analysis by adding the following angular dependence (e.g. Copin et al. 2001; Krajnović et al. 2006; Kamann et al. 2018a) to the mean velocity of equation (1). \n(2)$$\\begin{eqnarray*}\r\nv_0 = v_0 + v_{rot}(R_i)sin(\\theta _i - \\theta _0(R_i))\r\n\\end{eqnarray*}$$where vrot and θ0 represent the projected rotation velocity and the rotation axis angle respectively as a function of the projected distance R to the cluster centre. The axis angle as well as the position angle θi of a star are measured from north through east. We restricted the prior for θ0 to a 180° wide interval and we allowed the rotation velocity to assume both positive and negative values, in order to avoid a skewed rotation velocity probability distribution in case of very small or no rotation (see also Kamann et al. 2020). In particular, we used an iterative procedure in which we adopted an angular interval [α; α + 180°) centred on the most probable rotation axis angle. This is useful to avoid skewness in the probability distribution of θ0 when its value is close to 0° or 180°. We split the sample in five concentric annuli centred on the cluster centre and with width varying in such a way that each bin contains the same number of stars (80). Only stars with r 32 arcsec were considered in the analysis as they guarantee an almost complete coverage within each annulus (Fig. 1).","Citation Text":["Krajnović et al. 2006"],"Citation Start End":[[778,799]]} {"Identifier":"2021MNRAS.506..813DPryor_&_Meylan_(1993)_Instance_1","Paragraph":"The kinematic analysis was performed by using the selected sample of stars in the MUSE catalogue (see Section 3) and by following the maximum-likelihood approach described by Pryor & Meylan (1993). The method is based on the assumption that the probability of finding a star with a velocity of vi ± ϵi at a projected distance from the cluster centre Ri can be approximated as \n(1)$$\\begin{eqnarray*}\r\np(v_i,\\epsilon _i,R_i) = \\frac{1}{2\\pi \\sqrt{\\sigma ^2 + \\epsilon _i^2}}exp{\\frac{(v_i-v_0)^2}{-2\\left(\\sigma ^2 + \\epsilon _i^2\\right)}}\r\n\\end{eqnarray*}$$where v0 and σ are the systemic radial velocity and the intrinsic dispersion profile of the cluster, respectively. Rotation was included in the analysis by adding the following angular dependence (e.g. Copin et al. 2001; Krajnović et al. 2006; Kamann et al. 2018a) to the mean velocity of equation (1). \n(2)$$\\begin{eqnarray*}\r\nv_0 = v_0 + v_{rot}(R_i)sin(\\theta _i - \\theta _0(R_i))\r\n\\end{eqnarray*}$$where vrot and θ0 represent the projected rotation velocity and the rotation axis angle respectively as a function of the projected distance R to the cluster centre. The axis angle as well as the position angle θi of a star are measured from north through east. We restricted the prior for θ0 to a 180° wide interval and we allowed the rotation velocity to assume both positive and negative values, in order to avoid a skewed rotation velocity probability distribution in case of very small or no rotation (see also Kamann et al. 2020). In particular, we used an iterative procedure in which we adopted an angular interval [α; α + 180°) centred on the most probable rotation axis angle. This is useful to avoid skewness in the probability distribution of θ0 when its value is close to 0° or 180°. We split the sample in five concentric annuli centred on the cluster centre and with width varying in such a way that each bin contains the same number of stars (80). Only stars with r 32 arcsec were considered in the analysis as they guarantee an almost complete coverage within each annulus (Fig. 1).","Citation Text":["Pryor & Meylan (1993)"],"Citation Start End":[[175,196]]} {"Identifier":"2017MNRAS.471.2848LYuan_et_al._2015_Instance_1","Paragraph":"For LLAGNs, there are two competing components for the emission at optical\/UV wavebands. One component is the thermal emission from the outer truncated SSD, which peaks in optical or UV bands, depending on the location of the truncated radius. The other component is the Compton scattering of synchrotron emission from the inner hot accretion flow (Manmoto et al. 1997; Yuan & Narayan 2014). Since our sample is limited to sources whose λ 10−3, we argue that the emission at 2500 Å mainly comes from the inner hot accretion flow.3 Interestingly, for hot accretion flows around supermassive BHs (the LLAGN case), the optical\/UV emission usually is the first Compton up-scattered bump (Manmoto et al. 1997; Yuan & Narayan 2014). The emission from such a process has a positive correlation with $\\dot{m}$, as $\\dot{m}$ will mainly determine the optical depth (surface density), a quantity that controls the probability of Compton scattering (Sunyaev & Titarchuk 1980; Dermer, Liang & Canfield 1991). On the other hand, the first Compton bump is even more sensitive to the energy of electrons (a.k.a. the electron temperature), as it determines the location (in wavebands) of the peak. For a given $\\dot{m}$, larger α means lower density, or equivalently lower radiative cooling to the electrons. Consequently, the electrons will be more energetic at higher temperatures (Xie & Yuan 2012). The dependence of emission at optical\/UV band on the parameter α relies on detailed numerical calculations, where Manmoto et al. (1997) reported that the emission at 2500 Å has a positive correlation with α. For the above reasons, we simply write LUV as\n(6)\r\n\\begin{equation}\r\nL_{\\rm UV}\\sim (\\dot{m} \\alpha )^b,\r\n\\end{equation}\r\nwhere b ∼ 2. The estimation of b comes from the fact that the first-order Compton scattering (responsible for the optical\/UV emission) depends on the product of the seed photon flux (synchrotron emission, $\\propto \\dot{m}^{0.5-1}$; cf. Mahadevan 1997; Yuan et al. 2015; note that electron temperature also depends on $\\dot{m}$ for the expression in Mahadevan 1997) and optical depth in a vertical direction ($\\propto \\dot{m}^{1-2}$).","Citation Text":["Yuan et al. 2015"],"Citation Start End":[[1969,1985]]} {"Identifier":"2019ApJ...883...53TAnderson_et_al._2018_Instance_1","Paragraph":"LISA Pathfinder (LPF; Antonucci et al. 2011), a European Space Agency (ESA) mission that operated near the first Sun–Earth Lagrange point (L1) from 2016 January through 2017 July, is in an ideal orbit to make such measurements. However, LPF flew no instrumentation dedicated to micrometeoroid or dust detection. LPF’s primary objective was to demonstrate technologies for a future space-based observatory of millihertz-band gravitational waves. The key achievement of LPF was placing two gold-platinum cubes known as “test masses” into a freefall so pure that it was characterized by accelerations at the femto-g level (e.g., Armano et al. 2016, 2018b), the level required to detect the minute disturbances caused by passing gravitational waves. In order to reach this level of performance, the test masses were released into cavities inside the spacecraft and a control system was employed to keep the spacecraft centered on the test masses. This control system was designed to counteract disturbances on the spacecraft, including those caused by impacts from micrometeoroids. Shortly before LPF’s launch, it was realized that data from the control system, if properly calibrated, could be used to detect and characterize these impacts and infer information about the impacting particles (e.g., Thorpe et al. 2016). While such impact events have been reported by other spacecraft, LPF’s unique instrumentation makes it sensitive to much smaller and much more numerous impacts and allows the impact geometry to be more fully constrained. Early results from the first few months of LPF operations suggested that such events could indeed be identified and were roughly consistent with the pre-launch predictions of their effect on the control system (e.g., Thorpe et al. 2017). In this paper we present results from the first systematic search for micrometeoroid impacts in the LPF data set. Our data set consists of 4348 hr of data in both the nominal LPF configuration and the “Disturbance Reduction System” (DRS) configuration, in which a NASA-supplied controller and thruster system took over control of the spacecraft (Anderson et al. 2018). Our data set corresponds to the times when LPF was operating in a “quiet” mode, without any intentional signal injections or other disturbances. During this period, we have identified 54 impact candidates using our detection pipeline and manual vetoing. We have characterized the properties of this data set and compared it to several theoretical models for the underlying dust population.","Citation Text":["Anderson et al. 2018"],"Citation Start End":[[2122,2142]]} {"Identifier":"2019ApJ...883...53TThorpe_et_al._2016_Instance_1","Paragraph":"LISA Pathfinder (LPF; Antonucci et al. 2011), a European Space Agency (ESA) mission that operated near the first Sun–Earth Lagrange point (L1) from 2016 January through 2017 July, is in an ideal orbit to make such measurements. However, LPF flew no instrumentation dedicated to micrometeoroid or dust detection. LPF’s primary objective was to demonstrate technologies for a future space-based observatory of millihertz-band gravitational waves. The key achievement of LPF was placing two gold-platinum cubes known as “test masses” into a freefall so pure that it was characterized by accelerations at the femto-g level (e.g., Armano et al. 2016, 2018b), the level required to detect the minute disturbances caused by passing gravitational waves. In order to reach this level of performance, the test masses were released into cavities inside the spacecraft and a control system was employed to keep the spacecraft centered on the test masses. This control system was designed to counteract disturbances on the spacecraft, including those caused by impacts from micrometeoroids. Shortly before LPF’s launch, it was realized that data from the control system, if properly calibrated, could be used to detect and characterize these impacts and infer information about the impacting particles (e.g., Thorpe et al. 2016). While such impact events have been reported by other spacecraft, LPF’s unique instrumentation makes it sensitive to much smaller and much more numerous impacts and allows the impact geometry to be more fully constrained. Early results from the first few months of LPF operations suggested that such events could indeed be identified and were roughly consistent with the pre-launch predictions of their effect on the control system (e.g., Thorpe et al. 2017). In this paper we present results from the first systematic search for micrometeoroid impacts in the LPF data set. Our data set consists of 4348 hr of data in both the nominal LPF configuration and the “Disturbance Reduction System” (DRS) configuration, in which a NASA-supplied controller and thruster system took over control of the spacecraft (Anderson et al. 2018). Our data set corresponds to the times when LPF was operating in a “quiet” mode, without any intentional signal injections or other disturbances. During this period, we have identified 54 impact candidates using our detection pipeline and manual vetoing. We have characterized the properties of this data set and compared it to several theoretical models for the underlying dust population.","Citation Text":["Thorpe et al. 2016"],"Citation Start End":[[1296,1314]]} {"Identifier":"2019ApJ...883...53TThorpe_et_al._2017_Instance_1","Paragraph":"LISA Pathfinder (LPF; Antonucci et al. 2011), a European Space Agency (ESA) mission that operated near the first Sun–Earth Lagrange point (L1) from 2016 January through 2017 July, is in an ideal orbit to make such measurements. However, LPF flew no instrumentation dedicated to micrometeoroid or dust detection. LPF’s primary objective was to demonstrate technologies for a future space-based observatory of millihertz-band gravitational waves. The key achievement of LPF was placing two gold-platinum cubes known as “test masses” into a freefall so pure that it was characterized by accelerations at the femto-g level (e.g., Armano et al. 2016, 2018b), the level required to detect the minute disturbances caused by passing gravitational waves. In order to reach this level of performance, the test masses were released into cavities inside the spacecraft and a control system was employed to keep the spacecraft centered on the test masses. This control system was designed to counteract disturbances on the spacecraft, including those caused by impacts from micrometeoroids. Shortly before LPF’s launch, it was realized that data from the control system, if properly calibrated, could be used to detect and characterize these impacts and infer information about the impacting particles (e.g., Thorpe et al. 2016). While such impact events have been reported by other spacecraft, LPF’s unique instrumentation makes it sensitive to much smaller and much more numerous impacts and allows the impact geometry to be more fully constrained. Early results from the first few months of LPF operations suggested that such events could indeed be identified and were roughly consistent with the pre-launch predictions of their effect on the control system (e.g., Thorpe et al. 2017). In this paper we present results from the first systematic search for micrometeoroid impacts in the LPF data set. Our data set consists of 4348 hr of data in both the nominal LPF configuration and the “Disturbance Reduction System” (DRS) configuration, in which a NASA-supplied controller and thruster system took over control of the spacecraft (Anderson et al. 2018). Our data set corresponds to the times when LPF was operating in a “quiet” mode, without any intentional signal injections or other disturbances. During this period, we have identified 54 impact candidates using our detection pipeline and manual vetoing. We have characterized the properties of this data set and compared it to several theoretical models for the underlying dust population.","Citation Text":["Thorpe et al. 2017"],"Citation Start End":[[1755,1773]]} {"Identifier":"2020MNRAS.496.2000C__Mihalas_&_Mihalas_1984_Instance_1","Paragraph":"Since Colgate & White (1966) proposed that neutrinos play a crucial role in reviving the stalled shock in core-collapse supernovae (CCSNe), numerical models have incorporated neutrino transport in some form, with varying degrees of sophistication. The neutrino transport problem in CCSNe poses one of the most computationally challenging problems to date. The extreme range in densities within the supernova results in optically thick regions in which neutrinos are diffusive, and optically thin regions in which neutrinos are decoupled from the fluid and can stream freely. The so-called gain region behind the stalled shock, which the success of the explosion hinges upon, lies within the semitransparent region between the two regimes, where an accurate treatment of the neutrino distribution function is important (for modern reviews of the topic, see Mezzacappa 2005; Janka 2012; Burrows 2013). The most accurate treatment of neutrino transport calls for the solution of the full Boltzmann equation (Mihalas & Mihalas 1984),\n(1)$$\\begin{eqnarray*}\r\n\\frac{\\partial f}{\\partial t} + \\boldsymbol {u} \\cdot \\nabla f = \\mathcal {C}(f),\r\n\\end{eqnarray*}$$(shown here the Newtonian form for clarity) which describes the neutrino momentum distribution f at every point in space (Fig. 1). Evolving through time, this results in a 7D problem. The left-hand side of the equation is the advection equation, which couples together the spatial dimensions. The right-hand side contains the collision integral, which accounts for interactions between neutrinos and matter, and couple together the momentum space dimensions. Interaction rates are sensitive to the neutrino energy, necessitating an energy-dependent treatment. Additionally, there are three flavors of neutrinos (electron, muon, and tauon) and respective antineutrinos for a total of six species. Due to the different interaction rates of each species, their transport behaviour is considerably different, thus the core-collapse problem also calls for a flavour-dependent treatment. In general, even flavour can evolve via neutrino oscillations, a purely quantum mechanical effect (Wolfenstein 1978; Mikheyev & Smirnov 1985).","Citation Text":["Mihalas & Mihalas 1984"],"Citation Start End":[[1005,1027]]} {"Identifier":"2020MNRAS.496.2000CColgate_&_White_(1966)_Instance_1","Paragraph":"Since Colgate & White (1966) proposed that neutrinos play a crucial role in reviving the stalled shock in core-collapse supernovae (CCSNe), numerical models have incorporated neutrino transport in some form, with varying degrees of sophistication. The neutrino transport problem in CCSNe poses one of the most computationally challenging problems to date. The extreme range in densities within the supernova results in optically thick regions in which neutrinos are diffusive, and optically thin regions in which neutrinos are decoupled from the fluid and can stream freely. The so-called gain region behind the stalled shock, which the success of the explosion hinges upon, lies within the semitransparent region between the two regimes, where an accurate treatment of the neutrino distribution function is important (for modern reviews of the topic, see Mezzacappa 2005; Janka 2012; Burrows 2013). The most accurate treatment of neutrino transport calls for the solution of the full Boltzmann equation (Mihalas & Mihalas 1984),\n(1)$$\\begin{eqnarray*}\r\n\\frac{\\partial f}{\\partial t} + \\boldsymbol {u} \\cdot \\nabla f = \\mathcal {C}(f),\r\n\\end{eqnarray*}$$(shown here the Newtonian form for clarity) which describes the neutrino momentum distribution f at every point in space (Fig. 1). Evolving through time, this results in a 7D problem. The left-hand side of the equation is the advection equation, which couples together the spatial dimensions. The right-hand side contains the collision integral, which accounts for interactions between neutrinos and matter, and couple together the momentum space dimensions. Interaction rates are sensitive to the neutrino energy, necessitating an energy-dependent treatment. Additionally, there are three flavors of neutrinos (electron, muon, and tauon) and respective antineutrinos for a total of six species. Due to the different interaction rates of each species, their transport behaviour is considerably different, thus the core-collapse problem also calls for a flavour-dependent treatment. In general, even flavour can evolve via neutrino oscillations, a purely quantum mechanical effect (Wolfenstein 1978; Mikheyev & Smirnov 1985).","Citation Text":["Colgate & White (1966)"],"Citation Start End":[[6,28]]} {"Identifier":"2016ApJ...830...56J__Norton_et_al._1996_Instance_1","Paragraph":"We have carried out analyses of X-ray and optical photometric data of an MCV Paloma. Using the X-ray data from XMM-Newton, we derive 10 significant periods in Paloma, including two fundamental periods of 156 ± 1 minutes and 130 ± 1 minutes. However, using our optical data, we derive seven significant periods in which \n\n\n\n\n\n and \n\n\n\n\n\n are consistent with ∼1.5σ level to that derived from X-ray data. The peaks corresponding to the frequencies Ω, ω, \n\n\n\n\n\n, and \n\n\n\n\n\n are well matched with those derived by Schwarz et al. (2007). The orbital modulation in the X-ray light curves is generally explained by the absorption of X-rays emitted near the WD surface by material fixed in the orbital frame, but a strong signal at the orbital period in the X-ray power spectra of Paloma indicates that an explicit orbital modulation is most likely due to the attenuation introduced by the impact site of the accretion stream with the accretion disk or magnetosphere. On the other hand, X-ray modulation at the spin period can arise due to the self-occultation of emission regions by the WD or due to photoelectric absorption and electron scattering in the accretion curtain (Norton et al. 1996). The occurrence of the spin peak indicates that the symmetry of the two pole caps is broken and the amount of asymmetry depends on whether the signal corresponding to the rotation of the asymmetrically placed pole is strong or weak, i.e., the degree of asymmetry is proportional to the power of the spin peak (Wynn & King 1992). Along with the spin frequency, the presence of significant peaks in the X-ray power spectrum at ω − Ω, Ω, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n also predict that Paloma is an asymmetric system in which both the emission poles are not diametrically opposite and have slightly different emission properties (see Norton et al. 1996). Furthermore, the presence of significant power at spin, beat and \n\n\n\n\n\n frequencies suggest that Paloma is a disk-less accreting system (see Wynn & King 1992; Norton et al. 1996). Additionally, an increase in power of the beat or \n\n\n\n\n\n components accompanied by the decrease in power at the spin component as the X-ray energy increases is a characteristic of the disk-less accretion. This is clearly visible in the X-ray power density spectra of Paloma, which is further attributed to the absorption of low-energy photons by the accretion column itself. Other than the orbital, spin, and beat periods, photometric observations of Paloma show peaks at frequencies \n\n\n\n\n\n and \n\n\n\n\n\n. Such similar positive and negative sideband frequencies corresponding to the spin and orbital periods are also observed from photometric observations in nearly synchronous IP V697 Sco (Warner & Woudt 2002), suggesting that Paloma may have a close resemblance to V697 Sco.","Citation Text":["Norton et al. 1996"],"Citation Start End":[[1167,1185]]} {"Identifier":"2016ApJ...830...56J__Norton_et_al._1996_Instance_2","Paragraph":"We have carried out analyses of X-ray and optical photometric data of an MCV Paloma. Using the X-ray data from XMM-Newton, we derive 10 significant periods in Paloma, including two fundamental periods of 156 ± 1 minutes and 130 ± 1 minutes. However, using our optical data, we derive seven significant periods in which \n\n\n\n\n\n and \n\n\n\n\n\n are consistent with ∼1.5σ level to that derived from X-ray data. The peaks corresponding to the frequencies Ω, ω, \n\n\n\n\n\n, and \n\n\n\n\n\n are well matched with those derived by Schwarz et al. (2007). The orbital modulation in the X-ray light curves is generally explained by the absorption of X-rays emitted near the WD surface by material fixed in the orbital frame, but a strong signal at the orbital period in the X-ray power spectra of Paloma indicates that an explicit orbital modulation is most likely due to the attenuation introduced by the impact site of the accretion stream with the accretion disk or magnetosphere. On the other hand, X-ray modulation at the spin period can arise due to the self-occultation of emission regions by the WD or due to photoelectric absorption and electron scattering in the accretion curtain (Norton et al. 1996). The occurrence of the spin peak indicates that the symmetry of the two pole caps is broken and the amount of asymmetry depends on whether the signal corresponding to the rotation of the asymmetrically placed pole is strong or weak, i.e., the degree of asymmetry is proportional to the power of the spin peak (Wynn & King 1992). Along with the spin frequency, the presence of significant peaks in the X-ray power spectrum at ω − Ω, Ω, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n also predict that Paloma is an asymmetric system in which both the emission poles are not diametrically opposite and have slightly different emission properties (see Norton et al. 1996). Furthermore, the presence of significant power at spin, beat and \n\n\n\n\n\n frequencies suggest that Paloma is a disk-less accreting system (see Wynn & King 1992; Norton et al. 1996). Additionally, an increase in power of the beat or \n\n\n\n\n\n components accompanied by the decrease in power at the spin component as the X-ray energy increases is a characteristic of the disk-less accretion. This is clearly visible in the X-ray power density spectra of Paloma, which is further attributed to the absorption of low-energy photons by the accretion column itself. Other than the orbital, spin, and beat periods, photometric observations of Paloma show peaks at frequencies \n\n\n\n\n\n and \n\n\n\n\n\n. Such similar positive and negative sideband frequencies corresponding to the spin and orbital periods are also observed from photometric observations in nearly synchronous IP V697 Sco (Warner & Woudt 2002), suggesting that Paloma may have a close resemblance to V697 Sco.","Citation Text":["Norton et al. 1996"],"Citation Start End":[[1847,1865]]} {"Identifier":"2016ApJ...830...56J__Norton_et_al._1996_Instance_3","Paragraph":"We have carried out analyses of X-ray and optical photometric data of an MCV Paloma. Using the X-ray data from XMM-Newton, we derive 10 significant periods in Paloma, including two fundamental periods of 156 ± 1 minutes and 130 ± 1 minutes. However, using our optical data, we derive seven significant periods in which \n\n\n\n\n\n and \n\n\n\n\n\n are consistent with ∼1.5σ level to that derived from X-ray data. The peaks corresponding to the frequencies Ω, ω, \n\n\n\n\n\n, and \n\n\n\n\n\n are well matched with those derived by Schwarz et al. (2007). The orbital modulation in the X-ray light curves is generally explained by the absorption of X-rays emitted near the WD surface by material fixed in the orbital frame, but a strong signal at the orbital period in the X-ray power spectra of Paloma indicates that an explicit orbital modulation is most likely due to the attenuation introduced by the impact site of the accretion stream with the accretion disk or magnetosphere. On the other hand, X-ray modulation at the spin period can arise due to the self-occultation of emission regions by the WD or due to photoelectric absorption and electron scattering in the accretion curtain (Norton et al. 1996). The occurrence of the spin peak indicates that the symmetry of the two pole caps is broken and the amount of asymmetry depends on whether the signal corresponding to the rotation of the asymmetrically placed pole is strong or weak, i.e., the degree of asymmetry is proportional to the power of the spin peak (Wynn & King 1992). Along with the spin frequency, the presence of significant peaks in the X-ray power spectrum at ω − Ω, Ω, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n also predict that Paloma is an asymmetric system in which both the emission poles are not diametrically opposite and have slightly different emission properties (see Norton et al. 1996). Furthermore, the presence of significant power at spin, beat and \n\n\n\n\n\n frequencies suggest that Paloma is a disk-less accreting system (see Wynn & King 1992; Norton et al. 1996). Additionally, an increase in power of the beat or \n\n\n\n\n\n components accompanied by the decrease in power at the spin component as the X-ray energy increases is a characteristic of the disk-less accretion. This is clearly visible in the X-ray power density spectra of Paloma, which is further attributed to the absorption of low-energy photons by the accretion column itself. Other than the orbital, spin, and beat periods, photometric observations of Paloma show peaks at frequencies \n\n\n\n\n\n and \n\n\n\n\n\n. Such similar positive and negative sideband frequencies corresponding to the spin and orbital periods are also observed from photometric observations in nearly synchronous IP V697 Sco (Warner & Woudt 2002), suggesting that Paloma may have a close resemblance to V697 Sco.","Citation Text":["Norton et al. 1996"],"Citation Start End":[[2027,2045]]} {"Identifier":"2016ApJ...830...56JWarner_&_Woudt_2002_Instance_1","Paragraph":"We have carried out analyses of X-ray and optical photometric data of an MCV Paloma. Using the X-ray data from XMM-Newton, we derive 10 significant periods in Paloma, including two fundamental periods of 156 ± 1 minutes and 130 ± 1 minutes. However, using our optical data, we derive seven significant periods in which \n\n\n\n\n\n and \n\n\n\n\n\n are consistent with ∼1.5σ level to that derived from X-ray data. The peaks corresponding to the frequencies Ω, ω, \n\n\n\n\n\n, and \n\n\n\n\n\n are well matched with those derived by Schwarz et al. (2007). The orbital modulation in the X-ray light curves is generally explained by the absorption of X-rays emitted near the WD surface by material fixed in the orbital frame, but a strong signal at the orbital period in the X-ray power spectra of Paloma indicates that an explicit orbital modulation is most likely due to the attenuation introduced by the impact site of the accretion stream with the accretion disk or magnetosphere. On the other hand, X-ray modulation at the spin period can arise due to the self-occultation of emission regions by the WD or due to photoelectric absorption and electron scattering in the accretion curtain (Norton et al. 1996). The occurrence of the spin peak indicates that the symmetry of the two pole caps is broken and the amount of asymmetry depends on whether the signal corresponding to the rotation of the asymmetrically placed pole is strong or weak, i.e., the degree of asymmetry is proportional to the power of the spin peak (Wynn & King 1992). Along with the spin frequency, the presence of significant peaks in the X-ray power spectrum at ω − Ω, Ω, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n also predict that Paloma is an asymmetric system in which both the emission poles are not diametrically opposite and have slightly different emission properties (see Norton et al. 1996). Furthermore, the presence of significant power at spin, beat and \n\n\n\n\n\n frequencies suggest that Paloma is a disk-less accreting system (see Wynn & King 1992; Norton et al. 1996). Additionally, an increase in power of the beat or \n\n\n\n\n\n components accompanied by the decrease in power at the spin component as the X-ray energy increases is a characteristic of the disk-less accretion. This is clearly visible in the X-ray power density spectra of Paloma, which is further attributed to the absorption of low-energy photons by the accretion column itself. Other than the orbital, spin, and beat periods, photometric observations of Paloma show peaks at frequencies \n\n\n\n\n\n and \n\n\n\n\n\n. Such similar positive and negative sideband frequencies corresponding to the spin and orbital periods are also observed from photometric observations in nearly synchronous IP V697 Sco (Warner & Woudt 2002), suggesting that Paloma may have a close resemblance to V697 Sco.","Citation Text":["Warner & Woudt 2002"],"Citation Start End":[[2736,2755]]} {"Identifier":"2020ApJ...896L..21RLamperti_et_al._2020_Instance_1","Paragraph":"Top left: the revised, CO(J = 1 → 0)-based Mgas from VLASPECS confirm that z = 2–3 galaxies detected in the ASPECS survey (green circles; tentative detections are marked with a plus sign) closely follow the “star formation law” (i.e., Mgas–SFR relation) at high redshift. CO-detected main-sequence galaxies at similar redshifts from the PHIBBS1\/2 surveys (typically based on CO J = 3 → 2, but using a metallicity-dependent conversion factor; Tacconi et al. 2018) and local galaxies from the xCOLD GASS CO(J = 1 → 0) survey (Saintonge et al. 2017) are shown for comparison. Bottom left: same as the top left panel, but plotting the depletion time tdep against Mgas. All samples cover a similar range in tdep, but the average tdep for the (higher Mgas) high-z samples appear lower. Top right: the r31 brightness temperature ratio of VLASPECS galaxies (green circles) is similar to that of strongly lensed z ∼ 3 Lyman-break galaxies (red triangles; Riechers et al. 2010), z > 2 main-sequence galaxies from the PHIBSS survey (gray crosses; Bolatto et al. 2015), and z > 2 dusty star-forming galaxies (DSFGs; blue squares; compilation from Sharon et al. 2016; including data from Danielson et al. 2011; Ivison et al. 2011; Riechers et al. 2011a, 2011b, 2013; Thomson et al. 2012; Fu et al. 2013; Sharon et al. 2013, 2015; other DSFGs shown as light gray squares are from Nayyeri et al. 2017; Dannerbauer et al. 2019; Harrington et al. 2019; Leung et al. 2019; Sharon et al. 2019) and clustered DSFGs (dark gray squares; Bussmann et al. 2015; Gómez-Guijarro et al. 2019), but ∼2 times higher on average than BzK-selected main-sequence galaxies at z ∼ 1.5 (magenta crosses; Daddi et al. 2015). Nearby galaxy samples from the xCOLD GASS survey (Lamperti et al. 2020) and two studies of infrared-luminous galaxies (Yao et al. 2003; Papadopoulos et al. 2012) are shown for comparison. Dashed lines and shaded regions indicate mean\/median values and spread for high-z samples with >2 galaxies or clusters, with the same color coding as the symbols. Dashed–dotted lines indicate mean values for the low-z samples. Bottom right: same as the top right panel, but shown as binned histograms in r31 (excluding upper limits) and across the full redshift range, and only including samples for which mean\/median values are indicated in the top right panels.","Citation Text":["Lamperti et al. 2020"],"Citation Start End":[[1737,1757]]} {"Identifier":"2020AandA...635A.18Fukazawa_et_al._2016_Instance_1","Paragraph":"Two additional interesting sources for a comparison are the radio galaxies M 87 (z = 0.0044) and 3C 84 (also called NGC 1275, z = 0.0176). Both sources have a viewing angle similar to NGC 3894: 15°  θ   25° (Mertens et al. 2016) and θ   18° (Giovannini et al. 2018), respectively. The velocities of the jet components are about 0.2c in 3C 84 (Suzuki et al. 2012) and in the inner part of M 87 (Mertens et al. 2016), similar to what we find for NGC 3894. The three sources have a comparable photon index (Γ ∼ 2.1). Although it is less distant and more extended (∼100 kpc), M 87 shows a γ-ray luminosity of 6−7 × 1041 erg s−1, similar to NGC 3894. Different is the case of 3C 84, which has two-sided compact (parsec scale) jets and a distance similar to NGC 3894, but it presents a γ-ray luminosity more than 200 times higher (2 × 1044 erg s−1). Unlike NGC 3894, for which no observations with Cherenkov telescopes have been performed, M 87 and 3C 84 are also detected at very high energy (VHE, E > 100 GeV; Aharonian et al. 2006; Aleksić et al. 2012). In particular, at VHE, M 87 displayed strong variability on timescales as short as one day, but no unique signature of the region responsible for the VHE flares has been identified (Abramowski et al. 2012). Despite the long-term monitoring of M 87 during 2012−2015 in a low-activity state, the production site of γ-rays remains unclear (MAGIC Collaboration 2020). However, the correlation observed between the radio and X-ray activities is a strong indication that most often the emitting region is close to the core in this source. In the case of 3C 84, several works on radio, X-ray, and γ-ray variability suggest that short-term and long-term variability may be produced in different regions of the source. In particular, short-term variability seems related to the injection of fresh particles that are accelerated in a shock in the core region, whereas long-term variability is more likely connected with the jet structure (e.g., Fukazawa et al. 2016; Hodgson et al. 2018). Similarly to M 87 and 3C 84, long-term radio and X-ray monitoring of NGC 3894 may provide important information about the origin of the γ-ray emission.","Citation Text":["Fukazawa et al. 2016"],"Citation Start End":[[1986,2006]]} {"Identifier":"2022ApJ...930...70HChen_et_al._(2020)_Instance_1","Paragraph":"There are some existing studies applying machine learning to transient studies. For example, the spectral types of the SNe can be classified based on their light-curve data (Möller et al. 2016; Muthukrishna et al. 2019a; Takahashi et al. 2020; Villar et al. 2020), and transients can be identified from the astronomical survey images (Goldstein et al. 2015; Mahabal et al. 2019; Gómez et al. 2020). The light curves of SNe Ia can be well modeled by functional principal component analysis (FPCA; He et al. 2018), where it was shown remarkably that a set of FPCA eigenvectors that are independent of the photometric filters can be derived from the observed light curves of SNe Ia. There are a few studies of the application of deep learning neural networks to the spectral data of SNe. For example, Muthukrishna et al. (2019b) used a convolutional neural network (CNN) for automated SN type classification based on SN spectra. Several other works (Chen et al. 2020; Vogl et al. 2020; Kerzendorf et al. 2021) applied a Gaussian process, principal component analysis (PCA), and deep learning neural networks to radiative transfer models of SNe. Sasdelli et al. (2016) used unsupervised learning algorithms to investigate the subtypes of SNe Ia. Stahl et al. (2020) developed neural networks to predict the photometric properties of SNe Ia (phase and Δm\n15) based on spectroscopic data. Saunders et al. (2018) used PCA to find low dimensional representations of the spectral sequences of 140 well-observed SNe Ia. Chen et al. (2020), in particular, built an artificial intelligence assisted inversion (AIAI) of radiative transfer models and used that to link the observed SN spectra with theoretical models. The AIAI is able to retrieve the elemental abundances and density and temperature profiles from observed SN spectra. The AIAI approach has the potential for quantitatively coupling complex theoretical models with the ever-increasing amount of high-quality observational data.","Citation Text":["Chen et al. (2020)"],"Citation Start End":[[1510,1528]]} {"Identifier":"2020MNRAS.499.1918B__Gräfener,_Koesterke_&_Hamann_2002_Instance_1","Paragraph":"The strength of emission features scales not only with the mass-loss rate but also with the volume-filling factor (fv), terminal velocity, and radius of the star which are compressed into one parameter to reduce the effort when computing model grids. There are two ways to spectroscopically quantify mass-loss rates of hot massive stars using scaling relations. Stars with optically thin winds (OB stars), the wind strength parameter Q is usually applied (Puls et al. 1996; Sabín-Sanjulián et al. 2014, 2017; Holgado et al. 2018), where Q is proportional to the integrated optical depth over the resonance zone:\n(1)$$\\begin{eqnarray*}\r\nQ=\\frac{\\dot{M}\\, [\\mathrm{ M}_{\\odot }\\mathrm{yr}^{-1}]\/\\sqrt{f_{\\rm v}}}{(R\\, [R_{\\odot }] \\upsilon _{\\infty }\\, [\\mathrm{km\\,s^{-1}}])^{3\/2}},\r\n\\end{eqnarray*}$$and fV has been set to unity (see Section 4.3). For optically thick conditions, there is an additional dependence on $\\upsilon _{\\infty }$ (e.g. Puls et al. 1996). The transformed radius (Schmutz, Hamann & Wessolowski 1989; Gräfener, Koesterke & Hamann 2002; Hamann & Gräfener 2004) or the equivalent approach of the transformed mass-loss rate ($\\dot{M}_{\\rm t}$, Bestenlehner et al. 2014) is usually used for optically thick winds (WR stars), where the line equivalent width is preserved:\n(2)$$\\begin{eqnarray*}\r\n\\log (\\dot{M}) &=& \\log (\\dot{M}_{\\rm t}) + 0.5\\log (f_{\\rm v}) + \\log \\left(\\frac{\\upsilon _{\\infty }}{1000\\, \\mathrm{km\\, s}^{-1}} \\right) \\nonumber \\\\\r\n&&+ \\,0.75\\log \\left(\\frac{L}{10^6L_{\\odot }} \\right).\r\n\\end{eqnarray*}$$Both scaling relations are equivalent except for the exponent of the $\\upsilon _{\\infty }$ dependence, $\\dot{M} \\varpropto\\upsilon _{\\infty }^{3\/2}$ (wind strength Q), and $\\dot{M} \\varpropto\\upsilon _{\\infty }$ (transformed mass-loss rate $\\dot{M}_{\\mathrm{t}}$). In our study, we compared both scaling relations and find that optically thin winds are preferably scaled with the wind strength parameter while optically thick winds are better scaled with the transformed mass-loss rate. If $\\upsilon _{\\infty }$ in the model has a reasonable value, the differences between both scaling relations are small. However, if the line is in emission and the terminal velocity of the synthetic spectrum is too high, the line centre is fitted well with the Q scaling relation, but the synthetic spectrum shows extended wings. This overestimates the actual mass-loss rate. By fitting Balmer lines in absorption, a degeneracy between log g and $\\dot{M}$ can occur using the $\\dot{M}_{\\mathrm{t}}$ scaling relation. We used the $\\dot{M}_{\\mathrm{t}}$ scaling relation for R136a1, a2, a3, a5, b, and H36 and Q for the remaining O stars in our sample.","Citation Text":["Gräfener, Koesterke & Hamann 2002"],"Citation Start End":[[1024,1057]]} {"Identifier":"2020MNRAS.499.1918BPuls_et_al._1996_Instance_1","Paragraph":"The strength of emission features scales not only with the mass-loss rate but also with the volume-filling factor (fv), terminal velocity, and radius of the star which are compressed into one parameter to reduce the effort when computing model grids. There are two ways to spectroscopically quantify mass-loss rates of hot massive stars using scaling relations. Stars with optically thin winds (OB stars), the wind strength parameter Q is usually applied (Puls et al. 1996; Sabín-Sanjulián et al. 2014, 2017; Holgado et al. 2018), where Q is proportional to the integrated optical depth over the resonance zone:\n(1)$$\\begin{eqnarray*}\r\nQ=\\frac{\\dot{M}\\, [\\mathrm{ M}_{\\odot }\\mathrm{yr}^{-1}]\/\\sqrt{f_{\\rm v}}}{(R\\, [R_{\\odot }] \\upsilon _{\\infty }\\, [\\mathrm{km\\,s^{-1}}])^{3\/2}},\r\n\\end{eqnarray*}$$and fV has been set to unity (see Section 4.3). For optically thick conditions, there is an additional dependence on $\\upsilon _{\\infty }$ (e.g. Puls et al. 1996). The transformed radius (Schmutz, Hamann & Wessolowski 1989; Gräfener, Koesterke & Hamann 2002; Hamann & Gräfener 2004) or the equivalent approach of the transformed mass-loss rate ($\\dot{M}_{\\rm t}$, Bestenlehner et al. 2014) is usually used for optically thick winds (WR stars), where the line equivalent width is preserved:\n(2)$$\\begin{eqnarray*}\r\n\\log (\\dot{M}) &=& \\log (\\dot{M}_{\\rm t}) + 0.5\\log (f_{\\rm v}) + \\log \\left(\\frac{\\upsilon _{\\infty }}{1000\\, \\mathrm{km\\, s}^{-1}} \\right) \\nonumber \\\\\r\n&&+ \\,0.75\\log \\left(\\frac{L}{10^6L_{\\odot }} \\right).\r\n\\end{eqnarray*}$$Both scaling relations are equivalent except for the exponent of the $\\upsilon _{\\infty }$ dependence, $\\dot{M} \\varpropto\\upsilon _{\\infty }^{3\/2}$ (wind strength Q), and $\\dot{M} \\varpropto\\upsilon _{\\infty }$ (transformed mass-loss rate $\\dot{M}_{\\mathrm{t}}$). In our study, we compared both scaling relations and find that optically thin winds are preferably scaled with the wind strength parameter while optically thick winds are better scaled with the transformed mass-loss rate. If $\\upsilon _{\\infty }$ in the model has a reasonable value, the differences between both scaling relations are small. However, if the line is in emission and the terminal velocity of the synthetic spectrum is too high, the line centre is fitted well with the Q scaling relation, but the synthetic spectrum shows extended wings. This overestimates the actual mass-loss rate. By fitting Balmer lines in absorption, a degeneracy between log g and $\\dot{M}$ can occur using the $\\dot{M}_{\\mathrm{t}}$ scaling relation. We used the $\\dot{M}_{\\mathrm{t}}$ scaling relation for R136a1, a2, a3, a5, b, and H36 and Q for the remaining O stars in our sample.","Citation Text":["Puls et al. 1996"],"Citation Start End":[[456,472]]} {"Identifier":"2022MNRAS.515...71SGraham_et_al._2014_Instance_1","Paragraph":"\nSteady and smooth decline: Since falling from the peak of the 2012b event, SN 2009ip has only continued to fade and is now the faintest it has ever been in the optical. Immediately after the 2012 event (around day 200), it was declining somewhat slower than the rate of 56Co decay for a 56Ni mass of 0.04 $\\, {\\rm M}_{\\odot }$ (shown by the dashed grey line in Fig. 2). During that time, its light curve and spectral properties were consistent with those of late-time SNe IIn, and it had an underlying broad-line spectrum similar to that of SN 1987A (Graham et al. 2014; Smith et al. 2014). Up to about day 1000 it continued to fade smoothly at a slower rate around 0.003 mag d−1, and spectroscopically it continued to resemble late-time interaction in SNe IIn (Fox et al. 2015; Smith et al. 2016b; Graham et al. 2017). Our new HST photometry shows that from about day 1000 to day 3000, SN 2009ip has continued to fade smoothly and steadily in the optical, at an even slower rate. While the HST cadence is obviously sparse at these late times, the filters with more than two observations (F555W and F814W) show no significant deviation from a steady decline; there is no evidence of any rebrightening or irregularity in the fading rate. From 2015 to 2021, the decline rates in the various optical filters are 0.00051 ± 0.00001 mag d−1 in F555W, 0.00068 ± 0.00002 mag d−1 in F606W, 0.00092 ± 0.00001 mag d−1 in F657N, and 0.00050 ± 0.00001 mag d−1 in F814W. (The UV is an exception, as discussed below.) While this decline is much slower than radioactive decay, such slow decline rates are not at all unusual for SNe IIn with late-time CSM interaction. SNe IIn span a wide diversity of late-time decay rates, ranging from some SNe IIn that have essentially flat light curves for many years, like SN 2005ip (Smith et al. 2009, 2017; Stritzinger et al. 2012; Fox et al. 2020), down to those that have only weak CSM interaction and faster decline rates that are difficult to distinguish from radioactive decay or light echoes. Some SNe IIn even rebrighten at late times, like SN 2006jd (Stritzinger et al. 2012). In any case, it seems as if SN 2009ip is levelling off and approaching a constant V absolute magnitude of −7.5 or so. In all three broad continuum filters, the object is now fainter than the progenitor, and the light curve has not exhibited any additional eruptive variability since the 2012b event.","Citation Text":["Graham et al. 2014"],"Citation Start End":[[552,570]]} {"Identifier":"2021ApJ...914..131YBlandford_&_Znajek_1977_Instance_1","Paragraph":"Let us first define some terminology before describing our results. “Outflow” means the flow with a positive radial velocity vr, including both “turbulent outflow” and “real outflow.” In the former case, the test particle will first move outward but will eventually return after moving outward for some distance. In the latter case, the test particle continues to flow outward and eventually escapes the outer boundary of the simulation domain. “Real outflow” consists of two components, i.e., jet and wind. The jet region is defined as the region occupied by the time-averaged magnetic field lines connected to the ergosphere (described by \n\n\n\n\n\n\nr\n\n\nerg\n\n\n≡\n\n\nr\n\n\ng\n\n\n+\n\n\n1\n−\n\n\na\n\n\n2\n\n\n\n\ncos\n\n\n2\n\n\nθ\n\n\n\n\n\nr\n\n\ng\n\n\n;\n\n\n Visser 2007) of the black hole. We note that this definition coincides with other notions of the jet based on velocity and magnetization, as seen even in early two-dimensional simulations (McKinney & Gammie 2004). Moreover, turbulence tends not to have a strong effect on these field lines, so that in both individual snapshots and a time-averaged sense, the field lines connecting to the ergosphere coincide with β 2 and σ > 1 (McKinney et al. 2012, see Figures 3 and 6). Thus, the jet region is bounded by the magnetic field line whose foot point is rooted at the black hole ergosphere with θ = 90°, i.e., the boundary between the black hole ergosphere and the accretion flow (refer to the red lines in Figure 5). In this case, all magnetic field lines in the jet region are anchored to the black hole ergosphere and thus can extract the spin energy of the black hole via the Blandford & Znajek mechanism (Blandford & Znajek 1977; hereafter BZ77) to power the jet (“BZ-jet”). Real outflows outside of this boundary are powered by the rotation energy of the accretion flow, and we call them wind. Note that our definition of wind adopted here is different from that adopted in some literature, where they require that the Bernoulli parameter of wind must satisfy Be > 0. We do not add this requirement because we find that for a nonsteady accretion flow, Be is not constant along the trajectories but usually increases outward, at least to the radius within which turbulence is well developed (Yuan et al. 2015). We find that even though Be is negative at a small radius, it can become positive when it propagates outward.","Citation Text":["Blandford & Znajek 1977"],"Citation Start End":[[1629,1652]]} {"Identifier":"2021ApJ...914..131YYuan_et_al._2015_Instance_1","Paragraph":"Let us first define some terminology before describing our results. “Outflow” means the flow with a positive radial velocity vr, including both “turbulent outflow” and “real outflow.” In the former case, the test particle will first move outward but will eventually return after moving outward for some distance. In the latter case, the test particle continues to flow outward and eventually escapes the outer boundary of the simulation domain. “Real outflow” consists of two components, i.e., jet and wind. The jet region is defined as the region occupied by the time-averaged magnetic field lines connected to the ergosphere (described by \n\n\n\n\n\n\nr\n\n\nerg\n\n\n≡\n\n\nr\n\n\ng\n\n\n+\n\n\n1\n−\n\n\na\n\n\n2\n\n\n\n\ncos\n\n\n2\n\n\nθ\n\n\n\n\n\nr\n\n\ng\n\n\n;\n\n\n Visser 2007) of the black hole. We note that this definition coincides with other notions of the jet based on velocity and magnetization, as seen even in early two-dimensional simulations (McKinney & Gammie 2004). Moreover, turbulence tends not to have a strong effect on these field lines, so that in both individual snapshots and a time-averaged sense, the field lines connecting to the ergosphere coincide with β 2 and σ > 1 (McKinney et al. 2012, see Figures 3 and 6). Thus, the jet region is bounded by the magnetic field line whose foot point is rooted at the black hole ergosphere with θ = 90°, i.e., the boundary between the black hole ergosphere and the accretion flow (refer to the red lines in Figure 5). In this case, all magnetic field lines in the jet region are anchored to the black hole ergosphere and thus can extract the spin energy of the black hole via the Blandford & Znajek mechanism (Blandford & Znajek 1977; hereafter BZ77) to power the jet (“BZ-jet”). Real outflows outside of this boundary are powered by the rotation energy of the accretion flow, and we call them wind. Note that our definition of wind adopted here is different from that adopted in some literature, where they require that the Bernoulli parameter of wind must satisfy Be > 0. We do not add this requirement because we find that for a nonsteady accretion flow, Be is not constant along the trajectories but usually increases outward, at least to the radius within which turbulence is well developed (Yuan et al. 2015). We find that even though Be is negative at a small radius, it can become positive when it propagates outward.","Citation Text":["Yuan et al. 2015"],"Citation Start End":[[2216,2232]]} {"Identifier":"2017ApJ...850...97BChristensen_et_al._2012_Instance_1","Paragraph":"The H i mass fraction of every gas particle in the baryonic runs is calculated based on the particle’s temperature and density and the cosmic UV background radiation flux while including a prescription for self-shielding of H2 and dust shielding in both H i and H2 (Christensen et al. 2012). This allows for the straightforward calculation of the total H i mass of each simulated galaxy. We create mock H i data cubes only for the 42 halos that contain \n\n\n\n\n\n. Specifically, we create mock data cubes that mimic ALFALFA observations (Haynes et al. 2011). After specifying a viewing angle (see below), our code considers the line-of-sight velocity of each gas particle. The velocity of each particle is tracked in the simulation by solving Newton’s equations of motion, but any turbulent velocity of the gas is not taken into account. Velocity dispersions in dwarf galaxies can be on the order of the rotational velocity, ∼10–15 km s−1 (e.g., Stanimirović et al. 2004; Tamburro et al. 2009; Oh et al. 2015). Dispersions are thought to be driven at least partially by thermal velocities or supernovae (Tamburro et al. 2009; Stilp et al. 2013a, 2013b). In our simulations, supernovae inject thermal energy, and the thermal state of the H i gas needs to be considered in the mock H i linewidth for a realistic comparison to observations. To account for the thermal velocity, the H i mass of each gas particle is assumed to be distributed along the line-of-sight in a Gaussian distribution with a standard deviation given by the thermal velocity dispersion, \n\n\n\n\n\n, where T is the temperature of the gas particle. After this thermal broadening is calculated, a mock H i data cube can be generated by specifying the spatial and velocity resolution. For all of our galaxies, we adopt a spatial resolution of 54 pixels across 2Rvir. In practice, this corresponds to a range of ∼1 kpc resolution in our lowest-mass galaxies up to ∼9 kpc resolution in our most massive galaxies. However, the spatial resolution plays no role in our study, since measurements of the VF are based on spatially unresolved H i data. For the velocity resolution, we match the ALFALFA specification of 11.2 km s−1 (two-channel boxcar-smoothed).","Citation Text":["Christensen et al. 2012"],"Citation Start End":[[266,289]]} {"Identifier":"2017ApJ...850...97BStilp_et_al._2013a_Instance_1","Paragraph":"The H i mass fraction of every gas particle in the baryonic runs is calculated based on the particle’s temperature and density and the cosmic UV background radiation flux while including a prescription for self-shielding of H2 and dust shielding in both H i and H2 (Christensen et al. 2012). This allows for the straightforward calculation of the total H i mass of each simulated galaxy. We create mock H i data cubes only for the 42 halos that contain \n\n\n\n\n\n. Specifically, we create mock data cubes that mimic ALFALFA observations (Haynes et al. 2011). After specifying a viewing angle (see below), our code considers the line-of-sight velocity of each gas particle. The velocity of each particle is tracked in the simulation by solving Newton’s equations of motion, but any turbulent velocity of the gas is not taken into account. Velocity dispersions in dwarf galaxies can be on the order of the rotational velocity, ∼10–15 km s−1 (e.g., Stanimirović et al. 2004; Tamburro et al. 2009; Oh et al. 2015). Dispersions are thought to be driven at least partially by thermal velocities or supernovae (Tamburro et al. 2009; Stilp et al. 2013a, 2013b). In our simulations, supernovae inject thermal energy, and the thermal state of the H i gas needs to be considered in the mock H i linewidth for a realistic comparison to observations. To account for the thermal velocity, the H i mass of each gas particle is assumed to be distributed along the line-of-sight in a Gaussian distribution with a standard deviation given by the thermal velocity dispersion, \n\n\n\n\n\n, where T is the temperature of the gas particle. After this thermal broadening is calculated, a mock H i data cube can be generated by specifying the spatial and velocity resolution. For all of our galaxies, we adopt a spatial resolution of 54 pixels across 2Rvir. In practice, this corresponds to a range of ∼1 kpc resolution in our lowest-mass galaxies up to ∼9 kpc resolution in our most massive galaxies. However, the spatial resolution plays no role in our study, since measurements of the VF are based on spatially unresolved H i data. For the velocity resolution, we match the ALFALFA specification of 11.2 km s−1 (two-channel boxcar-smoothed).","Citation Text":["Stilp et al. 2013a"],"Citation Start End":[[1122,1140]]} {"Identifier":"2021MNRAS.507.1229PClocchiatti_&_Wheeler_1997_Instance_1","Paragraph":"In this work, we present well-calibrated optical photometric (−0.2 to +413 d), polarimetric (−2 to +31 d) and optical (−5 to +391 d), NIR (−5 to +22 d) spectroscopic studies of SN 2012au, based on data obtained using many observational facilities around the globe. Analysis based on our photometric observations suggests that SN 2012au appears to be one of the most luminous SNe Ib (MB, peak = −18.06 ± 0.12 mag), though fainter than the threshold limit of SLSNe I (M$_\\mathrm{ g}\\, \\lt -$19.8 mag; Quimby et al. 2018). The MR, peak (∼ –18.67 ± 0.11 mag) of SN 2012au is brighter than the average values of SNe Ib and Ic, but closer to those reported for SNe Ic-BL (Drout et al. 2011). Similarly, the peak bolometric luminosity of SN 2012au (∼ [6.56 ± 0.70] × 1042 erg s−1) is higher than the mean peak luminosities of SNe Ib and Ic, but still lower than those of SNe Ic-BL (Lyman et al. 2016). Using the early bolometric light curve of SN 2012au, the estimated values of Mej, Ek, MNi, and T0 are ∼5.1 ± 0.7 M⊙, ∼ (4.8 ± 0.6) × 1051 erg, ∼0.27−0.30 M⊙, and ∼66.0 ± 9.4 d, respectively. These physical parameters of SN 2012au are close to those inferred for SN 2009jf (a bright SN Ib: Sahu et al. 2011) and – on average – larger than for classical SNe Ib\/c but smaller than for some SNe Ic-BL. SN 2012au manifests larger Mej and MNi in comparison with most of the SNe IIb, Ib, and Ic, which may be the prime reason behind the luminous peak of SN 2012au, as seen in the case of SLSNe I (Nicholl et al. 2015). On the other hand, light-curve decline rates of SN 2012au (at phases ≥+40 d) in all the optical bands are shallower than typically observed in the case of SNe Ib and slow-decaying SLSNe I, and theoretically predicated for 56Co $\\rightarrow \\, ^{56}$fe decay. As SN 2012au exhibits comparatively larger Mej, a larger optical depth resulting in a larger diffusion time-scale (for the trapped energy to cross the outer envelope) could broaden the light curve. Therefore, high trapping of gamma-rays at late phases or higher opacity of massive ejecta are among the plausible interpretations for the modest luminosity decline rate of SN 2012au in comparison with other SNe Ib (Clocchiatti & Wheeler 1997). However, smoothly distributed circumstellar media up to a larger radius could be another possibility behind the late-time shallower decay rate for SN 2012au, but an absence of the CSMI in the late-time spectra ruled out this scenario (Milisavljevic et al. 2018). The late-time bolometric light curve of SN 2012au is better constrained by $L~\\varpropto\\, t^{-2}$, a conventional magnetic dipole equation. Hence for SN 2012au the shallower decay of the late-time light curve might be a potential indicator of a central engine powering source that is accelerating the inner ejecta.","Citation Text":["Clocchiatti & Wheeler 1997"],"Citation Start End":[[2179,2205]]} {"Identifier":"2022MNRAS.512.1499RShibata_et_al._2011_Instance_1","Paragraph":"Let ui be the evolved quantity at the coordinate position xi. Then, THC_M1 approximates the derivative of the flux f(u) at the location xi as\n(31)$$\\begin{eqnarray}\r\n\\partial _x f (u) \\simeq \\frac{F_{i - 1 \/ 2} - F_{i + 1 \/ 2}}{\\Delta x},\r\n\\end{eqnarray}$$where Fi − 1\/2 and Fi + 1\/2 are numerical fluxes defined at $x_i \\mp \\frac{\\Delta x}{2}$, respectively. The fluxes are constructed as linear combination of a non-diffusive second order flux $F^{\\operatorname{HO}}$ and a diffusive first order correction $F^{\\operatorname{LO}}$:\n(32)$$\\begin{eqnarray}\r\nF_{i + 1 \/ 2} = F_{i + 1 \/ 2}^{\\operatorname{HO}} - A_{i + 1 \/ 2} \\varphi _{i + 1 \/ 2} \\left(F_{i + 1 \/ 2}^{\\operatorname{HO}} - F_{i + 1 \/ 2}^{\\operatorname{LO}}\\right) .\r\n\\end{eqnarray}$$The term φi + 1\/2 is the so-called flux limiter (LeVeque 1992), while Ai + 1\/2 is a coefficient introduced to switch off the diffusive correction at high optical depth (more below). The role of the flux limiter is to introduce numerical dissipation in the presence of unresolved features in the solution u and ensure the non-linear stability of the scheme. In particular, if Ai + 1\/2φi + 1\/2 = 0 the second-order flux is used, while if Ai + 1\/2φi + 1\/2 = 1, then the low order flux is used. A standard second order non-diffusive flux is used for $F^{\\operatorname{HO}}$, while the Lax–Friedrichs flux is used for $F^{\\operatorname{LO}}$:\n(33)$$\\begin{eqnarray}\r\nF^{\\operatorname{HO}}_{i + 1 \/ 2} = \\frac{f (u_i) + f (u_{i + 1})}{2},\r\n\\end{eqnarray}$$(34)$$\\begin{eqnarray}\r\nF^{\\operatorname{LO}}_{i + 1 \/ 2} = \\frac{1}{2} [f (u_i) + f (u_{i + 1})] - \\frac{c_{i + 1 \/ 2}}{2} [u_{i + 1} - u_i] .\r\n\\end{eqnarray}$$The characteristic speed in the Lax–Friedrichs flux ci is taken to be the maximum value of the speed of light between the right and left cells\n(35)$$\\begin{eqnarray}\r\nc_{i + 1 \/ 2} = \\max _{a \\in \\lbrace i, i + 1 \\rbrace } \\left\\lbrace \\left| \\alpha _a \\sqrt{\\gamma _a^{x x}} \\pm \\beta _a^x \\right| \\right\\rbrace .\r\n\\end{eqnarray}$$We remark that it is known that the M1 system can, in some circumstances, lead to acausal (faster than light) propagation of neutrinos in GR (Shibata et al. 2011). For this reason, one might argue that a better choice of the characteristic velocity for the Lax–Friedrichs formula would have been given by the eigenvalue of the Jacobian of $\\boldsymbol{F}$. These values are known analytically (Shibata et al. 2011), however in our preliminary tests we found that the use of the full eigenvalues resulted did not improve on the stability or accuracy of the M1 solver.","Citation Text":["Shibata et al. 2011"],"Citation Start End":[[2132,2151]]} {"Identifier":"2022MNRAS.512.1499RShibata_et_al._2011_Instance_2","Paragraph":"Let ui be the evolved quantity at the coordinate position xi. Then, THC_M1 approximates the derivative of the flux f(u) at the location xi as\n(31)$$\\begin{eqnarray}\r\n\\partial _x f (u) \\simeq \\frac{F_{i - 1 \/ 2} - F_{i + 1 \/ 2}}{\\Delta x},\r\n\\end{eqnarray}$$where Fi − 1\/2 and Fi + 1\/2 are numerical fluxes defined at $x_i \\mp \\frac{\\Delta x}{2}$, respectively. The fluxes are constructed as linear combination of a non-diffusive second order flux $F^{\\operatorname{HO}}$ and a diffusive first order correction $F^{\\operatorname{LO}}$:\n(32)$$\\begin{eqnarray}\r\nF_{i + 1 \/ 2} = F_{i + 1 \/ 2}^{\\operatorname{HO}} - A_{i + 1 \/ 2} \\varphi _{i + 1 \/ 2} \\left(F_{i + 1 \/ 2}^{\\operatorname{HO}} - F_{i + 1 \/ 2}^{\\operatorname{LO}}\\right) .\r\n\\end{eqnarray}$$The term φi + 1\/2 is the so-called flux limiter (LeVeque 1992), while Ai + 1\/2 is a coefficient introduced to switch off the diffusive correction at high optical depth (more below). The role of the flux limiter is to introduce numerical dissipation in the presence of unresolved features in the solution u and ensure the non-linear stability of the scheme. In particular, if Ai + 1\/2φi + 1\/2 = 0 the second-order flux is used, while if Ai + 1\/2φi + 1\/2 = 1, then the low order flux is used. A standard second order non-diffusive flux is used for $F^{\\operatorname{HO}}$, while the Lax–Friedrichs flux is used for $F^{\\operatorname{LO}}$:\n(33)$$\\begin{eqnarray}\r\nF^{\\operatorname{HO}}_{i + 1 \/ 2} = \\frac{f (u_i) + f (u_{i + 1})}{2},\r\n\\end{eqnarray}$$(34)$$\\begin{eqnarray}\r\nF^{\\operatorname{LO}}_{i + 1 \/ 2} = \\frac{1}{2} [f (u_i) + f (u_{i + 1})] - \\frac{c_{i + 1 \/ 2}}{2} [u_{i + 1} - u_i] .\r\n\\end{eqnarray}$$The characteristic speed in the Lax–Friedrichs flux ci is taken to be the maximum value of the speed of light between the right and left cells\n(35)$$\\begin{eqnarray}\r\nc_{i + 1 \/ 2} = \\max _{a \\in \\lbrace i, i + 1 \\rbrace } \\left\\lbrace \\left| \\alpha _a \\sqrt{\\gamma _a^{x x}} \\pm \\beta _a^x \\right| \\right\\rbrace .\r\n\\end{eqnarray}$$We remark that it is known that the M1 system can, in some circumstances, lead to acausal (faster than light) propagation of neutrinos in GR (Shibata et al. 2011). For this reason, one might argue that a better choice of the characteristic velocity for the Lax–Friedrichs formula would have been given by the eigenvalue of the Jacobian of $\\boldsymbol{F}$. These values are known analytically (Shibata et al. 2011), however in our preliminary tests we found that the use of the full eigenvalues resulted did not improve on the stability or accuracy of the M1 solver.","Citation Text":["Shibata et al. 2011"],"Citation Start End":[[2384,2403]]} {"Identifier":"2018MNRAS.480.1796SWright_et_al._2010_Instance_1","Paragraph":"To distinguish the emission from AGNs and star formation we use the fact that star-forming galaxies (SFGs) are known to exhibit radio–IR correlation across a wide range of luminosities and redshifts (see Condon 1992; Appleton et al. 2004; Basu et al. 2015). The correlation between 1.4 GHz luminosity and IR luminosity (monochromatic IR luminosity as well as bolometric IR luminosity between 8.0 and 1000 $\\mu$m) in SFGs is attributed to the fact that both radio and IR emission are closely related to star formation (Ivison et al. 2010). AGNs with predominant radio emission from jet deviate from radio–IR correlation by showing radio-excess (Morić et al. 2010; Del Moro et al. 2013). Therefore, we examine if our NLS1s show radio-excess in the radio–IR correlation. We note that radio–IR correlation can be represented as the ratio of IR flux to 1.4 GHz radio flux density i.e. q=log(SIR\/$S_{\\rm 1.4 \\, GHz}$) (see Appleton et al. 2004). For our radio-detected NLS1s we estimate q$_{\\rm 22\\, {\\mu }m}$=log($S_{\\rm 22 {\\mu }m}$\/$S_{\\rm 1.4 \\, GHz}$), where IR flux at 22 $\\mu$m is taken from Wide-field Infrared Survey Explorer (WISE),2 and 1.4 GHz flux density is taken from FIRST whenever available, otherwise from NVSS. WISE is an all sky survey carried out at four MIR photometric bands namely W1 [3.6 $\\mu$m], W2 [4.6 $\\mu$m], W3 [12 $\\mu$m], and W4 [22 $\\mu$m], with 5σ sensitivity of 0.08, 0.11, 1.0, and 6.0 mJy, and angular resolution of 6.1, 6.4, 6.5, and 12.0, respectively (Wright et al. 2010). Using the most recent version of WISE source catalogue (AllWISE3 data release) we obtain MIR counterparts for 481, 480, 440, and 354 of our 498 radio-detected NLS1s with SNR ≥ 5.0 in W1, W2, W3, and W4 bands, respectively. The WISE counterparts of our radio-detected NLS1s are searched within a circle of 2.0 arcsec radius centred at SDSS optical positions. q$_{\\rm 22 {\\mu }m}$ is estimated using k-corrected fluxes, where IR spectral index is derived using W3 and W4 band fluxes, and radio spectral index is derived using 1.4 GHz and 150 MHz flux densities, whenever available, otherwise an average radio spectral index of −0.7 is considered.","Citation Text":["Wright et al. 2010"],"Citation Start End":[[1487,1505]]} {"Identifier":"2022AandA...664A.12Noyes_et_al._1984_Instance_1","Paragraph":"Efforts have been made to model the signals caused by different sources of stellar variability within the RV time series (e.g., Tuomi et al. 2013; Rajpaul et al. 2015; Davis et al. 2017; Simola et al. 2019). Several solutions have been successfully proposed in order to deal with stellar oscillations and granulation phenomena, such as: calculating stellar evolution sequences (e.g., Christensen-Dalsgaard et al. 1995); fitting a two-level structure tracking (TST) algorithm based on a two-level representation of granulation (Del Moro 2004); using daytime spectra of the Sun in order to measure the solar oscillations (e.g., Kjeldsen et al. 2008; Lefebvre et al. 2008); and characterizing the statistical properties of magnetic activity cycles focusing on HARPS observations (e.g., Pepe et al. 2011; Dumusque et al. 2011b). However, properly modeling the other sources of stellar activity remains extremely challenging (e.g., Nava et al. 2019). In the present work, we deal with the cross correlation function (CCF) that is derived from the stellar spectrum (e.g., Hatzes 1996; Hatzes & Cochran 2000; Fiorenzano et al. 2005). As it is well known, the CCF barycenter estimates the RV of the star. The asymmetry and the full width at half maximum (FWHM) of the CCF give a strong indication for stellar activity, meaning that variations in RV are caused by active regions rather than by an exoplanet (e.g., Hatzes 1996; Queloz et al. 2001; Boisse et al. 2011; Figueira et al. 2013; Simola et al. 2019). Several solutions have been successfully proposed for mitigating stellar activity perturbations when working with RV measurements, including: decorrelating RV data against activity indicators such as log ${{R'}_{{\\rm{HK}}}}$R′HK (e.g., Wilson 1968; Noyes et al. 1984) or Hα (e.g., Robertson et al. 2014); modeling stellar activity by fitting Gaussian processes (GPs, Rasmussen & Williams 2005; Haywood et al. 2014; Rajpaul et al. 2015); or moving averages (e.g., Tuomi et al. 2013) to the RV data. A common statistic employed for identifying changes in the shape of the CCF is the bisector span (e.g., Hatzes 1996; Queloz et al. 2001).","Citation Text":["Noyes et al. 1984"],"Citation Start End":[[1750,1767]]} {"Identifier":"2019MNRAS.486.1608NBinney_2004_Instance_1","Paragraph":"The clearest examples of host–AGN interaction are arguably found in nearby brightest cluster galaxies. The AGN in these systems have been shown to deposit vast amounts of energy into the surrounding intracluster medium via heating and (mega-parsec scale) jets both observationally and by means of modelling (e.g. Binney 2004; Scannapieco, Silk & Bouwens 2005; Gitti, Brighenti & McNamara 2012, for a review; English, Hardcastle & Krause 2016), which maintain the hot-gas reservoirs in these systems, prevent cooling flows, and thus suppress star formation (e.g. Binney & Tabor 1995; Li et al. 2015). In lower density environments (where the majority of galaxies live), the empirical picture is much less clear. Direct observational evidence for AGN feedback on galactic scales in such environments remains sparse. More specifically, while outflows have been observationally detected in a number of instances around AGN in various gas phases, most of these detections have been made in ultra-luminous infrared galaxies or some of the closest quasar–host galaxies (e.g. Rupke, Veilleux & Sanders 2005b; Nyland et al. 2013; Harrison et al. 2014), with only a few examples where the AGN have been shown to couple with kpc-scale outflows that are capable of impacting star-formation on galactic scales (for a review Cicone et al. 2014; Harrison 2017). Thus, it is still unclear to what extent the general AGN population could drive kpc-scale galactic outflows capable of possibly limiting or quenching star-formation in the local Universe. Indeed, recent observational work has cast doubt on the ability of AGN to directly regulate star formation in the nearby Universe. For example, Schawinski et al. (2014) found that black hole accretion occurs preferentially in quenched galaxies that experienced a rapid decay of their star-formation rates. Based on stellar population analysis, such a time delay between the peak of star formation and the onset of AGN activity has been reported to be of at least several dynamical time-scales (e.g. Kaviraj et al. 2015; Shabala et al. 2017, for radio and e.g. Schawinski et al. 2007; Kaviraj 2009; Wild, Heckman & Charlot 2010 for optical). AGN may therefore not play a significant direct role in regulating their associated star formation episodes as they would not couple directly to the cold-gas reservoir (see, e.g. the models of Kaviraj et al. 2011). Using observations for cold-gas outflows, this has been directly confirmed for radio AGN, which are found to couple mainly to residual gas in galaxies where the gas reservoir is already significantly depleted (e.g. Sarzi et al. 2016). A fuller understanding of the role of AGN in regulating star formation demands a direct study of whether outflows of neutral material (which are ultimately responsible for quenching star formation) are more likely launched in AGN hosts. Most importantly, a quantitative statement about the putative role of AGN in influencing the evolution of their host galaxy requires a study that employs a complete sample of such AGN in the local Universe. Performing such an analysis is the purpose of this paper.","Citation Text":["Binney 2004"],"Citation Start End":[[313,324]]} {"Identifier":"2019MNRAS.486.1608NSarzi_et_al._2016_Instance_1","Paragraph":"The clearest examples of host–AGN interaction are arguably found in nearby brightest cluster galaxies. The AGN in these systems have been shown to deposit vast amounts of energy into the surrounding intracluster medium via heating and (mega-parsec scale) jets both observationally and by means of modelling (e.g. Binney 2004; Scannapieco, Silk & Bouwens 2005; Gitti, Brighenti & McNamara 2012, for a review; English, Hardcastle & Krause 2016), which maintain the hot-gas reservoirs in these systems, prevent cooling flows, and thus suppress star formation (e.g. Binney & Tabor 1995; Li et al. 2015). In lower density environments (where the majority of galaxies live), the empirical picture is much less clear. Direct observational evidence for AGN feedback on galactic scales in such environments remains sparse. More specifically, while outflows have been observationally detected in a number of instances around AGN in various gas phases, most of these detections have been made in ultra-luminous infrared galaxies or some of the closest quasar–host galaxies (e.g. Rupke, Veilleux & Sanders 2005b; Nyland et al. 2013; Harrison et al. 2014), with only a few examples where the AGN have been shown to couple with kpc-scale outflows that are capable of impacting star-formation on galactic scales (for a review Cicone et al. 2014; Harrison 2017). Thus, it is still unclear to what extent the general AGN population could drive kpc-scale galactic outflows capable of possibly limiting or quenching star-formation in the local Universe. Indeed, recent observational work has cast doubt on the ability of AGN to directly regulate star formation in the nearby Universe. For example, Schawinski et al. (2014) found that black hole accretion occurs preferentially in quenched galaxies that experienced a rapid decay of their star-formation rates. Based on stellar population analysis, such a time delay between the peak of star formation and the onset of AGN activity has been reported to be of at least several dynamical time-scales (e.g. Kaviraj et al. 2015; Shabala et al. 2017, for radio and e.g. Schawinski et al. 2007; Kaviraj 2009; Wild, Heckman & Charlot 2010 for optical). AGN may therefore not play a significant direct role in regulating their associated star formation episodes as they would not couple directly to the cold-gas reservoir (see, e.g. the models of Kaviraj et al. 2011). Using observations for cold-gas outflows, this has been directly confirmed for radio AGN, which are found to couple mainly to residual gas in galaxies where the gas reservoir is already significantly depleted (e.g. Sarzi et al. 2016). A fuller understanding of the role of AGN in regulating star formation demands a direct study of whether outflows of neutral material (which are ultimately responsible for quenching star formation) are more likely launched in AGN hosts. Most importantly, a quantitative statement about the putative role of AGN in influencing the evolution of their host galaxy requires a study that employs a complete sample of such AGN in the local Universe. Performing such an analysis is the purpose of this paper.","Citation Text":["Sarzi et al. 2016"],"Citation Start End":[[2606,2623]]} {"Identifier":"2021MNRAS.506.2181LGerhard_et_al._2001_Instance_1","Paragraph":"There are still several sources of systematics we do not consider in this paper. For instance, whether the use of a different mass distribution models for these lenses could significantly affect the final result. Therefore, we performed a sensitivity analysis and repeated the above calculation using the extend power law (EPL) lens model, in which the luminosity density profile [v(r) ∼ r−δ] is different from the total mass (luminous plus dark matter) density profile ρ(r) ∼ r−α. Such lens model has found widespread astrophysical applications in the literature (Cao et al. 2016a; Xia et al. 2017; Qi et al. 2019), considering the anisotropic distribution of stellar velocity dispersion β (Koopmans 2005; Cao et al. 2017b; Chen et al. 2019). With the EPL lens parameters (α, β, δ) modelled by Gaussian distributions α = 2.00 ± 0.08, δ = 2.40 ± 0.11, and β = 0.18 ± 0.13 (Gerhard et al. 2001; Bolton, Rappaport & Burles 2006; Graur et al. 2014; Schwab, Bolton & Rappaport 2010), the scatter plot of the deviation Tzs in EPL model is shown in Fig. 4. Our results provide the deviation Tzs = 0.974 ± 0.017 [corresponding to c(zs) = 2.922(± 0.051) × 105 km s−1], and the median value Med(Tzs) = 0.983 with the median absolute deviation MAD(Tzs) = 0.259 for the full lens sample. Therefore, our results show that the assumed lens model has a slight impact on the SOL constraint, which highlights the importance of auxiliary data (such as more high quality integral field unit) in improving constraints on the density profile of gravitational lenses. More detailed models of mass distribution, such as Navarro–Frenk–White density profile (suitable for dark matter distribution; Navarro, Frenk & White 1997), Sersic-like profile (suitable for stellar light distribution) (Sérsic 1968), pseudo-isothermal elliptical mass distribution, could also be considered in this context (Kassiola & Kovner 1993). However, strong lensing observables we used are determined by the total mass inside the Einstein radius. Hence, they are not so sensitive to the details of the very central distribution like cusps (besides the extremal cases). Moreover, the Einstein rings of the lenses we used corresponded to less than 10 kpc hence the NFW profile of the dark halo would not likely be manifested.","Citation Text":["Gerhard et al. 2001"],"Citation Start End":[[873,892]]} {"Identifier":"2021AandA...655A..7Sanna_et_al._2016_Instance_1","Paragraph":"In this paper, we report on spectroscopic CH3CN, CH3OH (methanol), and dust continuum observations with the Atacama Large Millimeter\/submillimeter Array (ALMA) at 349 GHz with an angular resolution of 0′′.1. We exploit the CH3CN (19K–18K) K-ladder, with excitation energies ranging from 168 K (for K = 0) to 881 K (for K = 10), to probe, at different radii, the physical conditions in the accretion disk of an early-type young star. We targeted the star-forming region G023.01−00.41, at a trigonometric distance of 4.59\n\n$^{+0.38}_{-0.33}$\n\n\n\n\n\n−0.33\n\n+0.38\n\n\n\n kpc from the Sun (Brunthaler et al. 2009), where we recently revealed the accretion disk around a young star of 104.6 L⊙, corresponding to a ZAMS star of 20 M⊙ (Sanna et al. 2019, their Fig. 1); the disk was imaged by means of spectroscopic ALMA observations of both CH3CN and CH3OH lines at 0′′.2 resolution inthe 230 GHz band. The disk extends up to radii of 3000 au from the central star where it warps above the midplane; here, we resolve the outer disk regions in two apparent spirals projected onto the plane of the sky. We showed that molecular gas is falling in and slowly rotating with sub-Keplerian velocities down to radii of 500 au from the central star, where we measured a mass infall rate of 6 × 10−4 M⊙ yr−1 (Sanna et al. 2019, their Fig. 5). The disk and star system drives a radio continuum jet and a molecular outflow aligned along a position angle of 57°, measured east of north (Sanna et al. 2016, their Fig. 2); their projected axis is oriented perpendicular to the disk midplane whose inclination with respect to the line-of-sight was estimated to be less than 30° (namely, the disk is seen approximately edge-on; Sanna et al. 2014, 2019). Previously, we also measured the average gas conditions over the same extent of the whole disk, by means of Submillimeter Array (SMA) observations of the CH3CN (12K–11K) emission, and we estimated a kinetic temperature of 195 K and CH3CN column density of 5.1 × 1016 cm−2 (Sanna et al. 2014, their Fig. 2 and Table 4).","Citation Text":["Sanna et al. 2016"],"Citation Start End":[[1462,1479]]} {"Identifier":"2021AandA...655A..7Sanna_et_al._2014_Instance_1","Paragraph":"In this paper, we report on spectroscopic CH3CN, CH3OH (methanol), and dust continuum observations with the Atacama Large Millimeter\/submillimeter Array (ALMA) at 349 GHz with an angular resolution of 0′′.1. We exploit the CH3CN (19K–18K) K-ladder, with excitation energies ranging from 168 K (for K = 0) to 881 K (for K = 10), to probe, at different radii, the physical conditions in the accretion disk of an early-type young star. We targeted the star-forming region G023.01−00.41, at a trigonometric distance of 4.59\n\n$^{+0.38}_{-0.33}$\n\n\n\n\n\n−0.33\n\n+0.38\n\n\n\n kpc from the Sun (Brunthaler et al. 2009), where we recently revealed the accretion disk around a young star of 104.6 L⊙, corresponding to a ZAMS star of 20 M⊙ (Sanna et al. 2019, their Fig. 1); the disk was imaged by means of spectroscopic ALMA observations of both CH3CN and CH3OH lines at 0′′.2 resolution inthe 230 GHz band. The disk extends up to radii of 3000 au from the central star where it warps above the midplane; here, we resolve the outer disk regions in two apparent spirals projected onto the plane of the sky. We showed that molecular gas is falling in and slowly rotating with sub-Keplerian velocities down to radii of 500 au from the central star, where we measured a mass infall rate of 6 × 10−4 M⊙ yr−1 (Sanna et al. 2019, their Fig. 5). The disk and star system drives a radio continuum jet and a molecular outflow aligned along a position angle of 57°, measured east of north (Sanna et al. 2016, their Fig. 2); their projected axis is oriented perpendicular to the disk midplane whose inclination with respect to the line-of-sight was estimated to be less than 30° (namely, the disk is seen approximately edge-on; Sanna et al. 2014, 2019). Previously, we also measured the average gas conditions over the same extent of the whole disk, by means of Submillimeter Array (SMA) observations of the CH3CN (12K–11K) emission, and we estimated a kinetic temperature of 195 K and CH3CN column density of 5.1 × 1016 cm−2 (Sanna et al. 2014, their Fig. 2 and Table 4).","Citation Text":["Sanna et al. 2014"],"Citation Start End":[[1998,2015]]} {"Identifier":"2015AandA...577A..4Bárta_&_Karlický_2000_Instance_1","Paragraph":"The initialization of solar flares remains an unsolved problem. Early ideas on how the initialization might occur were described by Norman & Smith (1978). They argued that flare process cannot start in the entire flare volume at one instant, and proposed that the flare onset was localized in a small part of an active region, from which the energy release extends as dissipation spreading process throughout the flare volume. Two types of agents that may lead to this kind of a dissipation process were addressed: electron beams and shock waves. These agents can trigger flares at large distances from their initial locations, causing sympathetic (simultaneous) flares or leading to a sequential flare energy release in one active region (Liu et al. 2009; Zuccarello et al. 2009). These triggering processes were numerically studied by Karlický & Jungwirth (1989) and Odstrčil & Karlický (1997). Karlický & Jungwirth (1989) assumed that electron beams, penetrating into the current sheet in the magnetic reconnection region, generate Langmuir waves. Then, using the particle-in-cell model, the authors studied the effects of these electrostatic waves on the plasma system. Sufficiently strong Langmuir waves were found to be able to generate ion-sound waves through the three-wave decay process (Bárta & Karlický 2000). These ion-sound waves increase electrical resistivity in the current sheet system, which results in the onset of the energy dissipation. Thus, the electron beams are able to cause magnetic reconnection. Odstrčil & Karlický (1997) studied the mechanism for the flare trigger by shock waves. They used a 2D magnetohydrodynamic model with the MHD shock wave propagating towards the current sheet. A portion of the shock wave passed through the sheet, and the rest was reflected. Nothing occurred at the very beginning of the wave-current sheet interaction. However, after some time, specific plasma flows around the current sheet were formed, which led to the start of magnetic reconnection. This shows that for reconnection to be triggered, the enhanced electrical resistivity as well as the plasma flows are important. ","Citation Text":["Bárta & Karlický 2000"],"Citation Start End":[[1297,1318]]} {"Identifier":"2018ApJ...854...33Z__Ballantyne_et_al._2006_Instance_1","Paragraph":"Given their very large column densities, the most obscured sources can effectively be detected in the X-rays at rest-frame energies \n\n\n\n\n\n because their primary continuum is strongly suppressed at softer energies. This can be currently done: (i) locally (\n\n\n\n\n\n) by targeting bright sources (e.g., \n\n\n\n\n\n; Baumgartner et al. 2013) Seyfert-type (\n\n\n\n\n\n ) with hard X-ray (\n\n\n\n\n\n keV) surveys, such as those performed by Swift\/BAT and INTEGRAL (Krivonos et al. 2007; Ajello et al. 2008); and (ii) at high redshifts (\n\n\n\n\n\n) with the most sensitive Chandra\/XMM-Newton observations of the deep\/medium survey fields (e.g., Civano et al. 2016; Luo et al. 2017). Through either spectral or hardness ratio analysis, they allow one to quantify and characterize the obscured Compton-thin (\n\n\n\n\n\n) AGN population and further shed light on the known decreasing trend between the numerical relevance of this population compared to all AGN (absorbed fraction) and the source luminosity (Lawrence & Elvis 1982; Gilli et al. 2007; Burlon et al. 2011; Buchner et al. 2015) and its redshift evolution (La Franca et al. 2005; Ballantyne et al. 2006; Treister & Urry 2006; Aird et al. 2015a; Buchner et al. 2015; Liu et al. 2017). They also allow exploration of the importance of the CT population, although with different constraining power and different non-negligible degrees of bias—especially at the highest column densities and lowest luminosities (e.g., Burlon et al. 2011; Brightman et al. 2014; Buchner et al. 2015; Lanzuisi et al. 2015; Ricci et al. 2015). Indeed, the large diversity in the spectral shapes, as well as poorly explored observational parameters in low counting regimes26\n\n26\nI.e., at the highest column densities or at the high\/low-energy spectral boundaries where the instruments are less sensitive.\n such as the high energy cut-off and the reflection strength at high energies (Treister et al. 2009; Ballantyne et al. 2011, hereafter BA11), the scattered fractions at low energies (Brightman & Ueda 2012; Lanzuisi et al. 2015), or physical parameters such as the Eddington ratio (Draper & Ballantyne 2010), may further introduce uncertainty or biases, enlarging the possible range of the fraction of CT sources to an order of magnitude (Akylas et al. 2012) or even significantly reducing their importance (Gandhi et al. 2007). Indeed, given the paucity of CT sources effectively contributing to the CXB missing flux, the most recent population-synthesis models have tried to explain the CXB missing component as mainly a pronounced reflection contribution from less obscured sources with a reduced contribution by CT AGN (Treister et al. 2009; Ballantyne et al. 2011; Akylas et al. 2012).","Citation Text":["Ballantyne et al. 2006"],"Citation Start End":[[1107,1129]]} {"Identifier":"2015AandA...575A.111D__Mack_et_al._(2014)_Instance_1","Paragraph":"At present, few very wide binaries are known where a planetary system was discovered around one of the stellar components. The star HD 20782 is the binary companion of HD 20781, with a projected separation of ~9000 AU, and it hosts a Jupiter-mass planet on a very eccentric orbit at ~1.4 AU (Jones et al. 2006)2. The very high eccentricity reported in the literature (e = 0.97) could be the result of significant perturbations experienced by the planet during the evolution of the system and might be due to the stellar companion. In this binary system, where both the components can be well analysed separately, a comparative study of the physical properties of the pair could help explain the nature of the planetary system. To investigate any existing link between the planet formation mechanisms and the chemical composition of the host stars, Mack et al. (2014) performed a detailed elemental abundance analysis of the atmospheres of HD 20781\/82, by considering that both stars host planets. This kind of study, when at least one component hosts a close-in giant planet, could result in the evidence of chemical imprints left in the parent star suggesting the ingestion of material from the circumstellar disk (and possibly also from planets) driven by the dynamical evolution of the planet orbit. When a star with a close-in giant planet is found to be enriched with elements of high condensation temperature, as suggested by Schuler et al. (2011b), this can be related to the inward migration of the planet from the outer regions of the circumstellar disk, where it formed, to the present position closer to the star (Ida & Lin 2008; Raymond et al. 2011). Mack et al. (2014) found quite significant positive trends for both stars with the condensation temperature among the elemental abundances, and suggested that the host stars accreted rocky bodies with mass between 10 and 20 M⊕ initially formed inside the location of the detected planets. Searches for abundance anomalies possibly caused by the ingestion of planetary material by the central star were also conducted by (Desidera et al. 2004, 2007; and references therein) for a sample of wide binaries. These authors found that the amount of iron accreted by the companion that is nominally richer in metal (in binaries with components having Teff> 5500 K) is comparable to the estimates of the rocky material accreted by the Sun during its main-sequence lifetime, and therefore concluded that the metal enrichment due to the ingestion of material of planetary origin is not a common event. ","Citation Text":["Mack et al. (2014)"],"Citation Start End":[[848,866]]} {"Identifier":"2015AandA...575A.111D__Mack_et_al._(2014)_Instance_2","Paragraph":"At present, few very wide binaries are known where a planetary system was discovered around one of the stellar components. The star HD 20782 is the binary companion of HD 20781, with a projected separation of ~9000 AU, and it hosts a Jupiter-mass planet on a very eccentric orbit at ~1.4 AU (Jones et al. 2006)2. The very high eccentricity reported in the literature (e = 0.97) could be the result of significant perturbations experienced by the planet during the evolution of the system and might be due to the stellar companion. In this binary system, where both the components can be well analysed separately, a comparative study of the physical properties of the pair could help explain the nature of the planetary system. To investigate any existing link between the planet formation mechanisms and the chemical composition of the host stars, Mack et al. (2014) performed a detailed elemental abundance analysis of the atmospheres of HD 20781\/82, by considering that both stars host planets. This kind of study, when at least one component hosts a close-in giant planet, could result in the evidence of chemical imprints left in the parent star suggesting the ingestion of material from the circumstellar disk (and possibly also from planets) driven by the dynamical evolution of the planet orbit. When a star with a close-in giant planet is found to be enriched with elements of high condensation temperature, as suggested by Schuler et al. (2011b), this can be related to the inward migration of the planet from the outer regions of the circumstellar disk, where it formed, to the present position closer to the star (Ida & Lin 2008; Raymond et al. 2011). Mack et al. (2014) found quite significant positive trends for both stars with the condensation temperature among the elemental abundances, and suggested that the host stars accreted rocky bodies with mass between 10 and 20 M⊕ initially formed inside the location of the detected planets. Searches for abundance anomalies possibly caused by the ingestion of planetary material by the central star were also conducted by (Desidera et al. 2004, 2007; and references therein) for a sample of wide binaries. These authors found that the amount of iron accreted by the companion that is nominally richer in metal (in binaries with components having Teff> 5500 K) is comparable to the estimates of the rocky material accreted by the Sun during its main-sequence lifetime, and therefore concluded that the metal enrichment due to the ingestion of material of planetary origin is not a common event. ","Citation Text":["Mack et al. (2014)"],"Citation Start End":[[1663,1681]]} {"Identifier":"2015AandA...575A.11Jones_et_al._2006_Instance_1","Paragraph":"At present, few very wide binaries are known where a planetary system was discovered around one of the stellar components. The star HD 20782 is the binary companion of HD 20781, with a projected separation of ~9000 AU, and it hosts a Jupiter-mass planet on a very eccentric orbit at ~1.4 AU (Jones et al. 2006)2. The very high eccentricity reported in the literature (e = 0.97) could be the result of significant perturbations experienced by the planet during the evolution of the system and might be due to the stellar companion. In this binary system, where both the components can be well analysed separately, a comparative study of the physical properties of the pair could help explain the nature of the planetary system. To investigate any existing link between the planet formation mechanisms and the chemical composition of the host stars, Mack et al. (2014) performed a detailed elemental abundance analysis of the atmospheres of HD 20781\/82, by considering that both stars host planets. This kind of study, when at least one component hosts a close-in giant planet, could result in the evidence of chemical imprints left in the parent star suggesting the ingestion of material from the circumstellar disk (and possibly also from planets) driven by the dynamical evolution of the planet orbit. When a star with a close-in giant planet is found to be enriched with elements of high condensation temperature, as suggested by Schuler et al. (2011b), this can be related to the inward migration of the planet from the outer regions of the circumstellar disk, where it formed, to the present position closer to the star (Ida & Lin 2008; Raymond et al. 2011). Mack et al. (2014) found quite significant positive trends for both stars with the condensation temperature among the elemental abundances, and suggested that the host stars accreted rocky bodies with mass between 10 and 20 M⊕ initially formed inside the location of the detected planets. Searches for abundance anomalies possibly caused by the ingestion of planetary material by the central star were also conducted by (Desidera et al. 2004, 2007; and references therein) for a sample of wide binaries. These authors found that the amount of iron accreted by the companion that is nominally richer in metal (in binaries with components having Teff> 5500 K) is comparable to the estimates of the rocky material accreted by the Sun during its main-sequence lifetime, and therefore concluded that the metal enrichment due to the ingestion of material of planetary origin is not a common event. ","Citation Text":["Jones et al. 2006"],"Citation Start End":[[292,309]]} {"Identifier":"2021AandA...654A.152B__Lai_2014_Instance_1","Paragraph":"Measurements of star-planet alignments are essential to improving our understanding of exoplanet formation and evolution, especially for planets that migrated close to their star. Disk-driven migration is expected to conserve the initial alignment between the angular momentums of the protoplanetary disk and of the planetary orbits (e.g., Winn & Fabrycky 2015). A variety of formation and migration pathways can, however, lead to misalignments between the spins of a star and of its planets’ orbits, namely: a primordial tilt of the star or the protoplanetary disk (e.g., Lai et al. 2011; Bate et al. 2010; Fielding et al. 2015); a tidal torque on the protoplanetary disk from a neighboring star (e.g., Lai 2014; Batygin 2012; Zanazzi & Lai 2018); a tidal torque on the inner planetary system from an outer companion (e.g., Huber et al. 2013); and scattering or secular interactions between the inner planets and an outer planetary or stellar companion (e.g., Wu & Murray 2003; Chatterjee et al. 2008; Fabrycky & Tremaine 2007; Teyssandier et al. 2013). In this context, determining the orbital architecture of multi-planet systems is of great relevance as the mutual inclinations between theplanets, and with the star, can help distinguish among various formation and migration scenarios. Early measurements revealed coplanar orbits that are well aligned with the stellar equator in multi-planet systems (e.g. Figueira et al. 2012; Hirano et al. 2012; Sanchis-Ojeda et al. 2012; Albrecht et al. 2013; Chaplin et al. 2013; Van Eylen et al. 2014), standing in contrast to the broad distribution of misalignments observed for hot Jupiters (e.g., Naoz et al. 2012; Albrecht et al. 2012; Davies et al. 2014) and suggesting that their orbital planes still trace a primordial alignment with the protoplanetary disk. Interestingly, spin-orbit measurements in young systems (100 Myr) have shown prograde and aligned orbits (Palle et al. 2020; Zhou et al. 2020; Mann et al. 2020). Other studies have unveiled substantial misalignments in multi-planet systems (Huber et al. 2013; Walkowicz & Basri 2013; Hirano et al. 2014; Hjorth et al. 2021; Zhang et al. 2021), hinting at more complex formation processes (e.g., Spalding & Batygin 2014; Spalding & Millholland 2020) or dynamical histories (e.g. Gratia & Fabrycky 2017).","Citation Text":["Lai 2014"],"Citation Start End":[[704,712]]} {"Identifier":"2021AandA...654A.15Figueira_et_al._2012_Instance_1","Paragraph":"Measurements of star-planet alignments are essential to improving our understanding of exoplanet formation and evolution, especially for planets that migrated close to their star. Disk-driven migration is expected to conserve the initial alignment between the angular momentums of the protoplanetary disk and of the planetary orbits (e.g., Winn & Fabrycky 2015). A variety of formation and migration pathways can, however, lead to misalignments between the spins of a star and of its planets’ orbits, namely: a primordial tilt of the star or the protoplanetary disk (e.g., Lai et al. 2011; Bate et al. 2010; Fielding et al. 2015); a tidal torque on the protoplanetary disk from a neighboring star (e.g., Lai 2014; Batygin 2012; Zanazzi & Lai 2018); a tidal torque on the inner planetary system from an outer companion (e.g., Huber et al. 2013); and scattering or secular interactions between the inner planets and an outer planetary or stellar companion (e.g., Wu & Murray 2003; Chatterjee et al. 2008; Fabrycky & Tremaine 2007; Teyssandier et al. 2013). In this context, determining the orbital architecture of multi-planet systems is of great relevance as the mutual inclinations between theplanets, and with the star, can help distinguish among various formation and migration scenarios. Early measurements revealed coplanar orbits that are well aligned with the stellar equator in multi-planet systems (e.g. Figueira et al. 2012; Hirano et al. 2012; Sanchis-Ojeda et al. 2012; Albrecht et al. 2013; Chaplin et al. 2013; Van Eylen et al. 2014), standing in contrast to the broad distribution of misalignments observed for hot Jupiters (e.g., Naoz et al. 2012; Albrecht et al. 2012; Davies et al. 2014) and suggesting that their orbital planes still trace a primordial alignment with the protoplanetary disk. Interestingly, spin-orbit measurements in young systems (100 Myr) have shown prograde and aligned orbits (Palle et al. 2020; Zhou et al. 2020; Mann et al. 2020). Other studies have unveiled substantial misalignments in multi-planet systems (Huber et al. 2013; Walkowicz & Basri 2013; Hirano et al. 2014; Hjorth et al. 2021; Zhang et al. 2021), hinting at more complex formation processes (e.g., Spalding & Batygin 2014; Spalding & Millholland 2020) or dynamical histories (e.g. Gratia & Fabrycky 2017).","Citation Text":["Figueira et al. 2012"],"Citation Start End":[[1412,1432]]} {"Identifier":"2015MNRAS.448.2210E__Warwick_et_al._2012_Instance_1","Paragraph":"Each 7-tile observation with Swift-XRT covers ∼ 0.8 deg2, with typical exposures of 1–2 ks per tile. In such exposure times, our detection limit is 6–10 × 10−13 erg cm−2 s−1(corresponding to 90 per cent completeness; see Evans et al. 2014, fig. 14). This is significantly more sensitive than the RASS, which covers 92 per cent of the sky down to 0.1 ct s−1 in the PSPC6 (Voges et al. 1999), which corresponds to 2.8 × 10−12 erg cm−2 s−1 in the 0.3–10 keV band covered by XRT (assuming the canonical AGN spectrum described above). For absorbed sources (i.e. with little flux in the ROSAT bandpass), the increase in sensitivity of Swift-XRT over ROSAT is even greater. The XSS provides hard-band coverage, being sensitive to ∼ 3 × 10−12 erg cm−2 s−1 in the 2–10 keV band (Warwick et al. 2012), however it only covers ∼ 2\/3 of the sky. Because of the sensitivity of the XRT compared to these catalogues, and the low spatial coverage of deeper catalogues like 1CSC (Evans et al. 2010),7 3XMMi-DR4 (Watson et al., in preparation) and 1SXPS (Evans et al. 2014), we expect to discover uncatalogued X-ray sources that are serendipitously present in the IceCube error region. We therefore need to be able to identify the true X-ray counterpart to the neutrino trigger from among the unrelated objects detected in the field of view. The first step is to remove any sources which are already known X-ray emitters (and are not in outburst at the time of the Swift observations). We searched the X-ray Master catalogue8 for any catalogued X-ray object with a position agreeing with our XRT position at the 3σ level (including any systematic errors on the catalogued positions). For all observations after 2012 October9 we also searched for matches in the 1SXPS catalogue. The sources with catalogue matches are indicated in Table 2, and details of the matches are given in Table 4. In all cases where a match was found, the XRT flux was consistent with (at the 2σ level) or occasionally slightly lower than the catalogued flux, therefore these sources were all rejected as possible counterparts.","Citation Text":["Warwick et al. 2012"],"Citation Start End":[[770,789]]} {"Identifier":"2015MNRAS.448.2210EEvans_et_al._2010_Instance_1","Paragraph":"Each 7-tile observation with Swift-XRT covers ∼ 0.8 deg2, with typical exposures of 1–2 ks per tile. In such exposure times, our detection limit is 6–10 × 10−13 erg cm−2 s−1(corresponding to 90 per cent completeness; see Evans et al. 2014, fig. 14). This is significantly more sensitive than the RASS, which covers 92 per cent of the sky down to 0.1 ct s−1 in the PSPC6 (Voges et al. 1999), which corresponds to 2.8 × 10−12 erg cm−2 s−1 in the 0.3–10 keV band covered by XRT (assuming the canonical AGN spectrum described above). For absorbed sources (i.e. with little flux in the ROSAT bandpass), the increase in sensitivity of Swift-XRT over ROSAT is even greater. The XSS provides hard-band coverage, being sensitive to ∼ 3 × 10−12 erg cm−2 s−1 in the 2–10 keV band (Warwick et al. 2012), however it only covers ∼ 2\/3 of the sky. Because of the sensitivity of the XRT compared to these catalogues, and the low spatial coverage of deeper catalogues like 1CSC (Evans et al. 2010),7 3XMMi-DR4 (Watson et al., in preparation) and 1SXPS (Evans et al. 2014), we expect to discover uncatalogued X-ray sources that are serendipitously present in the IceCube error region. We therefore need to be able to identify the true X-ray counterpart to the neutrino trigger from among the unrelated objects detected in the field of view. The first step is to remove any sources which are already known X-ray emitters (and are not in outburst at the time of the Swift observations). We searched the X-ray Master catalogue8 for any catalogued X-ray object with a position agreeing with our XRT position at the 3σ level (including any systematic errors on the catalogued positions). For all observations after 2012 October9 we also searched for matches in the 1SXPS catalogue. The sources with catalogue matches are indicated in Table 2, and details of the matches are given in Table 4. In all cases where a match was found, the XRT flux was consistent with (at the 2σ level) or occasionally slightly lower than the catalogued flux, therefore these sources were all rejected as possible counterparts.","Citation Text":["Evans et al. 2010"],"Citation Start End":[[962,979]]} {"Identifier":"2022ApJ...937...29F__Johnstone_et_al._2013_Instance_1","Paragraph":"While these large monitoring campaigns are important for establishing the distribution of accretion variability events, their low angular resolution precludes a detailed investigation of how the envelope structure may influence the response to accretion luminosity variations. Modeling of the envelope response predicts that higher-resolution observations may be more sensitive to accretion rate changes, as the change in brightness of the outer envelope is likely to be dominated by heating from the interstellar radiation field (ISRF; Johnstone et al. 2013). The details of the envelope structure, including the likely presence of outflow cavities and dust sublimation fronts, may also impact the observed response (Baek et al. 2020; hereafter, B20). High-resolution monitoring of embedded protostars with millimeter wavelength facilities should thus be able to probe the envelope structure, in addition to identifying variability behavior. In this paper, we thus analyze observations from the Atacama Large Millimeter\/submillimeter Array (ALMA) and the Submillimeter Array (SMA) of variable protostars in Serpens Main, monitored by the JCMT Transient Survey. Particular emphasis is placed on EC 53 (V371 Ser), which exhibits ∼18 month periodic accretion bursts, the most recent of which was observed at high cadence with the SMA and JCMT. We interpret the light curves from our monitoring programs using a simple toy model of the propagation of accretion bursts through the envelope, which we also use to further explore how the properties of the envelope and observational setup affect the burst response. The remainder of this paper is organized as follows. In Section 2, we describe our variable protostar targets and the ALMA, SMA, and JCMT observations, while in Section 3, we provide the details of our data reduction and present light curves of our targets. In Section 4, we develop a toy model to interpret the SMA and JCMT observations of EC 53, and this is followed in Section 5 by a further exploration with the toy model of the observation of generic accretion bursts. We then discuss our results and observational\/modeling caveats in Section 6, and finish with a brief summary of our major conclusions in Section 7.","Citation Text":["Johnstone et al. 2013"],"Citation Start End":[[537,558]]} {"Identifier":"2022ApJ...937...29FBaek_et_al._2020_Instance_1","Paragraph":"While these large monitoring campaigns are important for establishing the distribution of accretion variability events, their low angular resolution precludes a detailed investigation of how the envelope structure may influence the response to accretion luminosity variations. Modeling of the envelope response predicts that higher-resolution observations may be more sensitive to accretion rate changes, as the change in brightness of the outer envelope is likely to be dominated by heating from the interstellar radiation field (ISRF; Johnstone et al. 2013). The details of the envelope structure, including the likely presence of outflow cavities and dust sublimation fronts, may also impact the observed response (Baek et al. 2020; hereafter, B20). High-resolution monitoring of embedded protostars with millimeter wavelength facilities should thus be able to probe the envelope structure, in addition to identifying variability behavior. In this paper, we thus analyze observations from the Atacama Large Millimeter\/submillimeter Array (ALMA) and the Submillimeter Array (SMA) of variable protostars in Serpens Main, monitored by the JCMT Transient Survey. Particular emphasis is placed on EC 53 (V371 Ser), which exhibits ∼18 month periodic accretion bursts, the most recent of which was observed at high cadence with the SMA and JCMT. We interpret the light curves from our monitoring programs using a simple toy model of the propagation of accretion bursts through the envelope, which we also use to further explore how the properties of the envelope and observational setup affect the burst response. The remainder of this paper is organized as follows. In Section 2, we describe our variable protostar targets and the ALMA, SMA, and JCMT observations, while in Section 3, we provide the details of our data reduction and present light curves of our targets. In Section 4, we develop a toy model to interpret the SMA and JCMT observations of EC 53, and this is followed in Section 5 by a further exploration with the toy model of the observation of generic accretion bursts. We then discuss our results and observational\/modeling caveats in Section 6, and finish with a brief summary of our major conclusions in Section 7.","Citation Text":["Baek et al. 2020"],"Citation Start End":[[718,734]]} {"Identifier":"2021AandA...653A.111R__Duncan_et_al._(2019)_Instance_1","Paragraph":"Figure 6 shows the merger rate density computed with Eq. (9) for each of the data introduced in Sect. 4.2 and for the two z >  4 ALPINE bins. For the sake of simplicity, in this case we report only the data points obtained by adopting the Kitzbichler & White (2008) prescription for the merger timescale. When using the TMM(z) redshift evolution from Jiang et al. (2014) and Snyder et al. (2017), we obtain similar trends but shifted to higher merger rate densities. The error bar on each point is computed by propagating the merger fraction and number density uncertainties on Eq. (9). At 1 ≲ z ≲ 5, Duncan et al. (2019) found that the volume-averaged merger rate is quite constant. On the other hand, from our data we find a slight decrease both at z   1 and at z >  4. At these early epochs, this difference could be caused by the poor constraints on the GSMFs adopted by Duncan et al. (2019) which result in large uncertainties on their data, making it impossible to draw robust conclusions at z ∼ 5. Nevertheless, our derived merger rate densities are in agreement, within the uncertainties, with other results derived in the literature. For example, Mundy et al. (2017) studied the evolution of the merger rate density up to z ∼ 3.5 for a large sample of log(M*\/M⊙)> 10 galaxies. They found that, for close pairs with projected separations 5   rp   20 kpc, the ΓMM(z) evolution is better described by a power-law of the form Γ0(1 + z)γ, with \n\n\n\n\nΓ\n0\n\n=\n1\n.\n\n64\n\n−\n0.41\n\n\n+\n0.58\n\n\n×\n\n10\n\n−\n4\n\n\n\n\n$ \\Gamma_0 = 1.64^{+0.58}_{-0.41} \\times 10^{-4} $\n\n\n and \n\n\n\nγ\n=\n\n\n0.48\n\n\n−\n1.15\n\n\n+\n1.00\n\n\n\n\n$ \\gamma = {0.48}^{+1.00}_{-1.15} $\n\n\n. We report their results, along with the uncertainties, in Fig. 6 and extrapolate them to the redshifts explored by ALPINE. As evident, our data points are comparable with the results by Mundy et al. (2017). If we also fit our merger rate densities (derived assuming the Kitzbichler & White (2008) merger timescale) with a power-law function we obtain Γ0 = (2.40 ± 0.63) × 10−4 and γ = −0.16 ± 0.23, that are consistent with the above outcomes. The power-law fit on the data computed with the timescales by Jiang et al. (2014) is in agreement with the Mundy et al. (2017) findings, as well. If we instead consider the results obtained with the Snyder et al. (2017) timescale, we find a rapid increase of the merger rate density with redshift, which departs from the upper envelope of Mundy et al. (2017) already at z ≳ 1.","Citation Text":["Duncan et al. (2019)"],"Citation Start End":[[601,621]]} {"Identifier":"2021AandA...653A.111R__Duncan_et_al._(2019)_Instance_2","Paragraph":"Figure 6 shows the merger rate density computed with Eq. (9) for each of the data introduced in Sect. 4.2 and for the two z >  4 ALPINE bins. For the sake of simplicity, in this case we report only the data points obtained by adopting the Kitzbichler & White (2008) prescription for the merger timescale. When using the TMM(z) redshift evolution from Jiang et al. (2014) and Snyder et al. (2017), we obtain similar trends but shifted to higher merger rate densities. The error bar on each point is computed by propagating the merger fraction and number density uncertainties on Eq. (9). At 1 ≲ z ≲ 5, Duncan et al. (2019) found that the volume-averaged merger rate is quite constant. On the other hand, from our data we find a slight decrease both at z   1 and at z >  4. At these early epochs, this difference could be caused by the poor constraints on the GSMFs adopted by Duncan et al. (2019) which result in large uncertainties on their data, making it impossible to draw robust conclusions at z ∼ 5. Nevertheless, our derived merger rate densities are in agreement, within the uncertainties, with other results derived in the literature. For example, Mundy et al. (2017) studied the evolution of the merger rate density up to z ∼ 3.5 for a large sample of log(M*\/M⊙)> 10 galaxies. They found that, for close pairs with projected separations 5   rp   20 kpc, the ΓMM(z) evolution is better described by a power-law of the form Γ0(1 + z)γ, with \n\n\n\n\nΓ\n0\n\n=\n1\n.\n\n64\n\n−\n0.41\n\n\n+\n0.58\n\n\n×\n\n10\n\n−\n4\n\n\n\n\n$ \\Gamma_0 = 1.64^{+0.58}_{-0.41} \\times 10^{-4} $\n\n\n and \n\n\n\nγ\n=\n\n\n0.48\n\n\n−\n1.15\n\n\n+\n1.00\n\n\n\n\n$ \\gamma = {0.48}^{+1.00}_{-1.15} $\n\n\n. We report their results, along with the uncertainties, in Fig. 6 and extrapolate them to the redshifts explored by ALPINE. As evident, our data points are comparable with the results by Mundy et al. (2017). If we also fit our merger rate densities (derived assuming the Kitzbichler & White (2008) merger timescale) with a power-law function we obtain Γ0 = (2.40 ± 0.63) × 10−4 and γ = −0.16 ± 0.23, that are consistent with the above outcomes. The power-law fit on the data computed with the timescales by Jiang et al. (2014) is in agreement with the Mundy et al. (2017) findings, as well. If we instead consider the results obtained with the Snyder et al. (2017) timescale, we find a rapid increase of the merger rate density with redshift, which departs from the upper envelope of Mundy et al. (2017) already at z ≳ 1.","Citation Text":["Duncan et al. (2019)"],"Citation Start End":[[875,895]]} {"Identifier":"2021AandA...653A.11Kitzbichler_&_White_(2008)_Instance_1","Paragraph":"Figure 6 shows the merger rate density computed with Eq. (9) for each of the data introduced in Sect. 4.2 and for the two z >  4 ALPINE bins. For the sake of simplicity, in this case we report only the data points obtained by adopting the Kitzbichler & White (2008) prescription for the merger timescale. When using the TMM(z) redshift evolution from Jiang et al. (2014) and Snyder et al. (2017), we obtain similar trends but shifted to higher merger rate densities. The error bar on each point is computed by propagating the merger fraction and number density uncertainties on Eq. (9). At 1 ≲ z ≲ 5, Duncan et al. (2019) found that the volume-averaged merger rate is quite constant. On the other hand, from our data we find a slight decrease both at z   1 and at z >  4. At these early epochs, this difference could be caused by the poor constraints on the GSMFs adopted by Duncan et al. (2019) which result in large uncertainties on their data, making it impossible to draw robust conclusions at z ∼ 5. Nevertheless, our derived merger rate densities are in agreement, within the uncertainties, with other results derived in the literature. For example, Mundy et al. (2017) studied the evolution of the merger rate density up to z ∼ 3.5 for a large sample of log(M*\/M⊙)> 10 galaxies. They found that, for close pairs with projected separations 5   rp   20 kpc, the ΓMM(z) evolution is better described by a power-law of the form Γ0(1 + z)γ, with \n\n\n\n\nΓ\n0\n\n=\n1\n.\n\n64\n\n−\n0.41\n\n\n+\n0.58\n\n\n×\n\n10\n\n−\n4\n\n\n\n\n$ \\Gamma_0 = 1.64^{+0.58}_{-0.41} \\times 10^{-4} $\n\n\n and \n\n\n\nγ\n=\n\n\n0.48\n\n\n−\n1.15\n\n\n+\n1.00\n\n\n\n\n$ \\gamma = {0.48}^{+1.00}_{-1.15} $\n\n\n. We report their results, along with the uncertainties, in Fig. 6 and extrapolate them to the redshifts explored by ALPINE. As evident, our data points are comparable with the results by Mundy et al. (2017). If we also fit our merger rate densities (derived assuming the Kitzbichler & White (2008) merger timescale) with a power-law function we obtain Γ0 = (2.40 ± 0.63) × 10−4 and γ = −0.16 ± 0.23, that are consistent with the above outcomes. The power-law fit on the data computed with the timescales by Jiang et al. (2014) is in agreement with the Mundy et al. (2017) findings, as well. If we instead consider the results obtained with the Snyder et al. (2017) timescale, we find a rapid increase of the merger rate density with redshift, which departs from the upper envelope of Mundy et al. (2017) already at z ≳ 1.","Citation Text":["Kitzbichler & White (2008)"],"Citation Start End":[[239,265]]} {"Identifier":"2021AandA...656A..18H__Gurnett_et_al._1983_Instance_1","Paragraph":"During this first gravity assist manoeuvre of Venus, the Solar Orbiter RPW instrument also detected dust impacts inside the planet’s induced magnetosphere (Fig. 10). In the absence of dedicated dust detectors, the electric antenna measurements provide the only opportunity to monitor dust particles in the space plasma environment. This method has been widely applied since the 1980s allowing to estimate the mass and size distribution of the impacting dust particles from the observed characteristics of the electric field signal (Gurnett et al. 1997; Meyer-Vernet 2001; Ye et al. 2014, 2018). One of the main mechanisms believed to convert the particle’s kinetic energy of the dust into an electrical signal is the impact ionization process which generates clouds of electrons and ions around the spacecraft body (Gurnett et al. 1983; Aubier et al. 1983; Meyer-Vernet 1985). Because of the very large relative velocity between the spacecraft and the particles, when a dust particle hits the spacecraft, it instantly vaporizes, forming a hot ionized gas with free electrons and positive or negative ions that expand away from the impact site (Drapatz & Michel 1974). These charged particles are hence attracted to, or repulsed from, the spacecraft surface depending on its electric potential relative to the surrounding ambient plasma. This induces an abrupt changes in the spacecraft potential which is then observed in the voltage data (e.g., escaping electrons generate a positive spacecraft signal). Recently, Mann et al. (2019) reviewed our current knowledge on dust antenna measurements, modeling works, and their prospect to inner heliospheric missions. Since TDS is designed to capture waveforms snapshots, it is well adapted to resolve voltage spikes associated with dust impacts. Thereby, Zaslavsky et al. (2021) provided a first analysis of dust measurements recorded by TDS, along Solar Orbiter’s orbit, with promising results on the impact rate and dust grains radial velocities.","Citation Text":["Gurnett et al. 1983"],"Citation Start End":[[816,835]]} {"Identifier":"2021AandA...656A..1Mann_et_al._(2019)_Instance_1","Paragraph":"During this first gravity assist manoeuvre of Venus, the Solar Orbiter RPW instrument also detected dust impacts inside the planet’s induced magnetosphere (Fig. 10). In the absence of dedicated dust detectors, the electric antenna measurements provide the only opportunity to monitor dust particles in the space plasma environment. This method has been widely applied since the 1980s allowing to estimate the mass and size distribution of the impacting dust particles from the observed characteristics of the electric field signal (Gurnett et al. 1997; Meyer-Vernet 2001; Ye et al. 2014, 2018). One of the main mechanisms believed to convert the particle’s kinetic energy of the dust into an electrical signal is the impact ionization process which generates clouds of electrons and ions around the spacecraft body (Gurnett et al. 1983; Aubier et al. 1983; Meyer-Vernet 1985). Because of the very large relative velocity between the spacecraft and the particles, when a dust particle hits the spacecraft, it instantly vaporizes, forming a hot ionized gas with free electrons and positive or negative ions that expand away from the impact site (Drapatz & Michel 1974). These charged particles are hence attracted to, or repulsed from, the spacecraft surface depending on its electric potential relative to the surrounding ambient plasma. This induces an abrupt changes in the spacecraft potential which is then observed in the voltage data (e.g., escaping electrons generate a positive spacecraft signal). Recently, Mann et al. (2019) reviewed our current knowledge on dust antenna measurements, modeling works, and their prospect to inner heliospheric missions. Since TDS is designed to capture waveforms snapshots, it is well adapted to resolve voltage spikes associated with dust impacts. Thereby, Zaslavsky et al. (2021) provided a first analysis of dust measurements recorded by TDS, along Solar Orbiter’s orbit, with promising results on the impact rate and dust grains radial velocities.","Citation Text":["Mann et al. (2019)"],"Citation Start End":[[1515,1533]]} {"Identifier":"2018ApJ...855...48Q__Hogerheijde_et_al._1995_Instance_1","Paragraph":"The Orion Bar is probably the best studied PDR in our Galaxy. It is located between the Orion Molecular Cloud 1 and the H ii region excited by the Trapezium cluster, and is exposed to an FUV field a few 104 times the mean interstellar radiation field. Owing to its proximity (417 pc, Menten et al. 2007) and nearly edge-on orientation, the Bar provides an ideal laboratory for testing PDR models (e.g., Jansen et al. 1995; Gorti & Hollenbach 2002; Andree-Labsch et al. 2017) and a primary target for observational studies of physical and chemical structures of PDRs (e.g., Tielens et al. 1993; Walmsley et al. 2000; van der Wiel et al. 2009; Arab et al. 2012; Peng et al. 2012; Goicoechea et al. 2016; Nagy et al. 2017). Observations of various molecular spectral lines have shown that the emissions could be better interpreted with an inhomogeneous density structure containing an extended and relatively low density (\n\n\n\n\n\n cm−3) medium and a compact and high-density (\n\n\n\n\n\n cm−3) component (e.g., Hogerheijde et al. 1995; Young Owl et al. 2000; Leurini et al. 2006, 2010; Goicoechea et al. 2016). However, due to the scarcity of high-resolution observations capable of spatially resolving the density structure, the nature of the high-density clumps or condensations is still not well understood. Lis & Schilke (2003) mapped the Bar in H13CN (1–0) with the Plateau de Bure Interferometer (PdBI) at an angular resolution of about 5″, and detected 10 dense clumps. They proposed that the H13CN clumps are in virial equilibrium and may be collapsing to form stars. Goicoechea et al. (2016) performed Atacama Large Millimeter\/submillimeter Array HCO+ (4–3) observations of the Bar and detected over-dense substructures close to the cloud edge, and found that the substructures have masses much lower than the mass needed to make them gravitationally unstable. These two interferometric observations both target molecular spectral lines. A high-resolution map of the dust continuum emission of the Bar, which is highly desirable in constraining the mass and density of the dense condensations, is still lacking. Here we report our Submillimeter Array (SMA) observations of the dust continuum and molecular spectral line observations of the Bar.","Citation Text":["Hogerheijde et al. 1995"],"Citation Start End":[[1001,1024]]} {"Identifier":"2018ApJ...855...48QJansen_et_al._1995_Instance_1","Paragraph":"The Orion Bar is probably the best studied PDR in our Galaxy. It is located between the Orion Molecular Cloud 1 and the H ii region excited by the Trapezium cluster, and is exposed to an FUV field a few 104 times the mean interstellar radiation field. Owing to its proximity (417 pc, Menten et al. 2007) and nearly edge-on orientation, the Bar provides an ideal laboratory for testing PDR models (e.g., Jansen et al. 1995; Gorti & Hollenbach 2002; Andree-Labsch et al. 2017) and a primary target for observational studies of physical and chemical structures of PDRs (e.g., Tielens et al. 1993; Walmsley et al. 2000; van der Wiel et al. 2009; Arab et al. 2012; Peng et al. 2012; Goicoechea et al. 2016; Nagy et al. 2017). Observations of various molecular spectral lines have shown that the emissions could be better interpreted with an inhomogeneous density structure containing an extended and relatively low density (\n\n\n\n\n\n cm−3) medium and a compact and high-density (\n\n\n\n\n\n cm−3) component (e.g., Hogerheijde et al. 1995; Young Owl et al. 2000; Leurini et al. 2006, 2010; Goicoechea et al. 2016). However, due to the scarcity of high-resolution observations capable of spatially resolving the density structure, the nature of the high-density clumps or condensations is still not well understood. Lis & Schilke (2003) mapped the Bar in H13CN (1–0) with the Plateau de Bure Interferometer (PdBI) at an angular resolution of about 5″, and detected 10 dense clumps. They proposed that the H13CN clumps are in virial equilibrium and may be collapsing to form stars. Goicoechea et al. (2016) performed Atacama Large Millimeter\/submillimeter Array HCO+ (4–3) observations of the Bar and detected over-dense substructures close to the cloud edge, and found that the substructures have masses much lower than the mass needed to make them gravitationally unstable. These two interferometric observations both target molecular spectral lines. A high-resolution map of the dust continuum emission of the Bar, which is highly desirable in constraining the mass and density of the dense condensations, is still lacking. Here we report our Submillimeter Array (SMA) observations of the dust continuum and molecular spectral line observations of the Bar.","Citation Text":["Jansen et al. 1995"],"Citation Start End":[[403,421]]} {"Identifier":"2016MNRAS.458.2509B___2011b_Instance_1","Paragraph":"The majority of GPS pulsars are characterized by high dispersion measure (DM > 200 pc cm−3), which may very well be a coincidence of the specialized environments that harbour them. The conventional flux measurement techniques which rely on estimating the baseline level of the pulse profile may be affected by interstellar scattering which results in smearing of the pulse across the entire period. In some cases, when the pulse broadening time is a significant fraction of the pulse period (30 per cent or more) one can see a relatively sharp pulse, but at the same time the extended scattering tail may obscure the real baseline level, which leads to an underestimation of the pulsar flux. For pulsars with DMs in 200–300 pc cm−3 range this usually happens between 300 and 600 MHz (Lewandowski et al. 2013, 2015a). This leads to a somewhat pseudo-correlation between high DM and GPS pulsars (Kijak et al. 2007, 2011b) where serious underestimation of the flux at lower frequencies for high DM pulsars may give rise to an inverted spectra. The interferometric imaging technique provide a more robust measurement of the pulsar flux owing to the baseline lying at zero level thereby reducing errors made during the baseline subtraction. Dembska et al. (2015b), D15 hereafter, used the imaging technique to measure the flux of six high DM pulsars at 610 MHz to explore their suspected GPS nature. Their studies revealed that in four of the six cases the measured flux was underestimated due to scattering effects and the corrected flux followed a normal power-law spectra. In pulsar B1823−13 they confirmed the presence of GPS characteristics. However, the case of PSR B1800−21 defied expectations as the interferometric flux measurements turned out to be significantly lower than the earlier measurements using conventional methods. This gave rise to various questions regarding the spectral nature of this pulsar. There was also a possibility of the two measurement techniques being incompatible and errors during the measurement processes.","Citation Text":["Kijak et al.","2011b"],"Citation Start End":[[894,906],[913,918]]} {"Identifier":"2016MNRAS.458.2509BDembska_et_al._(2015b)_Instance_1","Paragraph":"The majority of GPS pulsars are characterized by high dispersion measure (DM > 200 pc cm−3), which may very well be a coincidence of the specialized environments that harbour them. The conventional flux measurement techniques which rely on estimating the baseline level of the pulse profile may be affected by interstellar scattering which results in smearing of the pulse across the entire period. In some cases, when the pulse broadening time is a significant fraction of the pulse period (30 per cent or more) one can see a relatively sharp pulse, but at the same time the extended scattering tail may obscure the real baseline level, which leads to an underestimation of the pulsar flux. For pulsars with DMs in 200–300 pc cm−3 range this usually happens between 300 and 600 MHz (Lewandowski et al. 2013, 2015a). This leads to a somewhat pseudo-correlation between high DM and GPS pulsars (Kijak et al. 2007, 2011b) where serious underestimation of the flux at lower frequencies for high DM pulsars may give rise to an inverted spectra. The interferometric imaging technique provide a more robust measurement of the pulsar flux owing to the baseline lying at zero level thereby reducing errors made during the baseline subtraction. Dembska et al. (2015b), D15 hereafter, used the imaging technique to measure the flux of six high DM pulsars at 610 MHz to explore their suspected GPS nature. Their studies revealed that in four of the six cases the measured flux was underestimated due to scattering effects and the corrected flux followed a normal power-law spectra. In pulsar B1823−13 they confirmed the presence of GPS characteristics. However, the case of PSR B1800−21 defied expectations as the interferometric flux measurements turned out to be significantly lower than the earlier measurements using conventional methods. This gave rise to various questions regarding the spectral nature of this pulsar. There was also a possibility of the two measurement techniques being incompatible and errors during the measurement processes.","Citation Text":["Dembska et al. (2015b)"],"Citation Start End":[[1236,1258]]} {"Identifier":"2015AandA...581A..85P__Codella_et_al._2014a_Instance_1","Paragraph":"The HH 212 region in Orion (at 450 pc) can be considered an ideal laboratory to investigate the interplay of infall, outflow, and rotation in the earliest evolutionary phases of the star forming process. HH 212 is a low-mass Class 0 source driving a symmetric and bipolar jet extensively observed in typical molecular tracers such as H2, SiO, and CO (e.g. Zinnecker et al. 1998). High-spatial resolution observations (down to \\hbox{${\\simeq}0\\farcs3{-}0\\farcs4$}≃ 0 .̋ 3−0 .̋ 4) performed with the SubMillimeter Array (SMA; Lee et al. 2006, 2007a, 2008), the IRAM Plateau de Bure (PdB) interferometer (Codella et al. 2007; Cabrit et al. 2007, 2012), and the Atacama Large Millimeter Array (ALMA; see Lee et al. 2014; Codella et al. 2014a) reveal the inner ± 1″−2″ = 450−900 AU collimated jet (width ≃100 AU) close to the protostar. HH 212 is also associated with a flattened rotating envelope in the equator perpendicular to the jet axis observed firstly with the NRAO Very Large Array (VLA) in NH3 emission by Wiseman et al. (2001) on 6000 AU scales. More recent SMA and ALMA observations in the CO isotopologues and HCO+ on ~2000, 800 AU scales indicates that the flattened envelope is rotating and infalling onto the central source, and can therefore be identified as a pseudo-disk according to magnetised core collapse models (Lee et al. 2006, 2014). In addition, a compact (≤120 AU), optically thick dust peak is observed by Codella et al. (2007), Lee et al. (2006, 2014) and attributed to an edge-on disk rather than the inner envelope. This seems to be confirmed by HCO+ and C17O emission showing signatures of a compact disk of radius ~90 AU Keplerian rotating around a source of ≃0.2−0.3 M⊙ (Lee et al. 2014; Codella et al. 2014a). Keplerian rotating disks had previously only been observed towards other three Class 0 objects: IRAS 4A2 (Choi et al. 2010), L1527 (Tobin et al. 2012; Sakai et al. 2014), and VLA1623A (Murillo et al. 2013), but HH 212 can be considered as the only object clearly revealing both a disk and a fast collimated jet, calling for further observations aimed to characterise its inner regions. ","Citation Text":["Codella et al. 2014a"],"Citation Start End":[[717,737]]} {"Identifier":"2015AandA...581A..85P__Codella_et_al._2014a_Instance_2","Paragraph":"The HH 212 region in Orion (at 450 pc) can be considered an ideal laboratory to investigate the interplay of infall, outflow, and rotation in the earliest evolutionary phases of the star forming process. HH 212 is a low-mass Class 0 source driving a symmetric and bipolar jet extensively observed in typical molecular tracers such as H2, SiO, and CO (e.g. Zinnecker et al. 1998). High-spatial resolution observations (down to \\hbox{${\\simeq}0\\farcs3{-}0\\farcs4$}≃ 0 .̋ 3−0 .̋ 4) performed with the SubMillimeter Array (SMA; Lee et al. 2006, 2007a, 2008), the IRAM Plateau de Bure (PdB) interferometer (Codella et al. 2007; Cabrit et al. 2007, 2012), and the Atacama Large Millimeter Array (ALMA; see Lee et al. 2014; Codella et al. 2014a) reveal the inner ± 1″−2″ = 450−900 AU collimated jet (width ≃100 AU) close to the protostar. HH 212 is also associated with a flattened rotating envelope in the equator perpendicular to the jet axis observed firstly with the NRAO Very Large Array (VLA) in NH3 emission by Wiseman et al. (2001) on 6000 AU scales. More recent SMA and ALMA observations in the CO isotopologues and HCO+ on ~2000, 800 AU scales indicates that the flattened envelope is rotating and infalling onto the central source, and can therefore be identified as a pseudo-disk according to magnetised core collapse models (Lee et al. 2006, 2014). In addition, a compact (≤120 AU), optically thick dust peak is observed by Codella et al. (2007), Lee et al. (2006, 2014) and attributed to an edge-on disk rather than the inner envelope. This seems to be confirmed by HCO+ and C17O emission showing signatures of a compact disk of radius ~90 AU Keplerian rotating around a source of ≃0.2−0.3 M⊙ (Lee et al. 2014; Codella et al. 2014a). Keplerian rotating disks had previously only been observed towards other three Class 0 objects: IRAS 4A2 (Choi et al. 2010), L1527 (Tobin et al. 2012; Sakai et al. 2014), and VLA1623A (Murillo et al. 2013), but HH 212 can be considered as the only object clearly revealing both a disk and a fast collimated jet, calling for further observations aimed to characterise its inner regions. ","Citation Text":["Codella et al. 2014a"],"Citation Start End":[[1718,1738]]} {"Identifier":"2015AandA...581A..8Zinnecker_et_al._1998_Instance_1","Paragraph":"The HH 212 region in Orion (at 450 pc) can be considered an ideal laboratory to investigate the interplay of infall, outflow, and rotation in the earliest evolutionary phases of the star forming process. HH 212 is a low-mass Class 0 source driving a symmetric and bipolar jet extensively observed in typical molecular tracers such as H2, SiO, and CO (e.g. Zinnecker et al. 1998). High-spatial resolution observations (down to \\hbox{${\\simeq}0\\farcs3{-}0\\farcs4$}≃ 0 .̋ 3−0 .̋ 4) performed with the SubMillimeter Array (SMA; Lee et al. 2006, 2007a, 2008), the IRAM Plateau de Bure (PdB) interferometer (Codella et al. 2007; Cabrit et al. 2007, 2012), and the Atacama Large Millimeter Array (ALMA; see Lee et al. 2014; Codella et al. 2014a) reveal the inner ± 1″−2″ = 450−900 AU collimated jet (width ≃100 AU) close to the protostar. HH 212 is also associated with a flattened rotating envelope in the equator perpendicular to the jet axis observed firstly with the NRAO Very Large Array (VLA) in NH3 emission by Wiseman et al. (2001) on 6000 AU scales. More recent SMA and ALMA observations in the CO isotopologues and HCO+ on ~2000, 800 AU scales indicates that the flattened envelope is rotating and infalling onto the central source, and can therefore be identified as a pseudo-disk according to magnetised core collapse models (Lee et al. 2006, 2014). In addition, a compact (≤120 AU), optically thick dust peak is observed by Codella et al. (2007), Lee et al. (2006, 2014) and attributed to an edge-on disk rather than the inner envelope. This seems to be confirmed by HCO+ and C17O emission showing signatures of a compact disk of radius ~90 AU Keplerian rotating around a source of ≃0.2−0.3 M⊙ (Lee et al. 2014; Codella et al. 2014a). Keplerian rotating disks had previously only been observed towards other three Class 0 objects: IRAS 4A2 (Choi et al. 2010), L1527 (Tobin et al. 2012; Sakai et al. 2014), and VLA1623A (Murillo et al. 2013), but HH 212 can be considered as the only object clearly revealing both a disk and a fast collimated jet, calling for further observations aimed to characterise its inner regions. ","Citation Text":["Zinnecker et al. 1998"],"Citation Start End":[[356,377]]} {"Identifier":"2015AandA...581A..8Wiseman_et_al._(2001)_Instance_1","Paragraph":"The HH 212 region in Orion (at 450 pc) can be considered an ideal laboratory to investigate the interplay of infall, outflow, and rotation in the earliest evolutionary phases of the star forming process. HH 212 is a low-mass Class 0 source driving a symmetric and bipolar jet extensively observed in typical molecular tracers such as H2, SiO, and CO (e.g. Zinnecker et al. 1998). High-spatial resolution observations (down to \\hbox{${\\simeq}0\\farcs3{-}0\\farcs4$}≃ 0 .̋ 3−0 .̋ 4) performed with the SubMillimeter Array (SMA; Lee et al. 2006, 2007a, 2008), the IRAM Plateau de Bure (PdB) interferometer (Codella et al. 2007; Cabrit et al. 2007, 2012), and the Atacama Large Millimeter Array (ALMA; see Lee et al. 2014; Codella et al. 2014a) reveal the inner ± 1″−2″ = 450−900 AU collimated jet (width ≃100 AU) close to the protostar. HH 212 is also associated with a flattened rotating envelope in the equator perpendicular to the jet axis observed firstly with the NRAO Very Large Array (VLA) in NH3 emission by Wiseman et al. (2001) on 6000 AU scales. More recent SMA and ALMA observations in the CO isotopologues and HCO+ on ~2000, 800 AU scales indicates that the flattened envelope is rotating and infalling onto the central source, and can therefore be identified as a pseudo-disk according to magnetised core collapse models (Lee et al. 2006, 2014). In addition, a compact (≤120 AU), optically thick dust peak is observed by Codella et al. (2007), Lee et al. (2006, 2014) and attributed to an edge-on disk rather than the inner envelope. This seems to be confirmed by HCO+ and C17O emission showing signatures of a compact disk of radius ~90 AU Keplerian rotating around a source of ≃0.2−0.3 M⊙ (Lee et al. 2014; Codella et al. 2014a). Keplerian rotating disks had previously only been observed towards other three Class 0 objects: IRAS 4A2 (Choi et al. 2010), L1527 (Tobin et al. 2012; Sakai et al. 2014), and VLA1623A (Murillo et al. 2013), but HH 212 can be considered as the only object clearly revealing both a disk and a fast collimated jet, calling for further observations aimed to characterise its inner regions. ","Citation Text":["Wiseman et al. (2001)"],"Citation Start End":[[1011,1032]]} {"Identifier":"2021ApJ...920....5L__Umeda_&_Nomoto_2008_Instance_1","Paragraph":"Figure 3 shows rough upper limits of the 56Ni yields from NDAFs with outflows (blue shaded region) and CCSNe (the red and green shaded regions shows the conditions of [Mg\/Fe] = 0 and [O\/Fe] = 0 and explosion energies in the range of 1–100 or 150 B) as functions of the progenitor-star mass. The black lines denote the medians of these regions. The CCSN data are adopted from Umeda & Nomoto (2008), because it is believed that the abundances of the most metal-poor halo stars satisfy the conditions [Mg\/Fe] ≥ 0 and [O\/Fe] ≥ 0, according to observations. That means for [Mg\/Fe] 0 or [O\/Fe] 0, the 56Ni yields should be less than those shown in Figure 3 (Umeda & Nomoto 2008). It should be mentioned that the shaded regions in Figure 3 just reflect the rough upper limits of the 56Ni yields; or rather, the ability of CCSNe and NDAFs to synthesize 56Ni, because we set the terms for the fall-free approximation of the density profile, p ≥ 0.3, for the NDAF outflows, and [Mg\/Fe] = 0 and [O\/Fe] = 0 for the CCSNe. More importantly, contrary to energetic CCSNe requiring a high explosion energy, the BH-mass growth (i.e., fallback accretion) favors the condition of a low explosion energy. In other words, there is energy and matter competition between CCSN explosions and BH fallback accretion. Hence, Figure 3 indicates that the upper limits of the total 56Ni yields should depend weakly upon the explosion energy. Hypernova models can increase 56Ni yields by ten times or more relative to normal CCSNe (e.g., Nomoto et al. 2004), and have been included to investigate the galactic evolution of SN rates (e.g., De Donder & Vanbeveren 2003). In such energetic explosions, fallback accretion is generally inefficient. As well as the hypernova models (e.g., Kobayashi et al. 2020), we consider that nucleosynthesis in the NDAF outflows in the centers of faint or failed CCSNe is another plausible way to explain observations of the metal abundance in our neighborhood and the chemical evolution of galaxies. Moreover, Kobayashi et al. (2020) estimated that the proportion of failed SNe was perhaps as large as 50% early in the history of the Galaxy, which might support the consequence of the NDAF outflows on nucleosynthesis.","Citation Text":["Umeda & Nomoto (2008)"],"Citation Start End":[[375,396]]} {"Identifier":"2021ApJ...920....5L__Umeda_&_Nomoto_2008_Instance_2","Paragraph":"Figure 3 shows rough upper limits of the 56Ni yields from NDAFs with outflows (blue shaded region) and CCSNe (the red and green shaded regions shows the conditions of [Mg\/Fe] = 0 and [O\/Fe] = 0 and explosion energies in the range of 1–100 or 150 B) as functions of the progenitor-star mass. The black lines denote the medians of these regions. The CCSN data are adopted from Umeda & Nomoto (2008), because it is believed that the abundances of the most metal-poor halo stars satisfy the conditions [Mg\/Fe] ≥ 0 and [O\/Fe] ≥ 0, according to observations. That means for [Mg\/Fe] 0 or [O\/Fe] 0, the 56Ni yields should be less than those shown in Figure 3 (Umeda & Nomoto 2008). It should be mentioned that the shaded regions in Figure 3 just reflect the rough upper limits of the 56Ni yields; or rather, the ability of CCSNe and NDAFs to synthesize 56Ni, because we set the terms for the fall-free approximation of the density profile, p ≥ 0.3, for the NDAF outflows, and [Mg\/Fe] = 0 and [O\/Fe] = 0 for the CCSNe. More importantly, contrary to energetic CCSNe requiring a high explosion energy, the BH-mass growth (i.e., fallback accretion) favors the condition of a low explosion energy. In other words, there is energy and matter competition between CCSN explosions and BH fallback accretion. Hence, Figure 3 indicates that the upper limits of the total 56Ni yields should depend weakly upon the explosion energy. Hypernova models can increase 56Ni yields by ten times or more relative to normal CCSNe (e.g., Nomoto et al. 2004), and have been included to investigate the galactic evolution of SN rates (e.g., De Donder & Vanbeveren 2003). In such energetic explosions, fallback accretion is generally inefficient. As well as the hypernova models (e.g., Kobayashi et al. 2020), we consider that nucleosynthesis in the NDAF outflows in the centers of faint or failed CCSNe is another plausible way to explain observations of the metal abundance in our neighborhood and the chemical evolution of galaxies. Moreover, Kobayashi et al. (2020) estimated that the proportion of failed SNe was perhaps as large as 50% early in the history of the Galaxy, which might support the consequence of the NDAF outflows on nucleosynthesis.","Citation Text":["Umeda & Nomoto 2008"],"Citation Start End":[[654,673]]} {"Identifier":"2020ApJ...894..121M__Strauss_&_Effenberger_2017_Instance_2","Paragraph":"In the present study, the Parker (1965) cosmic-ray TPE is solved stochastically, modifying the model presented by Engelbrecht & Burger (2015b). This equation, neglecting possible sources of CRs such as the Jovian magnetosphere, is given by\n1\n\n\n\n\n\nwhere p and r denote particle momentum and position, \n\n\n\n\n\n is the omnidirectional cosmic-ray distribution function, such that the cosmic-ray differential intensity is \n\n\n\n\n\n (see, e.g., Moraal 2013), and \n\n\n\n\n\n and K denote, respectively, the solar wind velocity and heliospheric diffusion tensor. Various processes modulating an initial, boundary CR differential intensity jB are described by this TPE, including CR drift due to gradients and curvatures of the heliospheric magnetic field and along the heliospheric current sheet, diffusion (both described by the first term on the right-hand side of Equation (1)), the outward convection of cosmic rays by the solar wind (second term on the right-hand side of Equation (1)), and adiabatic cooling (third term on the right-hand side of Equation (1)). Equation (1) can be written in terms of a set of equivalent Itō SDEs (see, e.g., Strauss & Effenberger 2017, and references therein) given by\n2\n\n\n\n\n\nwith subscripts \n\n\n\n\n\n referring to heliocentric spherical polar coordinates \n\n\n\n\n\n and CR kinetic energy E, xi(t) are Itō processes (see, e.g., Gardiner 2004), and dWi satisfy a Weiner process, such that (Strauss & Effenberger 2017)\n3\n\n\n\n\n\nwhere η (t) represents a pseudo-random, Gaussian distributed number between zero and one. Pseudo-random numbers are here generated using the Mersenne Twister algorithm developed by Matsumoto & Nishimura (1998). Equation (2) is solved in the time-backward manner using the Euler–Maruyama approximation (Maruyama 1955). Therefore, the evolution of a sufficiently large number of pseudo-particles N at a particular energy\/rigidity, and at a pre-specified point in phase-space and time \n\n\n\n\n\n (e.g., at Earth), are followed to their exit positions, times, and energies at a pre-specified boundary \n\n\n\n\n\n. Then the CR intensity at the initial point can be calculated using (Strauss & Effenberger 2017)\n4\n\n\n\n\n\nusing the assumed boundary CR intensity. Note that N = 10,000 is used throughout this study. The tensor B and vector A are related to the CR transport coefficients, and are given by, e.g., Pei et al. (2010) and Engelbrecht & Burger (2015b), such that, for a fully 3D HMF,\n5\n\n\n\n\n\nwhere κ denotes one of the elements of the diffusion tensor K in Equation (1) in heliocentric spherical coordinates. The present study employs the diffusion tensor transformation proposed by Burger et al. (2008) to convert the diffusion tensor in HMF-aligned coordinates K′, given by\n6\n\n\n\n\n\nwhere parallel and perpendicular subscripts denote diffusion coefficients parallel and perpendicular to the assumed HMF, and κA the drift coefficient (see, e.g., Forman et al. 1974), to a diffusion tensor in spherical coordinates. Note that elements of the above tensor are related to the mean free paths (MFPs) discussed below by κ = vλ\/3, with v the particle speed. The vector A is given by (Engelbrecht & Burger 2015b)\n7\n\n\n\n\n\nwith Eo the CR rest-mass energy. Note that the signs of AE, as well as of the solar wind and drift speeds Vsw and Vd, are chosen so as to render explicitly the time-backward nature of the approach taken to solving Equation (2), and thus Equation (1), in this study.","Citation Text":["Strauss & Effenberger 2017"],"Citation Start End":[[1405,1431]]} {"Identifier":"2020ApJ...894..121M__Strauss_&_Effenberger_2017_Instance_3","Paragraph":"In the present study, the Parker (1965) cosmic-ray TPE is solved stochastically, modifying the model presented by Engelbrecht & Burger (2015b). This equation, neglecting possible sources of CRs such as the Jovian magnetosphere, is given by\n1\n\n\n\n\n\nwhere p and r denote particle momentum and position, \n\n\n\n\n\n is the omnidirectional cosmic-ray distribution function, such that the cosmic-ray differential intensity is \n\n\n\n\n\n (see, e.g., Moraal 2013), and \n\n\n\n\n\n and K denote, respectively, the solar wind velocity and heliospheric diffusion tensor. Various processes modulating an initial, boundary CR differential intensity jB are described by this TPE, including CR drift due to gradients and curvatures of the heliospheric magnetic field and along the heliospheric current sheet, diffusion (both described by the first term on the right-hand side of Equation (1)), the outward convection of cosmic rays by the solar wind (second term on the right-hand side of Equation (1)), and adiabatic cooling (third term on the right-hand side of Equation (1)). Equation (1) can be written in terms of a set of equivalent Itō SDEs (see, e.g., Strauss & Effenberger 2017, and references therein) given by\n2\n\n\n\n\n\nwith subscripts \n\n\n\n\n\n referring to heliocentric spherical polar coordinates \n\n\n\n\n\n and CR kinetic energy E, xi(t) are Itō processes (see, e.g., Gardiner 2004), and dWi satisfy a Weiner process, such that (Strauss & Effenberger 2017)\n3\n\n\n\n\n\nwhere η (t) represents a pseudo-random, Gaussian distributed number between zero and one. Pseudo-random numbers are here generated using the Mersenne Twister algorithm developed by Matsumoto & Nishimura (1998). Equation (2) is solved in the time-backward manner using the Euler–Maruyama approximation (Maruyama 1955). Therefore, the evolution of a sufficiently large number of pseudo-particles N at a particular energy\/rigidity, and at a pre-specified point in phase-space and time \n\n\n\n\n\n (e.g., at Earth), are followed to their exit positions, times, and energies at a pre-specified boundary \n\n\n\n\n\n. Then the CR intensity at the initial point can be calculated using (Strauss & Effenberger 2017)\n4\n\n\n\n\n\nusing the assumed boundary CR intensity. Note that N = 10,000 is used throughout this study. The tensor B and vector A are related to the CR transport coefficients, and are given by, e.g., Pei et al. (2010) and Engelbrecht & Burger (2015b), such that, for a fully 3D HMF,\n5\n\n\n\n\n\nwhere κ denotes one of the elements of the diffusion tensor K in Equation (1) in heliocentric spherical coordinates. The present study employs the diffusion tensor transformation proposed by Burger et al. (2008) to convert the diffusion tensor in HMF-aligned coordinates K′, given by\n6\n\n\n\n\n\nwhere parallel and perpendicular subscripts denote diffusion coefficients parallel and perpendicular to the assumed HMF, and κA the drift coefficient (see, e.g., Forman et al. 1974), to a diffusion tensor in spherical coordinates. Note that elements of the above tensor are related to the mean free paths (MFPs) discussed below by κ = vλ\/3, with v the particle speed. The vector A is given by (Engelbrecht & Burger 2015b)\n7\n\n\n\n\n\nwith Eo the CR rest-mass energy. Note that the signs of AE, as well as of the solar wind and drift speeds Vsw and Vd, are chosen so as to render explicitly the time-backward nature of the approach taken to solving Equation (2), and thus Equation (1), in this study.","Citation Text":["Strauss & Effenberger 2017"],"Citation Start End":[[2109,2135]]} {"Identifier":"2020ApJ...894..121M__Strauss_&_Effenberger_2017_Instance_1","Paragraph":"In the present study, the Parker (1965) cosmic-ray TPE is solved stochastically, modifying the model presented by Engelbrecht & Burger (2015b). This equation, neglecting possible sources of CRs such as the Jovian magnetosphere, is given by\n1\n\n\n\n\n\nwhere p and r denote particle momentum and position, \n\n\n\n\n\n is the omnidirectional cosmic-ray distribution function, such that the cosmic-ray differential intensity is \n\n\n\n\n\n (see, e.g., Moraal 2013), and \n\n\n\n\n\n and K denote, respectively, the solar wind velocity and heliospheric diffusion tensor. Various processes modulating an initial, boundary CR differential intensity jB are described by this TPE, including CR drift due to gradients and curvatures of the heliospheric magnetic field and along the heliospheric current sheet, diffusion (both described by the first term on the right-hand side of Equation (1)), the outward convection of cosmic rays by the solar wind (second term on the right-hand side of Equation (1)), and adiabatic cooling (third term on the right-hand side of Equation (1)). Equation (1) can be written in terms of a set of equivalent Itō SDEs (see, e.g., Strauss & Effenberger 2017, and references therein) given by\n2\n\n\n\n\n\nwith subscripts \n\n\n\n\n\n referring to heliocentric spherical polar coordinates \n\n\n\n\n\n and CR kinetic energy E, xi(t) are Itō processes (see, e.g., Gardiner 2004), and dWi satisfy a Weiner process, such that (Strauss & Effenberger 2017)\n3\n\n\n\n\n\nwhere η (t) represents a pseudo-random, Gaussian distributed number between zero and one. Pseudo-random numbers are here generated using the Mersenne Twister algorithm developed by Matsumoto & Nishimura (1998). Equation (2) is solved in the time-backward manner using the Euler–Maruyama approximation (Maruyama 1955). Therefore, the evolution of a sufficiently large number of pseudo-particles N at a particular energy\/rigidity, and at a pre-specified point in phase-space and time \n\n\n\n\n\n (e.g., at Earth), are followed to their exit positions, times, and energies at a pre-specified boundary \n\n\n\n\n\n. Then the CR intensity at the initial point can be calculated using (Strauss & Effenberger 2017)\n4\n\n\n\n\n\nusing the assumed boundary CR intensity. Note that N = 10,000 is used throughout this study. The tensor B and vector A are related to the CR transport coefficients, and are given by, e.g., Pei et al. (2010) and Engelbrecht & Burger (2015b), such that, for a fully 3D HMF,\n5\n\n\n\n\n\nwhere κ denotes one of the elements of the diffusion tensor K in Equation (1) in heliocentric spherical coordinates. The present study employs the diffusion tensor transformation proposed by Burger et al. (2008) to convert the diffusion tensor in HMF-aligned coordinates K′, given by\n6\n\n\n\n\n\nwhere parallel and perpendicular subscripts denote diffusion coefficients parallel and perpendicular to the assumed HMF, and κA the drift coefficient (see, e.g., Forman et al. 1974), to a diffusion tensor in spherical coordinates. Note that elements of the above tensor are related to the mean free paths (MFPs) discussed below by κ = vλ\/3, with v the particle speed. The vector A is given by (Engelbrecht & Burger 2015b)\n7\n\n\n\n\n\nwith Eo the CR rest-mass energy. Note that the signs of AE, as well as of the solar wind and drift speeds Vsw and Vd, are chosen so as to render explicitly the time-backward nature of the approach taken to solving Equation (2), and thus Equation (1), in this study.","Citation Text":["Strauss & Effenberger 2017"],"Citation Start End":[[1131,1157]]} {"Identifier":"2020MNRAS.498.2270B__Barker_2011_Instance_1","Paragraph":"To calculate the dissipation we must study the properties of the wave launching region near the radiative\/convective interface in these stars. In stars with convective cores, we focus on the interface of the convective envelope rather than the core, since this is found to give the maximum dissipation in the mass range we consider. In the vicinity of a radiative\/convective interface at r = rc in a stellar model, we fit the buoyancy frequency profile with the linear fit3(40)$$\\begin{eqnarray}\r\nN^2(r) = \\left(\\frac{r}{r_c}-1\\right) \\left.\\frac{\\mathrm{d}N^2}{\\mathrm{d}\\ln r}\\right|_{r=r_c}.\r\n\\end{eqnarray}$$The dynamical tide in the vicinity of r ∼ rc can then be shown to satisfy Airy’s differential equation (Goodman & Dickson 1998), and the energy flux in gravity waves can be calculated. We will omit the details of this calculation, since they have been reported elsewhere (e.g. Goodman & Dickson 1998; Barker 2011), and just quote the resulting tidal quality factor due to gravity waves, which is determined from\n(41)$$\\begin{eqnarray}\r\n\\frac{1}{Q^{\\prime }_{\\mathrm{IGW}}} = \\frac{2\\left[\\Gamma \\left(\\frac{1}{3}\\right)\\right]^2}{3^{\\frac{1}{3}}(2l+1) (l(l+1))^{\\frac{4}{3}}}\\frac{R}{GM^2} \\mathcal {G} |\\omega |^{\\frac{8}{3}}.\r\n\\end{eqnarray}$$The quantities that depend on the radiative\/convective interface region in a particular stellar model are encapsulated in the quantity\n(42)$$\\begin{eqnarray}\r\n\\mathcal {G} = \\sigma _c^2 \\rho _c r_c^5 \\left|\\frac{\\mathrm{d}N^2}{\\mathrm{d}\\ln r}\\right|_{r=r_c}^{-\\frac{1}{3}},\r\n\\end{eqnarray}$$which takes the value $\\mathcal {G}_\\odot \\approx 2\\times 10^{47}\\,\\mathrm{kg}\\,\\mathrm{m}^2\\,\\mathrm{s}^{2\/3}$ for the current Sun (in which σc = −1.18). In this expression, ρc = ρ(rc), and the parameter\n(43)$$\\begin{eqnarray}\r\n\\sigma _c=\\frac{\\omega _{\\mathrm{ dyn}}^2}{A}\\left.\\frac{\\partial \\xi _{d,r}}{\\partial r}\\right|_{r=r_c},\r\n\\end{eqnarray}$$where the derivative of the dynamical tide radial displacement ξd, r is determined by integrating the linear differential equation given in equation (3) in Goodman & Dickson (1998). Note that σc (and $Q^{\\prime }_\\mathrm{IGW}$, for that matter) is defined such that it depends on the properties of the star but not on A.","Citation Text":["Barker 2011"],"Citation Start End":[[913,924]]} {"Identifier":"2017ApJ...849..140X__Cichowolski_et_al._2009_Instance_1","Paragraph":"The selected YSOs (Class I and Class II ) are mostly concentrated in the whole ring around H ii region Sh2-104. The high density of the YSOs located in the ring show that these YSOs are physically associated with Sh2-104. The dynamical age of Sh2-104 can be used to decide whether these YSOs are triggered by the H ii region. Using a simple model described by Dyson & Williams (1980) and assuming a H ii region expanding in a homogeneous medium, we estimate the dynamical age of the H ii region as\n12\n\n\n\n\n\nwhere \n\n\n\n\n\n is the radius of the Strömgren sphere given by \n\n\n\n\n\n = \n\n\n\n\n\n, where \n\n\n\n\n\n is the ionizing luminosity, \n\n\n\n\n\n is the initial number density of the ambient medium around the H ii region, and \n\n\n\n\n\n cm3 s−1 is the hydrogen recombination coefficient to all levels above the ground level. For the ionized medium we adopt a sound velocity of \n\n\n\n\n\n km s−1. Moreover, we adopt the radius (37) of the ring as that of H ii region Sh2-104, which is obtained from Figure 11. Taking the distance of ∼4 kpc to Sh2-104 (Deharveng et al. 2003), the H ii region radius is 4.4 pc. As a rough estimate, \n\n\n\n\n\n can be determined by distributing the total molecular mass over a sphere (e.g., Zavagno et al. 2007; Cichowolski et al. 2009; Paron et al. 2009; Anderson et al. 2015; Duronea et al. 2015). The mass of the ring is \n\n\n\n\n\n. Using this mass, we only consider the number of atoms that can be ionized, so this would imply that \n\n\n\n\n\n cm−3. H ii region Sh2-104 is excited by an O6V center star (Crampton et al. 1978; Lahulla 1985). For an O6V star, the ionizing luminosity (\n\n\n\n\n\n) is \n\n\n\n\n\n s−1 (Martins et al. 2005). Inoue (2001) suggested that only half of the Lyman continuum photons from the central source in a Galactic H ii region ionize neutral hydrogen; the remainder are absorbed by dust grains within the ionized region. Finally, we obtain the ionizing luminosity of \n\n\n\n\n\n s−1. Hence, we derived a dynamical age of \n\n\n\n\n\n yr for the H ii region Sh2-104. Additionally, from the \n\n\n\n\n\n color–magnitude diagram for the selected YSOs, we derive that the majority of the YSOs have masses in the range 1.8–6.0 \n\n\n\n\n\n, and an age range of 0.15–1.0 Myr. Comparing the dynamical age of H ii region Sh2-104 with that of the YSOs shown on the ring, we conclude that these YSOs are likely to be triggered by H ii region Sh2-104. This also means that the CC or RDI processes induce the formation of these YSOs. Deharveng et al. (2003) suggested that H ii region Sh2-104 is a typical candidate for triggering star formation by the CC process.","Citation Text":["Cichowolski et al. 2009"],"Citation Start End":[[1215,1238]]} {"Identifier":"2015ApJ...807...94L__Li_&_Cao_2012_Instance_1","Paragraph":"The dominant paradigms for jet production are outlined in the works of Blandford & Znajek (1977; BZ model) and Blandford & Payne (1982; BP model). In both of the models, the large-scale ordered magnetic fields threading the accretion flow or spinning black hole are required. It is suggested that the large-scale magnetic fields may diffuse outward rapidly if the half-thickness of the accretion disk H is significantly less than the radius r (Lubow et al. 1994; Heyvaerts et al. 1996; Guan & Gammie 2009). Then, the jet discussed in our paper should be produced in a geometrically thick disk (Maccarone et al. 2003; Sikora et al. 2007; Coriat et al. 2011; Russell et al. 2011), such as the ADAF or the slim disk (Abramowicz et al. 1988). Our work focuses on the jet produced in the ADAF, for which the accretion rate is relatively low. The jet power (\n\n\n\n\n\n) in the BP and BZ models is associated with the strength of the large-scale ordered poloidal magnetic field \n\n\n\n\n\n. In the BP model, the jet power can be described as (e.g., Livio et al. 1999; Cao 2002; Li & Cao 2012)\n3\n\n\n\n\n\nwhere \n\n\n\n\n\n is the angular velocity of the disk, \n\n\n\n\n\n is the torque applied on the disk, and \n\n\n\n\n\n is introduced to describe the contribution of different radius to the jet power. In the BP model, the energy of the jet is mainly from the inner region of the disk. Then, μ should be larger than or equal to 0, i.e.,\n4\n\n\n\n\n\nThe strength of the large-scale poloidal magnetic field remains uncertain, but is believed to be associated with the accreting process (e.g., Moderski & Sikora 1996; Ghosh & Abramowicz 1997; Livio et al. 1999; Meier 2001; Nemmen et al. 2007). In addition, the strength of the small-scale magnetic field (\n\n\n\n\n\n) in the magnetohydrodynamic turbulence of the disk is usually used to estimate the strength of \n\n\n\n\n\n, i.e., \n\n\n\n\n\n in the ADAF (Livio et al. 1999; Meier 2001; Wu & Cao 2008). In the accretion flow, \n\n\n\n\n\n may be radius dependent. In order to model this behavior, we adopt (Livio et al. 1999; Meier 2001; Wu & Cao 2008; Li & Cao 2012)\n5\n\n\n\n\n\nwhere \n\n\n\n\n\n is the stress in the magnetohydrodynamic accretion flow. If the parameter s in Equation (5) is larger than 0, \n\n\n\n\n\n in the outer region will suppress the magnetorotational instability (Velikhov 1959; Chandrasekhar 1960; Balbus & Hawley 1991, 1998), which is responsible for the angular momentum transport. Then, s should be larger than or equal to 0, i.e.,\n6\n\n\n\n\n\nBased on the above discussion, Equation (3) becomes\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n are taken and ζ is a constant. In the BZ model, the variability of jet power, which is induced by the fluctuations of the magnetic field in the vicinity of black hole, does not present a significant difference to Equation (7). Then, we use Equation (7) to describe the jet power. This equation reveals that the power of the jet depends linearly on the accretion rate in the ADAF, which has been used in a number of works (e.g., Meier 2001; Nemmen et al. 2007; Martínez-Sansigre & Rawlings 2011). Equation (7) is similar to Equation (1) but with \n\n\n\n\n\n and \n\n\n\n\n\n. It was discussed previously that the variabilities based on Equation (2) (or Equation (7)) with varying γ (\n\n\n\n\n\n) do not show significant difference. Then, the variability of jet power based on Equation (7) would follow that of the accretion rate or LX except for the amplitude of the variability, which has been found in the observation of GX 339–4 (Casella et al. 2010). This fact implies that Equation (7) is applicable to describing the jet power. In our work, we take \n\n\n\n\n\n (please see the discussion in Section 3.2). In this situation, we take \n\n\n\n\n\n, which corresponds to the case in which 10% of the gravitational energy released in the accretion process enters the jet.","Citation Text":["Li & Cao 2012"],"Citation Start End":[[1062,1075]]} {"Identifier":"2015ApJ...807...94L__Li_&_Cao_2012_Instance_2","Paragraph":"The dominant paradigms for jet production are outlined in the works of Blandford & Znajek (1977; BZ model) and Blandford & Payne (1982; BP model). In both of the models, the large-scale ordered magnetic fields threading the accretion flow or spinning black hole are required. It is suggested that the large-scale magnetic fields may diffuse outward rapidly if the half-thickness of the accretion disk H is significantly less than the radius r (Lubow et al. 1994; Heyvaerts et al. 1996; Guan & Gammie 2009). Then, the jet discussed in our paper should be produced in a geometrically thick disk (Maccarone et al. 2003; Sikora et al. 2007; Coriat et al. 2011; Russell et al. 2011), such as the ADAF or the slim disk (Abramowicz et al. 1988). Our work focuses on the jet produced in the ADAF, for which the accretion rate is relatively low. The jet power (\n\n\n\n\n\n) in the BP and BZ models is associated with the strength of the large-scale ordered poloidal magnetic field \n\n\n\n\n\n. In the BP model, the jet power can be described as (e.g., Livio et al. 1999; Cao 2002; Li & Cao 2012)\n3\n\n\n\n\n\nwhere \n\n\n\n\n\n is the angular velocity of the disk, \n\n\n\n\n\n is the torque applied on the disk, and \n\n\n\n\n\n is introduced to describe the contribution of different radius to the jet power. In the BP model, the energy of the jet is mainly from the inner region of the disk. Then, μ should be larger than or equal to 0, i.e.,\n4\n\n\n\n\n\nThe strength of the large-scale poloidal magnetic field remains uncertain, but is believed to be associated with the accreting process (e.g., Moderski & Sikora 1996; Ghosh & Abramowicz 1997; Livio et al. 1999; Meier 2001; Nemmen et al. 2007). In addition, the strength of the small-scale magnetic field (\n\n\n\n\n\n) in the magnetohydrodynamic turbulence of the disk is usually used to estimate the strength of \n\n\n\n\n\n, i.e., \n\n\n\n\n\n in the ADAF (Livio et al. 1999; Meier 2001; Wu & Cao 2008). In the accretion flow, \n\n\n\n\n\n may be radius dependent. In order to model this behavior, we adopt (Livio et al. 1999; Meier 2001; Wu & Cao 2008; Li & Cao 2012)\n5\n\n\n\n\n\nwhere \n\n\n\n\n\n is the stress in the magnetohydrodynamic accretion flow. If the parameter s in Equation (5) is larger than 0, \n\n\n\n\n\n in the outer region will suppress the magnetorotational instability (Velikhov 1959; Chandrasekhar 1960; Balbus & Hawley 1991, 1998), which is responsible for the angular momentum transport. Then, s should be larger than or equal to 0, i.e.,\n6\n\n\n\n\n\nBased on the above discussion, Equation (3) becomes\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n are taken and ζ is a constant. In the BZ model, the variability of jet power, which is induced by the fluctuations of the magnetic field in the vicinity of black hole, does not present a significant difference to Equation (7). Then, we use Equation (7) to describe the jet power. This equation reveals that the power of the jet depends linearly on the accretion rate in the ADAF, which has been used in a number of works (e.g., Meier 2001; Nemmen et al. 2007; Martínez-Sansigre & Rawlings 2011). Equation (7) is similar to Equation (1) but with \n\n\n\n\n\n and \n\n\n\n\n\n. It was discussed previously that the variabilities based on Equation (2) (or Equation (7)) with varying γ (\n\n\n\n\n\n) do not show significant difference. Then, the variability of jet power based on Equation (7) would follow that of the accretion rate or LX except for the amplitude of the variability, which has been found in the observation of GX 339–4 (Casella et al. 2010). This fact implies that Equation (7) is applicable to describing the jet power. In our work, we take \n\n\n\n\n\n (please see the discussion in Section 3.2). In this situation, we take \n\n\n\n\n\n, which corresponds to the case in which 10% of the gravitational energy released in the accretion process enters the jet.","Citation Text":["Li & Cao 2012"],"Citation Start End":[[2041,2054]]} {"Identifier":"2022ApJ...929...50P__Schombert_et_al._2001_Instance_1","Paragraph":"We carried out a detailed 2D modeling of the galaxy using GALFIT (Peng et al. 2002). In that, we model the central bright component using a Sérsic profile (Sersic 1968) while the extended faint stellar envelope was modeled with an exponential profile. The best-fit models and residuals are displayed in Figure 6. The details of our GALFIT modeling is presented in Appendix C Based on the two-component modeling of the SDSS i-band image of the galaxy, we arrive at an insight revealing the nature of the galaxy’s light distribution. The best-fit model of the extended host galaxy reveals a faint, lopsided, LSB exponential profile that is presumably due to an old stellar host. The presence of an exponential profile as found in many BCDs (e.g., Papaderos et al. 2002; Lian et al. 2015), as well as in SHOC 579, is not convincing enough for a thin stellar disk; possibilities of a triaxial stellar system cannot be ignored. The central surface brightness of the disk is μ\n0 = 22 mag arcsec−2 (e.g., Brown et al. 2001; Schombert et al. 2001; Adami et al. 2006; Pahwa & Saha 2018) with a scale length of R\n\nd\n = 1.54 kpc. Note that the disk is relatively smaller in size and the scale length is similar to that of dwarf LSB galaxies (Schombert et al. 1995; Papaderos et al. 1996b; Schombert et al. 2001; Gil de Paz & Madore 2005). The Sérsic profile for the inner component has a Sérsic index of n = 1.48 and an effective radius of 217 pc. Because our GALFIT modeling is performed using the SDSS i-band image, it hence does not contain strong nebular emission lines (e.g., Hα line) for the given redshift of the galaxy. Nevertheless, the contributions from the nebular continuum cannot be ruled out. In fact, the contribution from the nebular continuum has especially been found to be significant in the SDSS i-band image (e.g., Izotov et al. 2011). Therefore, an exponential light distribution indicating a stellar-disk-like structure around the blueberry source may be a generic property of an extended nebular halo, similar to that seen in several luminous BCDs (e.g., Papaderos et al. 2002).","Citation Text":["Schombert et al. 2001"],"Citation Start End":[[1017,1038]]} {"Identifier":"2022ApJ...929...50P__Schombert_et_al._2001_Instance_2","Paragraph":"We carried out a detailed 2D modeling of the galaxy using GALFIT (Peng et al. 2002). In that, we model the central bright component using a Sérsic profile (Sersic 1968) while the extended faint stellar envelope was modeled with an exponential profile. The best-fit models and residuals are displayed in Figure 6. The details of our GALFIT modeling is presented in Appendix C Based on the two-component modeling of the SDSS i-band image of the galaxy, we arrive at an insight revealing the nature of the galaxy’s light distribution. The best-fit model of the extended host galaxy reveals a faint, lopsided, LSB exponential profile that is presumably due to an old stellar host. The presence of an exponential profile as found in many BCDs (e.g., Papaderos et al. 2002; Lian et al. 2015), as well as in SHOC 579, is not convincing enough for a thin stellar disk; possibilities of a triaxial stellar system cannot be ignored. The central surface brightness of the disk is μ\n0 = 22 mag arcsec−2 (e.g., Brown et al. 2001; Schombert et al. 2001; Adami et al. 2006; Pahwa & Saha 2018) with a scale length of R\n\nd\n = 1.54 kpc. Note that the disk is relatively smaller in size and the scale length is similar to that of dwarf LSB galaxies (Schombert et al. 1995; Papaderos et al. 1996b; Schombert et al. 2001; Gil de Paz & Madore 2005). The Sérsic profile for the inner component has a Sérsic index of n = 1.48 and an effective radius of 217 pc. Because our GALFIT modeling is performed using the SDSS i-band image, it hence does not contain strong nebular emission lines (e.g., Hα line) for the given redshift of the galaxy. Nevertheless, the contributions from the nebular continuum cannot be ruled out. In fact, the contribution from the nebular continuum has especially been found to be significant in the SDSS i-band image (e.g., Izotov et al. 2011). Therefore, an exponential light distribution indicating a stellar-disk-like structure around the blueberry source may be a generic property of an extended nebular halo, similar to that seen in several luminous BCDs (e.g., Papaderos et al. 2002).","Citation Text":["Schombert et al. 2001"],"Citation Start End":[[1278,1299]]} {"Identifier":"2019ApJ...887...22C__Lee_et_al._2011b_Instance_1","Paragraph":"In Figure 4, the peak values of LZ for the subsamples in different cuts of \n\n\n\n\n\n, obtained from Sample B, are larger (∼2000 kpc km s−1) than those expected for a distribution dominated by TD stars (∼1600 kpc kms−1, assuming the Sun’s position at R = 8.5 kpc). Sample B is selected in a range of metallicity and α-elements abundance (−0.9 [Fe\/H] − 0.6 and +0.1 [α\/Fe] +0.2) that excludes the majority of thin-disk stars (see, for example, Figure 4 in Hayden et al. (2015) and Figure 2 in Cheng et al. (2012)). In this range of abundances, however, the outer thin-disk stars have been identified, −0.7 [Fe\/H] −0.2, and 0.0 [α\/Fe] +0.2 (Lee et al. 2011b; Bovy et al. 2012b). The total number of stars in Sample B is 415, while the number of likely outer thin-disk stars, selected according to the above criteria, is 77. This means that Sample B has a contamination from “likely” outer thin-disk stars on the order of ∼18%. This would explain the large values of LZ obtained for the TD. To investigate further, we explored the trend of the mean rotational velocity, \n\n\n\n\n\n, for Sample B (−0.9 [Fe\/H] −0.6; +0.1 [α\/Fe] +0.2) as a function of metallicity. It is known that thin-disk stars show a negative rotational velocity gradient (\n\n\n\n\n\n) as the metallicity increases, while TD stars exhibit a positive or zero velocity gradient (Lee et al. 2011b). Figure 7 shows the mean Galactocentric rotational velocity, as a function of the metallicity, for Sample B, in two different intervals of vertical distance, \n\n\n\n\n\n (black), and \n\n\n\n\n\n (red). Visual inspection of this figure reveals that the mean rotational velocity has a zero or slightly positive gradient as the metallicity increases. Therefore, it is unlikely that Sample B has significant contamination from outer thin-disk stars. We conclude that in the range of abundances where Sample B is selected, the majority of the stars belong to the TD, while other works claim that in such an interval of metallicity and α-abundance, the outer thin-disk stars are still present (Lee et al. 2011b; Bovy et al. 2012b). It remains unclear the reason why these TD stars possess such large rotational velocities, requiring further investigation.","Citation Text":["Lee et al. 2011b"],"Citation Start End":[[643,659]]} {"Identifier":"2019ApJ...887...22C__Lee_et_al._2011b_Instance_2","Paragraph":"In Figure 4, the peak values of LZ for the subsamples in different cuts of \n\n\n\n\n\n, obtained from Sample B, are larger (∼2000 kpc km s−1) than those expected for a distribution dominated by TD stars (∼1600 kpc kms−1, assuming the Sun’s position at R = 8.5 kpc). Sample B is selected in a range of metallicity and α-elements abundance (−0.9 [Fe\/H] − 0.6 and +0.1 [α\/Fe] +0.2) that excludes the majority of thin-disk stars (see, for example, Figure 4 in Hayden et al. (2015) and Figure 2 in Cheng et al. (2012)). In this range of abundances, however, the outer thin-disk stars have been identified, −0.7 [Fe\/H] −0.2, and 0.0 [α\/Fe] +0.2 (Lee et al. 2011b; Bovy et al. 2012b). The total number of stars in Sample B is 415, while the number of likely outer thin-disk stars, selected according to the above criteria, is 77. This means that Sample B has a contamination from “likely” outer thin-disk stars on the order of ∼18%. This would explain the large values of LZ obtained for the TD. To investigate further, we explored the trend of the mean rotational velocity, \n\n\n\n\n\n, for Sample B (−0.9 [Fe\/H] −0.6; +0.1 [α\/Fe] +0.2) as a function of metallicity. It is known that thin-disk stars show a negative rotational velocity gradient (\n\n\n\n\n\n) as the metallicity increases, while TD stars exhibit a positive or zero velocity gradient (Lee et al. 2011b). Figure 7 shows the mean Galactocentric rotational velocity, as a function of the metallicity, for Sample B, in two different intervals of vertical distance, \n\n\n\n\n\n (black), and \n\n\n\n\n\n (red). Visual inspection of this figure reveals that the mean rotational velocity has a zero or slightly positive gradient as the metallicity increases. Therefore, it is unlikely that Sample B has significant contamination from outer thin-disk stars. We conclude that in the range of abundances where Sample B is selected, the majority of the stars belong to the TD, while other works claim that in such an interval of metallicity and α-abundance, the outer thin-disk stars are still present (Lee et al. 2011b; Bovy et al. 2012b). It remains unclear the reason why these TD stars possess such large rotational velocities, requiring further investigation.","Citation Text":["Lee et al. 2011b"],"Citation Start End":[[1341,1357]]} {"Identifier":"2019ApJ...887...22C__Lee_et_al._2011b_Instance_3","Paragraph":"In Figure 4, the peak values of LZ for the subsamples in different cuts of \n\n\n\n\n\n, obtained from Sample B, are larger (∼2000 kpc km s−1) than those expected for a distribution dominated by TD stars (∼1600 kpc kms−1, assuming the Sun’s position at R = 8.5 kpc). Sample B is selected in a range of metallicity and α-elements abundance (−0.9 [Fe\/H] − 0.6 and +0.1 [α\/Fe] +0.2) that excludes the majority of thin-disk stars (see, for example, Figure 4 in Hayden et al. (2015) and Figure 2 in Cheng et al. (2012)). In this range of abundances, however, the outer thin-disk stars have been identified, −0.7 [Fe\/H] −0.2, and 0.0 [α\/Fe] +0.2 (Lee et al. 2011b; Bovy et al. 2012b). The total number of stars in Sample B is 415, while the number of likely outer thin-disk stars, selected according to the above criteria, is 77. This means that Sample B has a contamination from “likely” outer thin-disk stars on the order of ∼18%. This would explain the large values of LZ obtained for the TD. To investigate further, we explored the trend of the mean rotational velocity, \n\n\n\n\n\n, for Sample B (−0.9 [Fe\/H] −0.6; +0.1 [α\/Fe] +0.2) as a function of metallicity. It is known that thin-disk stars show a negative rotational velocity gradient (\n\n\n\n\n\n) as the metallicity increases, while TD stars exhibit a positive or zero velocity gradient (Lee et al. 2011b). Figure 7 shows the mean Galactocentric rotational velocity, as a function of the metallicity, for Sample B, in two different intervals of vertical distance, \n\n\n\n\n\n (black), and \n\n\n\n\n\n (red). Visual inspection of this figure reveals that the mean rotational velocity has a zero or slightly positive gradient as the metallicity increases. Therefore, it is unlikely that Sample B has significant contamination from outer thin-disk stars. We conclude that in the range of abundances where Sample B is selected, the majority of the stars belong to the TD, while other works claim that in such an interval of metallicity and α-abundance, the outer thin-disk stars are still present (Lee et al. 2011b; Bovy et al. 2012b). It remains unclear the reason why these TD stars possess such large rotational velocities, requiring further investigation.","Citation Text":["Lee et al. 2011b"],"Citation Start End":[[2037,2053]]} {"Identifier":"2022ApJ...934...85A__Strumia_&_Vissani_2003_Instance_1","Paragraph":"In the previous section, we found no clusters and set the upper limit on the number of observed clusters. In this section, we consider that the clusters are originated from supernovae, and evaluate the detectable range. We use the number of neutrinos emitted from core-collapse supernovae (ccSNe) and failed ccSNe, which result in black hole formations, derived from the Nakazato model (Nakazato et al. 2013). This model provides 20 s supernova neutrino data and is parameterized by an initial mass M\ninit, metallicity Z, and shock revival time t\nrevive. The electron antineutrino flux arriving at Earth, \n\n\n\nFe¯Earth(r)\n\n, is written as (Dighe & Smirnov 2000)\n1\n\n\n\nFe¯Earth(r,E,t)=14πr2p¯d2Ne¯0dEdt+1−p¯d2Nx0dEdt,\n\nwhere r is the distance from the Earth to a supernova, \n\n\n\nd2Ne¯0\/dEdt\n\n is the number of emitted electron antineutrinos per MeV per second, d\n2\nN\n\nx0\/dEdt is that of the antineutrinos \n\n\n\nνμ¯\n\n, \n\n\n\nντ¯\n\n and \n\n\n\np¯\n\n is the survival probability, which is 0.665 (normal mass ordering) or 0.0216 (inverted mass ordering) with \n\n\n\nsin2θ12=0.320\n\n and \n\n\n\nsin2θ13=0.0216\n\n (de Salas et al. 2018). We multiply \n\n\n\nFe¯Earth(r,E,t)\n\n by the cross section of the IBD σ\nIBD(E) (Strumia & Vissani 2003), selection efficiency ϵ\neff(E), livetime ratio η\n livetime, and number of target protons in KamLAND \n\n\n\ntarget\n\n, then integrate with the time of 20 s and the neutrino energy of 1.8–111 MeV. The expected number of observed supernova events N\nKL(r) at KamLAND as a function of r is estimated from\n2\n\n\n\nNKL(r)=ηlivetimetarget×∫dtdEFe¯Earth(r,E,t)σIBD(E)ϵeff(E).\n\nActually, observed events in KamLAND follow a Poisson distribution with mean N\nKL. To reproduce the time distribution of supernova neutrinos in KamLAND, we make the probability density function (PDF) of them. We carry out MC simulation based on the above Poisson distribution and PDF, then search for a neutrino cluster that requires two DC events within a 10 s window. N\nKL yields 10–30 events for a ccSN within 10 s in case of r = 25 kpc. Here, the number of accidentally contaminated DC events in the supernova neutrino burst is negligibly small (10−5 events) within the distance we expect N\nKL > 1. These calculations provide detection probabilities as a function of distance as shown in Figure 3. We use all available parameter combinations in this estimation, thus blue and red bands include model and neutrino mass ordering uncertainties. KamLAND has a 95% probability to the supernova neutrino burst detection with the distance for r ≤ 40–59 kpc and r ≤ 65–81 kpc for the ccSN and failed ccSN, respectively. In either case, our Galaxy (r ≲ 25 kpc) is covered with a ≥99% detection probability. Consequently, this result gives an upper limit on the supernova rate within our Galaxy, which includes ccSN rate and failed ccSN rate, \n\n\n\nRSNgal0.15yr−1\n\n (90% CL) assuming that the SN rate on the Large Magellanic Cloud and Small Magellanic Cloud are much smaller than the Galactic SN rate (Tammann et al. 1994).","Citation Text":["Strumia & Vissani 2003"],"Citation Start End":[[1187,1209]]} {"Identifier":"2020ApJ...897...44S__White_&_Frenk_1991_Instance_1","Paragraph":"In the standard ΛCDM paradigm, most of the mass in the universe resides in structures known as dark matter halos. These provide the gravitational well within which cold gas collapses, forms stars, and, at a larger scale, forms progenitors of the galaxies we observe today (e.g., White & Rees 1978; Fall & Efstathiou 1980; Blumenthal et al. 1984; Frenk & White 2012; Wechsler & Tinker 2018). The dark matter halo itself forms from the gravitational collapse of initial perturbations in the density field at the very early universe (e.g., van Albada 1960, 1961; Peebles 1970; White 1976). The emergence of the hierarchical model of structure formation (Press & Schechter 1974; Gott et al. 1975; White & Rees 1978) supported by cosmological hydrodynamical simulations and semianalytical models suggests a bottom-up scenario, in which massive halos formed from a sequence of mergers (so-called merger trees) and mass accretion, as opposed to initial rapid collapse models (e.g., White & Frenk 1991; Navarro & Benz 1991; Katz et al. 1992; Kauffmann et al. 1993; Lacey & Cole 1993; Somerville & Primack 1999). Discovery of very massive galaxies at high redshifts (\n\n\n\n\n\n), which constitute most of the luminous baryonic component inside the dark matter halos, however, suggests a rapid buildup of the bulk of their stellar mass at z > 2, with intense star formation activity at early times. Submillimeter observations further confirm the starburst populations with star formation rates (SFRs) exceeding hundreds of solar masses per year (e.g., Blain et al. 2002; Capak et al. 2008; Marchesini et al. 2010; Smolčić et al. 2015). There have been many recent spectroscopic confirmations of such sources at high-redshift galaxies experiencing suppressed star formation activity (e.g., Belli et al. 2014, 2017b, 2017a, 2019; Whitaker et al. 2014; Newman et al. 2015; Glazebrook et al. 2017; Newman et al. 2018; Schreiber et al. 2018; Forrest et al. 2020; Tanaka et al. 2019; Valentino et al. 2020). To use these systems to constrain galaxy formation and evolution scenarios and study feedback and quenching mechanisms at early times requires a robust photometric selection of these objects followed by deep spectroscopic observations.","Citation Text":["White & Frenk 1991"],"Citation Start End":[[975,993]]} {"Identifier":"2020ApJ...897...44SWhite_&_Rees_1978_Instance_1","Paragraph":"In the standard ΛCDM paradigm, most of the mass in the universe resides in structures known as dark matter halos. These provide the gravitational well within which cold gas collapses, forms stars, and, at a larger scale, forms progenitors of the galaxies we observe today (e.g., White & Rees 1978; Fall & Efstathiou 1980; Blumenthal et al. 1984; Frenk & White 2012; Wechsler & Tinker 2018). The dark matter halo itself forms from the gravitational collapse of initial perturbations in the density field at the very early universe (e.g., van Albada 1960, 1961; Peebles 1970; White 1976). The emergence of the hierarchical model of structure formation (Press & Schechter 1974; Gott et al. 1975; White & Rees 1978) supported by cosmological hydrodynamical simulations and semianalytical models suggests a bottom-up scenario, in which massive halos formed from a sequence of mergers (so-called merger trees) and mass accretion, as opposed to initial rapid collapse models (e.g., White & Frenk 1991; Navarro & Benz 1991; Katz et al. 1992; Kauffmann et al. 1993; Lacey & Cole 1993; Somerville & Primack 1999). Discovery of very massive galaxies at high redshifts (\n\n\n\n\n\n), which constitute most of the luminous baryonic component inside the dark matter halos, however, suggests a rapid buildup of the bulk of their stellar mass at z > 2, with intense star formation activity at early times. Submillimeter observations further confirm the starburst populations with star formation rates (SFRs) exceeding hundreds of solar masses per year (e.g., Blain et al. 2002; Capak et al. 2008; Marchesini et al. 2010; Smolčić et al. 2015). There have been many recent spectroscopic confirmations of such sources at high-redshift galaxies experiencing suppressed star formation activity (e.g., Belli et al. 2014, 2017b, 2017a, 2019; Whitaker et al. 2014; Newman et al. 2015; Glazebrook et al. 2017; Newman et al. 2018; Schreiber et al. 2018; Forrest et al. 2020; Tanaka et al. 2019; Valentino et al. 2020). To use these systems to constrain galaxy formation and evolution scenarios and study feedback and quenching mechanisms at early times requires a robust photometric selection of these objects followed by deep spectroscopic observations.","Citation Text":["White & Rees 1978"],"Citation Start End":[[279,296]]} {"Identifier":"2020ApJ...897...44SWhite_&_Rees_1978_Instance_2","Paragraph":"In the standard ΛCDM paradigm, most of the mass in the universe resides in structures known as dark matter halos. These provide the gravitational well within which cold gas collapses, forms stars, and, at a larger scale, forms progenitors of the galaxies we observe today (e.g., White & Rees 1978; Fall & Efstathiou 1980; Blumenthal et al. 1984; Frenk & White 2012; Wechsler & Tinker 2018). The dark matter halo itself forms from the gravitational collapse of initial perturbations in the density field at the very early universe (e.g., van Albada 1960, 1961; Peebles 1970; White 1976). The emergence of the hierarchical model of structure formation (Press & Schechter 1974; Gott et al. 1975; White & Rees 1978) supported by cosmological hydrodynamical simulations and semianalytical models suggests a bottom-up scenario, in which massive halos formed from a sequence of mergers (so-called merger trees) and mass accretion, as opposed to initial rapid collapse models (e.g., White & Frenk 1991; Navarro & Benz 1991; Katz et al. 1992; Kauffmann et al. 1993; Lacey & Cole 1993; Somerville & Primack 1999). Discovery of very massive galaxies at high redshifts (\n\n\n\n\n\n), which constitute most of the luminous baryonic component inside the dark matter halos, however, suggests a rapid buildup of the bulk of their stellar mass at z > 2, with intense star formation activity at early times. Submillimeter observations further confirm the starburst populations with star formation rates (SFRs) exceeding hundreds of solar masses per year (e.g., Blain et al. 2002; Capak et al. 2008; Marchesini et al. 2010; Smolčić et al. 2015). There have been many recent spectroscopic confirmations of such sources at high-redshift galaxies experiencing suppressed star formation activity (e.g., Belli et al. 2014, 2017b, 2017a, 2019; Whitaker et al. 2014; Newman et al. 2015; Glazebrook et al. 2017; Newman et al. 2018; Schreiber et al. 2018; Forrest et al. 2020; Tanaka et al. 2019; Valentino et al. 2020). To use these systems to constrain galaxy formation and evolution scenarios and study feedback and quenching mechanisms at early times requires a robust photometric selection of these objects followed by deep spectroscopic observations.","Citation Text":["White & Rees 1978"],"Citation Start End":[[693,710]]} {"Identifier":"2020ApJ...897...44SBlain_et_al._2002_Instance_1","Paragraph":"In the standard ΛCDM paradigm, most of the mass in the universe resides in structures known as dark matter halos. These provide the gravitational well within which cold gas collapses, forms stars, and, at a larger scale, forms progenitors of the galaxies we observe today (e.g., White & Rees 1978; Fall & Efstathiou 1980; Blumenthal et al. 1984; Frenk & White 2012; Wechsler & Tinker 2018). The dark matter halo itself forms from the gravitational collapse of initial perturbations in the density field at the very early universe (e.g., van Albada 1960, 1961; Peebles 1970; White 1976). The emergence of the hierarchical model of structure formation (Press & Schechter 1974; Gott et al. 1975; White & Rees 1978) supported by cosmological hydrodynamical simulations and semianalytical models suggests a bottom-up scenario, in which massive halos formed from a sequence of mergers (so-called merger trees) and mass accretion, as opposed to initial rapid collapse models (e.g., White & Frenk 1991; Navarro & Benz 1991; Katz et al. 1992; Kauffmann et al. 1993; Lacey & Cole 1993; Somerville & Primack 1999). Discovery of very massive galaxies at high redshifts (\n\n\n\n\n\n), which constitute most of the luminous baryonic component inside the dark matter halos, however, suggests a rapid buildup of the bulk of their stellar mass at z > 2, with intense star formation activity at early times. Submillimeter observations further confirm the starburst populations with star formation rates (SFRs) exceeding hundreds of solar masses per year (e.g., Blain et al. 2002; Capak et al. 2008; Marchesini et al. 2010; Smolčić et al. 2015). There have been many recent spectroscopic confirmations of such sources at high-redshift galaxies experiencing suppressed star formation activity (e.g., Belli et al. 2014, 2017b, 2017a, 2019; Whitaker et al. 2014; Newman et al. 2015; Glazebrook et al. 2017; Newman et al. 2018; Schreiber et al. 2018; Forrest et al. 2020; Tanaka et al. 2019; Valentino et al. 2020). To use these systems to constrain galaxy formation and evolution scenarios and study feedback and quenching mechanisms at early times requires a robust photometric selection of these objects followed by deep spectroscopic observations.","Citation Text":["Blain et al. 2002"],"Citation Start End":[[1538,1555]]} {"Identifier":"2020ApJ...897...44SWhitaker_et_al._2014_Instance_1","Paragraph":"In the standard ΛCDM paradigm, most of the mass in the universe resides in structures known as dark matter halos. These provide the gravitational well within which cold gas collapses, forms stars, and, at a larger scale, forms progenitors of the galaxies we observe today (e.g., White & Rees 1978; Fall & Efstathiou 1980; Blumenthal et al. 1984; Frenk & White 2012; Wechsler & Tinker 2018). The dark matter halo itself forms from the gravitational collapse of initial perturbations in the density field at the very early universe (e.g., van Albada 1960, 1961; Peebles 1970; White 1976). The emergence of the hierarchical model of structure formation (Press & Schechter 1974; Gott et al. 1975; White & Rees 1978) supported by cosmological hydrodynamical simulations and semianalytical models suggests a bottom-up scenario, in which massive halos formed from a sequence of mergers (so-called merger trees) and mass accretion, as opposed to initial rapid collapse models (e.g., White & Frenk 1991; Navarro & Benz 1991; Katz et al. 1992; Kauffmann et al. 1993; Lacey & Cole 1993; Somerville & Primack 1999). Discovery of very massive galaxies at high redshifts (\n\n\n\n\n\n), which constitute most of the luminous baryonic component inside the dark matter halos, however, suggests a rapid buildup of the bulk of their stellar mass at z > 2, with intense star formation activity at early times. Submillimeter observations further confirm the starburst populations with star formation rates (SFRs) exceeding hundreds of solar masses per year (e.g., Blain et al. 2002; Capak et al. 2008; Marchesini et al. 2010; Smolčić et al. 2015). There have been many recent spectroscopic confirmations of such sources at high-redshift galaxies experiencing suppressed star formation activity (e.g., Belli et al. 2014, 2017b, 2017a, 2019; Whitaker et al. 2014; Newman et al. 2015; Glazebrook et al. 2017; Newman et al. 2018; Schreiber et al. 2018; Forrest et al. 2020; Tanaka et al. 2019; Valentino et al. 2020). To use these systems to constrain galaxy formation and evolution scenarios and study feedback and quenching mechanisms at early times requires a robust photometric selection of these objects followed by deep spectroscopic observations.","Citation Text":["Whitaker et al. 2014"],"Citation Start End":[[1814,1834]]} {"Identifier":"2019MNRAS.485.4150B__Piran_et_al._2013_Instance_1","Paragraph":"We calculate the expected radio fluxes following the prescriptions of Piran, Nakar & Rosswog (2013). We consider an expanding spherical, non-relativistic ejecta that collects mass from the uniform circum-merger medium with particle density n as it moves outwards with velocity v ≡ βc, where c is the speed of light. The velocity of the ejecta decreases as it collects more mass. The relation between ejecta velocity and radius (R) can be calculated by assuming that kinetic energy is conserved (see equation 14 of Piran et al. 2013):\n(2)\r\n\\begin{eqnarray*}\r\nM(R)(\\beta c)^2 \\approx E(\\ge \\beta),\r\n\\end{eqnarray*}\r\nwhere M is the collected mass at radius R from the merger, and E(≥β) is the kinetic energy of the part of the ejecta that was launched with velocities faster than βc. In our case, this means that initially only the component with 0.3c velocity affects the evolution of the ejecta front and hence the radio flux until it slows down to 0.1c where the slower component can catch up. With R and β known functions of time, we can calculate the emitted radio flux as (see equations 4 and 6 and table 2 in Piran et al. 2013)\n(3)\r\n\\begin{eqnarray*}\r\nF(t)\\approx 4\\, \\mbox{mJy}\\, R_{17}^3 n_{-1}^{15\/8} \\beta ^{19\/4} d_{200}^{-2}\\left(\\frac{\\nu }{6\\, \\mbox{GHz}}\\right)^{-3\/4},\r\n\\end{eqnarray*}\r\nwhere $R_{17}\\equiv (R\/10^{17}\\, \\mbox{cm})$, $n_{-1}\\equiv (n\/0.1\\, \\mbox{cm}^{-3})$, and $d_{200}\\equiv (d\/200\\, \\mbox{Mpc})$. We assume that the observational frequency νobs = 6 GHz is greater than both the typical synchrotron frequency of electrons in the forward shock driven by the ejecta (νm), and the synchrotron self-absorption frequency (νa; see e.g. Piran et al. 2013). We further assume that electrons and the magnetic field carry $\\epsilon _{\\rm e}\\approx \\epsilon _{\\rm m}\\sim 10{{\\ \\rm per\\ cent}}$ of the total internal energy of the shocked gas, and that the power-law index of the distribution of the accelerated electrons’ Lorentz factors is p = 2.5.","Citation Text":["Piran et al. 2013"],"Citation Start End":[[514,531]]} {"Identifier":"2019MNRAS.485.4150B__Piran_et_al._2013_Instance_2","Paragraph":"We calculate the expected radio fluxes following the prescriptions of Piran, Nakar & Rosswog (2013). We consider an expanding spherical, non-relativistic ejecta that collects mass from the uniform circum-merger medium with particle density n as it moves outwards with velocity v ≡ βc, where c is the speed of light. The velocity of the ejecta decreases as it collects more mass. The relation between ejecta velocity and radius (R) can be calculated by assuming that kinetic energy is conserved (see equation 14 of Piran et al. 2013):\n(2)\r\n\\begin{eqnarray*}\r\nM(R)(\\beta c)^2 \\approx E(\\ge \\beta),\r\n\\end{eqnarray*}\r\nwhere M is the collected mass at radius R from the merger, and E(≥β) is the kinetic energy of the part of the ejecta that was launched with velocities faster than βc. In our case, this means that initially only the component with 0.3c velocity affects the evolution of the ejecta front and hence the radio flux until it slows down to 0.1c where the slower component can catch up. With R and β known functions of time, we can calculate the emitted radio flux as (see equations 4 and 6 and table 2 in Piran et al. 2013)\n(3)\r\n\\begin{eqnarray*}\r\nF(t)\\approx 4\\, \\mbox{mJy}\\, R_{17}^3 n_{-1}^{15\/8} \\beta ^{19\/4} d_{200}^{-2}\\left(\\frac{\\nu }{6\\, \\mbox{GHz}}\\right)^{-3\/4},\r\n\\end{eqnarray*}\r\nwhere $R_{17}\\equiv (R\/10^{17}\\, \\mbox{cm})$, $n_{-1}\\equiv (n\/0.1\\, \\mbox{cm}^{-3})$, and $d_{200}\\equiv (d\/200\\, \\mbox{Mpc})$. We assume that the observational frequency νobs = 6 GHz is greater than both the typical synchrotron frequency of electrons in the forward shock driven by the ejecta (νm), and the synchrotron self-absorption frequency (νa; see e.g. Piran et al. 2013). We further assume that electrons and the magnetic field carry $\\epsilon _{\\rm e}\\approx \\epsilon _{\\rm m}\\sim 10{{\\ \\rm per\\ cent}}$ of the total internal energy of the shocked gas, and that the power-law index of the distribution of the accelerated electrons’ Lorentz factors is p = 2.5.","Citation Text":["Piran et al. 2013"],"Citation Start End":[[1113,1130]]} {"Identifier":"2019MNRAS.485.4150B__Piran_et_al._2013_Instance_3","Paragraph":"We calculate the expected radio fluxes following the prescriptions of Piran, Nakar & Rosswog (2013). We consider an expanding spherical, non-relativistic ejecta that collects mass from the uniform circum-merger medium with particle density n as it moves outwards with velocity v ≡ βc, where c is the speed of light. The velocity of the ejecta decreases as it collects more mass. The relation between ejecta velocity and radius (R) can be calculated by assuming that kinetic energy is conserved (see equation 14 of Piran et al. 2013):\n(2)\r\n\\begin{eqnarray*}\r\nM(R)(\\beta c)^2 \\approx E(\\ge \\beta),\r\n\\end{eqnarray*}\r\nwhere M is the collected mass at radius R from the merger, and E(≥β) is the kinetic energy of the part of the ejecta that was launched with velocities faster than βc. In our case, this means that initially only the component with 0.3c velocity affects the evolution of the ejecta front and hence the radio flux until it slows down to 0.1c where the slower component can catch up. With R and β known functions of time, we can calculate the emitted radio flux as (see equations 4 and 6 and table 2 in Piran et al. 2013)\n(3)\r\n\\begin{eqnarray*}\r\nF(t)\\approx 4\\, \\mbox{mJy}\\, R_{17}^3 n_{-1}^{15\/8} \\beta ^{19\/4} d_{200}^{-2}\\left(\\frac{\\nu }{6\\, \\mbox{GHz}}\\right)^{-3\/4},\r\n\\end{eqnarray*}\r\nwhere $R_{17}\\equiv (R\/10^{17}\\, \\mbox{cm})$, $n_{-1}\\equiv (n\/0.1\\, \\mbox{cm}^{-3})$, and $d_{200}\\equiv (d\/200\\, \\mbox{Mpc})$. We assume that the observational frequency νobs = 6 GHz is greater than both the typical synchrotron frequency of electrons in the forward shock driven by the ejecta (νm), and the synchrotron self-absorption frequency (νa; see e.g. Piran et al. 2013). We further assume that electrons and the magnetic field carry $\\epsilon _{\\rm e}\\approx \\epsilon _{\\rm m}\\sim 10{{\\ \\rm per\\ cent}}$ of the total internal energy of the shocked gas, and that the power-law index of the distribution of the accelerated electrons’ Lorentz factors is p = 2.5.","Citation Text":["Piran et al. 2013"],"Citation Start End":[[1662,1679]]} {"Identifier":"2015ApJ...805...37L__Liu_et_al._2008_Instance_1","Paragraph":"The equation of state is\n14\n\n\n\n\n\nwhere \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n are the gas pressure from nucleons, the radiation pressure of photons, the degeneracy pressure of electrons, and the radiation pressure of neutrinos, respectively. k, T, \n\n\n\n\n\n, a, and h are the Boltzmann constant, temperature of the disk, proton mass, radiation constant, and Planck constant, respectively. The equation can be applied anywhere on the disk to describe the pressure, but we also need an equation to completely give the vertical distributions of the density, temperature, and pressure. For simplicity, we assume the polytropic relation, i.e., \n\n\n\n\n\n, in the vertical direction, with K as a constant (e.g., Lee et al. 2005; Liu et al. 2008, 2010a, 2012a, 2013). Here we also assume the electron fraction \n\n\n\n\n\n is 0.5 (e.g., Di Matteo et al. 2002; Gu et al. 2006; Liu et al. 2014), because its influences are very limited on the structure and neutrino luminosity of the disk, unless we care about the types of neutrinos emitted from the disk (e.g., Liu et al. 2013). \n\n\n\n\n\n is the mass fraction of free nucleons, and its expression is obtained by taking \n\n\n\n\n\n as (e.g., Kohri et al. 2005)\n15\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n. \n\n\n\n\n\n is the energy density of neutrinos, which can be expressed as (e.g., Lee et al. 2005; Liu et al. 2012a)\n16\n\n\n\n\n\nwhere \n\n\n\n\n\n is the total optical depth for neutrinos, \n\n\n\n\n\n and \n\n\n\n\n\n are the absorption and scattering optical depth for neutrinos, and the subscript i runs for the three species of neutrinos \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n, which can be defined as (Di Matteo et al. 2002; Lee et al. 2005; Liu et al. 2012a)\n17\n\n\n\n\n\n\n\n18\n\n\n\n\n\nwhere \n\n\n\n\n\n is the summation of the cooling rates per unit volume due to the neutrino reactions for different neutrinos, especially the Urca processes and electron–positron pair annihilation (e.g., Di Matteo et al. 2002; Liu et al. 2007). The neutrino scattering processes include scattering by free protons, free neutrons, α-particles, and electrons (e.g., Di Matteo et al. 2002).","Citation Text":["Liu et al. 2008"],"Citation Start End":[[712,727]]} {"Identifier":"2020ApJ...897...73M__Ferinelli_et_al._2008_Instance_1","Paragraph":"AstroSat data enabled us to derive the X-ray spectrum in the 0.8–70 keV energy band as shown in Figure 7. The spectrum was fitted reasonably well using two models. The first model was defined as an absorbed Fermi–Dirac cutoff model along with a blackbody, an Fe emission line, and three Gaussian absorption lines introduced to model cyclotron scattering features and its two higher harmonics as observed in the spectrum. The CompTT model was used as the second model in combination with an Fe emission line and three Gaussian absorptions lines as defined in the first model. The CompTT model is generally used for neutron-star-based low-mass X-ray binaries such as Z-type and atoll sources with a relatively lower magnetic field (\n\n\n\n\n\n G) of the neutron star (Ferinelli et al. 2008). However, the model could also successfully define the spectrum of some of the pulsars in Be binaries, for example, Cep X-4 (Jaiswal & Naik 2015), 4U 1907+09 (Varun et al. 2019), and GRO J2058+42 (Molkov et al. 2019). The parameters derived from the two models are tabulated in Table 2. The first model estimated a blackbody temperature of 0.83 ± 0.04 keV and detected the presence of a cyclotron resonance scattering feature and its harmonics. The Comptonization model, on the other hand, enabled us to determine the input photon Wien temperature of 0.52 ± 0.02 keV, the plasma temperature of 8.22 ± 0.10 keV, and the plasma optical depth of 5.21 ± 0.12 for the phase-averaged spectra. The Wien temperature, per the CompTT model, originates far from the neutron star surface and closer to the inner accretion disk i.e., at the outer transition layer; hence, the Wien temperature is always found to be relatively lower than the neutron star blackbody temperature as it originates closer to the inner transition layer, i.e., near the surface of the neutron star (Ferinelli et al. 2008). For the CompTT model, bulk Comptonization occurs in the innermost part of the transition layer region, while thermal Comptonization is dominant in the outer transition layer and presumably within some extended region located above the accretion disk. Similar deviations were also observed in the case of Cep X-4 fitted with the CompTT model and a blackbody combined with the FDCUT model (Table 1 of Jaiswal & Naik 2015). However, the centroid energy of the cyclotron absorption features and its detected harmonics are found to be consistent within errors for the two models (Table 2).","Citation Text":["Ferinelli et al. 2008"],"Citation Start End":[[761,782]]} {"Identifier":"2020ApJ...897...73M__Ferinelli_et_al._2008_Instance_2","Paragraph":"AstroSat data enabled us to derive the X-ray spectrum in the 0.8–70 keV energy band as shown in Figure 7. The spectrum was fitted reasonably well using two models. The first model was defined as an absorbed Fermi–Dirac cutoff model along with a blackbody, an Fe emission line, and three Gaussian absorption lines introduced to model cyclotron scattering features and its two higher harmonics as observed in the spectrum. The CompTT model was used as the second model in combination with an Fe emission line and three Gaussian absorptions lines as defined in the first model. The CompTT model is generally used for neutron-star-based low-mass X-ray binaries such as Z-type and atoll sources with a relatively lower magnetic field (\n\n\n\n\n\n G) of the neutron star (Ferinelli et al. 2008). However, the model could also successfully define the spectrum of some of the pulsars in Be binaries, for example, Cep X-4 (Jaiswal & Naik 2015), 4U 1907+09 (Varun et al. 2019), and GRO J2058+42 (Molkov et al. 2019). The parameters derived from the two models are tabulated in Table 2. The first model estimated a blackbody temperature of 0.83 ± 0.04 keV and detected the presence of a cyclotron resonance scattering feature and its harmonics. The Comptonization model, on the other hand, enabled us to determine the input photon Wien temperature of 0.52 ± 0.02 keV, the plasma temperature of 8.22 ± 0.10 keV, and the plasma optical depth of 5.21 ± 0.12 for the phase-averaged spectra. The Wien temperature, per the CompTT model, originates far from the neutron star surface and closer to the inner accretion disk i.e., at the outer transition layer; hence, the Wien temperature is always found to be relatively lower than the neutron star blackbody temperature as it originates closer to the inner transition layer, i.e., near the surface of the neutron star (Ferinelli et al. 2008). For the CompTT model, bulk Comptonization occurs in the innermost part of the transition layer region, while thermal Comptonization is dominant in the outer transition layer and presumably within some extended region located above the accretion disk. Similar deviations were also observed in the case of Cep X-4 fitted with the CompTT model and a blackbody combined with the FDCUT model (Table 1 of Jaiswal & Naik 2015). However, the centroid energy of the cyclotron absorption features and its detected harmonics are found to be consistent within errors for the two models (Table 2).","Citation Text":["Ferinelli et al. 2008"],"Citation Start End":[[1846,1867]]} {"Identifier":"2015ApJ...812...21F__Chen_et_al._2012_Instance_1","Paragraph":"A clear transition in the spectra is observed at scales \n\n\n\n\n\n with a change in the spectral indices of all fields. In particular, the spectrum of the perpendicular magnetic fluctuations steepens at \n\n\n\n\n\n following a power law with a spectral index \n\n\n\n\n\n for another decade. The location of the break does not show any significant dependence on the number of particles, the spatial resolution, and the resistivity adopted, provided that a sufficient number of grid points allows us to cover approximatively a decade at sub-proton scales, i.e., that the scale at which resistive dissipation acts is sufficiently separated from the region of the break. The parallel component of the magnetic field, together with the density, follows a similar but slightly shallower slope with a spectral index of \n\n\n\n\n\n in very good agreement with observations (Chen et al. 2012, 2013b) and other simulations (Howes et al. 2011; Passot et al. 2014). As a result, magnetic fluctuations tend to become isotropic at small scales, resulting in an increase of the magnetic compressibility, as observed in the solar wind (Podesta & TenBarge 2012; Salem et al. 2012; Kiyani et al. 2013). The spectrum of the perpendicular velocity fluctuations quickly drops above \n\n\n\n\n\n without any clear power-law trend. The observation of a spectral index of \n\n\n\n\n\n has been ascribed to the effect of the electron Landau damping by previous studies (Howes et al. 2011; Passot et al. 2014); however, this cannot be the case in our simulations, where the electron kinetics is not taken into account. Alternatively, the presence of coherent structures, such as current sheets, can produce a steepening of the energy spectra (e.g., Wan et al. 2012; Karimabadi et al. 2013). The increase of intermittency at small scales, observed in our simulations, seems to confirm this path toward the dissipation. We have to note, however, that a \n\n\n\n\n\n power law for the magnetic energy and the density spectra (not far from the 2.8 found here) has been also interpreted as related to the dimensionality (1D or 2D) of the magnetic and the density intermittent structures, without invoking dissipation (Boldyrev & Perez 2012; Meyrand & Galtier 2013).","Citation Text":["Chen et al. 2012"],"Citation Start End":[[847,863]]} {"Identifier":"2015ApJ...802...93S__Norris_1984_Instance_1","Paragraph":"For the stars below \n\n\n\n\n\n, our Ca abundances are determined from the only Cai line detected, the 4226.73 Å resonance line. This line is known to produce lower Ca abundances than other Ca i lines for EMP stars, at least in part because of NLTE effects (e.g., Spite et al. 2012), leading T10 to dismiss the significance of the even lower [Ca\/Fe] ratio they derived for Scl 07-50. However, NLTE models do not agree well on the correction for the 4226.73 Å line for stars with similar atmospheric parameters to Scl 07-50 and Scl 11_1_4296, with recent predictions ranging from −0.02 dex (Starkenburg et al. 2010) to +0.21 dex (Mashonkina et al. 2007; L. Mashonkina 2014, private communication). We therefore attempted several additional tests to verify the low Ca abundances. First, we compared the Ca lines of both stars with those of the ultra metal-poor giant CD \n\n\n\n\n\n 245 (Bessell Norris 1984), which is comparable in temperature to Scl 11_1_4296 and ∼200 K warmer than Scl 07-50 (see Figure 2). Scl 11_1_4296 has weaker Ca i λ4226.73 Å and near-infrared Ca ii triplet lines than CD \n\n\n\n\n\n 245, confirming its low Ca abundance. Scl 07-50 has similar Ca K and Cai λ4226.73 Å EWs to CD \n\n\n\n\n\n 245, consistent with a lower Ca abundance given the temperature difference.5\n\n5\nThe Ca triplet lines of Scl 07-50 are stronger than those of CD \n\n\n\n\n\n 245, but NLTE and 3D corrections for those lines are much larger and even less well understood.\n Second, we compared to stars with similar parameters (after adjusting their spectroscopic temperatures according to the Frebel et al. 2013 formula) from Roederer et al. (2014). These stars were selected to have 4400 K \n\n\n\n\n\n 4900 K, \n\n\n\n\n\n, \n\n\n\n\n\n, and a detection of the Ca i resonance line, resulting in a sample of 13 stars. For this sample, Ca abundances from Ca i 4226.73 Å are 0.09 dex lower than the mean abundance from all other Ca i lines.6\n\n6\nThe only outlier where Ca i 4226.73 Å and the other lines have a significantly larger abundance difference is the coolest star, CS 22950–046, which is similar in temperature to Scl 07-50, raising the possibility of a sharp temperature dependence in the abundance derived from the resonance line. However, because the theoretical studies of Mashonkina et al. (2007) Merle et al. (2011), and Spite et al. (2012) do not indicate strong changes in NLTE corrections at \n\n\n\n\n\n K, we regard CS 22950–046 as a random outlier rather than a systematic one.\n This offset is in excellent agreement with the most recent NLTE corrections for Ca determined by Spite et al. (2012), which give 0.08 dex for \n\n\n\n\n\n K, \n\n\n\n\n\n, \n\n\n\n\n\n. Finally, we stacked the four strongest Ca i non-resonance lines and determined upper limits of \n\n\n\n\n\n dex and \n\n\n\n\n\n dex for Scl 07-50 and Scl 11_1_4296, respectively, by comparing to synthesized spectra. We therefore conclude that even after factoring in the uncertain NLTE effects, Scl 07-50 and Scl 11_1_4296 indeed have low Ca abundances.","Citation Text":["Bessell Norris 1984"],"Citation Start End":[[875,895]]} {"Identifier":"2021AandA...654A..89P__Reeves_et_al._2021a_Instance_1","Paragraph":"Therefore, we now fit the two pn spectra between 3 and 10 keV using a power-law model with Galactic absorption, a narrow neutral Fe Kα core (En = 6.4 keV and σn = 0 eV), and a disc line model (RELLINE; Dauser et al. 2010, 2013) to account for the mildly broad line. For the third component, the energy was fixed at 6.4 keV and the spin at zero (since it is not constrained). All parameters of the Fe Kα narrow component and the emissivity index for the mild relativistic Fe K line component were tied between the two epochs. From this modelling (χ2\/d.o.f. = 585.4\/668), we infer an accretion disc emissivity index lower than 2.1 and a disc inclination lower than 24.6°, which is consistent with the inclination angle inferred from the variable O VII soft X-ray emission line (\n\n\n\nθ\n=\n9\n.\n\n9\n\n−\n1.4\n\n\n+\n1.0\n\n\n\n\n$ \\theta=9.9^{+1.0}_{-1.4} $\n\n\n) arising from the accretion disc too (Reeves et al. 2021a). For the narrow core of the Fe Kα line, we measure a EWn ≲ 20 eV, which is in the lower range of the values found for type-1 AGN (∼30−200 eV; Liu & Wang 2010; Shu et al. 2010; Fukazawa et al. 2011; Ricci et al. 2014). This is consistent with the very weak covering factor of 0.06 for the putative torus, which is inferred from the ratio of the infrared to the bolometric luminosity of the source (Ezhikode et al. 2017). Moreover, the torus covering factor measured for Mrk 110 is one of the lowest reported in the Ezhikode et al. (2017) sample; this is also in agreement with the lack of Compton hump. The equivalent widths of the moderately broad Fe Kα line are EWb = 61\n\n\n\n\n\n−\n27\n\n\n+\n23\n\n\n\n$ ^{+23}_{-27} $\n\n\n eV and EWb = 43\n\n\n\n\n\n−\n27\n\n\n+\n22\n\n\n\n$ ^{+22}_{-27} $\n\n\n eV for 2019 and 2020, respectively. Likewise, if we allow the inner disc radius to be free to vary and assume a standard value of three for the disc emissivity index, as well as fixing the inclination angle at 9.9° (χ2\/d.o.f. = 585.1\/668), we infer Rin = 120\n\n\n\n\n\n−\n67\n\n\n+\n263\n\n\n\n$ ^{+263}_{-67} $\n\n\nRg. This strengthens that the moderately broad Fe line could originate from the accretion disc but not too close to the inner stable circular orbit (ISCO), as was found for the O VII soft X-ray emission line (Reeves et al. 2021a). Its origin from the outer accretion disc is also consistent with the timing analysis reported in Lobban et al. (in prep.) where a hint of an extra variability is found at the Fe Kα complex energy range in the fractional variability spectra.","Citation Text":["Reeves et al. 2021a"],"Citation Start End":[[880,899]]} {"Identifier":"2021AandA...654A..89P__Reeves_et_al._2021a_Instance_2","Paragraph":"Therefore, we now fit the two pn spectra between 3 and 10 keV using a power-law model with Galactic absorption, a narrow neutral Fe Kα core (En = 6.4 keV and σn = 0 eV), and a disc line model (RELLINE; Dauser et al. 2010, 2013) to account for the mildly broad line. For the third component, the energy was fixed at 6.4 keV and the spin at zero (since it is not constrained). All parameters of the Fe Kα narrow component and the emissivity index for the mild relativistic Fe K line component were tied between the two epochs. From this modelling (χ2\/d.o.f. = 585.4\/668), we infer an accretion disc emissivity index lower than 2.1 and a disc inclination lower than 24.6°, which is consistent with the inclination angle inferred from the variable O VII soft X-ray emission line (\n\n\n\nθ\n=\n9\n.\n\n9\n\n−\n1.4\n\n\n+\n1.0\n\n\n\n\n$ \\theta=9.9^{+1.0}_{-1.4} $\n\n\n) arising from the accretion disc too (Reeves et al. 2021a). For the narrow core of the Fe Kα line, we measure a EWn ≲ 20 eV, which is in the lower range of the values found for type-1 AGN (∼30−200 eV; Liu & Wang 2010; Shu et al. 2010; Fukazawa et al. 2011; Ricci et al. 2014). This is consistent with the very weak covering factor of 0.06 for the putative torus, which is inferred from the ratio of the infrared to the bolometric luminosity of the source (Ezhikode et al. 2017). Moreover, the torus covering factor measured for Mrk 110 is one of the lowest reported in the Ezhikode et al. (2017) sample; this is also in agreement with the lack of Compton hump. The equivalent widths of the moderately broad Fe Kα line are EWb = 61\n\n\n\n\n\n−\n27\n\n\n+\n23\n\n\n\n$ ^{+23}_{-27} $\n\n\n eV and EWb = 43\n\n\n\n\n\n−\n27\n\n\n+\n22\n\n\n\n$ ^{+22}_{-27} $\n\n\n eV for 2019 and 2020, respectively. Likewise, if we allow the inner disc radius to be free to vary and assume a standard value of three for the disc emissivity index, as well as fixing the inclination angle at 9.9° (χ2\/d.o.f. = 585.1\/668), we infer Rin = 120\n\n\n\n\n\n−\n67\n\n\n+\n263\n\n\n\n$ ^{+263}_{-67} $\n\n\nRg. This strengthens that the moderately broad Fe line could originate from the accretion disc but not too close to the inner stable circular orbit (ISCO), as was found for the O VII soft X-ray emission line (Reeves et al. 2021a). Its origin from the outer accretion disc is also consistent with the timing analysis reported in Lobban et al. (in prep.) where a hint of an extra variability is found at the Fe Kα complex energy range in the fractional variability spectra.","Citation Text":["Reeves et al. 2021a"],"Citation Start End":[[2178,2197]]} {"Identifier":"2022ApJ...940...99H__Zelenyi_et_al._2004_Instance_1","Paragraph":"When B\nX is positive (see the center gray area in Figure 2(a), and corresponding area in Figures 2(e)–(f)), electrons at two energy ranges both present isotropic PAD. As early as 1972, Eastwood et al. (1972) have pointed out that a strong field line curvature would scatter particles. Such a nonadiabatic mechanism has been studied successfully. Büchner and Zelenyi 1989 were the first to use the curvature parameter κ\n2 = R\nmin\/ρ\nmax, the ratio between the minimum curvature radius R\nmin and the maximum particle Larmor radius ρ\nmax, to carry out the trapped particle motion in magnetic field reversals with arbitrary curvature radii in 1989. The parameter depends on the total kinetic energy of the particles and the field geometry, followed by the particle adiabatic invariants. κ ≫ 1 corresponds to the usual adiabatic case. As κ decreases toward unity, the particle motion becomes stochastic due to deterministic chaos. Such behavior, which for κ ≈ 1 becomes strongly chaotic, applies, e.g., to thermal electrons in Earth's magnetotail and makes its collisionless tearing mode instability possible. While for κ 1, it corresponds to the quasi-adiabatic regime, where new current sheet equilibriums can be built (e.g., Zelenyi et al. 2004). We use the curvature radius of magnetic field line R\nC (Figure 2(a)), electron cyclotron radius R\ne (Figure 2(a)) at energy range 6.52–8600 eV separated into two small channels, which is marked by color lines, and the improved adiabatic parameter 1\/κ\n2 = R\ne\/R\nC, the ratio between R\ne and R\nC (Figure 2(c)), to investigate and approve the nonadiabatic motion of electrons (Büchner & Zelenyi 1989; Delcourt et al. 2017). Understandably, R\nC of the magnetic field line in the current sheet is much smaller, showing a strongly curved shape, seen in Figure 2(b). R\ne of electrons is much larger than outside, and the higher-energy range electrons have the larger R\ne, seen in Figure 2(c). Typically, R\ne of electrons and R\nC of the magnetotail field line differ by 3 orders of magnitude (see the red lines in Figures 2(d), 4(d), (i), (m), and (r)). Electrons would be scattered inside the current sheet when the R\ne and R\nC can be compared. Lavraud et al. (2016) have observed a similar pitch-angle scattering process at the magnetopause during a reconnection event, and pointed out that the small curvature radius is the reason by using the κ parameter to analyze first electron MMS data. Thus, when the spacecraft start entering the current sheet, electrons would be scattered along the strongly curved magnetic lines (see the area marked by the first and fourth dotted lines in Figure 2(f)). Meanwhile, high-energy electrons are more easily scattered than low-energy electrons, as electrons at 6.52–35 eV are only scattered at the center of the current sheet (see the area marked by the second and third dotted lines in Figure 2(e)).","Citation Text":["Zelenyi et al. 2004"],"Citation Start End":[[1223,1242]]} {"Identifier":"2021MNRAS.501.4514C___2020_Instance_1","Paragraph":"The electron-positron creation process may induce dynamical instability during the most advanced phases of massive star evolution. Pair creation absorbs part of the thermal energy of the plasma, consequently lowering the thermal pressure. The plasma is not a perfect gas anymore, and temperature variations do not lead to changes in pressure (Kippenhahn, Weigert & Weiss 2012). Regions in which this process happens become locally dynamically unstable. To check if a star is globally stable or not, a perturbation method should be adopted (Ledoux & Walraven 1958). However, Stothers (1999) showed that an evaluation of the first adiabatic exponent properly weighted and integrated over the whole star, 〈Γ1〉, is a very good approximation to determine the dynamical stability of a star. As done by other authors (e.g. Marchant et al. 2019; Farmer et al. 2019, 2020), we adopted the Stothers (1999) stability criterion, which states that a star is stable if\n(4)$$\\begin{eqnarray*}\r\n\\mbox{$\\langle \\Gamma _{1} \\rangle _{\\rm }$} = \\frac{\\int ^{M}_0 \\frac{\\Gamma _1 P}{\\rho } dm}{\\int ^{M}_0 \\frac{P}{\\rho } dm} \\gt \\frac{4}{3},\r\n\\end{eqnarray*}$$where Γ1 is the first adiabatic exponent, P is the pressure, ρ is the density and dm is the element of mass. We decided to compute the above integrals in two ways. In the first case, the integral is calculated from the centre of the star (M = 0) up to the mass of helium core (M = MHe), defining 〈Γ1〉Core; in the second case, we compute the integral from the centre to the surface of the star (M = MTOT), to include the contribution of the envelope, thus 〈Γ1〉TOT. These two values are computed at each time-step for all tracks. In the case of pure-He stars, 〈Γ1〉Core = 〈Γ1〉TOT. Since parsec is a hydro-static code, we cannot follow the evolution through the dynamical collapse; we stop the computation if the 〈Γ1〉 4\/3 + 0.01, to be conservative, and label the star as a PI. Since we cannot follow the hydrodynamical evolution, we cannot distinguish between PPI and PISN: we classify both of them as PI and we assume that both of them leave no compact object. This makes our results for the BH mass even more conservative, because stars that undergo a PPI might still retain most of their mass after weak pulses and form a massive BH by core collapse ( Farmer et al. 2019; Marchant et al. 2019).","Citation Text":["Farmer et al.","2020"],"Citation Start End":[[838,851],[858,862]]} {"Identifier":"2022AandA...664A.161B__Thiabaud_et_al._2015b_Instance_1","Paragraph":"In regions of high C\/O, planets form primarily from carbonates, and in regions of low C\/O, the Mg\/Si determines the types of silicates that dominate the compositions (e.g., Brewer et al. 2016, and references therein). This means that the C\/O ratio controls the distribution of Si among carbide and oxide species. If C\/O is greater than 0.8, Si exists in solid form primarily as SiC, and also graphite and TiC will be formed; for C\/O ratios below 0.8, Si is present in rock-forming minerals as ${\\rm{SiO}}_4^{4 - }$SiO44− or SiO2, serving as seeds for Mg silicates for which the exact composition will be controlled by the Mg\/Si value (Bond et al. 2010; Thiabaud et al. 2015b). Moreover, Thiabaud et al. (2015a) have shown that the condensation of volatile species as a function of radial distance allows for C\/O enrichment in specific parts of the protoplanetary disk of up to four times the solar values, leading to the formation of planets that can be enriched in C\/O in their envelope up to three times the solar value. This is the case of HD209458b observed by Giacobbe et al. (2021) for which a scenario of planet formation beyond the water snowline and migration toward its host star through disk or disk-free migration was hypothesized (see also Brewer et al. 2017). At the same time, Mg\/Si governs the distribution of silicates: for Mg\/Si 1, Mg forms orthopyroxene (MgSiO3) and the excess Si is present as other silicate species such as feldspars (CaAl2Si2O8, NaAlSiO8) or olivine (Mg2SiO4); for Mg\/Si values ranging from 1 to 2, Mg is distributed between olivine and pyroxene; for Mg\/Si > 2, all available Si is consumed to form olivine with excess Mg available to bond with other minerals, mostly oxides such as MgO or MgS (Bond et al. 2010; Thiabaud et al. 2015b). The peak of the Mg\/Si-C\/O distribution for our targets is therefore consistent with Si which will take solid form as ${\\rm{SiO}}_4^{4 - }$SiO44− and SiO2 and Mg equally distributed between pyroxene and olivine.","Citation Text":["Thiabaud et al. 2015b"],"Citation Start End":[[653,674]]} {"Identifier":"2022AandA...664A.161B__Thiabaud_et_al._2015b_Instance_2","Paragraph":"In regions of high C\/O, planets form primarily from carbonates, and in regions of low C\/O, the Mg\/Si determines the types of silicates that dominate the compositions (e.g., Brewer et al. 2016, and references therein). This means that the C\/O ratio controls the distribution of Si among carbide and oxide species. If C\/O is greater than 0.8, Si exists in solid form primarily as SiC, and also graphite and TiC will be formed; for C\/O ratios below 0.8, Si is present in rock-forming minerals as ${\\rm{SiO}}_4^{4 - }$SiO44− or SiO2, serving as seeds for Mg silicates for which the exact composition will be controlled by the Mg\/Si value (Bond et al. 2010; Thiabaud et al. 2015b). Moreover, Thiabaud et al. (2015a) have shown that the condensation of volatile species as a function of radial distance allows for C\/O enrichment in specific parts of the protoplanetary disk of up to four times the solar values, leading to the formation of planets that can be enriched in C\/O in their envelope up to three times the solar value. This is the case of HD209458b observed by Giacobbe et al. (2021) for which a scenario of planet formation beyond the water snowline and migration toward its host star through disk or disk-free migration was hypothesized (see also Brewer et al. 2017). At the same time, Mg\/Si governs the distribution of silicates: for Mg\/Si 1, Mg forms orthopyroxene (MgSiO3) and the excess Si is present as other silicate species such as feldspars (CaAl2Si2O8, NaAlSiO8) or olivine (Mg2SiO4); for Mg\/Si values ranging from 1 to 2, Mg is distributed between olivine and pyroxene; for Mg\/Si > 2, all available Si is consumed to form olivine with excess Mg available to bond with other minerals, mostly oxides such as MgO or MgS (Bond et al. 2010; Thiabaud et al. 2015b). The peak of the Mg\/Si-C\/O distribution for our targets is therefore consistent with Si which will take solid form as ${\\rm{SiO}}_4^{4 - }$SiO44− and SiO2 and Mg equally distributed between pyroxene and olivine.","Citation Text":["Thiabaud et al. 2015b"],"Citation Start End":[[1753,1774]]} {"Identifier":"2022MNRAS.510.3876L__Ellerbroek_&_Andersen_2008_Instance_1","Paragraph":"Adaptive optics (AO; Beckers 1993) has become a key technology for all the main existing telescopes and is considered an enabling technology for future Extremely Large Telescopes (ELTs; Ramsay et al. 2016; Boyer 2018; Bouchez et al. 2018). AO requires sufficiently bright reference sources for the measurement of the wavefront (WF) distortions introduced by the atmospheric turbulence: Sodium laser guide stars (LGS; Foy & Labeyrie 1985; Tallon & Foy 1990) are currently the only valid option to increase the low sky coverage allowed by the use of natural stars (Ellerbroek & Andersen 2008). A Sodium LGS is generated by a laser beam at 589 nm wavelength that excites the Sodium atoms concentrated in a ∼13 km thick layer at about 90 km above the ground (Pfrommer & Hickson 2014), returning a photon flux at the same wavelength (Happer et al. 1994; Thomas et al. 2008). The Sodium layer vertical extension and its variable density profile (Pfrommer, Hickson & She 2009; Holzlöhner et al. 2016) lead to some peculiar complications of the WF sensing process (Lombini 2011). The Shack–Hartmann WF Sensor (SHWS) is the current baseline for the LGS WF sensors (WSs) for the future ELT AO instruments (Boyer & Ellerbroek 2016; Stuik et al. 2016; Males et al. 2018; Sauvage et al. 2018). The LGS spots appear elongated in the sub-apertures located off-axis with respect to the upward laser beam, due to the parallactic effect; the elongation points at the laser launch location and its amplitude increases with the distance from the launcher itself (Fig. 1). The LGS angular elongation ϵ can be approximated by\n(1)$$\\begin{eqnarray}\r\n\\epsilon \\approx r \\frac{\\Delta H}{H^2} \\text{cos}(\\xi) ,\r\n\\end{eqnarray}$$where r is the sub-aperture distance from the launcher, H is the Sodium layer mean altitude, ΔH is the layer vertical extension, and ξ is the Zenith angle. The spot position angle ω is\n(2)$$\\begin{eqnarray}\r\n\\omega = \\text{atan}\\left(\\frac{y_l-y_{s}}{x_l - x_{s}}\\right) ,\r\n\\end{eqnarray}$$","Citation Text":["Ellerbroek & Andersen 2008"],"Citation Start End":[[563,589]]} {"Identifier":"2022MNRAS.510.3876LBouchez_et_al._2018_Instance_1","Paragraph":"Adaptive optics (AO; Beckers 1993) has become a key technology for all the main existing telescopes and is considered an enabling technology for future Extremely Large Telescopes (ELTs; Ramsay et al. 2016; Boyer 2018; Bouchez et al. 2018). AO requires sufficiently bright reference sources for the measurement of the wavefront (WF) distortions introduced by the atmospheric turbulence: Sodium laser guide stars (LGS; Foy & Labeyrie 1985; Tallon & Foy 1990) are currently the only valid option to increase the low sky coverage allowed by the use of natural stars (Ellerbroek & Andersen 2008). A Sodium LGS is generated by a laser beam at 589 nm wavelength that excites the Sodium atoms concentrated in a ∼13 km thick layer at about 90 km above the ground (Pfrommer & Hickson 2014), returning a photon flux at the same wavelength (Happer et al. 1994; Thomas et al. 2008). The Sodium layer vertical extension and its variable density profile (Pfrommer, Hickson & She 2009; Holzlöhner et al. 2016) lead to some peculiar complications of the WF sensing process (Lombini 2011). The Shack–Hartmann WF Sensor (SHWS) is the current baseline for the LGS WF sensors (WSs) for the future ELT AO instruments (Boyer & Ellerbroek 2016; Stuik et al. 2016; Males et al. 2018; Sauvage et al. 2018). The LGS spots appear elongated in the sub-apertures located off-axis with respect to the upward laser beam, due to the parallactic effect; the elongation points at the laser launch location and its amplitude increases with the distance from the launcher itself (Fig. 1). The LGS angular elongation ϵ can be approximated by\n(1)$$\\begin{eqnarray}\r\n\\epsilon \\approx r \\frac{\\Delta H}{H^2} \\text{cos}(\\xi) ,\r\n\\end{eqnarray}$$where r is the sub-aperture distance from the launcher, H is the Sodium layer mean altitude, ΔH is the layer vertical extension, and ξ is the Zenith angle. The spot position angle ω is\n(2)$$\\begin{eqnarray}\r\n\\omega = \\text{atan}\\left(\\frac{y_l-y_{s}}{x_l - x_{s}}\\right) ,\r\n\\end{eqnarray}$$","Citation Text":["Bouchez et al. 2018"],"Citation Start End":[[218,237]]} {"Identifier":"2022MNRAS.510.3876LPfrommer_&_Hickson_2014_Instance_1","Paragraph":"Adaptive optics (AO; Beckers 1993) has become a key technology for all the main existing telescopes and is considered an enabling technology for future Extremely Large Telescopes (ELTs; Ramsay et al. 2016; Boyer 2018; Bouchez et al. 2018). AO requires sufficiently bright reference sources for the measurement of the wavefront (WF) distortions introduced by the atmospheric turbulence: Sodium laser guide stars (LGS; Foy & Labeyrie 1985; Tallon & Foy 1990) are currently the only valid option to increase the low sky coverage allowed by the use of natural stars (Ellerbroek & Andersen 2008). A Sodium LGS is generated by a laser beam at 589 nm wavelength that excites the Sodium atoms concentrated in a ∼13 km thick layer at about 90 km above the ground (Pfrommer & Hickson 2014), returning a photon flux at the same wavelength (Happer et al. 1994; Thomas et al. 2008). The Sodium layer vertical extension and its variable density profile (Pfrommer, Hickson & She 2009; Holzlöhner et al. 2016) lead to some peculiar complications of the WF sensing process (Lombini 2011). The Shack–Hartmann WF Sensor (SHWS) is the current baseline for the LGS WF sensors (WSs) for the future ELT AO instruments (Boyer & Ellerbroek 2016; Stuik et al. 2016; Males et al. 2018; Sauvage et al. 2018). The LGS spots appear elongated in the sub-apertures located off-axis with respect to the upward laser beam, due to the parallactic effect; the elongation points at the laser launch location and its amplitude increases with the distance from the launcher itself (Fig. 1). The LGS angular elongation ϵ can be approximated by\n(1)$$\\begin{eqnarray}\r\n\\epsilon \\approx r \\frac{\\Delta H}{H^2} \\text{cos}(\\xi) ,\r\n\\end{eqnarray}$$where r is the sub-aperture distance from the launcher, H is the Sodium layer mean altitude, ΔH is the layer vertical extension, and ξ is the Zenith angle. The spot position angle ω is\n(2)$$\\begin{eqnarray}\r\n\\omega = \\text{atan}\\left(\\frac{y_l-y_{s}}{x_l - x_{s}}\\right) ,\r\n\\end{eqnarray}$$","Citation Text":["Pfrommer & Hickson 2014"],"Citation Start End":[[755,778]]} {"Identifier":"2022MNRAS.510.3876LStuik_et_al._2016_Instance_1","Paragraph":"Adaptive optics (AO; Beckers 1993) has become a key technology for all the main existing telescopes and is considered an enabling technology for future Extremely Large Telescopes (ELTs; Ramsay et al. 2016; Boyer 2018; Bouchez et al. 2018). AO requires sufficiently bright reference sources for the measurement of the wavefront (WF) distortions introduced by the atmospheric turbulence: Sodium laser guide stars (LGS; Foy & Labeyrie 1985; Tallon & Foy 1990) are currently the only valid option to increase the low sky coverage allowed by the use of natural stars (Ellerbroek & Andersen 2008). A Sodium LGS is generated by a laser beam at 589 nm wavelength that excites the Sodium atoms concentrated in a ∼13 km thick layer at about 90 km above the ground (Pfrommer & Hickson 2014), returning a photon flux at the same wavelength (Happer et al. 1994; Thomas et al. 2008). The Sodium layer vertical extension and its variable density profile (Pfrommer, Hickson & She 2009; Holzlöhner et al. 2016) lead to some peculiar complications of the WF sensing process (Lombini 2011). The Shack–Hartmann WF Sensor (SHWS) is the current baseline for the LGS WF sensors (WSs) for the future ELT AO instruments (Boyer & Ellerbroek 2016; Stuik et al. 2016; Males et al. 2018; Sauvage et al. 2018). The LGS spots appear elongated in the sub-apertures located off-axis with respect to the upward laser beam, due to the parallactic effect; the elongation points at the laser launch location and its amplitude increases with the distance from the launcher itself (Fig. 1). The LGS angular elongation ϵ can be approximated by\n(1)$$\\begin{eqnarray}\r\n\\epsilon \\approx r \\frac{\\Delta H}{H^2} \\text{cos}(\\xi) ,\r\n\\end{eqnarray}$$where r is the sub-aperture distance from the launcher, H is the Sodium layer mean altitude, ΔH is the layer vertical extension, and ξ is the Zenith angle. The spot position angle ω is\n(2)$$\\begin{eqnarray}\r\n\\omega = \\text{atan}\\left(\\frac{y_l-y_{s}}{x_l - x_{s}}\\right) ,\r\n\\end{eqnarray}$$","Citation Text":["Stuik et al. 2016"],"Citation Start End":[[1222,1239]]} {"Identifier":"2016ApJ...832...27A__Emslie_et_al._2012_Instance_1","Paragraph":"The energy partition study of Emslie et al. (2012) was restricted to 38 large solar eruptive events. In a more comprehensive study of the global flare energetics we choose a data set that contains the 400 largest (GOES M- and X-class) flare events observed during the first 3.5 years of the SDO era. Previously, we determined the dissipated magnetic energies Emag in these flares based on fitting the vertical-current approximation of a nonlinear force-free field (NLFFF) solution to the loop geometries detected in EUV images from SDO\/AIA, a new method that could be applied to 177 events with a heliographic longitude of \n\n\n\n\n\n (Paper I). We also determined the thermal energy Eth in the soft X-ray and EUV-emitting plasma during the flare peak times based on a multi-temperature DEM forward-fitting method to SDO\/AIA image pixels with spatial synthesis, which was applicable to 391 events (Paper II). In the present study, we determined the nonthermal energy Ent contained in accelerated electrons based on spectral fits to RHESSI data using the OSPEX software, which was applicable to 191 events. The major conclusions of the new results emerging from this study are as follows.\n\n1.\nThe (logarithmic) mean energy ratio of the nonthermal energy to the total magnetically dissipated flare energy is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n, which yields an uncertainty of \n\n\n\n\n\n for the mean, i.e., \n\n\n\n\n\n. The majority (\n\n\n\n\n\n) of the flare events fulfill the inequality \n\n\n\n\n\n, which suggests that magnetic energy dissipation (most likely by a magnetic reconnection process) provides sufficient energy to accelerate the nonthermal electrons detected by bremsstrahlung in hard X-rays. Our results yield an order of magnitude higher electron acceleration efficiency than previous estimates, i.e., \n\n\n\n\n\n (with N = 37, Emslie et al. 2012).\n\n\n2.\nThe (logarithmic) mean of the thermal energy Eth to the nonthermal energy Ent is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n. The fraction of flares with thermal energy smaller than the nonthermal energy, as expected in the thick-target model, is found to be the case for \n\n\n\n\n\n only. Therefore, the thick-target model is sufficient to explain the full amount of thermal energy in most flares, in the framework of the warm-target model. The cross-over method shows the opposite tendency, but we suspect that the cross-over method overestimates the low-energy cutoff and underestimates the nonthermal energies. Previous estimates yielded a similar ratio, i.e., \n\n\n\n\n\n (Emslie et al. 2012).\n\n\n3.\nA corollary of the two previous conclusions is that the thermal to magnetic energy ratio is \n\n\n\n\n\n. A total of 95% of flares fulfills the inequality \n\n\n\n\n\n, indicating that all thermal energy in flares is supplied by magnetic energy. Previous estimates were a factor of 17 lower, i.e., \n\n\n\n\n\n (Emslie et al. 2012), which would imply a very inefficient magnetic to thermal energy conversion process.\n\n\n4.\nThe largest uncertainty in the calculation of nonthermal energies, the low-energy cutoff, is found to yield different values for two used methods, i.e., \n\n\n\n\n\n keV for the warm thick-target model, versus \n\n\n\n\n\n for the thermal\/nonthermal cross-over method. The calculation of the nonthermal energies is highly sensitive to the value of the low-energy cutoff, which strongly depends on the assumed (warm-target) temperature.\n\n\n5.\nThe flare temperature can be characterized with three different definitions, for which we found the following (67%-standard deviation) ranges: \n\n\n\n\n\n MK for the AIA DEM peak temperature, \n\n\n\n\n\n MK for the emission measure-weighted temperatures, and \n\n\n\n\n\n MK for the RHESSI high-temperature DEM tails. The median ratios are found to be \n\n\n\n\n\n and \n\n\n\n\n\n. The mean active region temperature evaluated from DEMs with AIA, Te = 8.6 MK, is used to estimate the low-energy cutoff ec of the nonthermal component according to the warm-target model, i.e., \n\n\n\n\n\n. The low-energy cutoff ec of the nonthermal spectrum has a strong functional dependence on the temperature TR.\n\n\n","Citation Text":["Emslie et al. (2012)"],"Citation Start End":[[30,50]]} {"Identifier":"2016ApJ...832...27A__Emslie_et_al._2012_Instance_2","Paragraph":"The energy partition study of Emslie et al. (2012) was restricted to 38 large solar eruptive events. In a more comprehensive study of the global flare energetics we choose a data set that contains the 400 largest (GOES M- and X-class) flare events observed during the first 3.5 years of the SDO era. Previously, we determined the dissipated magnetic energies Emag in these flares based on fitting the vertical-current approximation of a nonlinear force-free field (NLFFF) solution to the loop geometries detected in EUV images from SDO\/AIA, a new method that could be applied to 177 events with a heliographic longitude of \n\n\n\n\n\n (Paper I). We also determined the thermal energy Eth in the soft X-ray and EUV-emitting plasma during the flare peak times based on a multi-temperature DEM forward-fitting method to SDO\/AIA image pixels with spatial synthesis, which was applicable to 391 events (Paper II). In the present study, we determined the nonthermal energy Ent contained in accelerated electrons based on spectral fits to RHESSI data using the OSPEX software, which was applicable to 191 events. The major conclusions of the new results emerging from this study are as follows.\n\n1.\nThe (logarithmic) mean energy ratio of the nonthermal energy to the total magnetically dissipated flare energy is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n, which yields an uncertainty of \n\n\n\n\n\n for the mean, i.e., \n\n\n\n\n\n. The majority (\n\n\n\n\n\n) of the flare events fulfill the inequality \n\n\n\n\n\n, which suggests that magnetic energy dissipation (most likely by a magnetic reconnection process) provides sufficient energy to accelerate the nonthermal electrons detected by bremsstrahlung in hard X-rays. Our results yield an order of magnitude higher electron acceleration efficiency than previous estimates, i.e., \n\n\n\n\n\n (with N = 37, Emslie et al. 2012).\n\n\n2.\nThe (logarithmic) mean of the thermal energy Eth to the nonthermal energy Ent is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n. The fraction of flares with thermal energy smaller than the nonthermal energy, as expected in the thick-target model, is found to be the case for \n\n\n\n\n\n only. Therefore, the thick-target model is sufficient to explain the full amount of thermal energy in most flares, in the framework of the warm-target model. The cross-over method shows the opposite tendency, but we suspect that the cross-over method overestimates the low-energy cutoff and underestimates the nonthermal energies. Previous estimates yielded a similar ratio, i.e., \n\n\n\n\n\n (Emslie et al. 2012).\n\n\n3.\nA corollary of the two previous conclusions is that the thermal to magnetic energy ratio is \n\n\n\n\n\n. A total of 95% of flares fulfills the inequality \n\n\n\n\n\n, indicating that all thermal energy in flares is supplied by magnetic energy. Previous estimates were a factor of 17 lower, i.e., \n\n\n\n\n\n (Emslie et al. 2012), which would imply a very inefficient magnetic to thermal energy conversion process.\n\n\n4.\nThe largest uncertainty in the calculation of nonthermal energies, the low-energy cutoff, is found to yield different values for two used methods, i.e., \n\n\n\n\n\n keV for the warm thick-target model, versus \n\n\n\n\n\n for the thermal\/nonthermal cross-over method. The calculation of the nonthermal energies is highly sensitive to the value of the low-energy cutoff, which strongly depends on the assumed (warm-target) temperature.\n\n\n5.\nThe flare temperature can be characterized with three different definitions, for which we found the following (67%-standard deviation) ranges: \n\n\n\n\n\n MK for the AIA DEM peak temperature, \n\n\n\n\n\n MK for the emission measure-weighted temperatures, and \n\n\n\n\n\n MK for the RHESSI high-temperature DEM tails. The median ratios are found to be \n\n\n\n\n\n and \n\n\n\n\n\n. The mean active region temperature evaluated from DEMs with AIA, Te = 8.6 MK, is used to estimate the low-energy cutoff ec of the nonthermal component according to the warm-target model, i.e., \n\n\n\n\n\n. The low-energy cutoff ec of the nonthermal spectrum has a strong functional dependence on the temperature TR.\n\n\n","Citation Text":["Emslie et al. 2012"],"Citation Start End":[[1873,1891]]} {"Identifier":"2016ApJ...832...27A__Emslie_et_al._2012_Instance_3","Paragraph":"The energy partition study of Emslie et al. (2012) was restricted to 38 large solar eruptive events. In a more comprehensive study of the global flare energetics we choose a data set that contains the 400 largest (GOES M- and X-class) flare events observed during the first 3.5 years of the SDO era. Previously, we determined the dissipated magnetic energies Emag in these flares based on fitting the vertical-current approximation of a nonlinear force-free field (NLFFF) solution to the loop geometries detected in EUV images from SDO\/AIA, a new method that could be applied to 177 events with a heliographic longitude of \n\n\n\n\n\n (Paper I). We also determined the thermal energy Eth in the soft X-ray and EUV-emitting plasma during the flare peak times based on a multi-temperature DEM forward-fitting method to SDO\/AIA image pixels with spatial synthesis, which was applicable to 391 events (Paper II). In the present study, we determined the nonthermal energy Ent contained in accelerated electrons based on spectral fits to RHESSI data using the OSPEX software, which was applicable to 191 events. The major conclusions of the new results emerging from this study are as follows.\n\n1.\nThe (logarithmic) mean energy ratio of the nonthermal energy to the total magnetically dissipated flare energy is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n, which yields an uncertainty of \n\n\n\n\n\n for the mean, i.e., \n\n\n\n\n\n. The majority (\n\n\n\n\n\n) of the flare events fulfill the inequality \n\n\n\n\n\n, which suggests that magnetic energy dissipation (most likely by a magnetic reconnection process) provides sufficient energy to accelerate the nonthermal electrons detected by bremsstrahlung in hard X-rays. Our results yield an order of magnitude higher electron acceleration efficiency than previous estimates, i.e., \n\n\n\n\n\n (with N = 37, Emslie et al. 2012).\n\n\n2.\nThe (logarithmic) mean of the thermal energy Eth to the nonthermal energy Ent is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n. The fraction of flares with thermal energy smaller than the nonthermal energy, as expected in the thick-target model, is found to be the case for \n\n\n\n\n\n only. Therefore, the thick-target model is sufficient to explain the full amount of thermal energy in most flares, in the framework of the warm-target model. The cross-over method shows the opposite tendency, but we suspect that the cross-over method overestimates the low-energy cutoff and underestimates the nonthermal energies. Previous estimates yielded a similar ratio, i.e., \n\n\n\n\n\n (Emslie et al. 2012).\n\n\n3.\nA corollary of the two previous conclusions is that the thermal to magnetic energy ratio is \n\n\n\n\n\n. A total of 95% of flares fulfills the inequality \n\n\n\n\n\n, indicating that all thermal energy in flares is supplied by magnetic energy. Previous estimates were a factor of 17 lower, i.e., \n\n\n\n\n\n (Emslie et al. 2012), which would imply a very inefficient magnetic to thermal energy conversion process.\n\n\n4.\nThe largest uncertainty in the calculation of nonthermal energies, the low-energy cutoff, is found to yield different values for two used methods, i.e., \n\n\n\n\n\n keV for the warm thick-target model, versus \n\n\n\n\n\n for the thermal\/nonthermal cross-over method. The calculation of the nonthermal energies is highly sensitive to the value of the low-energy cutoff, which strongly depends on the assumed (warm-target) temperature.\n\n\n5.\nThe flare temperature can be characterized with three different definitions, for which we found the following (67%-standard deviation) ranges: \n\n\n\n\n\n MK for the AIA DEM peak temperature, \n\n\n\n\n\n MK for the emission measure-weighted temperatures, and \n\n\n\n\n\n MK for the RHESSI high-temperature DEM tails. The median ratios are found to be \n\n\n\n\n\n and \n\n\n\n\n\n. The mean active region temperature evaluated from DEMs with AIA, Te = 8.6 MK, is used to estimate the low-energy cutoff ec of the nonthermal component according to the warm-target model, i.e., \n\n\n\n\n\n. The low-energy cutoff ec of the nonthermal spectrum has a strong functional dependence on the temperature TR.\n\n\n","Citation Text":["Emslie et al. 2012"],"Citation Start End":[[2617,2635]]} {"Identifier":"2016ApJ...832...27A__Emslie_et_al._2012_Instance_4","Paragraph":"The energy partition study of Emslie et al. (2012) was restricted to 38 large solar eruptive events. In a more comprehensive study of the global flare energetics we choose a data set that contains the 400 largest (GOES M- and X-class) flare events observed during the first 3.5 years of the SDO era. Previously, we determined the dissipated magnetic energies Emag in these flares based on fitting the vertical-current approximation of a nonlinear force-free field (NLFFF) solution to the loop geometries detected in EUV images from SDO\/AIA, a new method that could be applied to 177 events with a heliographic longitude of \n\n\n\n\n\n (Paper I). We also determined the thermal energy Eth in the soft X-ray and EUV-emitting plasma during the flare peak times based on a multi-temperature DEM forward-fitting method to SDO\/AIA image pixels with spatial synthesis, which was applicable to 391 events (Paper II). In the present study, we determined the nonthermal energy Ent contained in accelerated electrons based on spectral fits to RHESSI data using the OSPEX software, which was applicable to 191 events. The major conclusions of the new results emerging from this study are as follows.\n\n1.\nThe (logarithmic) mean energy ratio of the nonthermal energy to the total magnetically dissipated flare energy is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n, which yields an uncertainty of \n\n\n\n\n\n for the mean, i.e., \n\n\n\n\n\n. The majority (\n\n\n\n\n\n) of the flare events fulfill the inequality \n\n\n\n\n\n, which suggests that magnetic energy dissipation (most likely by a magnetic reconnection process) provides sufficient energy to accelerate the nonthermal electrons detected by bremsstrahlung in hard X-rays. Our results yield an order of magnitude higher electron acceleration efficiency than previous estimates, i.e., \n\n\n\n\n\n (with N = 37, Emslie et al. 2012).\n\n\n2.\nThe (logarithmic) mean of the thermal energy Eth to the nonthermal energy Ent is found to be \n\n\n\n\n\n, with a logarithmic standard deviation corresponding to a factor of \n\n\n\n\n\n. The fraction of flares with thermal energy smaller than the nonthermal energy, as expected in the thick-target model, is found to be the case for \n\n\n\n\n\n only. Therefore, the thick-target model is sufficient to explain the full amount of thermal energy in most flares, in the framework of the warm-target model. The cross-over method shows the opposite tendency, but we suspect that the cross-over method overestimates the low-energy cutoff and underestimates the nonthermal energies. Previous estimates yielded a similar ratio, i.e., \n\n\n\n\n\n (Emslie et al. 2012).\n\n\n3.\nA corollary of the two previous conclusions is that the thermal to magnetic energy ratio is \n\n\n\n\n\n. A total of 95% of flares fulfills the inequality \n\n\n\n\n\n, indicating that all thermal energy in flares is supplied by magnetic energy. Previous estimates were a factor of 17 lower, i.e., \n\n\n\n\n\n (Emslie et al. 2012), which would imply a very inefficient magnetic to thermal energy conversion process.\n\n\n4.\nThe largest uncertainty in the calculation of nonthermal energies, the low-energy cutoff, is found to yield different values for two used methods, i.e., \n\n\n\n\n\n keV for the warm thick-target model, versus \n\n\n\n\n\n for the thermal\/nonthermal cross-over method. The calculation of the nonthermal energies is highly sensitive to the value of the low-energy cutoff, which strongly depends on the assumed (warm-target) temperature.\n\n\n5.\nThe flare temperature can be characterized with three different definitions, for which we found the following (67%-standard deviation) ranges: \n\n\n\n\n\n MK for the AIA DEM peak temperature, \n\n\n\n\n\n MK for the emission measure-weighted temperatures, and \n\n\n\n\n\n MK for the RHESSI high-temperature DEM tails. The median ratios are found to be \n\n\n\n\n\n and \n\n\n\n\n\n. The mean active region temperature evaluated from DEMs with AIA, Te = 8.6 MK, is used to estimate the low-energy cutoff ec of the nonthermal component according to the warm-target model, i.e., \n\n\n\n\n\n. The low-energy cutoff ec of the nonthermal spectrum has a strong functional dependence on the temperature TR.\n\n\n","Citation Text":["Emslie et al. 2012"],"Citation Start End":[[2937,2955]]} {"Identifier":"2020MNRAS.494.2969T__Bardeen_et_al._1986_Instance_1","Paragraph":"Under the symmetry assumption of Friedmann–Lemaître cosmologies, all fluids are characterized by their density and their equation of state. In spatially flat cosmologies with the matter density parameter Ωm and the corresponding dark energy density 1 − Ωm one obtains for the Hubble function $H(a)=\\dot{a}\/a$ the expression,\n(1)$$\\begin{eqnarray*}\r\n\\frac{H^2(a)}{H_0^2} = \\frac{\\Omega _\\mathrm{m}}{a^{3}} + \\frac{1-\\Omega _\\mathrm{m}}{a^{3(1+w)}},\r\n\\end{eqnarray*}$$The comoving distance χ is related to the scale factor a through\n(2)$$\\begin{eqnarray*}\r\n\\chi = -c\\int _1^a\\:\\frac{\\mathrm{d}a}{a^2 H(a)},\r\n\\end{eqnarray*}$$where the Hubble distance χH = c\/H0 sets the distance scale for cosmological distance measures. Small fluctuations δ in the distribution of dark matter grow, as long as they are in the linear regime |δ| ≪ 1, according to the growth function D+(a) (Linder & Jenkins 2003),\n(3)$$\\begin{eqnarray*}\r\n\\frac{\\mathrm{d}^2}{\\mathrm{d}a^2}D_+(a) + \\frac{2-q}{a}\\frac{\\mathrm{d}}{\\mathrm{d}a}D_+(a) - \\frac{3}{2a^2}\\Omega _\\mathrm{m}(a) D_+(a) = 0,\r\n\\end{eqnarray*}$$and their statistics is characterized by the spectrum $\\langle \\delta (\\boldsymbol {k})\\delta ^*(\\boldsymbol {k}^\\prime)\\rangle = (2\\pi)^3\\delta _D(\\boldsymbol {k}-\\boldsymbol {k}^\\prime)P_\\delta (k)$. Inflation generates a spectrum of the form $P_\\delta (k)\\propto k^{n_s}T^2(k)$ with the transfer function T(k) (Bardeen et al. 1986) which is normalized to the variance σ8 smoothed to the scale of 8 Mpc h−1,\n(4)$$\\begin{eqnarray*}\r\n\\sigma _8^2 = \\int _0^\\infty \\frac{k^2\\mathrm{d}k}{2\\pi ^2}\\: W^2(8 \\mathrm{Mpc}\/h\\times k)\\:P_\\delta (k),\r\n\\end{eqnarray*}$$with a Fourier-transformed spherical top-hat W(x) = 3j1(x)\/x as the filter function. From the CDM spectrum of the density perturbation, the spectrum of the dimensionless Newtonian gravitational potential Φ can be obtained,\n(5)$$\\begin{eqnarray*}\r\nP_\\Phi (k) \\propto \\left(\\frac{3\\Omega _\\mathrm{m}}{2 (k\\chi _H)^2}\\right)^2\\:P_\\delta (k),\r\n\\end{eqnarray*}$$by applying the comoving Poisson equation $\\Delta \\Phi = 3\\Omega _\\mathrm{m}\/(2\\chi _H^2)\\delta$ for deriving the gravitational potential Φ (in units of c2) from the density δ. Because our analysis relies on the assumption of Gaussianity, we need to avoid non-linearly evolving scales and will restrict our analysis to large angular and spatial scales, where the cosmic density field can be approximated to follow a linear evolution, conserving the near-Gaussianity of the initial conditions. We increase the variance of the weak lensing signal and of the intrinsic alignment signal of elliptical galaxies on small scales because of non-linear structure formation using the description of Smith et al. (2003) and Casarini et al. (2011, 2012). Consequently, the cross-correlation between weak lensing and elliptical galaxy shapes will likewise have increased variances on small scales. Shapes of spiral galaxies are set by the initial conditions of structure formation; therefore, we did not apply changes to the linear CDM-spectrum P(k).","Citation Text":["Bardeen et al. 1986"],"Citation Start End":[[1394,1413]]} {"Identifier":"2018ApJ...853...67N__Blanton_&_Moustakas_2009_Instance_1","Paragraph":"(3) Extended cold-accretion model. The actual behavior of cold accretion will be more complicated than suggested by the analytical work of Dekel & Birnboim (2006), which investigated the behavior of mean halos under many simplifications. One possibility is that cold-accretion behavior depends upon the environment. Galaxies with the same halo mass may experience different accretion histories depending on whether they reside in highly crowded regions such as proto-galaxy clusters or in sparse regions that will eventually develop into fields or voids. Keres et al. (2005) used detailed numerical simulation to show that the intensity and time variation of cold-mode accretion indeed depends on the galactic environment. According to their results, there is a tendency for cold-mode accretion to persist into lower redshifts in the region of lower galaxy number densities. Keres et al. (2005) stated that this environmental dependence is driven largely by the galaxy mass dependence of the cold–hot accretion fraction, but they also recognized a truly environmental effect that massive galaxies in low-density environments tend to have higher cold-accretion fractions than those in denser regions. Because disk galaxies, especially those with larger stellar masses (\n\n\n\n\n\n), tend to reside in low-density regions such as fields and poor groups (Blanton & Moustakas 2009), this effect may be important in modeling the evolution of such galaxies. We therefore implement the third type of cold accretion. Because the evaluation of cold accretion by Dekel & Birnboim (2006) is based on many simplified assumptions that make the problem analytically amenable, it is considered that there remains a considerable quantitative ambiguity. In view of this, we take a simple approach in specifying the cosmological history of cold accretion. Specifically, we parameterize the third type of cold accretion using four parameters: the characteristic time, \n\n\n\n\n\n, when cold accretion gives way to hot accretion; the characteristic mass, \n\n\n\n\n\n, which divides hot and cold accretion at \n\n\n\n\n\n; and two parameters, \n\n\n\n\n\n and \n\n\n\n\n\n, that describe the change in the characteristic mass before and after \n\n\n\n\n\n, respectively. In this parameterization, the critical mass is specified as\n18\n\n\n\n\n\n\n\n19\n\n\n\n\n\nIf \n\n\n\n\n\n, the halo gas is assumed to collapse to the disk plane with the freefall time (\n\n\n\n\n\n). Otherwise, the gas is assumed to accrete over the larger of the cooling and freefall times (\n\n\n\n\n\n). This specification, depending on the adopted parameters, accommodates a wide variety of accretion histories. We set \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n throughout this paper. This specification of parameters moves the end of cold accretion to more recent epochs than the prediction of Dekel & Birnboim (2006) for halos with \n\n\n\n\n\n and realizes the prolonged cold accretion suggested in Keres et al. (2005). Under this parameterization, the model gives the best match to the observed disk sizes (Figure 7) and galaxy colors (Figure 9) without changing other observational predictions to a significant degree.","Citation Text":["Blanton & Moustakas 2009"],"Citation Start End":[[1347,1371]]} {"Identifier":"2021MNRAS.502.1136M__Hu_&_Sugiyama_1996_Instance_1","Paragraph":"One of the independent measures to the EM luminosity distance ${\\rm d}_l^{\\rm EM} (z)$ for a metric theory is through its relation with the geometric distance (the angular diameter distance) ${\\rm d}_A(z)= {\\rm d}_l^{\\rm EM}(z)\/(1+z)^2$, according to Etherington’s reciprocity theorem (Etherington 2007) or the distance duality relation. This relation is valid for EM probes if photon number is conserved, and photons propagate along null geodesics. The distance duality relation has been tested from several observations (Holanda, Lima & Ribeiro 2010; Holanda, Gonçalves & Alcaniz 2012; Liao et al. 2016) and will also be tested more stringently in the future (Liao et al. 2016; Arjona et al. 2020; Martinelli et al. 2020; Renzi et al. 2020). The angular diameter distance to any redshift z is related to the BAO scale θBAO in the matter correlation function by (Peebles & Yu 1970; Bond & Efstathiou 1984; Hu & Sugiyama 1996; Eisenstein & Hu 1998, 1997)\n(4)$$\\begin{eqnarray*}\r\n\\theta _{\\rm BAO} (z)= \\frac{r_{\\rm s}}{(1+z){\\rm d}_A(z)},\r\n\\end{eqnarray*}$$where, $r_{\\rm s}= \\int _{z_{\\rm d}}^\\infty {\\rm d}z c_{\\rm s}(z)\/ H(z)$ is the sound horizon where zd denotes the drag redshift. As a result, we can relate the BAO scale with the EM luminosity distance ${\\rm d}_l^{\\rm EM}$ by the relation\n(5)$$\\begin{eqnarray*}\r\n{\\rm d}_l^{\\rm EM} (z)= \\frac{(1+z) r_{\\rm s}}{\\theta _{\\rm BAO}(z)}.\r\n\\end{eqnarray*}$$Using equation (5) in equation (3), we can write\n(6)$$\\begin{eqnarray*}\r\n{\\rm d}^{\\rm GW}_l(z)= \\exp {\\bigg (-\\int {\\rm d}z^{\\prime } \\frac{\\gamma (z^{\\prime })}{1+z^{\\prime }}\\bigg)}\\frac{(1+z) r_{\\rm s}}{\\theta _{\\rm BAO} (z)}.\r\n\\end{eqnarray*}$$This is the key equation of this paper. In this expression, the measurement of the term $\\frac{r_{\\rm s}}{\\theta _{\\rm BAO}(z)}$ comes from EM probes such as large-scale structure galaxy redshift surveys (Eisenstein et al. 2005; Dawson et al. 2013; Alam et al. 2017) and cosmic microwave background (CMB) (Spergel et al. 2003, 2007; Komatsu et al. 2011; Hinshaw et al. 2013; Planck Collaboration XIII 2016; Aghanim et al. 2020), and the measurement of $d_l^{GW}$ arises from the GW strain. We can write the above equation as\n(7)$$\\begin{eqnarray*}\r\n{\\rm d}^{\\rm GW}_l(z)\\theta _{\\rm BAO}(z)= \\exp {\\bigg (-\\int {\\rm d}z^{\\prime } \\frac{\\gamma (z^{\\prime })}{1+z^{\\prime }}\\bigg)}(1+z) r_{\\rm s}.\r\n\\end{eqnarray*}$$This relation shows that the product of the BAO angular scale θBAO(z) and the luminosity distance ${\\rm d}^{\\rm GW}_l(z)$ can measure the frictional term γ(z) as a function of redshift. So, the concordance between the EM geometric probes and the GW luminosity probes allows a way to test the theory of gravity. If the general theory of relativity is the correct theory of gravity, then the product between θBAO(z) and ${\\rm d}^{\\rm GW}_l(z)$ should vary with redshift as (1 + z). Any deviation from this scaling can be a signature of alternative theories of gravity. The quantities θBAO and ${\\rm d}_l^{\\rm GW}$ are measured from large-scale structure and GW data, and the value of rs depends on recombination physics and the sound speed in the baryon–photon fluid at the time of decoupling at redshift z ≈ 1100 (Silk 1968; Peebles & Yu 1970; Sunyaev & Zeldovich 1970; Hu, Sugiyama & Silk 1997). As a result, this relation is nearly model-independent, and can be written directly in terms of observables such as ${\\rm d}_l^{\\rm GW}(z)$, and θBAO(z).","Citation Text":["Hu & Sugiyama 1996"],"Citation Start End":[[907,925]]} {"Identifier":"2016AandA...592L..11S__Bizzocchi_et_al._(2014)_Instance_1","Paragraph":"Figure 3 shows the column densities of H2, c-C3H2 and CH3OH extracted along the dotted line present in Fig. 1, as well as the N(H2) calculated with the model of L1544 described in Keto & Caselli (2010) assuming a beam size of 40′′. The column densities of c-C3H2 and CH3OH were calculated assuming that the lines are optically thin, using the formula given in Eq. (1) of Spezzano et al. (2016). We assumed a Tex of 6 K for c-C3H2 and 6.5 K for CH3OH, as done in Spezzano et al. (2013) and Bizzocchi et al. (2014), respectively. The same works reported that both lines present moderate optical depths (τ 0.4). This plot shows that the decrease of N(H2) towards the south-west, where cyclopropenylidene is more abundant, is much steeper than towards the north-east, where methanol is more abundant. A full map of the N(c-C3H2)\/N(CH3OH) column density ratio can be seen in Fig. A.1, showing a clear peak towards the south-east side of L1544. Figure 3 also shows that c-C3H2 and CH3OH both belong to the same dense core (identified by the brightest peak in N(H2)), but trace different parts of it. We obtain the same result by comparing the line-width and velocity maps of the two molecules, see Fig. B.1. Despite the different spatial distributions, the two molecules trace the same kinematic patterns (velocity gradient and amount of non-thermal motions). This indicates that the velocity fields are dominated by the bulk motions (gravitational contraction and rotation) of the prestellar core, which similarly affect the two sides of the core and do not depend on the chemical composition of the gas. In summary, c-C3H2 and CH3OH trace different parts of the same dense core and no velocity shift is present (unlike for the L1551 case; Swift et al. 2006). We note that the observed transitions of c-C3H2 and CH3OH have relatively high critical densities (between a few ×104 and 106 cm-3), so that these lines are not expected to trace the more diffuse filamentary material surrounding the prestellar core. ","Citation Text":["Bizzocchi et al. (2014)"],"Citation Start End":[[489,512]]} {"Identifier":"2018ApJ...856L...3H__Dragomir_et_al._2015_Instance_1","Paragraph":"Figure 1 shows a schematic of the Planetary Haze Research (PHAZER) experimental setup at Johns Hopkins University (He et al. 2017; Hörst et al. 2018). The initial gas mixtures for our experiments are calculated from the chemical-equilibrium models of Moses et al. (2013), who examined the possible thermochemistry and photochemistry in the atmospheres of Neptune-sized and sub-Neptune-sized exoplanets. Most of the known super-Earth and mini-Neptune size planets known to date were discovered by the Kepler mission (Borucki et al. 2011; Fressin et al. 2013). However, follow-up of Kepler targets to determine planetary mass and atmospheric characterization has been limited due to the brightness of their host stars. The TESS mission (Ricker et al. 2014) will target stars that are 10–100 times brighter than those targeted with the Kepler mission and yield a large sample of super-Earth and mini-Neptune class planets with equilibrium temperatures (Teq) 1000 K (Sullivan et al. 2015). This planetary size (Rp 4 REarth) and temperature (Teq 1000 K) phase space has been recently explored by exoplanet atmospheric characterization efforts for a handful of planets such as GJ 1214b, HD 97658b, GJ 436b, and GJ 3470b, which all indicate that aerosols are shaping the planetary spectrum (e.g., Knutson et al. 2014a, 2014b; Kreidberg et al. 2014; Dragomir et al. 2015). Theoretical studies predict a diverse range of possibilities for the composition of atmospheric envelopes of mini-Neptunes and super-Earths (e.g., Fortney et al. 2013; Howe & Burrows 2015; Wolfgang & Lopez 2015). Broadly speaking, we expect that our hydrogen-rich gas mixtures are more relevant to larger mini-Neptune class planets and carbon dioxide-rich gas mixtures are more relevant to smaller super-Earth class planets, with water-rich gas mixtures being relevant to both classes of planets. However, further observational, theoretical, and laboratory work will be required to confirm or refute the potential diversity in atmospheric compositions for these classes of planets that do not exist in our solar system. The equilibrium calculations relevant to this investigation were performed at conditions of 300, 400, and 600 K at 1 mbar for 100×, 1000×, and 10,000× solar metallicity. Smaller planets are less efficient at accreting the H- and He-rich gas from the protoplanetary disk, and the lighter elements have a greater chance of escaping from smaller planets, which enhances the overall metallicity of planets that are Neptune-sized and smaller. As an example, the O\/H metallicity on Uranus and Neptune is estimated to be 160 and 540 times solar, respectively (Cavalié et al. 2017). Various evolutionary processes could drive the relative abundances of the heavy elements away from solar, but these high-metallicity chemical-equilibrium models provide a reasonable starting point for our study. As listed in Table 1, we included gases with a calculated abundance of 1% or higher to maintain a manageable level of experimental complexity; this resulted in no nitrogen-bearing species in two cases and the exclusion of sulfur-bearing species. Sulfur-bearing species, like H2S, could be important for haze formation (Gao et al. 2017) and will be an avenue of future work. The pressure, temperature, and gas compositions used in the experiments are self-consistent based on the model calculations.","Citation Text":["Dragomir et al. 2015"],"Citation Start End":[[1344,1364]]} {"Identifier":"2018AandA...614A..52B__Fitzgerald_et_al._2007_Instance_1","Paragraph":"Recently, Sezestre et al. (2017) investigated this scenario in a quantitative way, using numerical simulations with test particles. The model is relatively straightforward and makes a minimal number of assumptions. It assumes grains released at a given distance of the star andat several epochs. The dynamical behavior of the grains is ruled by the ratio of the pressure to gravitational forces (β). In the case of AU Mic, the stellar wind exceeds the radiation pressure, so that β scales with the stellar mass loss. The authors considered two situations, one where the source of dust was fixed in the system, and one where it was in Kepleriancircular orbit. To match the positions of the features as well as their projected speeds, the grains must be characterized by high β values of atleast 6, which points to a combination of small grains (a few tenths of m) and large stellar mass loss (a few hundreds of \n\n$\\dot{M_{\\odot}}$\n\n\n\n\n\nM\n⊙\n\n\n.\n\n\n\n), which is in rather good agreement with previous estimations (Fitzgerald et al. 2007; Schüppler et al. 2015). Although several geometries (position of the source, direction of emission, and periodicity) can still match the observations given that only three epochs were available, the fit of the model to the data indicates that the source of this dust production should be located at ~ 8–28 au from the star, that is, within the belt of planetesimals, the “birth ring”. To introduce the aim of this paper, we present in Fig. 1 a sketch of the hypothetical distribution of the features in the system as pictured from the first observations (Boccaletti et al. 2015), and we assume that they originate from an orbiting parent body. An alternative explanation is proposed by Chiang & Fung (2017), in which the fast-moving features would originate from a collisional avalanche site at the intersection of two belts: the main belt, and a belt resulting from the catastrophic disruption of a large asteroid-likebody. Small dust particles would be released from this place and expelled by the stellar wind. This theory involves several assumptions to qualitatively match the observations, but the dynamical behavior of the grains once released is quite similar to the case of a fixed source as proposed in Sezestre et al. (2017). From the photometry of the HST image, Chiang & Fung (2017) roughly estimated that one dust feature should contain ~ 4 ×10−7 M⊕.","Citation Text":["Fitzgerald et al. 2007"],"Citation Start End":[[1010,1032]]} {"Identifier":"2022ApJ...936...95W__Gibson_et_al._2009_Instance_1","Paragraph":"The observed X-ray emission from AGNs may be modified by line-of-sight obscuration, resulting in lower observed X-ray fluxes than those expected from the α\nOX–L\n2500 Å relation. A common approach to parameterize the amount of X-ray weakness uses the Δα\nOX parameter, defined as the difference between the observed α\nOX value and the α\nOX value expected from the α\nOX–L\n2500 Å relation; Δα\nOX = − 0.3838 thus corresponds to a factor of X-ray weakness of 10 at rest-frame 2 keV. Type 2 AGNs are generally X-ray obscured, likely due to the dusty “torus” (e.g., Netzer 2015; Hickox & Alexander 2018). Type 1 AGNs may also have X-ray obscuration from largely dust-free gas.\n13\n\n\n13\nSimilar obscuration from dust-free gas might also be present in some of the type 2 AGNs, though usually not distinguishable from the torus obscuration. For example, broad absorption line (BAL) quasars, which are characterized by blueshifted broad UV absorption lines (e.g., C iv\nλ1549), generally show weak X-ray emission (e.g., Gallagher et al. 2002, 2006; Fan et al. 2009; Gibson et al. 2009). One frequently adopted physical model for BAL quasars is the disk wind model, where the observed BALs originate from an outflowing equatorial wind launched from the accretion disk and radiatively driven by UV-line pressure (e.g., Murray et al. 1995; Proga et al. 2000; Matthews et al. 2016). This model usually invokes “shielding” gas between the wind and nucleus or a clumpy wind (e.g., Baskin et al. 2014; Matthews et al. 2016; Giustini & Proga 2019) to provide obscuration of the nuclear extreme-UV (EUV) and X-ray radiation, which might otherwise overionize the wind and hamper radiative acceleration. BAL quasars are considered generally to have larger inclination angles than non-BAL quasars, with the line of sight to the UV continuum region of the accretion disk intersecting the wind, leading to the observed BALs. The line of sight to the X-ray-emitting corona, though not necessarily the same as the UV line of sight, is likely also through the shielding gas or the clumpy wind, resulting in the often-observed X-ray weakness (e.g., Figure 1 of Luo et al. 2013). Besides BAL quasars, a small fraction (5.8% ± 0.7%) of non-BAL type 1 quasars have been found to be X-ray weak, likely due to absorption (e.g., Pu et al. 2020). They may share a similar nature to the BAL quasars; they do not show any UV BALs, probably due to geometric effects (e.g., small inclination angles) or a low velocity of the wind along the UV line of sight (e.g., Giustini & Proga 2019).","Citation Text":["Gibson et al. 2009"],"Citation Start End":[[1052,1070]]} {"Identifier":"2022MNRAS.511L..35A__Peißker_et_al._2020_Instance_1","Paragraph":"From these two observational campaigns, the inference on the nature of Sgr A* has been reached on the ground of novel theoretical understandings. A recent important result has been obtained in Matsumoto, Chan & Piran (2020) (see also Tursunov et al. 2020), by re-considering the flare emissions around Sgr A*, emphasizing both, that their motion is not purely geodesic, and establishing a limit on the spin of a putative Kerr BH mass of |a| 0.5. Soon after, in Becerra-Vergara et al. (2020), it was introduced an alternative model to the classical BH in Sgr A* by re-interpreting it as a high concentration of quantum self-gravitating DM made of fermions of about 56 keV c−2 rest mass. This alternative approach can explain the astrometric data of both the S2-star and the G2 object with similar accuracy than the Schwarzschild BH scenario, but without introducing a drag force on G2 which is needed in the BH case to reconcile it with the G2 post-pericentre passage velocity data. An underlying assumption about the nature of such a DM quantum core is its absence of rotation, which is well supported by recent upper bounds on the spin of the central BH of a 0.1, based on the spatial distribution of the S-stars (Ali et al. 2020; Fragione & Loeb 2020; Peißker et al. 2020). The first results obtained in Becerra-Vergara et al. (2020) within the DM scenario have been further extended in Becerra-Vergara et al. (2021) by considering the 17 best resolved stars orbiting Sgr A*, achieving an equally good fit than in the BH paradigm. Remarkably, such a dense DM core is the central region of a continuous distribution of DM whose diluted halo explains the Galactic rotation curves (Argüelles et al. 2018; Becerra-Vergara et al. 2020, 2021). Core-halo DM distributions of this kind are obtained from the solution of the Einstein equations for a self-gravitating, finite-temperature fluid of fermions in equilibrium following the Ruffini–Argüelles–Rueda (RAR) model (Ruffini, Argüelles & Rueda 2015; Argüelles et al. 2016, 2018, 2019, 2021; Gómez et al. 2016; Gómez & Rueda 2017; Becerra-Vergara et al. 2020, 2021; Penacchioni et al. 2020; Yunis et al. 2020). These novel core-halo DM profiles, as the ones applied in this Letter, have been shown to form and remain stable in cosmological time-scales, when accounting for the quantum nature of the particles within proper relaxation mechanisms of collisionless fermions (Argüelles et al. 2021). There are other alternative scenarios for Sgr A* involving a compact object of quantum nature, e.g. a boson star composed of ultralight scalars (see e.g. Torres et al. 2000). However, unlike the ∼50–345 keV c−2 fermionic DM RAR solutions, those boson stars do not explain the Galaxy rotation curves.","Citation Text":["Peißker et al. 2020"],"Citation Start End":[[1256,1275]]} {"Identifier":"2015MNRAS.450.1012N__Cardelli,_Sarage_&_Ebbets_1991_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Cardelli, Sarage & Ebbets 1991"],"Citation Start End":[[1613,1643]]} {"Identifier":"2015MNRAS.450.1012NKeenan_et_al._1990_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Keenan et al. 1990"],"Citation Start End":[[269,287]]} {"Identifier":"2015MNRAS.450.1012NYamada,_Kanamori_&_Hirota_(1985)_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Yamada, Kanamori & Hirota (1985)"],"Citation Start End":[[595,627]]} {"Identifier":"2015MNRAS.450.1012NLeckrone_et_al._1993_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Leckrone et al. 1993"],"Citation Start End":[[1760,1780]]} {"Identifier":"2015MNRAS.450.1012NdeBruin,_Humphreys_&_Meggers_(1933)_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["deBruin, Humphreys & Meggers (1933)"],"Citation Start End":[[1847,1882]]} {"Identifier":"2015MNRAS.450.1012NMinnhagen,_Strihed_&_Petersson_(1969)_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Minnhagen, Strihed & Petersson (1969)"],"Citation Start End":[[1982,2019]]} {"Identifier":"2015MNRAS.450.1012NHumphreys_&_Paul_(1970)_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Humphreys & Paul (1970)"],"Citation Start End":[[2081,2104]]} {"Identifier":"2015MNRAS.450.1012NBredice_et_al._(1988)_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Bredice et al. (1988)"],"Citation Start End":[[2257,2278]]} {"Identifier":"2015MNRAS.450.1012NMiller,_Roig_&_Bengtson_1972_Instance_1","Paragraph":"Argon (Ar) is also one of the most abundant rare gases in the Universe and Ar ion lines are observed in solar and astrophysical plasmas as well as in the laboratory. It is observed that the spectra of early B-type stars contain a large number of unblended Ar ii lines (Keenan et al. 1990; Lanz et al. 2008). Lanz et al. analysed the blue spectra of Ar ii in the 10 B-type main-sequence stars in the Orion association and inferred about the mean abundance of Ar in the star HD 35299. Direct observation of the fine structure splittings in the ground states of Ne ii and Ar ii were carried out by Yamada, Kanamori & Hirota (1985). These two transitions were measured with frequencies 780.4240 ± 0.0011 cm−1 and 1431.5831 ± 0.0007 cm−1 for Ne ii and Ar ii, respectively. They are advantageous for infrared spectroscopy over optical, radio frequency and microwave regions to estimate the abundance of Ne and Ar. Because these infrared lines are relatively unaffected by interstellar dust, they can be easily identified by high-resolution telescopes. In fact, the considered infrared line of Ne ii is the only line that can be observed using a ground-based observatory among all other most abundant elements in the Universe at their various stages of ionization. Krypton (Kr) ion spectra were also detected in the interstellar medium (Cardelli & Mayer 1997), in the galactic disc (Cartledge, Meyer & Lauroesch 2003) and in planetary nebulae (Dinerstein 2001). With the help of the Goddard high-resolution spectrograph in the Hubble Space Telescope, many Kr ii lines have also been observed in the interstellar medium (Cardelli, Sarage & Ebbets 1991). More importantly, the materials responsible for the formation of the young early-type stars are enriched with Kr (Leckrone et al. 1993). Extensive analysis of the Kr ii spectra has been carried out by deBruin, Humphreys & Meggers (1933), who quoted uncertainties of the sharp lines of about 0.01 Å. A second analysis was carried out by Minnhagen, Strihed & Petersson (1969) for two sets of wavelength ranges, 800–1350 and 2350–2450 Å. Humphreys & Paul (1970) also reported wavelengths of the 43 lines in Kr ii most precisely from the interferometric observations, using isotropically pure 86Kr. Following this, Bredice et al. (1988) obtained 36 additional lines between 1134 and 8652 Å using an energetically excited source with an accuracy of 0.01 Å. There have been numerous attempts made in the last two decades to discover accurate values of the transition probabilities in Kr ii (Koozekanani & Trusty 1969; Levchenko 1971; Miller, Roig & Bengtson 1972) for various inter-combination transitions. Similarly, the lines of singly charged xenon (Xe ii) have been identified in many HgMn young stars, such as k Cnc, 112 Her, 46 Aql (HD 186122), 33 Gem, HR 7143, HR 7245, HR 7361, HD 175640, etc. (Whitford 1962; Bidelman 1966), which were analysed using the available spectroscopic data of Xe ii (Castelli & Hubrig 2004; Dworetsky, Persaud & Patel 2008). Yüce, Castelli & Hubrig (2011) also investigated the Xe ii lines lying in the ranges 3900–4521, 4769–7542 and 7660–8000 Å in HgMn stars. Observations of the optical lines from heavy elements, especially from radioactive atoms, in the atmosphere of Procyon have been reported (Yushchenko & Gopka 1996). It happens that the wavelength of the emission line of the 7p 2P3\/2 → 7p 2P1\/2 transition in singly ionized radon (Rn ii) is about 3216 Å and could be useful for estimating the abundance of Rn in astronomical objects.","Citation Text":["Miller, Roig & Bengtson 1972"],"Citation Start End":[[2574,2602]]} {"Identifier":"2022MNRAS.516.1081E__Milgrom_2010_Instance_1","Paragraph":"By combining observational constraints on the dynamics in galaxies with constraints from the Solar system, Milgrom (1983a) corrected the theory of gravitation at low acceleration, which could be a consequence of the quantum vacuum (Milgrom 1999; Pazy 2013; Smolin 2017; Verlinde 2017). In analogy with Newtonian dynamics, a non-relativistic Milgromian gravity theory (MOND) can be constructed by setting up a Lagrangian which, upon extremization of the action, yields a generalized Milgromian Poisson equation. Two such Lagrangians have been proposed, called AQUAL (Bekenstein & Milgrom 1984) and QUMOND (Milgrom 2010). The latter, which we adopt hereafter, yields the following generalized Poisson equation,\n(1)$$\\begin{eqnarray}\r\n\\Delta \\Phi (\\vec {x}) = 4\\pi G\\rho _{\\rm b} (\\vec {x}) + \\vec {\\nabla } \\cdot [\\tilde{v}(\\left|\\vec{\\nabla } \\phi \\right|\/a_0)\\vec {\\nabla } \\phi (\\vec {x})],\r\n\\end{eqnarray}$$or,\n(2)$$\\begin{eqnarray}\r\n\\Delta \\Phi (\\vec {x}) = 4\\pi G [\\rho _{\\rm b} (\\vec {x}) + \\rho _{\\rm ph}(\\vec {x})],\r\n\\end{eqnarray}$$where $\\rho _{\\rm b}(\\vec{x})$ is the baryonic density, $\\phi (\\vec{x})$ is the Newtonian potential that fulfils the standard Poisson equation, $\\Delta \\phi (\\vec{x})$ = 4πG$\\rho _{\\rm b}(\\vec{x})$ and Milgrom’s constant a0$\\approx \\rm 1.2 \\times 10^{-10} \\ ms^{-2} \\approx 3.8 \\ pc \\ Myr^{-2}$. The phantom dark matter (PDM) density, $\\rho _{ph}(\\vec{x})$, is not a real density distribution but a mathematical function that arises out of the non-linearity of the Poisson equation. $\\Phi (\\vec{x})$ is the total gravitational potential from which the accelerations follow, $\\vec{a} = -\\vec{\\nabla } \\vec{\\Phi }$, and $\\tilde{v}(y)$ is a transition function characterizing the theory (see Milgrom 2008, 2010, 2014; Famaey & McGaugh 2012; and Banik & Zhao 2022 for detailed reviews on the theory). $\\tilde{v}(y)$ has the limits,\n(3)$$\\begin{eqnarray}\r\n\\tilde{v}(y) \\rightarrow 0 \\,\\,\\rm {for}\\,\\, \\it y\\,\\, \\gg \\rm 1 \\,\\,\\rm {and}\\,\\, \\it \\tilde{v}(\\it y)\\,\\, \\rightarrow \\it y^{\\rm -1\/2}\\,\\, \\rm {for}\\,\\, \\it y\\,\\, \\ll \\rm 1.\r\n\\end{eqnarray}$$The above formulation deals only with linear differential equations and is shown to emerge as a natural modification of a Palatini-type formulation of Newtonian gravity. It is a member of a larger class of bipotential theories (quasi-linear formulation of MOND; QUMOND Milgrom 2010). Bekenstein & Milgrom (1984) also noted a correspondence with some theories of quark confinement using a different form of the function $\\tilde{v}$.","Citation Text":["Milgrom 2010"],"Citation Start End":[[605,617]]} {"Identifier":"2022MNRAS.516.1081E__Milgrom_2010_Instance_2","Paragraph":"By combining observational constraints on the dynamics in galaxies with constraints from the Solar system, Milgrom (1983a) corrected the theory of gravitation at low acceleration, which could be a consequence of the quantum vacuum (Milgrom 1999; Pazy 2013; Smolin 2017; Verlinde 2017). In analogy with Newtonian dynamics, a non-relativistic Milgromian gravity theory (MOND) can be constructed by setting up a Lagrangian which, upon extremization of the action, yields a generalized Milgromian Poisson equation. Two such Lagrangians have been proposed, called AQUAL (Bekenstein & Milgrom 1984) and QUMOND (Milgrom 2010). The latter, which we adopt hereafter, yields the following generalized Poisson equation,\n(1)$$\\begin{eqnarray}\r\n\\Delta \\Phi (\\vec {x}) = 4\\pi G\\rho _{\\rm b} (\\vec {x}) + \\vec {\\nabla } \\cdot [\\tilde{v}(\\left|\\vec{\\nabla } \\phi \\right|\/a_0)\\vec {\\nabla } \\phi (\\vec {x})],\r\n\\end{eqnarray}$$or,\n(2)$$\\begin{eqnarray}\r\n\\Delta \\Phi (\\vec {x}) = 4\\pi G [\\rho _{\\rm b} (\\vec {x}) + \\rho _{\\rm ph}(\\vec {x})],\r\n\\end{eqnarray}$$where $\\rho _{\\rm b}(\\vec{x})$ is the baryonic density, $\\phi (\\vec{x})$ is the Newtonian potential that fulfils the standard Poisson equation, $\\Delta \\phi (\\vec{x})$ = 4πG$\\rho _{\\rm b}(\\vec{x})$ and Milgrom’s constant a0$\\approx \\rm 1.2 \\times 10^{-10} \\ ms^{-2} \\approx 3.8 \\ pc \\ Myr^{-2}$. The phantom dark matter (PDM) density, $\\rho _{ph}(\\vec{x})$, is not a real density distribution but a mathematical function that arises out of the non-linearity of the Poisson equation. $\\Phi (\\vec{x})$ is the total gravitational potential from which the accelerations follow, $\\vec{a} = -\\vec{\\nabla } \\vec{\\Phi }$, and $\\tilde{v}(y)$ is a transition function characterizing the theory (see Milgrom 2008, 2010, 2014; Famaey & McGaugh 2012; and Banik & Zhao 2022 for detailed reviews on the theory). $\\tilde{v}(y)$ has the limits,\n(3)$$\\begin{eqnarray}\r\n\\tilde{v}(y) \\rightarrow 0 \\,\\,\\rm {for}\\,\\, \\it y\\,\\, \\gg \\rm 1 \\,\\,\\rm {and}\\,\\, \\it \\tilde{v}(\\it y)\\,\\, \\rightarrow \\it y^{\\rm -1\/2}\\,\\, \\rm {for}\\,\\, \\it y\\,\\, \\ll \\rm 1.\r\n\\end{eqnarray}$$The above formulation deals only with linear differential equations and is shown to emerge as a natural modification of a Palatini-type formulation of Newtonian gravity. It is a member of a larger class of bipotential theories (quasi-linear formulation of MOND; QUMOND Milgrom 2010). Bekenstein & Milgrom (1984) also noted a correspondence with some theories of quark confinement using a different form of the function $\\tilde{v}$.","Citation Text":["Milgrom","2010"],"Citation Start End":[[1730,1737],[1744,1748]]} {"Identifier":"2022MNRAS.516.1081E__Milgrom_2010_Instance_3","Paragraph":"By combining observational constraints on the dynamics in galaxies with constraints from the Solar system, Milgrom (1983a) corrected the theory of gravitation at low acceleration, which could be a consequence of the quantum vacuum (Milgrom 1999; Pazy 2013; Smolin 2017; Verlinde 2017). In analogy with Newtonian dynamics, a non-relativistic Milgromian gravity theory (MOND) can be constructed by setting up a Lagrangian which, upon extremization of the action, yields a generalized Milgromian Poisson equation. Two such Lagrangians have been proposed, called AQUAL (Bekenstein & Milgrom 1984) and QUMOND (Milgrom 2010). The latter, which we adopt hereafter, yields the following generalized Poisson equation,\n(1)$$\\begin{eqnarray}\r\n\\Delta \\Phi (\\vec {x}) = 4\\pi G\\rho _{\\rm b} (\\vec {x}) + \\vec {\\nabla } \\cdot [\\tilde{v}(\\left|\\vec{\\nabla } \\phi \\right|\/a_0)\\vec {\\nabla } \\phi (\\vec {x})],\r\n\\end{eqnarray}$$or,\n(2)$$\\begin{eqnarray}\r\n\\Delta \\Phi (\\vec {x}) = 4\\pi G [\\rho _{\\rm b} (\\vec {x}) + \\rho _{\\rm ph}(\\vec {x})],\r\n\\end{eqnarray}$$where $\\rho _{\\rm b}(\\vec{x})$ is the baryonic density, $\\phi (\\vec{x})$ is the Newtonian potential that fulfils the standard Poisson equation, $\\Delta \\phi (\\vec{x})$ = 4πG$\\rho _{\\rm b}(\\vec{x})$ and Milgrom’s constant a0$\\approx \\rm 1.2 \\times 10^{-10} \\ ms^{-2} \\approx 3.8 \\ pc \\ Myr^{-2}$. The phantom dark matter (PDM) density, $\\rho _{ph}(\\vec{x})$, is not a real density distribution but a mathematical function that arises out of the non-linearity of the Poisson equation. $\\Phi (\\vec{x})$ is the total gravitational potential from which the accelerations follow, $\\vec{a} = -\\vec{\\nabla } \\vec{\\Phi }$, and $\\tilde{v}(y)$ is a transition function characterizing the theory (see Milgrom 2008, 2010, 2014; Famaey & McGaugh 2012; and Banik & Zhao 2022 for detailed reviews on the theory). $\\tilde{v}(y)$ has the limits,\n(3)$$\\begin{eqnarray}\r\n\\tilde{v}(y) \\rightarrow 0 \\,\\,\\rm {for}\\,\\, \\it y\\,\\, \\gg \\rm 1 \\,\\,\\rm {and}\\,\\, \\it \\tilde{v}(\\it y)\\,\\, \\rightarrow \\it y^{\\rm -1\/2}\\,\\, \\rm {for}\\,\\, \\it y\\,\\, \\ll \\rm 1.\r\n\\end{eqnarray}$$The above formulation deals only with linear differential equations and is shown to emerge as a natural modification of a Palatini-type formulation of Newtonian gravity. It is a member of a larger class of bipotential theories (quasi-linear formulation of MOND; QUMOND Milgrom 2010). Bekenstein & Milgrom (1984) also noted a correspondence with some theories of quark confinement using a different form of the function $\\tilde{v}$.","Citation Text":["Milgrom 2010"],"Citation Start End":[[2354,2366]]} {"Identifier":"2022MNRAS.511.5180P__Fossati_et_al._2016_Instance_1","Paragraph":"When considering only spaxels with S\/N > 5 for each emission line contributing to a given BPT diagram, we are left only with spaxels on the galaxy discs of CGCG097–079 and CGCG097–073 and their immediate surroundings where the emission line flux is high enough to obtain robust line ratios in individual spaxels. We present these results in Fig. 8. The top panel shows the distribution of individual spaxels in the aforementioned BPT diagrams. Each spaxel is colour coded by its distance from the lines separating the region dominated by photo-ionization from the one dominated by active galactic nuclei (AGNs) or shocks, following the separation of Kauffmann et al. (2003). The distributions of line ratios from nuclear spectra of a sample of 50 000 SDSS galaxies at 0.03 z 0.08 whose emission lines are detected at S\/N > 5 (Fossati et al. 2016) are shown with grey contours. The innermost to outermost contours include the 25, 50, 75, and 98 per cent of the full data set, respectively. However, this SDSS sample only represents the nuclear properties of galaxies which might be different from their outskirts which are likely providing most of the stripped gas. To overcome this possible issue, we add to the diagnostic diagrams the same density contours from a sample of individual spaxels from the DR17 of the Mapping Nearby Galaxies at APO (MaNGA) IFU survey of ∼10 000 galaxies (Abdurro’uf et al. 2021). For each BPT diagram, we selected spaxels outside the effective radius (R > 1 Re) of each individual galaxy whose emission lines are detected at S\/N > 5. This sample includes roughly half a million spaxels in the BPT diagram using the fainter [O i] line and roughly 2 million spaxels in the other two BPT diagrams. Density contours from this sample (at the same levels mentioned above) are shown in pink in Fig. 8. We also verified that by using spaxels from the entire galaxy discs, the density contours would appear very similar to the SDSS sample, due larger weight given to the inner parts of the discs. Despite the differences seen in these two reference samples, the BPT diagnostic made using [O i]\/H α shows enhanced [O i]\/H α in the RPS tails that appear not to be typical neither of the galaxy nuclei nor of their disc outskirts. We will discuss this point in a more quantitative fashion in Section 5.1. In the middle and bottom panels, we show the spatial distribution of the spaxels from the two galaxies, with points colour coded as above.","Citation Text":["Fossati et al. 2016"],"Citation Start End":[[828,847]]} {"Identifier":"2020MNRAS.491.1656A__Benitez-Llambay_et_al._2019_Instance_1","Paragraph":"The sensitivity of dwarfs to galaxy formation physics, like the gas density at which stars form (e.g. Kravtsov 2003; Saitoh et al. 2008) or the details of galactic outflows (e.g. Read et al. 2006b), makes them a natural ‘rosetta stone’ for constraining galaxy formation models. Early work simulating dwarf galaxies focused on high resolution small box simulations, stopping at high redshift (z ∼ 5–10) to avoid gravitational collapse on the scale of the box (e.g. Abel et al. 1998; Gnedin & Kravtsov 2006; Read et al. 2006b; Mashchenko, Wadsley & Couchman 2008). These simulations demonstrated that stellar winds, SN feedback, and ionizing radiation combine to prevent star formation in halo masses below ∼107–8 M⊙ (Read et al. 2006b; Bland-Hawthorn, Sutherland & Webster 2015). Furthermore, once cooling below 104 K is permitted and gas is allowed to reach high densities $n_{\\rm max} {\\gtrsim}10\\,{\\rm cm}^{-3}$ (requiring a spatial and mass resolution better than $\\Delta x {\\lesssim}100$ pc and mmin 103 M⊙; Pontzen & Governato 2012; Benitez-Llambay et al. 2019; Bose et al. 2019; Dutton et al. 2019), star formation becomes much more stochastic and violent (Mashchenko et al. 2008; Pontzen & Governato 2012; Dutton et al. 2019). The repeated action of gas cooling and blow-out due to feedback expels DM from the galaxy centre, transforming an initially dense DM cusp to a core (e.g. Read & Gilmore 2005; Pontzen & Governato 2012). Finally, independent of any internal sources of feedback energy, cosmic reionization can halt star formation in low-mass galaxies (e.g. Gnedin & Kravtsov 2006). Dwarfs that have not reached a mass of $M_{200} {\\gtrsim}10^8$ M⊙ (see Section 2.4 for a definition of M200) by the redshift that reionization begins (z ∼ 8–10; Gnedin & Kaurov 2014; Ocvirk et al. 2018) are gradually starved of fresh cold gas, causing their star formation to shut down by a redshift of z ∼ 4 (Oñorbe et al. 2015). This is similar to the age of nearby ‘ultra-faint’ dwarf galaxies (UFDs) that have $M_* {\\lesssim}10^5$ M⊙, suggesting that at least some of these are likely to be relics from reionization, inhabiting pre-infall halo masses in the range M200 ∼ 108–9 M⊙ (Gnedin & Kravtsov 2006; Bovill & Ricotti 2009, 2011; Brown et al. 2014; Weisz et al. 2014; Jethwa, Erkal & Belokurov 2018; Read & Erkal 2019).","Citation Text":["Benitez-Llambay et al. 2019"],"Citation Start End":[[1039,1066]]} {"Identifier":"2022ApJ...927..237I__Izumi_et_al._2019_Instance_1","Paragraph":"The empirical relation between the mass of SMBHs and the properties of their host galaxies is considered to be one of the most important outcomes caused by their coevolution over the cosmic timescale (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Kormendy & Ho 2013). Theoretical models for explaining the tight correlations have been proposed, but the origin is still unclear. To understand the nature of these correlations, it is critically important to study them beyond the local universe, characterizing how and when the relations have been established and evolved until now. So far, a large number of observational studies have extensively investigated the redshift dependence of the BH-to-bulge mass ratio of M\n•\/M\n⋆ and overall suggested its positive redshift dependence, i.e., the ratio increases with redshift (Bennert et al. 2011; Schramm & Silverman 2013; Ding et al. 2020). Beyond z ∼ 6, the Atacama Large Millimeter\/submillimeter Array (ALMA) is a powerful tool to measure the dynamical mass of gas in quasar host galaxies and allows us to explore the early stage of the BH\/galaxy correlation (e.g., Wang et al. 2010, 2013; Venemans et al. 2017). In addition, observations with the Subaru HSC provide low-luminosity and less-massive BH samples, which are unique populations to determine the M\n•\/M\n⋆ ratio at z > 6 (Izumi et al. 2019, 2021). Figure 11 shows the distribution of z > 6 quasars compiled in Izumi et al. (2021), together with those in the local universe (Kormendy & Ho 2013). First, the brightest z > 6 quasars with M\n1450 −25 mag tend to have M\n•\/M\n⋆ ratios higher than those seen in the local universe. Namely, the mass ratio for those brightest objects is boosted by a factor of ∼10 (blue dashed line; Pensabene et al. 2020). On the other hand, the fainter quasars with M\n1450 >−25 mag appear to follow the local relation, although those BHs are considered to grow at rates of ≳ 0.05 SFR and will be overmassive at lower redshifts.\n15\n\n\n15\nIn this paper, overmassive BHs are referred to as a BH population with a BH-to-galaxy mass ratio higher than that observed in the local universe; \n\n\n\nM•\/M⋆≳4.9−0.5+0.6×10−3\n\n (Kormendy & Ho 2013). We employ this terminology to clearly contrast the difference between the overmassive and undermassive BH population with respect to the local value (see Figure 11). Note that a previous study by Agarwal et al. (2013) used a term of “obese BH,” which refers to a BH population dominating over the stellar mass of its host galaxy at least in the initial growing stage (i.e., M\n•\/M\n⋆ > 1). We note that for all of the z > 6 samples, the values of the x-axis are not the bulge mass of their host galaxies but the dynamical mass measured by [C ii] 158 μm lines. In general, the dynamical mass is considered to be higher than the true bulge mass. With a high-resolution ALMA observation, Izumi et al. (2021) found that the gas dynamics of the core component of a low-luminosity quasar at z = 7.07 (HSC J1243+0100) is governed by rotation associated with a compact bulge and estimated its mass as ∼50% of the [C ii]-based dynamical mass. Therefore, the correlation at z > 6 might be shifted to the left if the conversion factor from the dynamical mass to the bulge mass is taken into account.","Citation Text":["Izumi et al. 2019"],"Citation Start End":[[1338,1355]]} {"Identifier":"2018MNRAS.477..741C__Eisenstein_&_Hu_1999_Instance_1","Paragraph":"Small fluctuations δ in the distribution of dark matter grow, as long as they are in the linear regime |δ| ≪ 1, according to the growth function D+(a) (Linder & Jenkins 2003; Wang & Steinhardt 1998),\n(3)\r\n\\begin{equation}\r\n\\frac{\\mathrm{d}^2}{\\mathrm{d}a^2}D_+(a) + \\frac{2-q}{a}\\frac{\\mathrm{d}}{\\mathrm{d}a}D_+(a) - \\frac{3}{2a^2}\\Omega _\\mathrm{m}(a) D_+(a) = 0,\r\n\\end{equation}\r\nand their statistics is characterized by the spectrum $\\langle \\delta (\\boldsymbol {k})\\delta ^*(\\boldsymbol {k}^\\prime )\\rangle = (2\\pi )^3\\delta _{\\rm D}(\\boldsymbol {k}-\\boldsymbol {k}^\\prime )P_\\delta (k)$. Inflation generates a spectrum of the form $P_\\delta (k)\\propto k^{n_s}T^2(k)$ with the transfer function T(k) (Eisenstein & Hu 1999, 1998) which is normalized to the variance $\\sigma _8^2$ smoothed to the scale of 8 Mpc h−1,\n(4)\r\n\\begin{equation}\r\n\\sigma _8^2 = \\int _0^\\infty \\frac{k^2\\mathrm{d}k}{2\\pi ^2}\\, W^2(8\\,{\\rm }\\mathrm{Mpc}\\, h^{-1}\\times k)\\,P_\\delta (k),\r\n\\end{equation}\r\nwith a Fourier-transformed spherical top-hat W(x) = 3j1(x)\/x as the filter function. From the CDM spectrum of the density perturbation, the spectrum of the Newtonian gravitational potential Φ can be obtained,\n(5)\r\n\\begin{equation}\r\nP_\\Phi (k; \\chi ) = \\left(\\frac{3 \\Omega _\\mathrm{m} H_0^2}{2} \\right)^2 k^{-4} P_\\delta (k; \\chi ) \\propto \\left(\\frac{3\\Omega _\\mathrm{m}H_0^2}{2}\\right)^2\\,k^{n_s-4}\\,T(k)^2,\r\n\\end{equation}\r\nby applying the comoving Poisson equation $\\Delta \\Phi = \\frac{3 \\Omega _\\mathrm{m}H_0^2}{2} \\delta$ for deriving the gravitational potential Φ from the density δ. With equation (3) yielding a solution for the homogeneous growth of the density contrast. It should be noted that velocities at linear order are obtained from the continuity equation,\n(6)\r\n\\begin{equation}\r\n\\boldsymbol {\\nabla } \\cdot \\boldsymbol {\\upsilon } = - a \\dot{ \\delta },\r\n\\end{equation}\r\nsuch that in Fourier space,\n(7)\r\n\\begin{equation}\r\n\\boldsymbol {\\upsilon }_{\\rm k} = a H(a) \\frac{\\mathrm{d}\\ln ( D_+)}{\\mathrm{d}\\ln (a)} \\frac{ \\boldsymbol {k}}{k^2} \\boldsymbol { \\delta }_{\\rm k}.\r\n\\end{equation}\r\n","Citation Text":["Eisenstein & Hu 1999"],"Citation Start End":[[706,726]]} {"Identifier":"2022MNRAS.516.5618P__Schroetter_et_al._2019_Instance_1","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Schroetter et al. 2019"],"Citation Start End":[[1175,1197]]} {"Identifier":"2022MNRAS.516.5618P__Schroetter_et_al._2019_Instance_2","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Schroetter et al. 2019"],"Citation Start End":[[2986,3008]]} {"Identifier":"2022MNRAS.516.5618PFumagalli,_O’Meara_&_Prochaska_2016_Instance_1","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Fumagalli, O’Meara & Prochaska 2016"],"Citation Start End":[[1336,1371]]} {"Identifier":"2022MNRAS.516.5618PBoettcher_et_al._2021_Instance_1","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Boettcher et al. 2021"],"Citation Start End":[[1660,1681]]} {"Identifier":"2022MNRAS.516.5618PNielsen_et_al._2020_Instance_1","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Nielsen et al. 2020"],"Citation Start End":[[1885,1904]]} {"Identifier":"2022MNRAS.516.5618PRichard_et_al._2019_Instance_1","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Richard et al. 2019"],"Citation Start End":[[2058,2077]]} {"Identifier":"2022MNRAS.516.5618PKlitsch_et_al._2018_Instance_1","Paragraph":"Recent technological advances related to 3D Integral Field Spectroscopy (IFS), which produces data cubes where each pixel on the image has a spectrum, have opened a new window for examining the CGM gas. This approach combines the information gathered in absorption against background sources (whose lines of sight pass through a galaxy’s CGM) with traditional emission-based properties of galaxies. Following at least two decades of limited success in identifying the galaxies associated with quasar absorbers, IFS have open a new era in establishing the relation between absorption and emission with high success rates. Early efforts with near-infrared IFS VLT\/SINFONI (Bouché et al. 2007; Péroux et al. 2011; Péroux et al. 2013, 2016) led to efficient discoveries of star-forming galaxies associated with Mg ii and H i absorbers at z ∼ 2 (see also Rudie, Newman & Murphy 2017; Joshi et al. 2021). The optical IFS VLT\/MUSE (Bacon et al. 2010) has proved to be a true game-changer in the field. Early on, the MUSE Guaranteed Time Observations (GTO) team established surveys including MUSE-QuBES (Muzahid et al. 2020) and MEGAFLOW (Bouché et al. 2016; Schroetter et al. 2016; Schroetter et al. 2019; Zabl et al. 2019) to relate gas traced by absorbers to galaxies. In a parallel effort, the MAGG survey targets higher redshift galaxies (Fumagalli, O’Meara & Prochaska 2016; Dutta et al. 2020; Lofthouse et al. 2020). The Cosmic Ultraviolet Baryon Survey CUBS instead is absorption-blind and uncovers new quasar absorbers in a wide range of column densities (ranging from few times 16.0 $\\rm{log}\\,\\,{\\it N}(\\rm{H\\,\\,{\\small I}})$20.1) at z1 (Chen et al. 2020; Boettcher et al. 2021; Cooper et al. 2021; Zahedy et al. 2021). By extending to bluer wavelengths, the optical IFS Keck\/KCWI (Martin et al. 2010) has enabled similar studies at higher spectral resolution (Martin et al. 2019; Nielsen et al. 2020). BlueMUSE, a blue-optimized, medium spectral resolution IFS based on the MUSE concept and proposed for the Very Large Telescope is also under planning (Richard et al. 2019). Contemporary to these works, ALMA - which can be viewed as an IFS at mm-wavelengths - has enabled the detections of both CO and [CII] emission in galaxies associated with strong quasar absorbers at intermediate and high redshifts, respectively (Neeleman et al. 2016; Kanekar et al. 2018; Klitsch et al. 2018; Neeleman et al. 2018; Neeleman et al. 2019; Péroux et al. 2019; Klitsch et al. 2021; Szakacs et al. 2021a). These lines enable us to trace the colder (∼100K) and denser phase of the neutral gas: the molecular hydrogen, H2. The molecular gas constitutes the ultimate phase of the gas reservoir from which stars form and hence is an essential link to the baryon cycle. Together, these IFS observations have provided unique information on the resolved galaxy kinematics which can then be combined with the gas dynamics to probe gas flows in the CGM regions (Bouché et al. 2013; Rahmani et al. 2018a; Schroetter et al. 2019; Zabl et al. 2019; Neeleman et al. 2020; Szakacs et al. 2021a).","Citation Text":["Klitsch et al. 2018"],"Citation Start End":[[2368,2387]]} {"Identifier":"2022ApJ...936...95W___2006_Instance_1","Paragraph":"The observed X-ray emission from AGNs may be modified by line-of-sight obscuration, resulting in lower observed X-ray fluxes than those expected from the α\nOX–L\n2500 Å relation. A common approach to parameterize the amount of X-ray weakness uses the Δα\nOX parameter, defined as the difference between the observed α\nOX value and the α\nOX value expected from the α\nOX–L\n2500 Å relation; Δα\nOX = − 0.3838 thus corresponds to a factor of X-ray weakness of 10 at rest-frame 2 keV. Type 2 AGNs are generally X-ray obscured, likely due to the dusty “torus” (e.g., Netzer 2015; Hickox & Alexander 2018). Type 1 AGNs may also have X-ray obscuration from largely dust-free gas.\n13\n\n\n13\nSimilar obscuration from dust-free gas might also be present in some of the type 2 AGNs, though usually not distinguishable from the torus obscuration. For example, broad absorption line (BAL) quasars, which are characterized by blueshifted broad UV absorption lines (e.g., C iv\nλ1549), generally show weak X-ray emission (e.g., Gallagher et al. 2002, 2006; Fan et al. 2009; Gibson et al. 2009). One frequently adopted physical model for BAL quasars is the disk wind model, where the observed BALs originate from an outflowing equatorial wind launched from the accretion disk and radiatively driven by UV-line pressure (e.g., Murray et al. 1995; Proga et al. 2000; Matthews et al. 2016). This model usually invokes “shielding” gas between the wind and nucleus or a clumpy wind (e.g., Baskin et al. 2014; Matthews et al. 2016; Giustini & Proga 2019) to provide obscuration of the nuclear extreme-UV (EUV) and X-ray radiation, which might otherwise overionize the wind and hamper radiative acceleration. BAL quasars are considered generally to have larger inclination angles than non-BAL quasars, with the line of sight to the UV continuum region of the accretion disk intersecting the wind, leading to the observed BALs. The line of sight to the X-ray-emitting corona, though not necessarily the same as the UV line of sight, is likely also through the shielding gas or the clumpy wind, resulting in the often-observed X-ray weakness (e.g., Figure 1 of Luo et al. 2013). Besides BAL quasars, a small fraction (5.8% ± 0.7%) of non-BAL type 1 quasars have been found to be X-ray weak, likely due to absorption (e.g., Pu et al. 2020). They may share a similar nature to the BAL quasars; they do not show any UV BALs, probably due to geometric effects (e.g., small inclination angles) or a low velocity of the wind along the UV line of sight (e.g., Giustini & Proga 2019).","Citation Text":["Gallagher et al.","2006"],"Citation Start End":[[1006,1022],[1029,1033]]} {"Identifier":"2019AandA...626A..47H__Danieli_et_al._(2019)_Instance_1","Paragraph":"The recently observed ultra-diffuse galaxy NGC 1052-DF2 with a dark matter mass 400 times smaller than theoretically expected based on an internal velocity dispersion of \n\n\n\n\nσ\nintr\n\n=\n3\n.\n\n2\n\n+\n5.5\n\n\n−\n3.2\n\n\n\n\n$ \\sigma_\\mathrm{{intr}}=3.2_{+5.5}^{-3.2} $\n\n\n km s−1, seems to support the existence of dark matter-free galaxies in our Universe (van Dokkum et al. 2018a). van Dokkum et al. (2018b) derived a revised internal velocity dispersion of \n\n\n\n\nσ\nintr\n\n=\n7\n.\n\n8\n\n+\n5.2\n\n\n−\n2.2\n\n\n\n\n$ \\sigma_\\mathrm{{intr}}=7.8_{+5.2}^{-2.2} $\n\n\n km s−1 using ten GCs surrounding this galaxy. Danieli et al. (2019) measured a stellar velocity dispersion of \n\n\n\n\nσ\nstars\n\n=\n8\n.\n\n5\n\n+\n2.3\n\n\n−\n3.1\n\n\n\n\n$ \\sigma_\\mathrm{{stars}}=8.5_{+2.3}^{-3.1} $\n\n\n km s−1 with the Keck Cosmic Web Imager (KCWI). The high relative velocity to the nearby massive elliptical galaxy NGC 1052 underpins the theory that this observed dark matter-lacking galaxy is indeed a TDG. However, Martin et al. (2018) revised the internal velocity of NGC 1052-DF2 to a 90 percent upper limit of 17.3 km s−1 corresponding to a mass-to-light ratio of M\/LV   8.1 Υ⊙, consistent with many Local Group dwarf galaxies. Emsellem et al. (2019) obtain M\/LV in the range 3.5−3.9(±1.8) Υ⊙ using the Jeans model if located at D = 20 Mpc. This result would be close to the 2σ upper limit of the study from Martin et al. (2018). The lack of dark matter and the unusual high luminosity of ten globular cluster-like objects surrounding this galaxy only holds if NGC 1052-DF2 is located at a distance of around 20 Mpc (van Dokkum et al. 2018a). Danieli et al. (2019) confirmed that DF2 is dark matter deficient and concluded that it is an outlier to dwarf galaxies of the Local Group. In contrast to that, Trujillo et al. (2019) derived a revised distance to NGC 1052-DF2 of D = 13.0 ± 0.4 Mpc based on five redshift-independent measurements including the tip of the red giant branch and the surface brightness fluctuation method. Thus, NGC 1052-DF2 would be a dwarf galaxy with an ordinary dark matter content Mhalo\/Mstellar >  20 and a normal globular cluster population. Meanwhile, van Dokkum et al. (2019) reported that the dwarf galaxy NGC 1052-DF4 also lacks dark matter and is found at a distance of D = 20 Mpc.","Citation Text":["Danieli et al. (2019)","Danieli et al. (2019)"],"Citation Start End":[[581,602],[1583,1604]]} {"Identifier":"2022ApJ...925...30L__Liu_et_al._2021_Instance_1","Paragraph":"The angular dispersion function method (hereafter the ADF method; Falceta-Gonçalves et al. 2008; Hildebrand et al. 2009; Houde et al. 2009, 2016) analytically accounts for various of effects that may affect the measured angular dispersion. Based on different effects considered, the ADF methods can be divided into the structure function method (hereafter the Hil09 method; Hildebrand et al. 2009), the autocorrelation function method for single-dish observations (hereafter the Hou09 method; Houde et al. 2009), and the autocorrelation function method for interferometer observations (hereafter the Hou16 method; Houde et al. 2016). Similarly, we adopt the correction factors in Liu et al. (2021) for strong field models. For the Hil09 method, the corrected plane-of-sky uniform magnetic field strength is estimated as\n6\n\n\n\nBposu,Hil09,est∼0.1μ0ρδvlos〈Bt2〉〈B02〉−12Hil09\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n7\n\n\n\nBpostot,Hil09,est∼0.21μ0ρδvlos〈Bt2〉〈B2〉−12Hil09,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hil09\n\n is the turbulent-to-total field strength ratio derived from this method. We do not calculate \n\n\n\nBposu,Hil09,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09>0.1\n\n (Liu et al. 2021). For the Hou09 and Hou16 methods, the corrected plane-of-sky uniform magnetic field strength is estimated as\n8\n\n\n\nBposu,Hou,est∼0.19μ0ρδvlos〈Bt2〉〈B02〉−12Hou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n9\n\n\n\nBpostot,Hou,est∼0.39μ0ρδvlos〈Bt2〉〈B2〉−12Hou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hou\n\n is the turbulent-to-total field strength ratio derived from the two methods. Due to the limitation that the angular dispersion cannot exceed the value expected for a random field, the maximum derivable turbulent-to-ordered field strength ratio from the ADF methods is 0.76 (Liu et al. 2021). Thus, if the derived \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is greater than 0.76, the assumptions underlying the ADF methods on accounting for the line-of-sight signal integration may not be valid, which could lead to overestimation of the turbulent-to-ordered field strength ratio and underestimation of the field strength. In this situation, we adopt the turbulent-to-ordered field strength ratio \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou\n\n and the turbulent-to-total field strength ratio \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)nosiHou\n\n without accounting for the line-of-sight signal integration and apply the same correction factors as those for the Hil09 method. Then the corrected plane-of-sky uniform magnetic field strength is estimated as\n10\n\n\n\nBposu,Hou,est∼0.1μ0ρδvlos(〈Bt2〉〈B02〉−12)nosiHou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n11\n\n\n\nBpostot,Hou,est∼0.21μ0ρδvlos(〈Bt2〉〈B2〉−12)nosiHou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou=((〈Bt2〉\/〈B02〉)0.5)Hou\/Nadf\n\n. N\nadf is the number of turbulent fluid elements along the line of sight. Similarly, we do not calculate \n\n\n\nBposu,Hou,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou>0.1\n\n (Liu et al. 2021).","Citation Text":["Liu et al. (2021)"],"Citation Start End":[[680,697]]} {"Identifier":"2022ApJ...925...30L__Liu_et_al._2021_Instance_2","Paragraph":"The angular dispersion function method (hereafter the ADF method; Falceta-Gonçalves et al. 2008; Hildebrand et al. 2009; Houde et al. 2009, 2016) analytically accounts for various of effects that may affect the measured angular dispersion. Based on different effects considered, the ADF methods can be divided into the structure function method (hereafter the Hil09 method; Hildebrand et al. 2009), the autocorrelation function method for single-dish observations (hereafter the Hou09 method; Houde et al. 2009), and the autocorrelation function method for interferometer observations (hereafter the Hou16 method; Houde et al. 2016). Similarly, we adopt the correction factors in Liu et al. (2021) for strong field models. For the Hil09 method, the corrected plane-of-sky uniform magnetic field strength is estimated as\n6\n\n\n\nBposu,Hil09,est∼0.1μ0ρδvlos〈Bt2〉〈B02〉−12Hil09\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n7\n\n\n\nBpostot,Hil09,est∼0.21μ0ρδvlos〈Bt2〉〈B2〉−12Hil09,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hil09\n\n is the turbulent-to-total field strength ratio derived from this method. We do not calculate \n\n\n\nBposu,Hil09,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09>0.1\n\n (Liu et al. 2021). For the Hou09 and Hou16 methods, the corrected plane-of-sky uniform magnetic field strength is estimated as\n8\n\n\n\nBposu,Hou,est∼0.19μ0ρδvlos〈Bt2〉〈B02〉−12Hou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n9\n\n\n\nBpostot,Hou,est∼0.39μ0ρδvlos〈Bt2〉〈B2〉−12Hou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hou\n\n is the turbulent-to-total field strength ratio derived from the two methods. Due to the limitation that the angular dispersion cannot exceed the value expected for a random field, the maximum derivable turbulent-to-ordered field strength ratio from the ADF methods is 0.76 (Liu et al. 2021). Thus, if the derived \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is greater than 0.76, the assumptions underlying the ADF methods on accounting for the line-of-sight signal integration may not be valid, which could lead to overestimation of the turbulent-to-ordered field strength ratio and underestimation of the field strength. In this situation, we adopt the turbulent-to-ordered field strength ratio \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou\n\n and the turbulent-to-total field strength ratio \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)nosiHou\n\n without accounting for the line-of-sight signal integration and apply the same correction factors as those for the Hil09 method. Then the corrected plane-of-sky uniform magnetic field strength is estimated as\n10\n\n\n\nBposu,Hou,est∼0.1μ0ρδvlos(〈Bt2〉〈B02〉−12)nosiHou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n11\n\n\n\nBpostot,Hou,est∼0.21μ0ρδvlos(〈Bt2〉〈B2〉−12)nosiHou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou=((〈Bt2〉\/〈B02〉)0.5)Hou\/Nadf\n\n. N\nadf is the number of turbulent fluid elements along the line of sight. Similarly, we do not calculate \n\n\n\nBposu,Hou,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou>0.1\n\n (Liu et al. 2021).","Citation Text":["Liu et al. 2021"],"Citation Start End":[[1275,1290]]} {"Identifier":"2022ApJ...925...30L__Liu_et_al._2021_Instance_3","Paragraph":"The angular dispersion function method (hereafter the ADF method; Falceta-Gonçalves et al. 2008; Hildebrand et al. 2009; Houde et al. 2009, 2016) analytically accounts for various of effects that may affect the measured angular dispersion. Based on different effects considered, the ADF methods can be divided into the structure function method (hereafter the Hil09 method; Hildebrand et al. 2009), the autocorrelation function method for single-dish observations (hereafter the Hou09 method; Houde et al. 2009), and the autocorrelation function method for interferometer observations (hereafter the Hou16 method; Houde et al. 2016). Similarly, we adopt the correction factors in Liu et al. (2021) for strong field models. For the Hil09 method, the corrected plane-of-sky uniform magnetic field strength is estimated as\n6\n\n\n\nBposu,Hil09,est∼0.1μ0ρδvlos〈Bt2〉〈B02〉−12Hil09\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n7\n\n\n\nBpostot,Hil09,est∼0.21μ0ρδvlos〈Bt2〉〈B2〉−12Hil09,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hil09\n\n is the turbulent-to-total field strength ratio derived from this method. We do not calculate \n\n\n\nBposu,Hil09,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09>0.1\n\n (Liu et al. 2021). For the Hou09 and Hou16 methods, the corrected plane-of-sky uniform magnetic field strength is estimated as\n8\n\n\n\nBposu,Hou,est∼0.19μ0ρδvlos〈Bt2〉〈B02〉−12Hou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n9\n\n\n\nBpostot,Hou,est∼0.39μ0ρδvlos〈Bt2〉〈B2〉−12Hou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hou\n\n is the turbulent-to-total field strength ratio derived from the two methods. Due to the limitation that the angular dispersion cannot exceed the value expected for a random field, the maximum derivable turbulent-to-ordered field strength ratio from the ADF methods is 0.76 (Liu et al. 2021). Thus, if the derived \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is greater than 0.76, the assumptions underlying the ADF methods on accounting for the line-of-sight signal integration may not be valid, which could lead to overestimation of the turbulent-to-ordered field strength ratio and underestimation of the field strength. In this situation, we adopt the turbulent-to-ordered field strength ratio \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou\n\n and the turbulent-to-total field strength ratio \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)nosiHou\n\n without accounting for the line-of-sight signal integration and apply the same correction factors as those for the Hil09 method. Then the corrected plane-of-sky uniform magnetic field strength is estimated as\n10\n\n\n\nBposu,Hou,est∼0.1μ0ρδvlos(〈Bt2〉〈B02〉−12)nosiHou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n11\n\n\n\nBpostot,Hou,est∼0.21μ0ρδvlos(〈Bt2〉〈B2〉−12)nosiHou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou=((〈Bt2〉\/〈B02〉)0.5)Hou\/Nadf\n\n. N\nadf is the number of turbulent fluid elements along the line of sight. Similarly, we do not calculate \n\n\n\nBposu,Hou,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou>0.1\n\n (Liu et al. 2021).","Citation Text":["Liu et al. 2021"],"Citation Start End":[[1966,1981]]} {"Identifier":"2022ApJ...925...30L__Liu_et_al._2021_Instance_4","Paragraph":"The angular dispersion function method (hereafter the ADF method; Falceta-Gonçalves et al. 2008; Hildebrand et al. 2009; Houde et al. 2009, 2016) analytically accounts for various of effects that may affect the measured angular dispersion. Based on different effects considered, the ADF methods can be divided into the structure function method (hereafter the Hil09 method; Hildebrand et al. 2009), the autocorrelation function method for single-dish observations (hereafter the Hou09 method; Houde et al. 2009), and the autocorrelation function method for interferometer observations (hereafter the Hou16 method; Houde et al. 2016). Similarly, we adopt the correction factors in Liu et al. (2021) for strong field models. For the Hil09 method, the corrected plane-of-sky uniform magnetic field strength is estimated as\n6\n\n\n\nBposu,Hil09,est∼0.1μ0ρδvlos〈Bt2〉〈B02〉−12Hil09\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n7\n\n\n\nBpostot,Hil09,est∼0.21μ0ρδvlos〈Bt2〉〈B2〉−12Hil09,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hil09\n\n is the turbulent-to-total field strength ratio derived from this method. We do not calculate \n\n\n\nBposu,Hil09,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hil09>0.1\n\n (Liu et al. 2021). For the Hou09 and Hou16 methods, the corrected plane-of-sky uniform magnetic field strength is estimated as\n8\n\n\n\nBposu,Hou,est∼0.19μ0ρδvlos〈Bt2〉〈B02〉−12Hou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n9\n\n\n\nBpostot,Hou,est∼0.39μ0ρδvlos〈Bt2〉〈B2〉−12Hou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is the turbulent-to-ordered field strength ratio and \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)Hou\n\n is the turbulent-to-total field strength ratio derived from the two methods. Due to the limitation that the angular dispersion cannot exceed the value expected for a random field, the maximum derivable turbulent-to-ordered field strength ratio from the ADF methods is 0.76 (Liu et al. 2021). Thus, if the derived \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)Hou\n\n is greater than 0.76, the assumptions underlying the ADF methods on accounting for the line-of-sight signal integration may not be valid, which could lead to overestimation of the turbulent-to-ordered field strength ratio and underestimation of the field strength. In this situation, we adopt the turbulent-to-ordered field strength ratio \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou\n\n and the turbulent-to-total field strength ratio \n\n\n\n((〈Bt2〉\/〈B2〉)0.5)nosiHou\n\n without accounting for the line-of-sight signal integration and apply the same correction factors as those for the Hil09 method. Then the corrected plane-of-sky uniform magnetic field strength is estimated as\n10\n\n\n\nBposu,Hou,est∼0.1μ0ρδvlos(〈Bt2〉〈B02〉−12)nosiHou\n\nand the corrected plane-of-sky total magnetic field strength is estimated as\n11\n\n\n\nBpostot,Hou,est∼0.21μ0ρδvlos(〈Bt2〉〈B2〉−12)nosiHou,\n\nwhere \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou=((〈Bt2〉\/〈B02〉)0.5)Hou\/Nadf\n\n. N\nadf is the number of turbulent fluid elements along the line of sight. Similarly, we do not calculate \n\n\n\nBposu,Hou,est\n\n if \n\n\n\n((〈Bt2〉\/〈B02〉)0.5)nosiHou>0.1\n\n (Liu et al. 2021).","Citation Text":["Liu et al. 2021"],"Citation Start End":[[3112,3127]]} {"Identifier":"2021AandA...647A.177D__Mozunder_et_al._1968_Instance_1","Paragraph":"An estimate of a sputtering cross-section can be inferred from our measurements with σs ≈ V∕d, where V is the volume occupied by \n\n${Y}_{\\textrm{s}}^{\\infty}$Ys∞\n molecules and d the depth of sputtering. \n\n$\\sigma_{\\textrm{s}}\\approx {Y}_{\\textrm{s}}^{\\infty}\/l_{\\textrm{d}}\/\\textrm{ml}$σs≈Ys∞\/ld\/ml\n, where ml is the number of CO or CO2 molecules cm−2 in a monolayer (about 6.7 × 1014 cm−2 and 5.7 × 1014 cm−2, respectively,with the adopted ice densities). As is shown in Table 1, the sputtering radius rs would therefore be about 1.26 to 2.12 times larger than the radiolysis destruction radius rd in the case of the CO2 ice, and 2.03 to 2.36 for CO in the considered energy range (~0.5-1 MeV\/u). The net radiolysis is the combined effect of the direct primary excitations and ionisations, the core of the energy deposition by the ion, and the so-called delta rays (energetic secondary electrons) travelling at much larger distances from the core; that is, several hundreds of nanometres at the considered energies in this work (e.g. Mozunder et al. 1968; Magee & Chatterjee 1980; Katz et al. 1990; Moribayashi 2014; Awad & Abu-Shady 2020). The effective radiolysis track radius that we calculate is lower than the sputtering one, which points towards a large fraction of the energy deposited in the core of the track. The scatter on the ratio of these radii is due to the lack of more precise data. It nevertheless allows to put a rough constraint on the estimate of Nd in the absence of additional depth measurements, with \n\n${N}_{\\textrm{d}} \\lesssim {Y}_{\\textrm{s}}^{\\infty}\/\\sigma_{\\textrm{d}}$Nd≲Ys∞\/σd\n. If the rs∕rd ratio is high, a large amount of species come from the thermal sublimation of an ice spot less affected by radiolysis, and the fraction of ejected intact molecules is higher. The aspect ratio corresponding to these experiments evolves between about ten and twenty for CO2 and CO, whereas for water ice at a stopping power of Se ≈ 3.6 × 103eV∕1015 H2 O molecules cm−2, we show that it is closer to one (Dartois et al. 2018). The depth of sputtering is much larger for CO and CO2 than for H2O at the same energy deposition, not only because their sublimation rate is higher, but also because they do not form OH bonds. For complex organic molecules embedded in ice mantles dominated by a CO or CO2 ice matrix, with the lack of OH bonding and the sputtering for trace species being driven by that of the matrix (in the astrophysical context), the co-desorption of complex organic molecules present in low proportions with respect to CO\/CO2 cannot only be more efficient, but will thus arise from deeper layers.","Citation Text":["Mozunder et al. 1968"],"Citation Start End":[[1036,1056]]} {"Identifier":"2021AandA...647A.17Dartois_et_al._2018_Instance_1","Paragraph":"An estimate of a sputtering cross-section can be inferred from our measurements with σs ≈ V∕d, where V is the volume occupied by \n\n${Y}_{\\textrm{s}}^{\\infty}$Ys∞\n molecules and d the depth of sputtering. \n\n$\\sigma_{\\textrm{s}}\\approx {Y}_{\\textrm{s}}^{\\infty}\/l_{\\textrm{d}}\/\\textrm{ml}$σs≈Ys∞\/ld\/ml\n, where ml is the number of CO or CO2 molecules cm−2 in a monolayer (about 6.7 × 1014 cm−2 and 5.7 × 1014 cm−2, respectively,with the adopted ice densities). As is shown in Table 1, the sputtering radius rs would therefore be about 1.26 to 2.12 times larger than the radiolysis destruction radius rd in the case of the CO2 ice, and 2.03 to 2.36 for CO in the considered energy range (~0.5-1 MeV\/u). The net radiolysis is the combined effect of the direct primary excitations and ionisations, the core of the energy deposition by the ion, and the so-called delta rays (energetic secondary electrons) travelling at much larger distances from the core; that is, several hundreds of nanometres at the considered energies in this work (e.g. Mozunder et al. 1968; Magee & Chatterjee 1980; Katz et al. 1990; Moribayashi 2014; Awad & Abu-Shady 2020). The effective radiolysis track radius that we calculate is lower than the sputtering one, which points towards a large fraction of the energy deposited in the core of the track. The scatter on the ratio of these radii is due to the lack of more precise data. It nevertheless allows to put a rough constraint on the estimate of Nd in the absence of additional depth measurements, with \n\n${N}_{\\textrm{d}} \\lesssim {Y}_{\\textrm{s}}^{\\infty}\/\\sigma_{\\textrm{d}}$Nd≲Ys∞\/σd\n. If the rs∕rd ratio is high, a large amount of species come from the thermal sublimation of an ice spot less affected by radiolysis, and the fraction of ejected intact molecules is higher. The aspect ratio corresponding to these experiments evolves between about ten and twenty for CO2 and CO, whereas for water ice at a stopping power of Se ≈ 3.6 × 103eV∕1015 H2 O molecules cm−2, we show that it is closer to one (Dartois et al. 2018). The depth of sputtering is much larger for CO and CO2 than for H2O at the same energy deposition, not only because their sublimation rate is higher, but also because they do not form OH bonds. For complex organic molecules embedded in ice mantles dominated by a CO or CO2 ice matrix, with the lack of OH bonding and the sputtering for trace species being driven by that of the matrix (in the astrophysical context), the co-desorption of complex organic molecules present in low proportions with respect to CO\/CO2 cannot only be more efficient, but will thus arise from deeper layers.","Citation Text":["Dartois et al. 2018"],"Citation Start End":[[2029,2048]]} {"Identifier":"2018ApJ...860....8X__Liang_&_Zhang_2005_Instance_1","Paragraph":"For GRB 140629A, our analysis suggests that the optical and X-ray afterglows are from a narrow jet (\n\n\n\n\n\n rad) with a low B \n\n\n\n\n\n in a dense medium (n = 60 cm−3). In addition, the radiation efficiency of GRB 140629A is extremely low. We test whether or not it satisfies various empirical relations reported in the literature derived from observations of the prompt gamma-ray phase and the multi-wavelength afterglows. By estimating the jet opening angle with a jet-like break time tj in late multi-wavelength light curves, Ghirlanda et al. (2004a) derived a tight correlation between geometrically corrected jet energy \n\n\n\n\n\n and the peak energy \n\n\n\n\n\n of \n\n\n\n\n\n spectrum in the burst frame, i.e., \n\n\n\n\n\n. The \n\n\n\n\n\n value inferred from the Ghirlanda relation is 46 keV for GRB 140629A, which is definitely inconsistent with the data, i.e., \n\n\n\n\n\n. Liang & Zhang (2005) derived an empirical relation between \n\n\n\n\n\n, \n\n\n\n\n\n, and the jet break time (\n\n\n\n\n\n) in the burst frame, i.e., \n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\nBased on this relation, an isotropic energy \n\n\n\n\n\n erg is obtained, which is larger than that observed by more than one order of magnitude. These results suggest that GRB 140629A does not follow these two relations (Ghirlanda et al. 2004a; Liang & Zhang 2005), although both tight correlations have been used for measuring the cosmological parameters with GRBs (e.g., Dai et al. 2004; Ghirlanda et al. 2004b; Liang & Zhang 2005; Wang et al. 2015a). Note that the observed jet break time of GRB 140629A is much earlier, hence the inferred θj is much lower than those of the GRBs used to derive these relations (e.g., Frail et al. 2001; Bloom et al. 2003). It is unclear whether the violation of GRB 140629A is due to the selection effect or other physical reasons. For example, two-component jet models composed of a narrow and a wide component have been proposed to explain the data of some GRBs (e.g., Huang et al. 2004; Racusin et al. 2008). In these cases, the high-energy emission was proposed to be emitted by the narrow jet. However, one cannot exclude the possibility that the observed gamma-ray energy would be dominated by the wide jet component under certain conditions. Meanwhile, the early break time for GRB 140629A is likely due to the effect of the narrow jet component but not the wide one. If this is the case, the inconsistency between the jet energy and the opening angle would result in this violation of GRB 140629A. Liang et al. (2015) discovered a tight empirical correlation between Liso, \n\n\n\n\n\n, and Γ0 to reveal the direct connection between the gamma-ray and afterglows,\n7\n\n\n\n\n\nBased on the equation above, we get \n\n\n\n\n\n for GRB 140629A, where the error is calculated from the uncertainties in \n\n\n\n\n\n and Γ0 only. The derived \n\n\n\n\n\n is well consistent with the observed one, \n\n\n\n\n\n erg s−1, as shown in Figure 6. Note that the initial Lorentz factor of the ejecta Γ0 is sensitive to the deceleration time (the peak time of the onset bump), but not strongly related to the jet break time. The onset of the afterglow bump is usually bright (Liang et al. 2010, 2013; Li et al. 2012; Wang et al. 2013), and it is easier to identify than the jet break time from an observed light curve.10\n\n10\nThe jet break is usually detected in late optical afterglow light curves. It is dim and also contaminated by emission from the host galaxy and\/or associated supernovae (e.g., Li et al. 2012). This is also an issue in identifying an observed jet break as the narrow or the wide component in the case of a two-component jet.\n The consistency of GRB 140629A with \n\n\n\n\n\n suggests that this relation is more robust than the Ghirlanda or Liang–Zhang relations, since it is not sensitive to the jet opening angle θj.","Citation Text":["Liang & Zhang (2005)"],"Citation Start End":[[851,871]]} {"Identifier":"2018ApJ...860....8X__Liang_&_Zhang_2005_Instance_2","Paragraph":"For GRB 140629A, our analysis suggests that the optical and X-ray afterglows are from a narrow jet (\n\n\n\n\n\n rad) with a low B \n\n\n\n\n\n in a dense medium (n = 60 cm−3). In addition, the radiation efficiency of GRB 140629A is extremely low. We test whether or not it satisfies various empirical relations reported in the literature derived from observations of the prompt gamma-ray phase and the multi-wavelength afterglows. By estimating the jet opening angle with a jet-like break time tj in late multi-wavelength light curves, Ghirlanda et al. (2004a) derived a tight correlation between geometrically corrected jet energy \n\n\n\n\n\n and the peak energy \n\n\n\n\n\n of \n\n\n\n\n\n spectrum in the burst frame, i.e., \n\n\n\n\n\n. The \n\n\n\n\n\n value inferred from the Ghirlanda relation is 46 keV for GRB 140629A, which is definitely inconsistent with the data, i.e., \n\n\n\n\n\n. Liang & Zhang (2005) derived an empirical relation between \n\n\n\n\n\n, \n\n\n\n\n\n, and the jet break time (\n\n\n\n\n\n) in the burst frame, i.e., \n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\nBased on this relation, an isotropic energy \n\n\n\n\n\n erg is obtained, which is larger than that observed by more than one order of magnitude. These results suggest that GRB 140629A does not follow these two relations (Ghirlanda et al. 2004a; Liang & Zhang 2005), although both tight correlations have been used for measuring the cosmological parameters with GRBs (e.g., Dai et al. 2004; Ghirlanda et al. 2004b; Liang & Zhang 2005; Wang et al. 2015a). Note that the observed jet break time of GRB 140629A is much earlier, hence the inferred θj is much lower than those of the GRBs used to derive these relations (e.g., Frail et al. 2001; Bloom et al. 2003). It is unclear whether the violation of GRB 140629A is due to the selection effect or other physical reasons. For example, two-component jet models composed of a narrow and a wide component have been proposed to explain the data of some GRBs (e.g., Huang et al. 2004; Racusin et al. 2008). In these cases, the high-energy emission was proposed to be emitted by the narrow jet. However, one cannot exclude the possibility that the observed gamma-ray energy would be dominated by the wide jet component under certain conditions. Meanwhile, the early break time for GRB 140629A is likely due to the effect of the narrow jet component but not the wide one. If this is the case, the inconsistency between the jet energy and the opening angle would result in this violation of GRB 140629A. Liang et al. (2015) discovered a tight empirical correlation between Liso, \n\n\n\n\n\n, and Γ0 to reveal the direct connection between the gamma-ray and afterglows,\n7\n\n\n\n\n\nBased on the equation above, we get \n\n\n\n\n\n for GRB 140629A, where the error is calculated from the uncertainties in \n\n\n\n\n\n and Γ0 only. The derived \n\n\n\n\n\n is well consistent with the observed one, \n\n\n\n\n\n erg s−1, as shown in Figure 6. Note that the initial Lorentz factor of the ejecta Γ0 is sensitive to the deceleration time (the peak time of the onset bump), but not strongly related to the jet break time. The onset of the afterglow bump is usually bright (Liang et al. 2010, 2013; Li et al. 2012; Wang et al. 2013), and it is easier to identify than the jet break time from an observed light curve.10\n\n10\nThe jet break is usually detected in late optical afterglow light curves. It is dim and also contaminated by emission from the host galaxy and\/or associated supernovae (e.g., Li et al. 2012). This is also an issue in identifying an observed jet break as the narrow or the wide component in the case of a two-component jet.\n The consistency of GRB 140629A with \n\n\n\n\n\n suggests that this relation is more robust than the Ghirlanda or Liang–Zhang relations, since it is not sensitive to the jet opening angle θj.","Citation Text":["Liang & Zhang 2005"],"Citation Start End":[[1251,1269]]} {"Identifier":"2017ApJ...836...65M___2014_Instance_2","Paragraph":"Bolometric magnitudes, \n\n\n\n\n\n, are estimated as the sum of the \n\n\n\n\n\n-band magnitudes, \n\n\n\n\n\n, bolometric correction (\n\n\n\n\n\n), and DMs, i.e., \n\n\n\n\n\n = \n\n\n\n\n\n−\n\n\n\n\n\n+\n\n\n\n\n\n-DM. \n\n\n\n\n\n are adopted from the work of Levesque et al. (2005), which is based on MARCS models. The new temperature scale by Davies et al. (2013) agrees within ±100 K with that of Levesque et al. (2005). Errors in the \n\n\n\n\n\n values are calculated by propagation. \n\n\n\n\n\n magnitude errors are provided in the 2MASS catalog (0.02 mag in average); errors in \n\n\n\n\n\n are described in Section 3.2 (0.02 mag on average); errors in \n\n\n\n\n\n are conservatively assumed to be 0.5 mag—the difference between the \n\n\n\n\n\n values provided by Levesque et al. (2005) for an M0Iab and M2Iab star amounts to ≈0.1 mag, while the typical difference between their \n\n\n\n\n\n values is 0.5 mag (e.g., Verhoelst et al. 2009); rare supergiant Ia can be more than 1 mag brighter. Adopted distance moduli, DMs, are those of Messineo et al. (2016), who estimated distances of 68 (out of 94) targets using extinction as indicator of distance, and calibrating the extinction–distance relation with clump stars surrounding the target (see also Drimmel et al. 2003; Messineo et al. 2014). Errors in the DM values range from 0.12 to 0.36 mag; they have been estimated as a sum of three terms: the uncertainty of the absolute magnitude of clump stars (≈0.11 mag), the error of the centroid of the Gaussian (0.04–0.25 mag, \n\n\n\n\n\n of the Gaussian divided by the square-root of the number of enclosed stars), and the uncertainty in the reddening of clump stars (\n\n\n\n\n\n ≈ 0.06 mag, taken as the half-width of the J − K bin times 0.537); only CMDs with a well visible trace were considered. To verify these bolometric magnitudes, which are based only on one magnitude (\n\n\n\n\n\n) plus the bolometric corrections by Levesque et al. (2005), we calculated estimates of bolometric magnitudes (\n\n\n\n\n\n) by directly integrating under their stellar energy distribution with the collected infrared measurements (see also Ortiz et al. 2002; Messineo et al. 2004, 2014). We extrapolated to zero the flux on the blue part (from 0 to 1.2 μm) of the spectrum with a blackbody, and to the red part (beyond 12–25 μm) with a linear fit passing through the last two available flux measurements. The differences between the two estimates of bolometric magnitudes yield an average of 0.09 mag with a σ = 0.03 mag. We obtained that the red extrapolation contributed only −0.004 to 0.002 mag to the total \n\n\n\n\n\n; the blue extrapolation added −0.85 mag (for the direct integration only JHKs magnitudes were used and not the DENIS I magnitudes). When including the DENIS I magnitudes, i.e., blue from 0 to 0.8 μm and green from 0.8 to 12–25 μm, we obtained that the contribution of the blue extrapolation to the total \n\n\n\n\n\n would drop to −0.18 mag—extinction in the I-band \n\n\n\n\n\n is assumed to be 6.8 times \n\n\n\n\n\n(Messineo et al. 2005). Table 7 lists the inferred values of \n\n\n\n\n\n, bolometric magnitudes, and adopted DM values.","Citation Text":["Messineo et al.","2014"],"Citation Start End":[[2054,2069],[2076,2080]]} {"Identifier":"2017ApJ...836...65M___2014_Instance_1","Paragraph":"Bolometric magnitudes, \n\n\n\n\n\n, are estimated as the sum of the \n\n\n\n\n\n-band magnitudes, \n\n\n\n\n\n, bolometric correction (\n\n\n\n\n\n), and DMs, i.e., \n\n\n\n\n\n = \n\n\n\n\n\n−\n\n\n\n\n\n+\n\n\n\n\n\n-DM. \n\n\n\n\n\n are adopted from the work of Levesque et al. (2005), which is based on MARCS models. The new temperature scale by Davies et al. (2013) agrees within ±100 K with that of Levesque et al. (2005). Errors in the \n\n\n\n\n\n values are calculated by propagation. \n\n\n\n\n\n magnitude errors are provided in the 2MASS catalog (0.02 mag in average); errors in \n\n\n\n\n\n are described in Section 3.2 (0.02 mag on average); errors in \n\n\n\n\n\n are conservatively assumed to be 0.5 mag—the difference between the \n\n\n\n\n\n values provided by Levesque et al. (2005) for an M0Iab and M2Iab star amounts to ≈0.1 mag, while the typical difference between their \n\n\n\n\n\n values is 0.5 mag (e.g., Verhoelst et al. 2009); rare supergiant Ia can be more than 1 mag brighter. Adopted distance moduli, DMs, are those of Messineo et al. (2016), who estimated distances of 68 (out of 94) targets using extinction as indicator of distance, and calibrating the extinction–distance relation with clump stars surrounding the target (see also Drimmel et al. 2003; Messineo et al. 2014). Errors in the DM values range from 0.12 to 0.36 mag; they have been estimated as a sum of three terms: the uncertainty of the absolute magnitude of clump stars (≈0.11 mag), the error of the centroid of the Gaussian (0.04–0.25 mag, \n\n\n\n\n\n of the Gaussian divided by the square-root of the number of enclosed stars), and the uncertainty in the reddening of clump stars (\n\n\n\n\n\n ≈ 0.06 mag, taken as the half-width of the J − K bin times 0.537); only CMDs with a well visible trace were considered. To verify these bolometric magnitudes, which are based only on one magnitude (\n\n\n\n\n\n) plus the bolometric corrections by Levesque et al. (2005), we calculated estimates of bolometric magnitudes (\n\n\n\n\n\n) by directly integrating under their stellar energy distribution with the collected infrared measurements (see also Ortiz et al. 2002; Messineo et al. 2004, 2014). We extrapolated to zero the flux on the blue part (from 0 to 1.2 μm) of the spectrum with a blackbody, and to the red part (beyond 12–25 μm) with a linear fit passing through the last two available flux measurements. The differences between the two estimates of bolometric magnitudes yield an average of 0.09 mag with a σ = 0.03 mag. We obtained that the red extrapolation contributed only −0.004 to 0.002 mag to the total \n\n\n\n\n\n; the blue extrapolation added −0.85 mag (for the direct integration only JHKs magnitudes were used and not the DENIS I magnitudes). When including the DENIS I magnitudes, i.e., blue from 0 to 0.8 μm and green from 0.8 to 12–25 μm, we obtained that the contribution of the blue extrapolation to the total \n\n\n\n\n\n would drop to −0.18 mag—extinction in the I-band \n\n\n\n\n\n is assumed to be 6.8 times \n\n\n\n\n\n(Messineo et al. 2005). Table 7 lists the inferred values of \n\n\n\n\n\n, bolometric magnitudes, and adopted DM values.","Citation Text":["Messineo et al. 2014"],"Citation Start End":[[1199,1219]]} {"Identifier":"2019ApJ...876...53J__Côté_et_al._2007_Instance_1","Paragraph":"The Virgo, however, remains the only cluster in which intracluster X-ray sources have been probed and detected. The Chandra observations utilized by Hou et al. (2017) covered only a small portion (∼3 deg2) of Virgo, but its large angular size (∼100 deg2) renders a full mapping a challenging, if not infeasible, task with contemporary X-ray telescopes, thus limiting our ability to extend the search for intracluster X-ray sources in Virgo. Located at a distance of ∼20.0 Mpc (Blakeslee et al. 2009), the Fornax cluster is a dynamically more evolved, more compact and less massive system compared to Virgo. Like Virgo, Fornax has been an important laboratory to explore the physics of hierarchical structure growth. Recent optical surveys including the Hubble Space Telescope ACS Fornax Cluster Survey (ACSFCS; Jordán et al. 2007) and the Fornax Deep Survey with VST (FDS; Iodice et al. 2016) have significantly advanced our knowledge about the ETGs (Côté et al. 2007; Turner et al. 2012), dwarf galaxies (Venhola et al. 2017), GC populations (Jordán et al. 2015), as well as the ICL (Iodice et al. 2017) of this cluster. In the X-ray band, a survey of the inner ∼30′ region of Fornax has been conducted with Chandra observations (Scharf et al. 2005), which resulted in the detection of more than 700 point-like sources (including CXB sources) against an extended, asymmetric diffuse X-ray emission from the intracluster medium (Ikebe et al. 1996; Jones et al. 1997). The X-ray sources in the BCG, NGC 1399, have been extensively studied with a focus on their connection with GCs (Angelini et al. 2001; Paolillo et al. 2011; D’Ago et al. 2014). The X-ray sources located outside the main stellar content of NGC 1399, however, have received little attention so far, except for the work of Phillipps et al. (2013), which studied the incidence rate of X-ray sources in compact stellar systems, including GCs and the so-called ultra-compact dwarfs (UCDs; Phillipps et al. 2001).","Citation Text":["Côté et al. 2007"],"Citation Start End":[[951,967]]} {"Identifier":"2019ApJ...876...53JAngelini_et_al._2001_Instance_1","Paragraph":"The Virgo, however, remains the only cluster in which intracluster X-ray sources have been probed and detected. The Chandra observations utilized by Hou et al. (2017) covered only a small portion (∼3 deg2) of Virgo, but its large angular size (∼100 deg2) renders a full mapping a challenging, if not infeasible, task with contemporary X-ray telescopes, thus limiting our ability to extend the search for intracluster X-ray sources in Virgo. Located at a distance of ∼20.0 Mpc (Blakeslee et al. 2009), the Fornax cluster is a dynamically more evolved, more compact and less massive system compared to Virgo. Like Virgo, Fornax has been an important laboratory to explore the physics of hierarchical structure growth. Recent optical surveys including the Hubble Space Telescope ACS Fornax Cluster Survey (ACSFCS; Jordán et al. 2007) and the Fornax Deep Survey with VST (FDS; Iodice et al. 2016) have significantly advanced our knowledge about the ETGs (Côté et al. 2007; Turner et al. 2012), dwarf galaxies (Venhola et al. 2017), GC populations (Jordán et al. 2015), as well as the ICL (Iodice et al. 2017) of this cluster. In the X-ray band, a survey of the inner ∼30′ region of Fornax has been conducted with Chandra observations (Scharf et al. 2005), which resulted in the detection of more than 700 point-like sources (including CXB sources) against an extended, asymmetric diffuse X-ray emission from the intracluster medium (Ikebe et al. 1996; Jones et al. 1997). The X-ray sources in the BCG, NGC 1399, have been extensively studied with a focus on their connection with GCs (Angelini et al. 2001; Paolillo et al. 2011; D’Ago et al. 2014). The X-ray sources located outside the main stellar content of NGC 1399, however, have received little attention so far, except for the work of Phillipps et al. (2013), which studied the incidence rate of X-ray sources in compact stellar systems, including GCs and the so-called ultra-compact dwarfs (UCDs; Phillipps et al. 2001).","Citation Text":["Angelini et al. 2001"],"Citation Start End":[[1581,1601]]} {"Identifier":"2019ApJ...876...53JBlakeslee_et_al._2009_Instance_1","Paragraph":"The Virgo, however, remains the only cluster in which intracluster X-ray sources have been probed and detected. The Chandra observations utilized by Hou et al. (2017) covered only a small portion (∼3 deg2) of Virgo, but its large angular size (∼100 deg2) renders a full mapping a challenging, if not infeasible, task with contemporary X-ray telescopes, thus limiting our ability to extend the search for intracluster X-ray sources in Virgo. Located at a distance of ∼20.0 Mpc (Blakeslee et al. 2009), the Fornax cluster is a dynamically more evolved, more compact and less massive system compared to Virgo. Like Virgo, Fornax has been an important laboratory to explore the physics of hierarchical structure growth. Recent optical surveys including the Hubble Space Telescope ACS Fornax Cluster Survey (ACSFCS; Jordán et al. 2007) and the Fornax Deep Survey with VST (FDS; Iodice et al. 2016) have significantly advanced our knowledge about the ETGs (Côté et al. 2007; Turner et al. 2012), dwarf galaxies (Venhola et al. 2017), GC populations (Jordán et al. 2015), as well as the ICL (Iodice et al. 2017) of this cluster. In the X-ray band, a survey of the inner ∼30′ region of Fornax has been conducted with Chandra observations (Scharf et al. 2005), which resulted in the detection of more than 700 point-like sources (including CXB sources) against an extended, asymmetric diffuse X-ray emission from the intracluster medium (Ikebe et al. 1996; Jones et al. 1997). The X-ray sources in the BCG, NGC 1399, have been extensively studied with a focus on their connection with GCs (Angelini et al. 2001; Paolillo et al. 2011; D’Ago et al. 2014). The X-ray sources located outside the main stellar content of NGC 1399, however, have received little attention so far, except for the work of Phillipps et al. (2013), which studied the incidence rate of X-ray sources in compact stellar systems, including GCs and the so-called ultra-compact dwarfs (UCDs; Phillipps et al. 2001).","Citation Text":["Blakeslee et al. 2009"],"Citation Start End":[[477,498]]} {"Identifier":"2019MNRAS.485..440P__Lazendic_et_al._2006_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Lazendic et al. 2006"],"Citation Start End":[[842,862]]} {"Identifier":"2019MNRAS.485..440PHwang_&_Laming_2009_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Hwang & Laming 2009"],"Citation Start End":[[527,546]]} {"Identifier":"2019MNRAS.485..440PDeLaney_et_al._2004_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["DeLaney et al. 2004"],"Citation Start End":[[633,652]]} {"Identifier":"2019MNRAS.485..440PChevalier_&_Kirshner_1979_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Chevalier & Kirshner 1979"],"Citation Start End":[[974,999]]} {"Identifier":"2019MNRAS.485..440PDeLaney_et_al._2010_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["DeLaney et al. 2010"],"Citation Start End":[[1175,1194]]} {"Identifier":"2019MNRAS.485..440PDeLaney_et_al._2010_Instance_2","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["DeLaney et al. 2010"],"Citation Start End":[[1395,1414]]} {"Identifier":"2019MNRAS.485..440PRaymond_et_al._(2018)_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Raymond et al. (2018)"],"Citation Start End":[[1963,1984]]} {"Identifier":"2019MNRAS.485..440PArendt_et_al._1999_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Arendt et al. 1999"],"Citation Start End":[[1258,1276]]} {"Identifier":"2019MNRAS.485..440PArendt_et_al._1999_Instance_2","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Arendt et al. 1999"],"Citation Start End":[[1493,1511]]} {"Identifier":"2019MNRAS.485..440PSmith_et_al._(2009)_Instance_1","Paragraph":"In order to determine the dust emission from the remnant, several physical properties are required: the densities and temperatures of the electrons and nuclei, the dominant type of nucleus, and the radiation field strength and spectrum. Observations of Cas A reveal a complex structure, with material covering a wide range of densities and temperatures emitting at different wavelengths. The supernova explosion has driven a forward shock into the circumstellar material, thought to be from the stellar wind of the progenitor (Hwang & Laming 2009), while the ejecta from the supernova itself crosses the reverse shock as it expands (DeLaney et al. 2004). Both shocks are visible as X-ray emitting regions, with typical densities of $n \\sim 1{\\text{-}}10 \\, {\\rm cm}^{-3}$ and temperatures $T \\gtrsim 10^7 \\, {\\rm K}$ (Willingale et al. 2003; Lazendic et al. 2006; Patnaude & Fesen 2014; Wang & Li 2016). The ejecta is mostly comprised of heavy elements, principally oxygen (Chevalier & Kirshner 1979; Willingale et al. 2003). As well as the X-ray emitting gas, the shocked ejecta also consists of denser clumps or knots, emitting in the optical and IR (Hurford & Fesen 1996; DeLaney et al. 2010; Patnaude & Fesen 2014) and associated with the dust emission (Arendt et al. 1999). Electron densities in the shocked clumps are $n_{\\rm e}\\sim 10^3{\\text{-}}10^5\\, {\\rm cm}^{-3}$ (Smith et al. 2009; DeLaney et al. 2010; Lee et al. 2017), while the gas temperatures are of order $10^4 \\, {\\rm K}$ (Arendt et al. 1999; Docenko & Sunyaev 2010). The SNR also contains ejecta that has not yet encountered the reverse shock and is consequently much cooler. Smith et al. (2009) estimated a maximum electron density of $n_{\\rm e}\\lesssim 100 \\, {\\rm cm}^{-3}$ for the unshocked ejecta based on forbidden line ratios, while observations of radio absorption by DeLaney et al. (2014) and Arias et al. (2018) give $n_{\\rm e}\\sim 10 \\, {\\rm cm}^{-3}$ and $T \\sim 100 \\, {\\rm K}$. Raymond et al. (2018) inferred a pre-shock temperature of ${\\sim } 100 \\, {\\rm K}$ from [Si i] IR emission lines.","Citation Text":["Smith et al. (2009)"],"Citation Start End":[[1647,1666]]} {"Identifier":"2016MNRAS.463..512D__Lilje_&_Lahav_1991_Instance_1","Paragraph":"The spherical evolution model was originally introduced to model the evolution of overdensities (Gunn & Gott 1972). This model assumes a spherical underdensity ρi embedded in an expanding, homogeneous background with density $\\bar{\\rho }$. The evolution of each radius is determined by the total mass M contained within the proper radius R via the acceleration equation in the Newtonian regime.1 The model makes no assumption about the background cosmology with the evolution given as\n\n(1)\n\n\\begin{equation}\n\\frac{\\ddot{R}}{R} = \\frac{-4\\pi G}{3} \\sum _{n}(\\rho _n + 3p_n),\n\\end{equation}\n\nwhere R is the proper radius, the double dot indicates the second derivative with respect to proper time t, G is the gravitational constant, and ρn and pn are the density and pressure components, respectively, of any contributing component i.e., radiation, matter, dark energy (Padmanabhan 1996). The same equation, known as the Friedmann equation, applies to an unperturbed region, which yields the expansion history of the universe. The spherical model has been applied to solve the evolution of overdensities and underdensities (e.g. Gunn & Gott 1972; Peebles 1980; Lilje & Lahav 1991; Sheth & van de Weygaert 2004). Using the spherical model, the evolution equation in a Λ = 0 universe becomes\n\n(2)\n\n\\begin{equation}\n\\ddot{R} = -\\frac{GM}{R^2}.\n\\end{equation}\n\nTo solve the above equation, the initial density and velocity profiles are needed. For the case of an overdensity, which eventually collapses and virializes as a halo, the initial density profile is usually taken to be a spherical top-hat and the initial velocity is assumed to be the Hubble flow at the initial time ti. We will use the subscript i to indicate quantities at the initial time throughout the paper. With these assumptions, the equation can be solved analytically and the solution for the size of the radius as a function of time takes the following parametric form (Gunn & Gott 1972; Lilje & Lahav 1991):\n\n(3)\n\n\\begin{eqnarray}\nR &=& A(1-\\cos \\theta ), \\nonumber \\\\\nt+T &=& B(\\theta - \\sin \\theta ), \\nonumber \\\\\nA^3 &=& GMB^2,\n\\end{eqnarray}\n\nwhere A, B, and T are constants that can be fixed once the initial conditions are fixed and θ is an indicator of time. For voids with the same initial settings, the analytical solutions can also be found by taking an inverse top-hat model for the density profile (Gunn & Gott 1972; Peebles 1980; Lilje & Lahav 1991; Sheth & van de Weygaert 2004):\n\n(4)\n\n\\begin{eqnarray}\nR &=& A(\\cosh \\theta -1), \\nonumber \\\\\nt+T &=& B(\\sinh \\theta -\\theta ), \\nonumber \\\\\nA^3 &=& GMB^2.\n\\end{eqnarray}\n\nNote that the parametric solutions above apply to any Λ = 0 universe. For this study we use the flat EdS cosmology.","Citation Text":["Lilje & Lahav 1991"],"Citation Start End":[[1159,1177]]} {"Identifier":"2016MNRAS.463..512D__Lilje_&_Lahav_1991_Instance_2","Paragraph":"The spherical evolution model was originally introduced to model the evolution of overdensities (Gunn & Gott 1972). This model assumes a spherical underdensity ρi embedded in an expanding, homogeneous background with density $\\bar{\\rho }$. The evolution of each radius is determined by the total mass M contained within the proper radius R via the acceleration equation in the Newtonian regime.1 The model makes no assumption about the background cosmology with the evolution given as\n\n(1)\n\n\\begin{equation}\n\\frac{\\ddot{R}}{R} = \\frac{-4\\pi G}{3} \\sum _{n}(\\rho _n + 3p_n),\n\\end{equation}\n\nwhere R is the proper radius, the double dot indicates the second derivative with respect to proper time t, G is the gravitational constant, and ρn and pn are the density and pressure components, respectively, of any contributing component i.e., radiation, matter, dark energy (Padmanabhan 1996). The same equation, known as the Friedmann equation, applies to an unperturbed region, which yields the expansion history of the universe. The spherical model has been applied to solve the evolution of overdensities and underdensities (e.g. Gunn & Gott 1972; Peebles 1980; Lilje & Lahav 1991; Sheth & van de Weygaert 2004). Using the spherical model, the evolution equation in a Λ = 0 universe becomes\n\n(2)\n\n\\begin{equation}\n\\ddot{R} = -\\frac{GM}{R^2}.\n\\end{equation}\n\nTo solve the above equation, the initial density and velocity profiles are needed. For the case of an overdensity, which eventually collapses and virializes as a halo, the initial density profile is usually taken to be a spherical top-hat and the initial velocity is assumed to be the Hubble flow at the initial time ti. We will use the subscript i to indicate quantities at the initial time throughout the paper. With these assumptions, the equation can be solved analytically and the solution for the size of the radius as a function of time takes the following parametric form (Gunn & Gott 1972; Lilje & Lahav 1991):\n\n(3)\n\n\\begin{eqnarray}\nR &=& A(1-\\cos \\theta ), \\nonumber \\\\\nt+T &=& B(\\theta - \\sin \\theta ), \\nonumber \\\\\nA^3 &=& GMB^2,\n\\end{eqnarray}\n\nwhere A, B, and T are constants that can be fixed once the initial conditions are fixed and θ is an indicator of time. For voids with the same initial settings, the analytical solutions can also be found by taking an inverse top-hat model for the density profile (Gunn & Gott 1972; Peebles 1980; Lilje & Lahav 1991; Sheth & van de Weygaert 2004):\n\n(4)\n\n\\begin{eqnarray}\nR &=& A(\\cosh \\theta -1), \\nonumber \\\\\nt+T &=& B(\\sinh \\theta -\\theta ), \\nonumber \\\\\nA^3 &=& GMB^2.\n\\end{eqnarray}\n\nNote that the parametric solutions above apply to any Λ = 0 universe. For this study we use the flat EdS cosmology.","Citation Text":["Lilje & Lahav 1991"],"Citation Start End":[[1954,1972]]} {"Identifier":"2016MNRAS.463..512D__Lilje_&_Lahav_1991_Instance_3","Paragraph":"The spherical evolution model was originally introduced to model the evolution of overdensities (Gunn & Gott 1972). This model assumes a spherical underdensity ρi embedded in an expanding, homogeneous background with density $\\bar{\\rho }$. The evolution of each radius is determined by the total mass M contained within the proper radius R via the acceleration equation in the Newtonian regime.1 The model makes no assumption about the background cosmology with the evolution given as\n\n(1)\n\n\\begin{equation}\n\\frac{\\ddot{R}}{R} = \\frac{-4\\pi G}{3} \\sum _{n}(\\rho _n + 3p_n),\n\\end{equation}\n\nwhere R is the proper radius, the double dot indicates the second derivative with respect to proper time t, G is the gravitational constant, and ρn and pn are the density and pressure components, respectively, of any contributing component i.e., radiation, matter, dark energy (Padmanabhan 1996). The same equation, known as the Friedmann equation, applies to an unperturbed region, which yields the expansion history of the universe. The spherical model has been applied to solve the evolution of overdensities and underdensities (e.g. Gunn & Gott 1972; Peebles 1980; Lilje & Lahav 1991; Sheth & van de Weygaert 2004). Using the spherical model, the evolution equation in a Λ = 0 universe becomes\n\n(2)\n\n\\begin{equation}\n\\ddot{R} = -\\frac{GM}{R^2}.\n\\end{equation}\n\nTo solve the above equation, the initial density and velocity profiles are needed. For the case of an overdensity, which eventually collapses and virializes as a halo, the initial density profile is usually taken to be a spherical top-hat and the initial velocity is assumed to be the Hubble flow at the initial time ti. We will use the subscript i to indicate quantities at the initial time throughout the paper. With these assumptions, the equation can be solved analytically and the solution for the size of the radius as a function of time takes the following parametric form (Gunn & Gott 1972; Lilje & Lahav 1991):\n\n(3)\n\n\\begin{eqnarray}\nR &=& A(1-\\cos \\theta ), \\nonumber \\\\\nt+T &=& B(\\theta - \\sin \\theta ), \\nonumber \\\\\nA^3 &=& GMB^2,\n\\end{eqnarray}\n\nwhere A, B, and T are constants that can be fixed once the initial conditions are fixed and θ is an indicator of time. For voids with the same initial settings, the analytical solutions can also be found by taking an inverse top-hat model for the density profile (Gunn & Gott 1972; Peebles 1980; Lilje & Lahav 1991; Sheth & van de Weygaert 2004):\n\n(4)\n\n\\begin{eqnarray}\nR &=& A(\\cosh \\theta -1), \\nonumber \\\\\nt+T &=& B(\\sinh \\theta -\\theta ), \\nonumber \\\\\nA^3 &=& GMB^2.\n\\end{eqnarray}\n\nNote that the parametric solutions above apply to any Λ = 0 universe. For this study we use the flat EdS cosmology.","Citation Text":["Lilje & Lahav 1991"],"Citation Start End":[[2434,2452]]} {"Identifier":"2022ApJ...935L...1L__Rybicki_&_Lightman_1986_Instance_1","Paragraph":"Figure 4 shows the cooling rate of the plasma due to emission (\n\n\n\nλem=ρκemaradTe4\n\n) and inverse-Compton scattering (λ\nsc = ρ\nκ\nes\nE\nrad 4k\n\nb\n\nT\n\ne\n\/m\n\ne\n\nc\n2), in addition to the heating rate through absorption (λ\nabs = ρ\nκ\nabs\nE\nrad). As can be seen, the cooling is predominantly concentrated near the equatorial plane which has an optical depth of order unity (τ\nes ∼ 1). Because the Compton scattering rate exceeds the emission rate, it is conceivable that most radiation actually gets Compton upscattered before leaving the corona. We estimate that the Compton-y parameter (y = τ\nes 4k\n\nb\n\nT\n\ne\n\/m\n\ne\n\nc\n2), which measures the average fractional energy gain of photons due to Comptonization (e.g., Rybicki & Lightman 1986), can easily exceed y ≳ 1 in the T\n\ne\n ≳ 5 × 108 K plasma near the midplane of the corona. Pinpointing the exact value of the Compton y parameter is nontrivial because absorption will play an important role in some optically thick patches near the midplane. A more detailed calculation that takes into account emission, absorption, and scattering in the plasma along photon geodesics will be required to further constrain the Compton-y parameter. Nevertheless, this work suggests that the corona will upscatter and significantly harden thermal radiation from the disk and cyclosynchrotron emission from the corona (see also Dexter et al. 2021; Scepi et al. 2021). In contrast, the bottom row in Figure 3 shows that in RADTOR, the ions and electrons are strongly coupled in the cold disk, which remains optically thick to both scattering and absorption. Because this disk extends all the way to the event horizon, we expect a strong thermal emission component in the emergent spectrum. Compton upscattering of disk photons by the winds sandwiching the inner disk to temperatures necessary to significantly harden the spectrum is not expected because these winds are predominantly cold (T\n\ne\n ≲ 5 × 107 K). The hot pockets of gas with temperatures T\n\ne\n ≳ 108 K within r ≲ 5r\n\ng\n in Figure 3 are relatively rare and seem to be more prominent at later times when the disk becomes numerically underresolved due to thermal collapse (Appendix A.2).","Citation Text":["Rybicki & Lightman 1986"],"Citation Start End":[[705,728]]} {"Identifier":"2020ApJ...903....6M__Megha_et_al._2019_Instance_1","Paragraph":"In this paper, we consider resonance scattering on a two-level atom with an infinitely sharp and unpolarized lower level. As for the frequency redistribution, we consider both CRD and angle-averaged PRD. In an unmagnetized one-dimensional spherically symmetric atmosphere, the polarized radiation field is axially symmetric and is described by \n\n\n\n\n\n. We also take into account the effects of radial velocity fields. We solve the concerned transfer equation in the CMF and in the nonrelativistic regime of velocity fields. To efficiently handle the sphericity effects, we solve the spherical transfer equation in the (p, z) coordinate system (Hummer & Rybicki 1971), which is also called the tangent-ray method. Here z is the distance along the tangent rays and p is impact parameter (see Figure 1 in Megha et al. 2019). Following Frisch (2007), we express the Stokes vector components in terms of their irreducible components. From here on we present all the basic equations in the irreducible basis (see Sampoorna & Trujillo Bueno 2010 for details). The CMF polarized PRD transfer equation for a spherically symmetric medium in (p, z) representation under the nonrelativistic limit is given by (see also Equation (17) of Megha et al. 2019)\n1\n\n\n\n\n\nwhere x denotes the nondimensional frequency and \n\n\n\n\n\n denotes the irreducible Stokes vector with “+” and “−” referring to the outgoing and incoming rays, respectively. The radial optical depth is defined as dτr = −χl(r)dr, where r is the radial distance and χl(r) is the line averaged absorption coefficient. In the CMF the monochromatic optical depth along the tangent ray is given by dτ = [φ(x) + βc]dτr\/μ, where φ(x) is the line absorption profile function and βc = χc(r)\/χl(r) with χc(r) denoting the continuum absorption coefficient. The direction cosine of the tangent ray about the radius vector of the intercepting radial shell is given by \n\n\n\n\n\n. In Equation (1), \n\n\n\n\n\n denotes the CMF term, which has the form\n2\n\n\n\n\n\nwhere χ(r, x) = χl(r)φ(x) + χc(r), and\n3\n\n\n\n\n\nThe symbol V denotes the ratio of radial (vr) to the thermal (\n\n\n\n\n\n) velocities. In Equation (1), \n\n\n\n\n\n represents the irreducible CMF total source vector and is given by\n4\n\n\n\n\n\nwhere the line source vector is of the form\n5\n\n\n\n\n\nHere ϵ gives the probability of destruction of photons by inelastic collisions, Bν0 is the Planck function at the line center frequency ν0, and \n\n\n\n\n\n. The continuum is assumed to be unpolarized. Therefore, the continuum source vector is given by \n\n\n\n\n\n. The frequency-averaged PRD mean intensity vector is given by\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the 2 × 2 nonmagnetic angle-averaged PRD matrix (Domke & Hubeny 1988; Bommier 1997), and\n7\n\n\n\n\n\nThe Rayleigh phase matrix \n\n\n\n\n\n in the irreducible basis is given in Appendix A of Frisch (2007). It is useful to rewrite Equation (7) as\n8\n\n\n\n\n\nwhere\n9\n\n\n\n\n\n\n","Citation Text":["Megha et al. 2019"],"Citation Start End":[[801,818]]} {"Identifier":"2020ApJ...903....6M__Megha_et_al._2019_Instance_2","Paragraph":"In this paper, we consider resonance scattering on a two-level atom with an infinitely sharp and unpolarized lower level. As for the frequency redistribution, we consider both CRD and angle-averaged PRD. In an unmagnetized one-dimensional spherically symmetric atmosphere, the polarized radiation field is axially symmetric and is described by \n\n\n\n\n\n. We also take into account the effects of radial velocity fields. We solve the concerned transfer equation in the CMF and in the nonrelativistic regime of velocity fields. To efficiently handle the sphericity effects, we solve the spherical transfer equation in the (p, z) coordinate system (Hummer & Rybicki 1971), which is also called the tangent-ray method. Here z is the distance along the tangent rays and p is impact parameter (see Figure 1 in Megha et al. 2019). Following Frisch (2007), we express the Stokes vector components in terms of their irreducible components. From here on we present all the basic equations in the irreducible basis (see Sampoorna & Trujillo Bueno 2010 for details). The CMF polarized PRD transfer equation for a spherically symmetric medium in (p, z) representation under the nonrelativistic limit is given by (see also Equation (17) of Megha et al. 2019)\n1\n\n\n\n\n\nwhere x denotes the nondimensional frequency and \n\n\n\n\n\n denotes the irreducible Stokes vector with “+” and “−” referring to the outgoing and incoming rays, respectively. The radial optical depth is defined as dτr = −χl(r)dr, where r is the radial distance and χl(r) is the line averaged absorption coefficient. In the CMF the monochromatic optical depth along the tangent ray is given by dτ = [φ(x) + βc]dτr\/μ, where φ(x) is the line absorption profile function and βc = χc(r)\/χl(r) with χc(r) denoting the continuum absorption coefficient. The direction cosine of the tangent ray about the radius vector of the intercepting radial shell is given by \n\n\n\n\n\n. In Equation (1), \n\n\n\n\n\n denotes the CMF term, which has the form\n2\n\n\n\n\n\nwhere χ(r, x) = χl(r)φ(x) + χc(r), and\n3\n\n\n\n\n\nThe symbol V denotes the ratio of radial (vr) to the thermal (\n\n\n\n\n\n) velocities. In Equation (1), \n\n\n\n\n\n represents the irreducible CMF total source vector and is given by\n4\n\n\n\n\n\nwhere the line source vector is of the form\n5\n\n\n\n\n\nHere ϵ gives the probability of destruction of photons by inelastic collisions, Bν0 is the Planck function at the line center frequency ν0, and \n\n\n\n\n\n. The continuum is assumed to be unpolarized. Therefore, the continuum source vector is given by \n\n\n\n\n\n. The frequency-averaged PRD mean intensity vector is given by\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the 2 × 2 nonmagnetic angle-averaged PRD matrix (Domke & Hubeny 1988; Bommier 1997), and\n7\n\n\n\n\n\nThe Rayleigh phase matrix \n\n\n\n\n\n in the irreducible basis is given in Appendix A of Frisch (2007). It is useful to rewrite Equation (7) as\n8\n\n\n\n\n\nwhere\n9\n\n\n\n\n\n\n","Citation Text":["Megha et al. 2019"],"Citation Start End":[[1223,1240]]} {"Identifier":"2022MNRAS.512.4893Z__Simpson_et_al._2019_Instance_1","Paragraph":"The number density of SMGs in either BOSS1244 or BOSS1542 is significantly higher than that of the blank fields. It is reasonable to attribute the excess of SMGs to the overdensity at z = 2.24. This has been successfully verified with H α emitters (Shi et al. 2021; Zheng et al. 2021). We link the excess of SMGs in our two MAMMOTH fields to the presence of 850 $\\rm{\\mu m}$-detected SMG overdensity at z = 2.24. There are 43 (54) SMGs detected over an effective area of 264 arcmin2 in the deep 850 $\\rm{\\mu m}$ map of BOSS1244 (BOSS1542). Considering the redshift distribution, we calculate the fraction of SMGs located in 2.2 z 2.3 to be 5.7 per cent comparing to the whole redshift range in the AS2UDS survey (Dudzevičiūtė et al. 2020), which has a survey area of ∼1 deg2 and make the cosmic variance negligible (Simpson et al. 2019). Then we obtain that the volume density of SMGs in this redshift slice is 2.6 × 10−5 cMpc−3 at S850 ≥ 4.0 mJy in the blank fields. If we simply assume the two overdensities span a narrow redshift range (δz 0.042 given by the band width of H2S(1) filter), the volume of the redshift slice of z = 2.246 ± 0.021 over 264 arcmin2 corresponds to a co-moving box of 54.3 × 665.6 (=36142) h−3 cMpc3. If the excess of SMGs (i.e. (1.8–1)\/1.8 × 54 for BOSS1542) are associated with the z = 2.24 overdensities, we obtain that SMGs in the two overdensities may reach a volume density of ∼(40–70) × 10−5 cMpc−3, 15–30 times that of the blank fields. After enlarging the redshift slice of the two protoclusters to that of blank field (δz = 0.1), we still obtain the volume density of SMG to be 6–11 times that of the blank fields. The overdensity factor of SMGs, although with large uncertainties, is even higher than that of H α emission-line galaxies (HAEs) in these two protoclusters (Shi et al. 2021), indicating that there are more extreme starbursts with enhanced star formation in respect to normal SFGs (i.e. HAEs) in the two z = 2.24 protoclusters.","Citation Text":["Simpson et al. 2019"],"Citation Start End":[[818,837]]} {"Identifier":"2016MNRAS.456.4506E__Zeeuw_1985_Instance_1","Paragraph":"It is straightforward to generalize the proof to the instance of axisymmetric stellar systems with second velocity moments aligned in spheroidal coordinates (λ, μ, ϕ). This coordinate system has been introduced in equation (13) and is described in detail in, for example, Morse & Feshbach (1953) or Binney & Tremaine (2008). Here, we will show that if the second velocity moment ellipsoid is everywhere aligned in spheroidal coordinates (〈vλvϕ〉 = 〈vλvμ〉 = 〈vμvϕ〉 = 0), then the gravitational potential has Stäckel or separable form. Again, we construct the even part of the DF. Introducing canonical coordinates, the DF has the form ${F_{\\rm e}}(p_\\lambda ^2, p_\\mu ^2, p_\\phi ^2, \\lambda ,\\mu ,\\phi )$. The Hamiltonian is\n\n(44)\n\n\\begin{equation}\nH = {1\\over 2} \\Bigl ( {p_\\lambda ^2\\over P^2} + {p_\\mu ^2 \\over Q^2} + {p_\\phi ^2 \\over R^2} \\Bigr ) - \\psi (\\lambda ,\\mu ,\\phi ),\n\\end{equation}\n\nwhere the scale factors are P, Q and R are\n\n(45)\n\n\\begin{eqnarray}\nP^2 &=& {\\lambda -\\mu \\over 4(\\lambda + a)(\\lambda +b)},\\qquad Q^2 = {\\mu -\\lambda \\over 4(\\mu + a)(\\mu +b)},\\nonumber \\\\\nR^2 &=& {(\\lambda +a)(\\mu +a)\\over a-b},\n\\end{eqnarray}\n\nand a and b are constants (see for example the tables of Lynden-Bell 1962 or equation (6) of Evans & Lynden-Bell 1989 or Section 2 of de Zeeuw 1985). This implies that the DF can be re-written as ${F_{\\rm e}}(H, p_\\mu ^2, p_\\phi ^2, \\lambda ,\\mu ,\\phi ).$ Just as before, requiring the Poisson bracket {H, Fe} to vanish implies that ∂Fe\/∂λ also vanishes and so Fe is independent of λ. This leaves us with the condition\n\n(46)\n\n\\begin{equation}\nA {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} p_\\mu } - {\\mathrm{\\partial} \\psi \\over \\mathrm{\\partial} \\phi } {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} p_\\phi } = {p_\\mu \\over Q^2} {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} \\mu } + {p_\\phi \\over R^2} {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} \\phi }\n\\end{equation}\n\nwith\n\n(47)\n\n\\begin{eqnarray}\n&&{A ={1\\over \\lambda -\\mu }}\\nonumber\\\\\n&&{\\left[ {p_\\mu ^2\\over 2} {\\mathrm{\\partial} \\over \\mathrm{\\partial} \\mu }\\left( {\\lambda -\\mu \\over Q^2} \\right) \\!+\\! {p_\\phi ^2\\over 2} {\\mathrm{\\partial} \\over \\mathrm{\\partial} \\mu } \\left( {\\lambda \\!-\\!\\mu \\over R^2} \\right) - {\\mathrm{\\partial} \\over \\mathrm{\\partial} \\mu }\\left( (\\lambda -\\mu ) \\psi \\right) +H\\right].}\\nonumber\\\\\n\\end{eqnarray}\n\nAgain, the equation must hold on transforming pμ → −pμ, so that in the general case (i.e. ignoring degenerate cases like isotropy), we must have\n\n(48)\n\n\\begin{equation}\nA {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} p_\\mu } = {p_\\mu \\over Q^2} {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} \\mu }, \\qquad \\qquad {\\mathrm{\\partial} \\psi \\over \\mathrm{\\partial} \\phi } {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} p_\\phi }= {p_\\phi \\over R^2} {\\mathrm{\\partial} {F_{\\rm e}}\\over \\mathrm{\\partial} \\phi }.\n\\end{equation}\n\nMultiplying the first equation by λ − μ, differentiating with respect to λ at constant H and then using the definitions of the scale factors gives us the simple result\n\n(49)\n\n\\begin{equation}\n{\\mathrm{\\partial} ^2 \\over \\mathrm{\\partial} \\lambda \\mathrm{\\partial} \\mu } \\left( (\\lambda -\\mu )\\psi \\right) =0.\n\\end{equation}\n\nIntegrating up, this gives us\n\n(50)\n\n\\begin{equation}\n\\psi = {A(\\lambda ,\\phi ) - B (\\mu ,\\phi ) \\over \\lambda - \\mu },\n\\end{equation}\n\nwhere A(λ, ϕ) and B(μ, ϕ) are arbitrary.","Citation Text":["de Zeeuw 1985"],"Citation Start End":[[1291,1304]]} {"Identifier":"2019ApJ...880...53N__Bogdanov_et_al._2008_Instance_1","Paragraph":"In an attempt to perform a more robust analysis, potentially obtain stronger constraints on the MSP population, and break some parameter degeneracies, we consider a parameterized pulsar spin-down luminosity function \n\n\n\n\n\n (Johnston & Verbunt 1996). We will use this to balance the required X-ray energetics by assuming that \n\n\n\n\n\n and \n\n\n\n\n\n. This implies \n\n\n\n\n\n, with \n\n\n\n\n\n a normalization constant. Johnston & Verbunt (1996) inferred a typical GC value of γL ∼ 0.5, while Heinke et al. (2006) found γL ∼ 0.4–0.7 for Terzan 5, depending on the energy band. By defining \n\n\n\n\n\n, one can next recover the following quantities:\n25\n\n\n\n\n\n\n\n26\n\n\n\n\n\n\n\n27\n\n\n\n\n\n\n\n28\n\n\n\n\n\n\n\n29\n\n\n\n\n\nWe want to solve for four quantities: \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n (or, equivalently, \n\n\n\n\n\n), and γL; once these are fixed, we can infer the MSP population properties through the above equations. We note, however, that we are using this luminosity function to fit X-ray luminosities, which are integral quantities. We therefore expect to find degenerate solutions, as different combinations might yield the same integral luminosities. Thus, we need four constraints or measurements. We can use the same three constraints as before. Crucially, one needs to specify a fourth parameter ηX to convert from spin-down luminosities to X-ray luminosities. By fixing ηX, we implicitly fix the product \n\n\n\n\n\n. As a first attempt, let us assume ηX = 0.05% (e.g., for \n\n\n\n\n\n and \n\n\n\n\n\n erg s−1 to make the calculation consistent with the previous estimate). It is difficult to obtain the actual value for \n\n\n\n\n\n, given the effect of the GC cluster potential on the \n\n\n\n\n\n of each MSP (e.g., Bogdanov et al. 2008). If we could, this would further constrain the system via Equation (28). Heinke et al. (2006) noted that while they did not detect an X-ray MSP explicitly, one X-ray source could plausibly be an MSP based on the proximity to a radio MSP position; they also noted that more identifications of X-ray MSPs could be made as radio positions become available. We thus have additional constraints \n\n\n\n\n\n and \n\n\n\n\n\n (which may be used as checks on the consistency of the solutions we obtain). We do obtain a nonunique solution for each fixed value of ηX. However, ηX is not known, and the parameters that satisfy the other three constraints are quite degenerate, as expected. Table 2 indicates a number of parameter combinations that satisfy the observational constraints.25\n\n25\nA preliminary Markov chain Monte Carlo investigation (Foreman-Mackey et al. 2013) confirmed the degenerate nature of the free parameters (some are correlated), as well as their being quite unconstrained (reflected by asymmetrical and flat probability distributions, as well as elongated confidence contours). Best-fit values furthermore depend on the choice of priors\/parameter bounds. The median values are, however, similar to those in Table 2.\n It is clear that a different choice of ηX will favor a different solution that will imply a different value of \n\n\n\n\n\n (which also depends on the average moment of inertia \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n). For example, a higher value of ηX will yield a lower value of \n\n\n\n\n\n or \n\n\n\n\n\n for a given value of \n\n\n\n\n\n and keeping other parameters fixed. If we require \n\n\n\n\n\n to be the same as assumed in the model used to predict the pulsed emission, this may lead to unrealistic values for γL for a given ηX. Relaxing this requirement (which may easily be done, given other parameter uncertainties) implies more suitable values for the other parameters. It is therefore clear that the system of equations is very coupled and the parameters are degenerate, given the lack of suitable constraints. One may think to constrain the solution space by requiring \n\n\n\n\n\n, the latter being the estimated total number of visible MSPs in Terzan 5 as inferred from the Fermi-measured GeV energy flux (Abdo et al. 2010). However, this estimate is quite uncertain and does not contain uncertainties in distance (the square of which determines the γ-ray luminosity Lγ) and conversion efficiency of \n\n\n\n\n\n to Lγ, so this does not seem to be a strong constraint. Likewise, we chose \n\n\n\n\n\n when fitting the CR component, but this value is also subject to other model assumptions, such as MSP geometry and gap width. Finally, it seems that the last few entries in Table 2 might be the more plausible combinations in view of the independent constraints on γL ∼ 0.4–0.7 and \n\n\n\n\n\n (i.e., probably relatively small numbers of visible X-ray pulsars) gleaned from the analysis of Heinke et al. (2006). Thus, the uncertainty in several parameters, particularly ηX, as well as parameter degeneracies preclude us from making definite statements about the MSP population properties. Yet we see that there are several plausible solutions that characterize and constrain the MSP population's energetics, implying that the scenario of MSPs being responsible for the broadband SED may be justified and thus plausible.","Citation Text":["Bogdanov et al. 2008"],"Citation Start End":[[1649,1669]]} {"Identifier":"2017ApJ...837...97L__Jauzac_et_al._2015_Instance_1","Paragraph":"The newly discovered arcs and new spectroscopic redshifts have been incorporated into updated HFF+ versions of the Abell 2744 and MACSJ0416.1-2403 lensing models (Table 5); many of these have \n\n\n\n\n\n (see Figure 8 for a comparison of the arc redshift distributions adopted by the pre-HFF and new HFF+ lensing models; Cypriano et al. 2004; Okabe & Umetsu 2008; Zitrin et al. 2009; 2013; Okabe et al. 2010a, 2010b; Merten et al. 2011; Christensen et al. 2012; Mann & Ebeling 2012; Jauzac et al. 2014; Lam et al. 2014; Richard et al. 2014; Balestra et al. 2015; Diego et al. 2015; Grillo et al. 2015; Jauzac et al. 2015; Rodney et al. 2015; Wang et al. 2015; Kawamata et al. 2016). The incorporation of these new multiple image systems often results in a reduction in the statistical uncertainty in the galaxy magnifications for a given model. All of the public HFF lensing models provide a range of possible realizations from which the statistical uncertainty of a given model set may be calculated (typically 100 but no fewer than 30). We plot the cumulative distribution of the galaxy magnification uncertainties σ(model)\/\n\n\n\n\n\n, for the galaxies and photometric redshifts provided by the ASTRODEEP catalogs (Merlin et al. 2016; Castellano et al. 2016a) for Abell 2744 (Figure 9) and MACSJ0416.1-2403 (Figure 10). Generally, the statistical uncertainties are reduced for the models computed with the new HFF data sets, with more dramatic reductions for the methods that rely strongly upon the strong-lensing constraints. The parametric methods (CATS, Sharon, Zitrin, GLAFIC) report median statistical magnification errors of 0.2%–5%, while the non-parametric methods (Bradac Williams, Diego) report median statistical magnification errors of 2%–11% for the post-HFF calculations (green curves), versus 2%–22% and 2%–17% respectively for pre-HFF models (blue curves). (We note that the statistical errors for the MACSJ0416.1-2403 Bradac post-HFF models (Hoag et al. 2016) included additional uncertainties due to the photometric redshift uncertainties of the multiple images. These were not included in the pre-HFF Bradac model, and thus may explain why the post-HFF statistical errors are larger for this model.)","Citation Text":["Jauzac et al. 2015"],"Citation Start End":[[597,615]]} {"Identifier":"2015MNRAS.446..330W__Sanders_&_McGaugh_2002_Instance_1","Paragraph":"In SID\/Milgromian dynamics there appears an interesting effect that leads to an observable prediction which does not exist in the Newtonian plus DM model. It is relevant for a satellite object falling within the gravitational field of a host such that the host field does not vary significantly across the satellite. This external gravitational field effectively truncates the isothermal PDMH, as deduced by an observer who interprets the observations within Newtonian dynamics. The Milgromian dynamics\/MOND equation for a spherical, axisymmetric or cylindrical system embedded in an external field is (Milgrom 1983a; Sanders & McGaugh 2002)\n\n(24)\n\n\\begin{equation}\n{\\boldsymbol g}_{{\\rm N,i}}+{\\boldsymbol g}_{{\\rm N,e}}=\\mu (| ({\\boldsymbol g}_{\\rm i} + {\\boldsymbol g}_{\\rm e})|\/a_0) ({\\boldsymbol g}_{\\rm i}+{\\boldsymbol g}_{\\rm e}),\n\\end{equation}\n\nwhere ${\\boldsymbol g}_{{\\rm N,i}}$ is the Newtonian acceleration from the baryonic matter of the internal system, ${\\boldsymbol g}_{{\\rm N,e}}$ is the Newtonian acceleration from the baryonic matter of the external gravitational source generating the background uniform field and ${\\boldsymbol g}_{\\rm i}$ and ${\\boldsymbol g}_{\\rm e}$ are the internal and external gravitational accelerations. For an external field dominated system, $g_{\\rm e}=|{\\boldsymbol g}_{\\rm e}| \\gg g_{\\rm i}=|{\\boldsymbol g}_{\\rm i}|$, equation (24) is expanded around ge to lowest order as\n\n(25)\n\n\\begin{eqnarray}\ng_{{\\rm N,e}}&=&\\mu (|{\\boldsymbol g}_{\\rm e}|\/a_0) {\\boldsymbol g}_{\\rm e},\\nonumber \\\\\ng_{{\\rm N,i}}&=&\\mu (|{\\boldsymbol g}_{\\rm e}|\/a_0) {\\boldsymbol g}_{\\rm i},\n\\end{eqnarray}\n\nwith a dilation factor of $\\Delta _1=(1+{\\rm d}\\ln \\mu \/{\\rm d} \\ln x)_{x=g_{\\rm e}\/a_0}$. Δ1 approaches 1 in the Newtonian limit and approaches 2 in the deep-MOND limit. The value of Δ1 also depends on the direction relative to the external field (for more details see Milgrom 1983a; Bekenstein & Milgrom 1984; Zhao & Tian 2006). μ(x) = x in the low-acceleration regime where SID is valid (i.e. in deep-MOND limit).6","Citation Text":["Sanders & McGaugh 2002"],"Citation Start End":[[618,640]]} {"Identifier":"2017MNRAS.470.3206C__Lithwick_2013_Instance_1","Paragraph":"Our motivation for this work is manifold. First, we have incorporated the gas-accretion models of Papaloizou Nelson (2005) into the combined N-body and protoplanetary disc evolution code presented in Coleman Nelson (2014, 2016a), in order to increase the realism of the planetary system formation simulations that can be computed with this numerical tool. The purpose of this paper is to provide a simplified examination of gas accretion on to isolated, non-interacting planetary cores at a variety of orbital locations using the evolving disc models from Coleman Nelson (2016a), as a precursor to presenting simulations that consider the contemporaneous accretion of solids and gas on to protoplanets under the influence of migration within the evolving disc models. A second motivation is to examine how accreting planets with different initial core masses at different locations in the disc evolve within disc lifetimes. Observations indicate the presence of exoplanets (super-Earths, Neptunes and Jupiters) that are likely to be gas bearing with a broad range of orbital radii, covering the interval 0.04au ap 100au (e.g. Marois etal. 2008; Borucki etal. 2011). Analysis of the occurrence rates as a function of planet radius in the Kepler data suggests that planets with radii in the range 0.85 Rp 4R are present around 50percent of Sun-like stars (e.g. Fressin etal. 2013), which is consonant with the results from earlier radial velocity surveys that focused on low-mass planets (Mayor etal. 2011). Transit timing variations (Wu Lithwick 2013; Hadden Lithwick 2016) and radial velocity measurements (Marcy etal. 2014; Weiss etal. 2016) indicate that the super-Earths and Neptunes in the Kepler data with radii Rp4R have masses in the range 2 Mp 15M, and show a tendency for the bulk density to increase for Rp1.5R and decrease for 1.5Rp4R, indicating that the smaller planets are composed almost entirely of solids, whereas the larger planets have larger radii due to the presence of significant gaseous envelopes that have been accreted during formation. Comparing theoretical models with the data suggests that the gaseous envelopes contribute little to the total masses of the super-Earths and Neptunes (Lopez Fortney 2014), with recent estimates indicating that planets with Rp 1.2R contain 1percent gas by mass, rising to 5percent for planets with Rp3R (Wolfgang Lopez 2015). Considering the gas giant exoplanets, numerous attempts have been made to constrain the core masses and total heavy element abundances of those transiting planets that have mass estimates from radial velocity measurements using evolutionary models of the internal structure (Guillot etal. 2006; Burrows etal. 2007; Miller Fortney 2011; Thorngren etal. 2016). These studies provide a strong indication that the majority of gas giant exoplanets are substantially enriched with heavy elements relative to their host stars, with heavy element masses typically being 20M or larger. These results are consistent with the idea that giant planets form when a sufficiently massive (i.e. in the range 1015M) core forms that is able to accrete gas and undergo runaway gas accretion sufficiently early in the disc lifetime, in basic agreement with the theoretical core accretion models. In the absence of a sufficiently massive core that forms early enough, a more common outcome is the formation of super-Earths or Neptunes that fail to become gas giants because of the relatively slow rate of gas accretion until the envelope mass becomes comparable to the core mass. It is clearly of interest to address the above observational results through theoretical modelling of in situ planet formation, and to compare the outcomes of our calculations with recent work that has considered gas accretion on to planets with short (Lee, Chiang Ormel 2014; Batygin, Bodenheimer Laughlin 2016) and long orbital periods (Piso Youdin 2014; Piso, Youdin Murray-Clay 2015). Our third motivation is to consider the longer term cooling and contraction of the gaseous envelopes for those planets that remain in a state of quasi-static equilibrium throughout the period of gas accretion when the disc is present. Since the observations are typically relevant to exoplanets that have existed around their stars for Gyrs, they will have evolved for time periods of this duration after the epoch of formation. This is the first time that our models have been used to examine this longer term evolution, and our approach is similar to that used in recent population synthesis studies (see the recent review by Mordasini etal. 2015).","Citation Text":["Wu Lithwick 2013"],"Citation Start End":[[1540,1557]]} {"Identifier":"2016ApJ...819...66D__Kirsanova_et_al._2008_Instance_1","Paragraph":"The extended star-forming region S235 is known to be a part of the giant molecular cloud G174+2.5 in the Perseus Spiral Arm (e.g., Heyer et al. 1996) and contains two known sites: the S235 complex and the S235AB region (see Figure 1 in Dewangan & Anandarao 2011 and also Figure 1 in Kirsanova et al. 2014). The present work is focused on the S235 complex and does not include the S235AB region. Different values of the distance (1.36, 1.59, 1.8, 2.1, and 2.5 kpc) to the extended star-forming region S235 have been reported in the literature (e.g., Georgelin et al. 1973; Israel & Felli 1978; Evans & Blair 1981; Brand & Blitz 1993; Burns et al. 2015; Foster & Brunt 2015). In the present work, we have chosen a distance of 1.8 kpc following Evans & Blair (1981), which is an intermediate value of the published distance range. The H ii region associated with the S235 complex is predominantly ionized by a single massive star, BD+35o1201, of O9.5V type (Georgelin et al. 1973). The S235 complex has been studied using multiple data sets spanning near-infrared (NIR) to radio wavelengths. The S235 complex is known as an active site of star formation, harboring young stellar clusters (e.g., Kirsanova et al. 2008; Camargo et al. 2011; Dewangan & Anandarao 2011; Chavarría et al. 2014) associated with known star-forming subregions, namely East 1, East 2, and the Central region (e.g., Kirsanova et al. 2008). In our previous work on the S235 complex using Spitzer-IRAC data (Dewangan & Anandarao 2011, hereafter Paper I) we detected several young stellar objects (YSOs) including a high mass protostellar object (HMPO) candidate as well as signatures of outflow activities. Using 13CO (1−0) line data, Kirsanova et al. (2008) found three molecular gas components (i.e., −18 km s−1\n\n\n\n\n\n km s−1 (red), −21 km s−1 \n\n\n\n\n\n km s−1 (central), and −25 km s−1 \n\n\n\n\n\n km s−1 (blue)) in the direction of the S235 complex. However, the complex is well traced in mainly two molecular gas components (central and blue). More recently, Kirsanova et al. (2014) derived physical parameters of dense gas (i.e., gas density and temperature) in subregions of the complex using ammonia (NH3) line observations. However, the properties of dense gas have not been explored with respect to the ionizing star location. Previous studies indicated that the S235 H ii region is interacting with its surrounding molecular cloud and the S235 complex has been cited as a possible site of triggered star formation (Kirsanova et al. 2008, 2014; Camargo et al. 2011).","Citation Text":["Kirsanova et al. 2008"],"Citation Start End":[[1192,1213]]} {"Identifier":"2016ApJ...819...66D__Kirsanova_et_al._2008_Instance_2","Paragraph":"The extended star-forming region S235 is known to be a part of the giant molecular cloud G174+2.5 in the Perseus Spiral Arm (e.g., Heyer et al. 1996) and contains two known sites: the S235 complex and the S235AB region (see Figure 1 in Dewangan & Anandarao 2011 and also Figure 1 in Kirsanova et al. 2014). The present work is focused on the S235 complex and does not include the S235AB region. Different values of the distance (1.36, 1.59, 1.8, 2.1, and 2.5 kpc) to the extended star-forming region S235 have been reported in the literature (e.g., Georgelin et al. 1973; Israel & Felli 1978; Evans & Blair 1981; Brand & Blitz 1993; Burns et al. 2015; Foster & Brunt 2015). In the present work, we have chosen a distance of 1.8 kpc following Evans & Blair (1981), which is an intermediate value of the published distance range. The H ii region associated with the S235 complex is predominantly ionized by a single massive star, BD+35o1201, of O9.5V type (Georgelin et al. 1973). The S235 complex has been studied using multiple data sets spanning near-infrared (NIR) to radio wavelengths. The S235 complex is known as an active site of star formation, harboring young stellar clusters (e.g., Kirsanova et al. 2008; Camargo et al. 2011; Dewangan & Anandarao 2011; Chavarría et al. 2014) associated with known star-forming subregions, namely East 1, East 2, and the Central region (e.g., Kirsanova et al. 2008). In our previous work on the S235 complex using Spitzer-IRAC data (Dewangan & Anandarao 2011, hereafter Paper I) we detected several young stellar objects (YSOs) including a high mass protostellar object (HMPO) candidate as well as signatures of outflow activities. Using 13CO (1−0) line data, Kirsanova et al. (2008) found three molecular gas components (i.e., −18 km s−1\n\n\n\n\n\n km s−1 (red), −21 km s−1 \n\n\n\n\n\n km s−1 (central), and −25 km s−1 \n\n\n\n\n\n km s−1 (blue)) in the direction of the S235 complex. However, the complex is well traced in mainly two molecular gas components (central and blue). More recently, Kirsanova et al. (2014) derived physical parameters of dense gas (i.e., gas density and temperature) in subregions of the complex using ammonia (NH3) line observations. However, the properties of dense gas have not been explored with respect to the ionizing star location. Previous studies indicated that the S235 H ii region is interacting with its surrounding molecular cloud and the S235 complex has been cited as a possible site of triggered star formation (Kirsanova et al. 2008, 2014; Camargo et al. 2011).","Citation Text":["Kirsanova et al. 2008"],"Citation Start End":[[1386,1407]]} {"Identifier":"2016ApJ...819...66D__Kirsanova_et_al._2008_Instance_3","Paragraph":"The extended star-forming region S235 is known to be a part of the giant molecular cloud G174+2.5 in the Perseus Spiral Arm (e.g., Heyer et al. 1996) and contains two known sites: the S235 complex and the S235AB region (see Figure 1 in Dewangan & Anandarao 2011 and also Figure 1 in Kirsanova et al. 2014). The present work is focused on the S235 complex and does not include the S235AB region. Different values of the distance (1.36, 1.59, 1.8, 2.1, and 2.5 kpc) to the extended star-forming region S235 have been reported in the literature (e.g., Georgelin et al. 1973; Israel & Felli 1978; Evans & Blair 1981; Brand & Blitz 1993; Burns et al. 2015; Foster & Brunt 2015). In the present work, we have chosen a distance of 1.8 kpc following Evans & Blair (1981), which is an intermediate value of the published distance range. The H ii region associated with the S235 complex is predominantly ionized by a single massive star, BD+35o1201, of O9.5V type (Georgelin et al. 1973). The S235 complex has been studied using multiple data sets spanning near-infrared (NIR) to radio wavelengths. The S235 complex is known as an active site of star formation, harboring young stellar clusters (e.g., Kirsanova et al. 2008; Camargo et al. 2011; Dewangan & Anandarao 2011; Chavarría et al. 2014) associated with known star-forming subregions, namely East 1, East 2, and the Central region (e.g., Kirsanova et al. 2008). In our previous work on the S235 complex using Spitzer-IRAC data (Dewangan & Anandarao 2011, hereafter Paper I) we detected several young stellar objects (YSOs) including a high mass protostellar object (HMPO) candidate as well as signatures of outflow activities. Using 13CO (1−0) line data, Kirsanova et al. (2008) found three molecular gas components (i.e., −18 km s−1\n\n\n\n\n\n km s−1 (red), −21 km s−1 \n\n\n\n\n\n km s−1 (central), and −25 km s−1 \n\n\n\n\n\n km s−1 (blue)) in the direction of the S235 complex. However, the complex is well traced in mainly two molecular gas components (central and blue). More recently, Kirsanova et al. (2014) derived physical parameters of dense gas (i.e., gas density and temperature) in subregions of the complex using ammonia (NH3) line observations. However, the properties of dense gas have not been explored with respect to the ionizing star location. Previous studies indicated that the S235 H ii region is interacting with its surrounding molecular cloud and the S235 complex has been cited as a possible site of triggered star formation (Kirsanova et al. 2008, 2014; Camargo et al. 2011).","Citation Text":["Kirsanova et al. (2008)"],"Citation Start End":[[1703,1726]]} {"Identifier":"2016ApJ...819...66D__Kirsanova_et_al._2008_Instance_4","Paragraph":"The extended star-forming region S235 is known to be a part of the giant molecular cloud G174+2.5 in the Perseus Spiral Arm (e.g., Heyer et al. 1996) and contains two known sites: the S235 complex and the S235AB region (see Figure 1 in Dewangan & Anandarao 2011 and also Figure 1 in Kirsanova et al. 2014). The present work is focused on the S235 complex and does not include the S235AB region. Different values of the distance (1.36, 1.59, 1.8, 2.1, and 2.5 kpc) to the extended star-forming region S235 have been reported in the literature (e.g., Georgelin et al. 1973; Israel & Felli 1978; Evans & Blair 1981; Brand & Blitz 1993; Burns et al. 2015; Foster & Brunt 2015). In the present work, we have chosen a distance of 1.8 kpc following Evans & Blair (1981), which is an intermediate value of the published distance range. The H ii region associated with the S235 complex is predominantly ionized by a single massive star, BD+35o1201, of O9.5V type (Georgelin et al. 1973). The S235 complex has been studied using multiple data sets spanning near-infrared (NIR) to radio wavelengths. The S235 complex is known as an active site of star formation, harboring young stellar clusters (e.g., Kirsanova et al. 2008; Camargo et al. 2011; Dewangan & Anandarao 2011; Chavarría et al. 2014) associated with known star-forming subregions, namely East 1, East 2, and the Central region (e.g., Kirsanova et al. 2008). In our previous work on the S235 complex using Spitzer-IRAC data (Dewangan & Anandarao 2011, hereafter Paper I) we detected several young stellar objects (YSOs) including a high mass protostellar object (HMPO) candidate as well as signatures of outflow activities. Using 13CO (1−0) line data, Kirsanova et al. (2008) found three molecular gas components (i.e., −18 km s−1\n\n\n\n\n\n km s−1 (red), −21 km s−1 \n\n\n\n\n\n km s−1 (central), and −25 km s−1 \n\n\n\n\n\n km s−1 (blue)) in the direction of the S235 complex. However, the complex is well traced in mainly two molecular gas components (central and blue). More recently, Kirsanova et al. (2014) derived physical parameters of dense gas (i.e., gas density and temperature) in subregions of the complex using ammonia (NH3) line observations. However, the properties of dense gas have not been explored with respect to the ionizing star location. Previous studies indicated that the S235 H ii region is interacting with its surrounding molecular cloud and the S235 complex has been cited as a possible site of triggered star formation (Kirsanova et al. 2008, 2014; Camargo et al. 2011).","Citation Text":["Kirsanova et al. 2008"],"Citation Start End":[[2485,2506]]} {"Identifier":"2020ApJ...898...92C__Horn_et_al._2004_Instance_1","Paragraph":"The first interstellar discovery of MF took place in 1975 from the microwave emission spectrum of Sgr B2, which agrees with the rotational constants of the syn isomer (Curl 1959; Brown et al. 1975; Nummelin et al. 2000). Subsequently, it was detected in several other sources such as comet Hale–Bopp, and protostars and hot corinos (e.g., in Orion A and the protoplanetary nebula CRL 618) (Ellder et al. 1980; Ikeda et al. 2001; Cazaux et al. 2003; Bottinelli et al. 2004a, 2004b; Remijan et al. 2005, 2006; Remijan & Hollis 2006). Later, the less stable trans rotamer was detected in both the laboratory and the interstellar medium (ISM; Ruschin & Bauer 1980; Blom & Günthard 1981; Müller et al. 1983; Neill et al. 2011, 2012). The detailed mechanistic route for the interstellar synthesis of MF is a subject of considerable debate (Horn et al. 2004; Herbst 2005; Garrod & Herbst 2006; Snyder 2006; Bennett & Kaiser 2007; Occhiogrosso et al. 2011; Lawson et al. 2012). The initially assumed gas-phase model involving an ion–molecule reaction of protonated methanol (\n\n\n\n\n\n) with formaldehyde (H2CO) fails to reproduce the large MF column density, because this pathway demands a significant activation barrier (∼128 kJ mol−1) for one of the intermediate steps (Horn et al. 2004). Instead, gas-phase radiative association between the methyl cation (\n\n\n\n\n\n) and formic acid (HCOOH) seems energetically promising to produce H+MF and thereafter neutral MF via dissociative recombination with electrons:\n1\n\n\n\n\n\n\n\n2\n\n\n\n\n\nHowever, this reaction scheme fails to reproduce the huge MF concentration observed in hot cores (Horn et al. 2004). Alternative routes suggested more recently involve ion–molecule reactions with a low barrier or no barrier between protonated methanol and formic acid (acid-catalyzed Fischer esterification) or between protonated formic acid and methanol (\n\n\n\n\n\n transfer):\n3\n\n\n\n\n\n\n\n4\n\n\n\n\n\nfollowed by reaction (2) or exothermic proton transfer of \n\n\n\n\n\n (H+MF) to a base with a higher proton affinity than MF (Ehrenfreund & Charnley 2000; Neill et al. 2011, 2012).","Citation Text":["Horn et al. 2004"],"Citation Start End":[[834,850]]} {"Identifier":"2020ApJ...898...92C__Horn_et_al._2004_Instance_2","Paragraph":"The first interstellar discovery of MF took place in 1975 from the microwave emission spectrum of Sgr B2, which agrees with the rotational constants of the syn isomer (Curl 1959; Brown et al. 1975; Nummelin et al. 2000). Subsequently, it was detected in several other sources such as comet Hale–Bopp, and protostars and hot corinos (e.g., in Orion A and the protoplanetary nebula CRL 618) (Ellder et al. 1980; Ikeda et al. 2001; Cazaux et al. 2003; Bottinelli et al. 2004a, 2004b; Remijan et al. 2005, 2006; Remijan & Hollis 2006). Later, the less stable trans rotamer was detected in both the laboratory and the interstellar medium (ISM; Ruschin & Bauer 1980; Blom & Günthard 1981; Müller et al. 1983; Neill et al. 2011, 2012). The detailed mechanistic route for the interstellar synthesis of MF is a subject of considerable debate (Horn et al. 2004; Herbst 2005; Garrod & Herbst 2006; Snyder 2006; Bennett & Kaiser 2007; Occhiogrosso et al. 2011; Lawson et al. 2012). The initially assumed gas-phase model involving an ion–molecule reaction of protonated methanol (\n\n\n\n\n\n) with formaldehyde (H2CO) fails to reproduce the large MF column density, because this pathway demands a significant activation barrier (∼128 kJ mol−1) for one of the intermediate steps (Horn et al. 2004). Instead, gas-phase radiative association between the methyl cation (\n\n\n\n\n\n) and formic acid (HCOOH) seems energetically promising to produce H+MF and thereafter neutral MF via dissociative recombination with electrons:\n1\n\n\n\n\n\n\n\n2\n\n\n\n\n\nHowever, this reaction scheme fails to reproduce the huge MF concentration observed in hot cores (Horn et al. 2004). Alternative routes suggested more recently involve ion–molecule reactions with a low barrier or no barrier between protonated methanol and formic acid (acid-catalyzed Fischer esterification) or between protonated formic acid and methanol (\n\n\n\n\n\n transfer):\n3\n\n\n\n\n\n\n\n4\n\n\n\n\n\nfollowed by reaction (2) or exothermic proton transfer of \n\n\n\n\n\n (H+MF) to a base with a higher proton affinity than MF (Ehrenfreund & Charnley 2000; Neill et al. 2011, 2012).","Citation Text":["Horn et al. 2004"],"Citation Start End":[[1261,1277]]} {"Identifier":"2020ApJ...898...92C__Horn_et_al._2004_Instance_3","Paragraph":"The first interstellar discovery of MF took place in 1975 from the microwave emission spectrum of Sgr B2, which agrees with the rotational constants of the syn isomer (Curl 1959; Brown et al. 1975; Nummelin et al. 2000). Subsequently, it was detected in several other sources such as comet Hale–Bopp, and protostars and hot corinos (e.g., in Orion A and the protoplanetary nebula CRL 618) (Ellder et al. 1980; Ikeda et al. 2001; Cazaux et al. 2003; Bottinelli et al. 2004a, 2004b; Remijan et al. 2005, 2006; Remijan & Hollis 2006). Later, the less stable trans rotamer was detected in both the laboratory and the interstellar medium (ISM; Ruschin & Bauer 1980; Blom & Günthard 1981; Müller et al. 1983; Neill et al. 2011, 2012). The detailed mechanistic route for the interstellar synthesis of MF is a subject of considerable debate (Horn et al. 2004; Herbst 2005; Garrod & Herbst 2006; Snyder 2006; Bennett & Kaiser 2007; Occhiogrosso et al. 2011; Lawson et al. 2012). The initially assumed gas-phase model involving an ion–molecule reaction of protonated methanol (\n\n\n\n\n\n) with formaldehyde (H2CO) fails to reproduce the large MF column density, because this pathway demands a significant activation barrier (∼128 kJ mol−1) for one of the intermediate steps (Horn et al. 2004). Instead, gas-phase radiative association between the methyl cation (\n\n\n\n\n\n) and formic acid (HCOOH) seems energetically promising to produce H+MF and thereafter neutral MF via dissociative recombination with electrons:\n1\n\n\n\n\n\n\n\n2\n\n\n\n\n\nHowever, this reaction scheme fails to reproduce the huge MF concentration observed in hot cores (Horn et al. 2004). Alternative routes suggested more recently involve ion–molecule reactions with a low barrier or no barrier between protonated methanol and formic acid (acid-catalyzed Fischer esterification) or between protonated formic acid and methanol (\n\n\n\n\n\n transfer):\n3\n\n\n\n\n\n\n\n4\n\n\n\n\n\nfollowed by reaction (2) or exothermic proton transfer of \n\n\n\n\n\n (H+MF) to a base with a higher proton affinity than MF (Ehrenfreund & Charnley 2000; Neill et al. 2011, 2012).","Citation Text":["Horn et al. 2004"],"Citation Start End":[[1613,1629]]} {"Identifier":"2018ApJ...863..198P__Shapley_et_al._2003_Instance_1","Paragraph":"The third scenario to consider is emission from the quasar host galaxy. The approach of using the residual flux in DLA troughs to observe the Lyα emission associated with star formation in the host galaxies has been studied extensively (e.g., Kulkarni et al. 2006; Fynbo et al. 2010; Finley et al. 2013; Noterdaeme et al. 2014). Using the Kennicutt et al. (2008) calibration \n\n\n\n\n\n and assuming an intensity ratio of \n\n\n\n\n\n for the case B recombination, we estimate a star formation ratio of \n\n\n\n\n\n based on the luminosity of the residual Lyα emission. This is much higher than estimates of the SFR in quasar host galaxies (\n\n\n\n\n\n e.g., Ho 2005; Cai et al. 2014) and in the high-redshift Lyman break galaxies and Lyα emitters (\n\n\n\n\n\n e.g., Shapley et al. 2003; Erb et al. 2006; Gronwall et al. 2007). To further check whether the residual Lyα emission originated from the star formation, we compare the colors (the flux density ratios: FUV\/NUV and NUV\/Lyα) of the residues with those of the galaxies with active star formation. The comparison galaxies are selected from the starburst original 1999 data set (Leitherer et al. 1999). The spectral energy distributions (SEDs) with “Topic—stellar continua” and “Quantity—stellar emission only” (Figures 7–12 on the Starburst99 website http:\/\/www.stsci.edu\/science\/starburst99\/docs\/table-index.html) are used to compute the galaxy’s colors. The starlight models present in a homogeneous way for five metallicities between Z = 0.040 and 0.001 and three choices of the initial mass function. The age coverage is from 1 Myr to 1 Gyr, and both star formation laws (instantaneous and continuous) are contained. The SEDs placed at the quasar’s redshift are extracted from the flux densities at the effective wavelengths of the FUV\/NUV filters and 1215.6 Å. Figure 3(a) shows that SDSS J1259+6212 seriously deviates from the star-forming galaxy group. At wavelengths of a few hundred Angstroms, SDSS J1259+6212 has much bluer slopes than the bluest galaxy continuum. In Fathivavsari et al. (2018), strong and narrow Lyα emission is reported in 155 eclipsing damped Lyα systems, which is revealed with certainty as the narrow emission line from the host galaxy. However, the residual Lyα emission of SDSS J1259+6212 fills in the sub-DLA trough rather, forming a narrow peaked profile, and its luminosity is also higher than that from Fathivavsari et al., eclipsing the DLA sample. Thus, the host galaxy scenario is questionable.","Citation Text":["Shapley et al. 2003"],"Citation Start End":[[740,759]]} {"Identifier":"2017AandA...598A..66P__Chemin_et_al._(2015)_Instance_1","Paragraph":"In both models, as we will see, the thick disc scale length is about a factor of two shorter than that of the thin disc, in agreement with the results by Bovy et al. (2012a). The choice of presenting two mass models for the mass distribution of our Galaxy is mainly dictated by two reasons. First, the need to add a central bulge to the global gravitational potential to reproduce the rotation curve in the inner kpcs of the Milky Way strongly depends on the observational data with which one compares the theoretical curve: to reproduce the rise observed in the inner kpcs (see the observational data adopted by Caldwell & Ostriker 1981), Allen & Santillan (1991) introduced a central mass concentration, whose mass is about 15% of the disc mass. However, the central rise observed in the rotation of the molecular gas in the inner Galaxy (for more recent estimates see, for example, Sofue 2012) may be an effect of non circular motions generated by large scale asymmetries like the bar, as has been shown recently by Chemin et al. (2015). Moreover, this feature is not reported in all the observational studies (see, for example, Reid et al. 2014). Secondly, there is growing evidence that the mass of any classical bulge, if present in the Milky Way, must be small (Shen et al. 2010; Kunder et al. 2012, 2016; Di Matteo et al. 2014, 2015). For these reasons, we prefer to present a second model, our Model II, which does not include any spherical central component, and which is still compatible with the rotation curve of the Galaxy, as given by Reid et al. (2014). Because it has been widely used in the last decades, and due to the facility of its implementation, we explicitly aim at generating Galactic models similar to the Allen & Santillan (1991) model, so to make any implementation of these new models, and any comparison with Allen & Santillan (1991), straightforward. As for the model proposed by Allen & Santillan (1991), Models I and II are axisymmetric and time-independent, and do not include stellar asymmetries such as a bar or spiral arms. No truncation is assumed for the discs, while the halo is truncated at 100 kpc, in agreement with the choice of Allen & Santillan (1991). As we describe in the following section, the analytic forms for the discs, halo, and bulge potentials are the same as those adopted by Allen & Santillan (1991). To allow an easy comparison with the Allen & Santillan (1991) model, in the following we will make use of the same system of units adopted by these authors: the potential is given in units of 100 km2\/ s2, lengths are in kpc, masses in units of 2.32 × 107M⊙, time in units of 0.1 Gyr, velocities in units of 10 km s-1 and the vertical force in units of 10-9 cm s2. In these units, the gravitational constant G is equal to 1 and the mass volume density is in units of 2.32 × 107M⊙\/ kpc3. ","Citation Text":["Chemin et al. (2015)"],"Citation Start End":[[1020,1040]]} {"Identifier":"2022MNRAS.517.4637P__Seo_et_al._2010_Instance_1","Paragraph":"21 cm Intensity Mapping (IM) is a promising technique to map the cosmological large scale distribution of matter through the observation of 21 cm radio emission\/absorption of neutral hydrogen gas (H i), while not requiring the detection of individual sources (Bharadwaj, Nath & Sethi 2001; Battye, Davies & Weller 2004) and has been largely explored in the context of the search for the EoR (Epoch of Reionization) signal (Pritchard & Loeb 2008; Morales & Wyithe 2010). Subsequently, it was suggested that post-EoR 21 cm Intensity Mapping surveys could be used to constrain dark energy through the measurement of the Baryon Acoustic Oscillations (BAO) scale (Chang et al. 2008; Seo et al. 2010; Ansari et al. 2012) in the large scale structure (LSS) distribution, over a broad redshift range (z ≲ 6). Such surveys require instruments with large instantaneous bandwidth and field of view and several groups have built dense interferometric arrays to explore IM, such as CHIME (Bandura et al. 2014) or Tianlai (Chen 2012) in the last decade. Smaller instruments such as PAON4 (Ansari et al. 2020) and BMX (O’Connor et al. 2021) have also been built to explore specific technical aspects of these arrays, as well as transit mode operation and calibration. CHIME has proved to be a powerful fast radio burst and pulsar observation machine (The CHIME\/FRB Collaboration 2021) and has motivated the design and construction of larger, dish-based, dense interferometric arrays such as HIRAX (Newburgh et al. 2016) and CHORD (Vanderlinde et al. 2019). Non-interferometric surveys have also been considered, such as BINGO (Battye et al. 2016; Wuensche et al. 2022), FAST (Hu et al. 2020) or using the SKA precursor MeerKAT (Wang et al. 2021). Intensity Mapping is also being used to search for signals from the EoR and the cosmic dawn, at redshifts above z ≳ 10, by several large radio-interferometers, such as LOFAR (van Haarlem et al. 2013), MWA (Tingay et al. 2013), HERA (DeBoer et al. 2017), and LWA (Eastwood et al. 2018). It is also planned to be used with SKA-low (Mondal et al. 2020).","Citation Text":["Seo et al. 2010"],"Citation Start End":[[678,693]]} {"Identifier":"2022MNRAS.517.4637PBharadwaj,_Nath_&_Sethi_2001_Instance_1","Paragraph":"21 cm Intensity Mapping (IM) is a promising technique to map the cosmological large scale distribution of matter through the observation of 21 cm radio emission\/absorption of neutral hydrogen gas (H i), while not requiring the detection of individual sources (Bharadwaj, Nath & Sethi 2001; Battye, Davies & Weller 2004) and has been largely explored in the context of the search for the EoR (Epoch of Reionization) signal (Pritchard & Loeb 2008; Morales & Wyithe 2010). Subsequently, it was suggested that post-EoR 21 cm Intensity Mapping surveys could be used to constrain dark energy through the measurement of the Baryon Acoustic Oscillations (BAO) scale (Chang et al. 2008; Seo et al. 2010; Ansari et al. 2012) in the large scale structure (LSS) distribution, over a broad redshift range (z ≲ 6). Such surveys require instruments with large instantaneous bandwidth and field of view and several groups have built dense interferometric arrays to explore IM, such as CHIME (Bandura et al. 2014) or Tianlai (Chen 2012) in the last decade. Smaller instruments such as PAON4 (Ansari et al. 2020) and BMX (O’Connor et al. 2021) have also been built to explore specific technical aspects of these arrays, as well as transit mode operation and calibration. CHIME has proved to be a powerful fast radio burst and pulsar observation machine (The CHIME\/FRB Collaboration 2021) and has motivated the design and construction of larger, dish-based, dense interferometric arrays such as HIRAX (Newburgh et al. 2016) and CHORD (Vanderlinde et al. 2019). Non-interferometric surveys have also been considered, such as BINGO (Battye et al. 2016; Wuensche et al. 2022), FAST (Hu et al. 2020) or using the SKA precursor MeerKAT (Wang et al. 2021). Intensity Mapping is also being used to search for signals from the EoR and the cosmic dawn, at redshifts above z ≳ 10, by several large radio-interferometers, such as LOFAR (van Haarlem et al. 2013), MWA (Tingay et al. 2013), HERA (DeBoer et al. 2017), and LWA (Eastwood et al. 2018). It is also planned to be used with SKA-low (Mondal et al. 2020).","Citation Text":["Bharadwaj, Nath & Sethi 2001"],"Citation Start End":[[260,288]]} {"Identifier":"2022MNRAS.517.4637PBandura_et_al._2014_Instance_1","Paragraph":"21 cm Intensity Mapping (IM) is a promising technique to map the cosmological large scale distribution of matter through the observation of 21 cm radio emission\/absorption of neutral hydrogen gas (H i), while not requiring the detection of individual sources (Bharadwaj, Nath & Sethi 2001; Battye, Davies & Weller 2004) and has been largely explored in the context of the search for the EoR (Epoch of Reionization) signal (Pritchard & Loeb 2008; Morales & Wyithe 2010). Subsequently, it was suggested that post-EoR 21 cm Intensity Mapping surveys could be used to constrain dark energy through the measurement of the Baryon Acoustic Oscillations (BAO) scale (Chang et al. 2008; Seo et al. 2010; Ansari et al. 2012) in the large scale structure (LSS) distribution, over a broad redshift range (z ≲ 6). Such surveys require instruments with large instantaneous bandwidth and field of view and several groups have built dense interferometric arrays to explore IM, such as CHIME (Bandura et al. 2014) or Tianlai (Chen 2012) in the last decade. Smaller instruments such as PAON4 (Ansari et al. 2020) and BMX (O’Connor et al. 2021) have also been built to explore specific technical aspects of these arrays, as well as transit mode operation and calibration. CHIME has proved to be a powerful fast radio burst and pulsar observation machine (The CHIME\/FRB Collaboration 2021) and has motivated the design and construction of larger, dish-based, dense interferometric arrays such as HIRAX (Newburgh et al. 2016) and CHORD (Vanderlinde et al. 2019). Non-interferometric surveys have also been considered, such as BINGO (Battye et al. 2016; Wuensche et al. 2022), FAST (Hu et al. 2020) or using the SKA precursor MeerKAT (Wang et al. 2021). Intensity Mapping is also being used to search for signals from the EoR and the cosmic dawn, at redshifts above z ≳ 10, by several large radio-interferometers, such as LOFAR (van Haarlem et al. 2013), MWA (Tingay et al. 2013), HERA (DeBoer et al. 2017), and LWA (Eastwood et al. 2018). It is also planned to be used with SKA-low (Mondal et al. 2020).","Citation Text":["Bandura et al. 2014"],"Citation Start End":[[976,995]]} {"Identifier":"2022MNRAS.517.4637PO’Connor_et_al._2021_Instance_1","Paragraph":"21 cm Intensity Mapping (IM) is a promising technique to map the cosmological large scale distribution of matter through the observation of 21 cm radio emission\/absorption of neutral hydrogen gas (H i), while not requiring the detection of individual sources (Bharadwaj, Nath & Sethi 2001; Battye, Davies & Weller 2004) and has been largely explored in the context of the search for the EoR (Epoch of Reionization) signal (Pritchard & Loeb 2008; Morales & Wyithe 2010). Subsequently, it was suggested that post-EoR 21 cm Intensity Mapping surveys could be used to constrain dark energy through the measurement of the Baryon Acoustic Oscillations (BAO) scale (Chang et al. 2008; Seo et al. 2010; Ansari et al. 2012) in the large scale structure (LSS) distribution, over a broad redshift range (z ≲ 6). Such surveys require instruments with large instantaneous bandwidth and field of view and several groups have built dense interferometric arrays to explore IM, such as CHIME (Bandura et al. 2014) or Tianlai (Chen 2012) in the last decade. Smaller instruments such as PAON4 (Ansari et al. 2020) and BMX (O’Connor et al. 2021) have also been built to explore specific technical aspects of these arrays, as well as transit mode operation and calibration. CHIME has proved to be a powerful fast radio burst and pulsar observation machine (The CHIME\/FRB Collaboration 2021) and has motivated the design and construction of larger, dish-based, dense interferometric arrays such as HIRAX (Newburgh et al. 2016) and CHORD (Vanderlinde et al. 2019). Non-interferometric surveys have also been considered, such as BINGO (Battye et al. 2016; Wuensche et al. 2022), FAST (Hu et al. 2020) or using the SKA precursor MeerKAT (Wang et al. 2021). Intensity Mapping is also being used to search for signals from the EoR and the cosmic dawn, at redshifts above z ≳ 10, by several large radio-interferometers, such as LOFAR (van Haarlem et al. 2013), MWA (Tingay et al. 2013), HERA (DeBoer et al. 2017), and LWA (Eastwood et al. 2018). It is also planned to be used with SKA-low (Mondal et al. 2020).","Citation Text":["O’Connor et al. 2021"],"Citation Start End":[[1104,1124]]} {"Identifier":"2022MNRAS.517.4637PDeBoer_et_al._2017_Instance_1","Paragraph":"21 cm Intensity Mapping (IM) is a promising technique to map the cosmological large scale distribution of matter through the observation of 21 cm radio emission\/absorption of neutral hydrogen gas (H i), while not requiring the detection of individual sources (Bharadwaj, Nath & Sethi 2001; Battye, Davies & Weller 2004) and has been largely explored in the context of the search for the EoR (Epoch of Reionization) signal (Pritchard & Loeb 2008; Morales & Wyithe 2010). Subsequently, it was suggested that post-EoR 21 cm Intensity Mapping surveys could be used to constrain dark energy through the measurement of the Baryon Acoustic Oscillations (BAO) scale (Chang et al. 2008; Seo et al. 2010; Ansari et al. 2012) in the large scale structure (LSS) distribution, over a broad redshift range (z ≲ 6). Such surveys require instruments with large instantaneous bandwidth and field of view and several groups have built dense interferometric arrays to explore IM, such as CHIME (Bandura et al. 2014) or Tianlai (Chen 2012) in the last decade. Smaller instruments such as PAON4 (Ansari et al. 2020) and BMX (O’Connor et al. 2021) have also been built to explore specific technical aspects of these arrays, as well as transit mode operation and calibration. CHIME has proved to be a powerful fast radio burst and pulsar observation machine (The CHIME\/FRB Collaboration 2021) and has motivated the design and construction of larger, dish-based, dense interferometric arrays such as HIRAX (Newburgh et al. 2016) and CHORD (Vanderlinde et al. 2019). Non-interferometric surveys have also been considered, such as BINGO (Battye et al. 2016; Wuensche et al. 2022), FAST (Hu et al. 2020) or using the SKA precursor MeerKAT (Wang et al. 2021). Intensity Mapping is also being used to search for signals from the EoR and the cosmic dawn, at redshifts above z ≳ 10, by several large radio-interferometers, such as LOFAR (van Haarlem et al. 2013), MWA (Tingay et al. 2013), HERA (DeBoer et al. 2017), and LWA (Eastwood et al. 2018). It is also planned to be used with SKA-low (Mondal et al. 2020).","Citation Text":["DeBoer et al. 2017"],"Citation Start End":[[1965,1983]]} {"Identifier":"2016ApJ...819...40M__Luca_et_al._2011_Instance_1","Paragraph":"We found two nebulae associated with J2055, with angular dimensions of 12′ × 20″ and 250″ × 30″, respectively, for the brightest and faintest. The observed extensions of the nebulae, at a distance of 600 pc, would correspond to physical dimensions of ∼2.1 × 0.05 pc and ∼0.7 × 0.09 pc, respectively (assuming no inclination with respect to the plane of the sky). The luminosities of the nebulae in the 0.3–10 keV energy range (assuming d = 600 pc) are 1.2 × 1031 erg s−1 and 2.4 × 1030 erg s−1, corresponding to fractions of 2.4 × 10−3 and 3.0 × 10−4 of the pulsar spin-down luminosity. A few elongated tails of X-ray emission associated with rotation-powered pulsars have been discovered in the past (Gaensler et al. 2004; Becker et al. 2006; McGowan et al. 2006; Kargaltsev & Pavlov 2008b). Although for our pulsar we have no information about the proper motion, the bow-shock PWN scenario would seem the most natural explanation for one of the nebulae. Luminosity values are fully compatible with that measured for other synchrotron nebulae, for which the pulsars channel into their tails 10−2 to 10−4 of their rotational energy loss. In the case of synchrotron emission tails, if we assume the optimistic maximum Lorentz factor of ∼108 for electron acceleration in such a low-energetic pulsar magnetosphere and the high value of the ambient magnetic field of ∼50 μG (following considerations in De Luca et al. 2011), it is possible to estimate the synchrotron cooling time of the emitting electrons as \n\n\n\n\n\n (B\/50 μG)\n\n\n\n\n\n (E\/1 keV)\n\n\n\n\n\n yr. Coupling this value with the estimated physical length of the feature yields an estimate of the bulk flow speed of the emitting particles of ∼20,000 and 3000 km s−1, assuming no inclination with respect to the plane of the sky. The first value is only marginally consistent with results in the literature, while the second one is fully consistent (Kargaltsev & Pavlov 2008b). Taking into account the energetics, both nebulae are at least marginally consistent with a classical synchrotron nebula explanation. For classical synchrotron nebulae, we expect a relatively bright diffuse emission surrounding the pulsar, where the emission from the wind termination shock is brightest. The model of Gaensler & Slane (2006) predicts a low-scale termination shock of ∼06 fo J2055 (at 600 pc), thus not resolved by XMM-Newton, even in the case of typical ambient densities (0.01 atoms cm−3) and pulsar velocities (some hundreds of kilometers per second). In that case, part of the flux we assign to the pulsar comes instead from the termination shock (Kargaltsev & Pavlov 2008a). Along their main axis, the brightness profiles of both nebulae are consistent with an almost flat behavior, with a sudden decrease at the end. This is acceptable for synchrotron emission nebulae: in fact, the pulsar wind is more energetic in the surroundings of the pulsar, where the loss of energy through synchrotron emission is higher, decreasing in flux and energy along the pulsar trail. Taking also into account an inhomogeneous medium and\/or magnetic field, this behavior is expected, and it is observed for many objects in the literature (see, e.g., Kargaltsev & Pavlov 2008b). Such a synchrotron cooling of the particles injected at the termination shock induces a significant softening of the emission spectrum as a function of the distance from the pulsar in bow-shock PWNe. Taking into account the upper limit variation of the photon index we found, for the brightest tail of J2055 we do not have the predicted spectral variation. Classical theories of ram pressure particle confinement in pulsar tails are hardly put to the test by parsec-long nebulae, which would require much higher efficiencies than in all the other cases. The tightness of the main feature of J2055, if confirmed to be a synchrotron nebula from its shape and the pulsar motion, cannot be accounted for by any model in the literature. We conclude that the low energetics of the pulsar, the lack of any spatial-spectral variability, and the tightness of the brighter nebula disfavor the classical synchrotron emission nebula. This model can explain the characteristics of the secondary feature.","Citation Text":["De Luca et al. 2011"],"Citation Start End":[[1399,1418]]} {"Identifier":"2021ApJ...922..233O__Chatterjee_&_Cordes_2002_Instance_1","Paragraph":"The shape of the bow shock nose can be directly inferred from the Hα images and used to constrain the bow shock standoff radius. In the thin-shell limit, the radial shape of the bow shock can be expressed as (Wilkin 1996)\n7\n\n\n\n\nR\n\n(\nθ\n)\n\n=\n\n\nR\n\n\n0\n\n\n\ncsc\n\nθ\n\n\n3\n(\n1\n−\nθ\n\ncot\n\nθ\n)\n\n\n,\n\n\nwhere R0 is the standoff radius and θ represents the angle between the pulsar’s velocity and a point R(θ) along the bow shock. The standoff radius is dictated by the pressure balance between the ambient ISM and the neutron star wind and directly related to the interstellar density ρA, the pulsar wind velocity vw and mass-loss rate \n\n\n\n\n\n\n\n\nm\n\n\n\n\n\n\n\nw\n\n\n\n\n, and the pulsar velocity vp (Wilkin 1996):\n8\n\n\n\n\n\n\nR\n\n\n0\n\n\n=\n\n\n\n\n\n\n\n\n\n\n\nm\n\n\n\n\n\n\n\nw\n\n\n\n\nv\n\n\nw\n\n\n\n\n4\nπ\n\n\nρ\n\n\nA\n\n\n\n\nv\n\n\np\n\n\n2\n\n\n\n\n\n\n\n\n\n1\n\n\/\n\n2\n\n\n.\n\n\nEquation (8) assumes an isotropic stellar wind, which is not generally true of a relativistic neutron star wind. When the pulsar rotation vector is skewed relative to the pulsar proper motion and magnetic field, the pulsar wind will be quasi-isotropic, and its exact behavior will depend on both the orientations of these vectors and the opening angle of the wind. For B2224+65, the light-cylinder radius is significantly smaller than the bow shock standoff radius, suggesting that an isotropic wind is an adequate assumption without additional evidence for anisotropy (for a detailed discussion, see Chatterjee & Cordes 2002). Assuming that the spin-down energy loss is entirely carried by the relativistic wind, \n\n\n\n\n\n\n\n\nm\n\n\n\n\n\n\n\nw\n\n\n\n\nv\n\n\nw\n\n\n=\n\n\nE\n\n\n\n\n\n\n\/\n\nc\n\n\n. The standoff radius can be conveniently reformulated as an angle given by\n9\n\n\n\n\n\n\nθ\n\n\n0\n\n\n=\n56.3\n\nmas\n\n\n\n\n\n\n\nsin\n\n\n2\n\n\ni\n\n\n\n\nn\n\n\nA\n\n\n1\n\n\/\n\n2\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nE\n\n\n\n\n\n\n\n33\n\n\n1\n\n\/\n\n2\n\n\n\n\n\n\nμ\n\n\n100\n\n\n\n\nD\n\n\nkpc\n\n\n2\n\n\n\n\n\n\n\n,\n\n\nwhere i is the inclination angle, nA = ρA\/mH is the total number density of the interstellar hydrogen and helium mixture in atomic mass units per cubic centimeter, \n\n\n\n\n\n\nE\n\n\n\n\n\n\n\n is the spin-down luminosity in erg per second, D is the distance to the pulsar in kiloparsecs, and μ100 is the pulsar proper motion in 100 mas yr−1 (Chatterjee & Cordes 2002). The spin-down luminosity is \n\n\n\n\n\n\nE\n\n\n\n\n\n=\n4\n\n\nπ\n\n\n2\n\n\nI\n\n\nP\n\n\n\n\n\n\n\/\n\n\n\nP\n\n\n3\n\n\n\n\n, where I ≈ 1045 g cm2. The period derivative \n\n\n\n\n\n\nP\n\n\n\n\n\n\n\n can be corrected for the Schklovskii effect using\n10\n\n\n\n\n\n\nP\n\n\n\n\n\n=\n\n\n\n\nP\n\n\n\n\n\n\n\nobs\n\n\n−\n2.43\n×\n\n\n10\n\n\n−\n21\n\n\nP\n\n\nμ\n\n\nmasy\n\n\n2\n\n\n\n\nD\n\n\nkpc\n\n\n,\n\n\nwhere μmasy is the proper motion in milliarcseconds per year (Shklovskii 1970; Brownsberger & Romani 2014). This correction is negligible for B2224+65. The atomic number density nA is converted to an electron density ne assuming a cosmic abundance γH = 1.37, where nA = nHγH and nH ≈ ne. The standoff angle that is inferred from the outer edge of the Hα emission corresponds to a forward shock that lies slightly upstream of the contact discontinuity at an angular distance θa ≈ 1.3θ0 (Aldcroft et al. 1992; Bucciantini 2002). The period, period derivative, and spin-down luminosity for B2224+65 are shown in Table 1.","Citation Text":["Chatterjee & Cordes 2002"],"Citation Start End":[[1391,1415]]} {"Identifier":"2021ApJ...922..233O__Chatterjee_&_Cordes_2002_Instance_2","Paragraph":"The shape of the bow shock nose can be directly inferred from the Hα images and used to constrain the bow shock standoff radius. In the thin-shell limit, the radial shape of the bow shock can be expressed as (Wilkin 1996)\n7\n\n\n\n\nR\n\n(\nθ\n)\n\n=\n\n\nR\n\n\n0\n\n\n\ncsc\n\nθ\n\n\n3\n(\n1\n−\nθ\n\ncot\n\nθ\n)\n\n\n,\n\n\nwhere R0 is the standoff radius and θ represents the angle between the pulsar’s velocity and a point R(θ) along the bow shock. The standoff radius is dictated by the pressure balance between the ambient ISM and the neutron star wind and directly related to the interstellar density ρA, the pulsar wind velocity vw and mass-loss rate \n\n\n\n\n\n\n\n\nm\n\n\n\n\n\n\n\nw\n\n\n\n\n, and the pulsar velocity vp (Wilkin 1996):\n8\n\n\n\n\n\n\nR\n\n\n0\n\n\n=\n\n\n\n\n\n\n\n\n\n\n\nm\n\n\n\n\n\n\n\nw\n\n\n\n\nv\n\n\nw\n\n\n\n\n4\nπ\n\n\nρ\n\n\nA\n\n\n\n\nv\n\n\np\n\n\n2\n\n\n\n\n\n\n\n\n\n1\n\n\/\n\n2\n\n\n.\n\n\nEquation (8) assumes an isotropic stellar wind, which is not generally true of a relativistic neutron star wind. When the pulsar rotation vector is skewed relative to the pulsar proper motion and magnetic field, the pulsar wind will be quasi-isotropic, and its exact behavior will depend on both the orientations of these vectors and the opening angle of the wind. For B2224+65, the light-cylinder radius is significantly smaller than the bow shock standoff radius, suggesting that an isotropic wind is an adequate assumption without additional evidence for anisotropy (for a detailed discussion, see Chatterjee & Cordes 2002). Assuming that the spin-down energy loss is entirely carried by the relativistic wind, \n\n\n\n\n\n\n\n\nm\n\n\n\n\n\n\n\nw\n\n\n\n\nv\n\n\nw\n\n\n=\n\n\nE\n\n\n\n\n\n\n\/\n\nc\n\n\n. The standoff radius can be conveniently reformulated as an angle given by\n9\n\n\n\n\n\n\nθ\n\n\n0\n\n\n=\n56.3\n\nmas\n\n\n\n\n\n\n\nsin\n\n\n2\n\n\ni\n\n\n\n\nn\n\n\nA\n\n\n1\n\n\/\n\n2\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nE\n\n\n\n\n\n\n\n33\n\n\n1\n\n\/\n\n2\n\n\n\n\n\n\nμ\n\n\n100\n\n\n\n\nD\n\n\nkpc\n\n\n2\n\n\n\n\n\n\n\n,\n\n\nwhere i is the inclination angle, nA = ρA\/mH is the total number density of the interstellar hydrogen and helium mixture in atomic mass units per cubic centimeter, \n\n\n\n\n\n\nE\n\n\n\n\n\n\n\n is the spin-down luminosity in erg per second, D is the distance to the pulsar in kiloparsecs, and μ100 is the pulsar proper motion in 100 mas yr−1 (Chatterjee & Cordes 2002). The spin-down luminosity is \n\n\n\n\n\n\nE\n\n\n\n\n\n=\n4\n\n\nπ\n\n\n2\n\n\nI\n\n\nP\n\n\n\n\n\n\n\/\n\n\n\nP\n\n\n3\n\n\n\n\n, where I ≈ 1045 g cm2. The period derivative \n\n\n\n\n\n\nP\n\n\n\n\n\n\n\n can be corrected for the Schklovskii effect using\n10\n\n\n\n\n\n\nP\n\n\n\n\n\n=\n\n\n\n\nP\n\n\n\n\n\n\n\nobs\n\n\n−\n2.43\n×\n\n\n10\n\n\n−\n21\n\n\nP\n\n\nμ\n\n\nmasy\n\n\n2\n\n\n\n\nD\n\n\nkpc\n\n\n,\n\n\nwhere μmasy is the proper motion in milliarcseconds per year (Shklovskii 1970; Brownsberger & Romani 2014). This correction is negligible for B2224+65. The atomic number density nA is converted to an electron density ne assuming a cosmic abundance γH = 1.37, where nA = nHγH and nH ≈ ne. The standoff angle that is inferred from the outer edge of the Hα emission corresponds to a forward shock that lies slightly upstream of the contact discontinuity at an angular distance θa ≈ 1.3θ0 (Aldcroft et al. 1992; Bucciantini 2002). The period, period derivative, and spin-down luminosity for B2224+65 are shown in Table 1.","Citation Text":["Chatterjee & Cordes 2002"],"Citation Start End":[[2107,2131]]} {"Identifier":"2017MNRAS.469.3610T__Mészáros_et_al._1989_Instance_1","Paragraph":"In a pure scattering medium, the radiative transfer equations written in terms of the photon number intensity ni (i = O, X) take the form (see e.g. Alexander, Mészáros & Bussard 1989; Mészáros, Pavlov & Shibanov 1989)\n(15)\r\n\\begin{eqnarray}\r\n\\mu _z\\frac{\\mathrm{d}n_i}{\\mathrm{d}\\tau }&=& \\sum _{k=\\mathrm{O,X}}\\int \\bigg \\lbrace -\\sigma _{ik}(\\alpha \\rightarrow \\alpha ^{\\prime })n_i(\\alpha )\\left [1+n_k(\\alpha ^{\\prime })\\right] \\nonumber \\\\\r\n&&+ \\,\\sigma _{ki}(\\alpha ^{\\prime }\\rightarrow \\alpha )\\bigg (\\frac{\\varepsilon ^{\\prime }}{\\varepsilon }\\bigg )^2n_k(\\alpha ^{\\prime })\\left[1+n_i(\\alpha )\\right ]\\bigg \\rbrace \\mathrm{d}\\varepsilon ^{\\prime }\\mathrm{d}\\Omega ^{\\prime }, \r\n\\end{eqnarray}\r\nwhere stimulated scattering is accounted for. Here, dτ = neσTds is the infinitesimal Thomson depth, with s being a parameter along the photon propagation direction. However, the previous expression can be considerably simplified. In fact, in LTE, the scattering cross-sections (1) must obey the detailed balance condition (see e.g. Alexander et al. 1989; Mészáros et al. 1989; Alexander & Mészáros 1991):\n(16)\r\n\\begin{eqnarray}\r\n\\sigma _{ki}(\\alpha ^{\\prime }\\rightarrow \\alpha ) =\\bigg (\\frac{\\varepsilon }{\\varepsilon ^{\\prime }}\\bigg )^2\\exp \\left[-(\\varepsilon -\\varepsilon ^{\\prime })\/kT\\right]\\sigma _{ik}(\\alpha \\rightarrow \\alpha ^{\\prime })\\,;\r\n\\end{eqnarray}\r\nin this way, equation (15) becomes\n(17)\r\n\\begin{eqnarray}\r\n\\mu _z\\frac{\\mathrm{d}n_i}{\\mathrm{d}\\tau } &=& \\sum _{k=\\mathrm{O,X}}\\int \\bigg \\lbrace -\\sigma _{ik}(\\alpha \\rightarrow \\alpha ^{\\prime })n_i(\\alpha ) \\nonumber \\\\\r\n &&+ \\, \\sigma _{ik}(\\alpha \\rightarrow \\alpha ^{\\prime })F_i(\\alpha ,\\varepsilon ^{\\prime })n_k(\\alpha ^{\\prime })\\bigg \\rbrace \\mathrm{d}\\varepsilon ^{\\prime }\\mathrm{d}\\Omega ^{\\prime }, \r\n\\end{eqnarray}\r\nwhere\n(18)\r\n\\begin{eqnarray}\r\nF_i(\\alpha ,\\varepsilon ^{\\prime })\\equiv \\exp \\left [-(\\varepsilon -\\varepsilon ^{\\prime })\/kT\\right]\\left(1+n_i(\\alpha )\\right)-n_i(\\alpha ).\r\n\\end{eqnarray}\r\nFinally, under the assumption of conservative scattering (ε = ε΄) and substituting the expressions (1), one obtains\n(19)\r\n\\begin{eqnarray}\r\n\\mu _z\\frac{\\mathrm{d}n_\\mathrm{O}}{\\mathrm{d}\\tau } &=& -\\bigg [1-\\mu ^2_\\mathrm{Bk}+\\frac{3\\mu ^2_\\mathrm{Bk}}{4}\\bigg (\\frac{\\varepsilon }{\\varepsilon _\\mathrm{B}}\\bigg )^2\\bigg ]n_\\mathrm{O}(\\alpha ) \\nonumber \\\\\r\n&&+\\,\\frac{3}{8\\pi }\\int _{4\\pi }\\bigg [\\left(1-\\mu _\\mathrm{Bk}^2\\right)\\left(1-\\mu _\\mathrm{Bk}^{\\prime 2}\\right)n_\\mathrm{O}(\\alpha ^{\\prime }) \\nonumber \\\\\r\n&&+\\,\\bigg (\\frac{\\varepsilon }{\\varepsilon _\\mathrm{B}}\\bigg )^2\\mu ^2_\\mathrm{Bk}\\cos ^2\\left(\\phi _\\mathrm{Bk}-\\phi ^{\\prime }_\\mathrm{Bk}\\right)n_\\mathrm{X}(\\alpha ^{\\prime })\\bigg ]\\mathrm{d}\\Omega ^{\\prime }, \\nonumber \\\\\r\n\\ \\nonumber \\\\\r\n\\mu _z\\frac{\\mathrm{d}n_\\mathrm{X}}{\\mathrm{d}\\tau } &=& -\\bigg (\\frac{\\varepsilon }{\\varepsilon _\\mathrm{B}}\\bigg )^2n_\\mathrm{X}(\\alpha ) \\nonumber \\\\\r\n&&+ \\,\\frac{3}{8\\pi }\\bigg (\\frac{\\varepsilon }{\\varepsilon _\\mathrm{B}}\\bigg )^2\\int _{4\\pi }\\left[\\sin ^2\\left(\\phi _\\mathrm{Bk}-\\phi ^{\\prime }_\\mathrm{Bk}\\right)n_\\mathrm{X}(\\alpha ^{\\prime })\\right. \\nonumber \\\\\r\n&&\\left.+\\,\\mu ^{\\prime 2}_\\mathrm{Bk}\\cos ^2\\left(\\phi _\\mathrm{Bk}-\\phi ^{\\prime }_\\mathrm{Bk}\\right)n_\\mathrm{O}(\\alpha ^{\\prime })\\right]\\mathrm{d}\\Omega ^{\\prime }.\r\n\\end{eqnarray}\r\n","Citation Text":["Mészáros et al. 1989"],"Citation Start End":[[1075,1095]]} {"Identifier":"2020ApJ...895...35W__Tanimoto_et_al._2019_Instance_1","Paragraph":"To constrain the number density of the clump, getting the size of the clump (rc) should be required. The size of the self-gravitating clump in the context of AGNs has been estimated in the literature (e.g., Krolik & Begelman 1988; Hönig & Beckert 2007; Kawaguchi & Mori 2011). According to the authors of these works, we have rc ≤ 0.05 pc at 1 pc from the central SMBH with MBH = 8 × 108M⊙ (Scharwächter et al. 2013). On the other hand, the size of clumps can be constrained by the observations of transient X-ray absorption events in nearby AGNs, i.e., the typical size is 0.002 pc (e.g., Markowitz et al. 2014; Tanimoto et al. 2019). By adopting Nc and rc, taking into account their uncertainties of 3 ≤ Nc ≤ 15 and \n\n\n\n\n\n, the lower limit of number density of each ionized cloud \n\n\n\n\n\n can be given by\n8\n\n\n\n\n\nIn the case of ionized gas clumps, the typical Thomson scattering opacity of each cloud can be estimated as \n\n\n\n\n\n since the optical depth is given by \n\n\n\n\n\n, where σT is the Thomson cross section. If we adopt the opacity ratio of the dusty gas and the ionized gas is ≃103 at the UV band for the AGN radiation (e.g., Umemura et al. 1998; Ohsuga & Umemura 2001; Wada 2012), the optical depth of each cloud is \n\n\n\n\n\n, which is consistent with the lower value for nearby Seyfert galaxies (e.g., Table 10 in Ramos Almeida et al. 2011). This might indicate that the ionized gas is also clumpy within the 1 pc region of 3C 84. Wada et al. (2018) examine properties of the ionized gas irradiated by less luminous AGN such as Seyfert galaxies based on their “radiation-driven fountain” model (Wada 2012). They found that the ionized region show nonuniform internal structures, corresponding to the clumpy fountain flows caused by the radiation pressure on dusty gas, although the typical density (\n\n\n\n\n\n) is smaller than our estimate. In addition, by the optical\/NIR observations, the existence of dense clumps with \n\n\n\n\n\n cm−3 has been reported from the detection of coronal lines within NLR (e.g., Murayama & Taniguchi 1998). These high density clouds in NLRs might contribute the absorption feature of N1.","Citation Text":["Tanimoto et al. 2019"],"Citation Start End":[[613,633]]} {"Identifier":"2018MNRAS.481.5350S__Chiappini,_Matteucci_&_Romano_2001_Instance_1","Paragraph":"The origin of the Milky Way Galaxy presumably commenced within the initial one billion years (Gyr) subsequent to the Big Bang origin of the Universe around 13.7 Gyr ago. The formation of the Galaxy initiated with the merging of the initial diffuse neutral hydrogen gas clouds. This was followed by the gravitational merging of the colliding initial protogalaxies, thereby leading to the gradual accretional evolution of the galaxies in a hierarchical manner. The formation and evolution of the successive generations of stars inside the Galaxy led to the gradual abundance evolution of the elemental (and isotopic) inventories of the Galaxy. Galactic chemical evolution (GCE) models deal with understanding the origin of the distribution and gradual evolution of the elemental (and isotopic) abundances across the Galaxy over the Galactic time-scale of ∼13.7 Gyr (Matteucci and Franҫois 1989; Rana 1991; Chiappini, Matteucci & Gratton 1997; Pagel 1997; Chang et al. 1999; Goswami & Prantzos 2000; Alibés, Labay & Canal 2001; Chiappini, Matteucci & Romano 2001; Matteucci 2003, 2014; Franҫois et al. 2004; Kobayashi et al. 2006; Kobayashi and Nomoto 2009; Matteucci et al. 2009; Kobayashi and Nakasato 2011; Kobayashi, Karakas & Umeda 2011; Micali, Matteucci & Romano 2013; Minchev, Chiappini & Martig, 2013, 2014; Mott, Spitoni & Matteucci 2013; Sahijpal 2013, 2014; Sahijpal & Gupta 2013; Sahijpal 2014; Minchev et al. 2015; Spitoni et al. 2015). The astronomical observed trends in the elemental abundance distribution across the Galaxy serve as a major constraint on the GCE models in order to understand the accretional growth rate and the dynamical evolution of the Galaxy with its three main components, i.e. the Galactic halo, the thick disc, and the thin disc (Marochnik & Suchkov 1996; Matteucci 2003; Sparke & Gallagher 2007; Chiappini et al. 2015). The GCE model provides a detailed evolutionary account of the star formation rate (SFR), the average prevalent initial mass function (IMF) for star formation, the supernova (SN Ia, Ib\/c, II) rates, and the stellar nucleosynthetic contributions of stars with distinct mass and metallicity.","Citation Text":["Chiappini, Matteucci & Romano 2001"],"Citation Start End":[[1025,1059]]} {"Identifier":"2018MNRAS.481.5350SMatteucci_2003_Instance_1","Paragraph":"The origin of the Milky Way Galaxy presumably commenced within the initial one billion years (Gyr) subsequent to the Big Bang origin of the Universe around 13.7 Gyr ago. The formation of the Galaxy initiated with the merging of the initial diffuse neutral hydrogen gas clouds. This was followed by the gravitational merging of the colliding initial protogalaxies, thereby leading to the gradual accretional evolution of the galaxies in a hierarchical manner. The formation and evolution of the successive generations of stars inside the Galaxy led to the gradual abundance evolution of the elemental (and isotopic) inventories of the Galaxy. Galactic chemical evolution (GCE) models deal with understanding the origin of the distribution and gradual evolution of the elemental (and isotopic) abundances across the Galaxy over the Galactic time-scale of ∼13.7 Gyr (Matteucci and Franҫois 1989; Rana 1991; Chiappini, Matteucci & Gratton 1997; Pagel 1997; Chang et al. 1999; Goswami & Prantzos 2000; Alibés, Labay & Canal 2001; Chiappini, Matteucci & Romano 2001; Matteucci 2003, 2014; Franҫois et al. 2004; Kobayashi et al. 2006; Kobayashi and Nomoto 2009; Matteucci et al. 2009; Kobayashi and Nakasato 2011; Kobayashi, Karakas & Umeda 2011; Micali, Matteucci & Romano 2013; Minchev, Chiappini & Martig, 2013, 2014; Mott, Spitoni & Matteucci 2013; Sahijpal 2013, 2014; Sahijpal & Gupta 2013; Sahijpal 2014; Minchev et al. 2015; Spitoni et al. 2015). The astronomical observed trends in the elemental abundance distribution across the Galaxy serve as a major constraint on the GCE models in order to understand the accretional growth rate and the dynamical evolution of the Galaxy with its three main components, i.e. the Galactic halo, the thick disc, and the thin disc (Marochnik & Suchkov 1996; Matteucci 2003; Sparke & Gallagher 2007; Chiappini et al. 2015). The GCE model provides a detailed evolutionary account of the star formation rate (SFR), the average prevalent initial mass function (IMF) for star formation, the supernova (SN Ia, Ib\/c, II) rates, and the stellar nucleosynthetic contributions of stars with distinct mass and metallicity.","Citation Text":["Matteucci 2003"],"Citation Start End":[[1795,1809]]} {"Identifier":"2020MNRAS.499.3085Z__Kanekar_et_al._2003_Instance_1","Paragraph":"Most of these OH absorbers show an OH column density about the order of $10^{15} \\rm\\, cm^{-2}$. Gupta et al. (2018) show that galaxies with z 0.4 could have much lower OH column densities, i.e. below $10^{14} \\rm\\, cm^{-2}$, using a detected OH absorber and upper limits of eight non-detections and assuming the OH excitation temperature $T_x^{\\rm OH} = 3.5\\,$ K, however, a more commonly used $T_x^{\\rm OH}$ for OH absorbers at cosmological distances is 10 K (e.g. Kanekar & Chengalur 2002; Kanekar et al. 2003; Curran et al. 2011). The Gupta et al. (2018) sample contains only intervening absorbers with relatively low redshifts. Grasha et al. (2020) searched 11 intervening and five associated H i absorbers for OH absorptions and report no new detections except for a re-detection of the 1667 MHz OH absorption towards PKS 1830−211. Grasha et al. (2019) searched a large sample of compact radio sources for associated H i and OH absorptions but only six of them, which have relatively larger redshifts (z ∼ 0.6), have H i absorption detections and none of them have OH absorption detection. Intervening absorbers are mostly from foreground galaxies or H i dark clouds. Associated absorbers can be found in AGN outflows, circumnuclear discs, and cold gas clouds in the host galaxy or merger relics (Maccagni et al. 2017; Allison et al. 2019; Oosterloo et al. 2019). The cold molecular gas in these systems is not well studied due to a low detection number (Allison et al. 2019) and they could potentially have very different OH column densities and different excitation temperatures (Curran et al. 2016). Therefore, we observe a sample of low-redshift (z 0.3) galaxies with associated H i 21-cm absorption detections, with an extra target with a deep intervening H i 21-cm absorption for comparison, using the Five-hundred-meter Aperture Spherical radio Telescope (FAST; Nan et al. 2011; Li & Pan 2016; Li et al. 2018a; Jiang et al. 2020) aiming to study their cold gas parameters through OH absorptions.","Citation Text":["Kanekar et al. 2003"],"Citation Start End":[[494,513]]} {"Identifier":"2020MNRAS.495..600K__Dixon_1974_Instance_1","Paragraph":"In general, the time evolution of the PSR is governed by,\n(3)$$\\begin{eqnarray*}\r\n{T^{\\mu \\nu }}_{;\\nu } = 0,\r\n\\end{eqnarray*}$$where Tμν is the energy–momentum tensor. In the MPD formulation, a multipole expansion of the energy–momentum tensor is undertaken. This constructs the ‘gravitational skeleton’. In the extreme mass ratio limit, the pole and dipole terms are dominant and terms greater than the quadrupole can be neglected. The PSR dynamics are then entirely determined by the background gravitational field and the dynamical spin interaction with this field. The mass monopole is described by the 4-momentum pμ whilst the spin dipole is sμν. The corresponding equations of motion are (Mathisson 1937; Papapetrou 1951; Dixon 1974),\n(4)$$\\begin{eqnarray*}\r\n\\frac{D p^{\\mu }}{\\mathrm{ d} \\tau } = - \\frac{1}{2} {R^{\\mu }}_{\\nu \\alpha \\beta } u^{\\nu } s^{\\alpha \\beta },\r\n\\end{eqnarray*}$$(5)$$\\begin{eqnarray*}\r\n\\frac{D s^{\\mu \\nu }}{\\mathrm{ d} \\tau } = p^{\\mu } u^{\\nu } -p^{\\nu } u^{\\mu },\r\n\\end{eqnarray*}$$for proper time parametrization τ along the PSR worldline zα(τ), D\/dτ denotes a covariant derivative whilst uν is the PSR 4-velocity and Rμναβ the Riemann curvature tensor. In order to first construct the gravitational skeleton requires first specifying a reference worldline with which to define the expansion. Typically, such a choice would be the worldline described by the centroid (centre of mass) of the body. However, in GR the centroid choice is observer-dependent. This uncertainty is evidenced in the system of equations (4) and (5), which is not a determinate set since there exist more unknowns than equations. This is related to the uncertainty in choosing a reference world line for the multipole expansion. Explicitly choosing an observer with respect to which the centre of mass is defined renders the system of equations determinate. Such a choice is known as the spin supplementary condition (SSC). For this work we adopt the Tulczyjew-Dixon (TD) condition which specifies the centroid to be that measured in zero 3-momentum frame:\n(6)$$\\begin{eqnarray*}\r\ns^{\\mu \\nu } p_{\\nu } = 0,\r\n\\end{eqnarray*}$$(Tulczyjew 1959; Dixon 1964). A key advantage of this SSC is that it specifies a unique worldline. In contrast, other choices of SSC are infinitely degenerate (for discussion, including application to EMRIs, see Babak, Gair & Cole 2014; Filipe Costa & Natário 2014). With this choice of SSC both the mass of the MSP,\n(7)$$\\begin{eqnarray*}\r\nm = \\sqrt{- p^{\\mu } p_{\\mu }}\r\n\\end{eqnarray*}$$and the scalar contraction of the spin vector\n(8)$$\\begin{eqnarray*}\r\ns = s^{\\mu } s_{\\mu }\r\n\\end{eqnarray*}$$are constants of the motion. In turn, the spin vector is a contraction of the spin tensor,\n(9)$$\\begin{eqnarray*}\r\ns_{\\mu } = -\\frac{1}{2m} \\epsilon _{\\alpha \\beta \\mu \\nu } p^{\\nu } s^{\\alpha \\beta }\r\n.\r\n\\end{eqnarray*}$$","Citation Text":["Dixon 1974"],"Citation Start End":[[729,739]]} {"Identifier":"2018AandA...620A.191B__Driel-Gesztelyi_(1997)_Instance_1","Paragraph":"To understand the physics of sunspots, one has to study their temporal evolution. Formation and decaying phases play an important role in sunspot evolution. We refer to Martínez Pillet (2002) for a review of decaying sunspot evolution. For a long time, it was only possible to study the decay of the morphological changes of the area of sunspots because of the lack of inversion codes to interpret full-Stokes measurements, although the magnetic flux is the more important parameter. Bumba (1963) found a linear decrease of the area of the sunspot with time. Martinez Pillet et al. (1993) confirmed this linear decay, but obtained a different coeffcient. In contrast, Petrovay & van Driel-Gesztelyi (1997) found a parabolic decay with a rate proportional to \n\n\n\n\n\nA\n(\nt\n)\n\n\n\n\n$ \\sqrt{A(t)} $\n\n\n, where A is the area of the spot. Linear decay rates of the areas of 32 sunspots are found by Chapman et al. (2003). Baumann & Solanki (2005) investigate the Greenwich sunspot group record, but they were not able to distinguish between a linear and a quadratic decay law. Hathaway & Choudhary (2008) publish an almost constant decay rate of 3.65μHemispheres day−1. Gafeira et al. (2014) study four sunspots and find an approximately linear decay of the areas similar for umbra and penumbra. In both studies, the decay rates are different for individual spots. Case studies resulting in a linear decrease of the magnetic flux during the decay phase are presented by Deng et al. (2007) and Verma et al. (2016). In the latter publication, the development of the area is non-monotonic. Sheeley et al. (2017) investigated the development of the magnetic flux in 36 sunspots, but not all of them were in the decaying phase. Some spots showed a nearly linear decay, but they found also indications of a bursty decay. In a 100 h numerical simulation of a mature sunspot, Rempel (2015) find a linear decay of the magnetic flux in the umbra for the last 80 h. The penumbral magnetic flux remained almost constant during this period.","Citation Text":["Petrovay & van Driel-Gesztelyi (1997)"],"Citation Start End":[[668,705]]} {"Identifier":"2022ApJ...935..135B__Bland-Hawthorn_et_al._2019_Instance_1","Paragraph":"Disk galaxies typically reveal out-of-equilibrium features due to incomplete equilibration. These may appear in the form of bars and spiral arms, which are large-scale perturbations in the radial and azimuthal directions, responsible for a slow, secular evolution of the disk. In the vertical direction, disks often reveal warps (Binney 1992). In the case of the Milky Way (MW) disk, which can be studied in much greater detail than any other system, recent data from astrometric and radial velocity surveys such as SEGUE (Yanny et al. 2009), RAVE (Steinmetz et al. 2006), GALAH (Bland-Hawthorn et al. 2019), LAMOST (Cui et al. 2012), and above all Gaia (Gaia Collaboration et al. 2016, 2018a, 2018b) have revealed a variety of additional vertical distortions. At large galactocentric radii (>10 kpc) this includes, among others, oscillations and corrugations (Xu et al. 2015; Schönrich & Dehnen 2018), and streams of stars kicked up from the disk that undergo phase mixing, sometimes referred to as “feathers” (e.g., Price-Whelan et al. 2015; Thomas et al. 2019; Laporte et al. 2022). Similar oscillations and vertical asymmetries have also been reported in the solar vicinity (e.g., Widrow et al. 2012; Williams et al. 2013; Yanny & Gardner 2013; Gaia Collaboration et al. 2018b; Quillen et al. 2018; Bennett & Bovy 2019; Carrillo et al. 2019). One of the most intriguing structures is the phase-space spiral discovered by Antoja et al. (2018) and studied in more detail in subsequent studies (e.g., Bland-Hawthorn et al. 2019; Li 2021; Li & Widrow 2021; Gandhi et al. 2022). Using data from Gaia DR2 (Gaia Collaboration et al. 2018a), Antoja et al. (2018) selected ∼900,000 stars within a narrow range of galactocentric radius and azimuthal angle centered around the Sun. When plotting the density of stars in the (z, v\n\nz\n)-plane of vertical position, z, and vertical velocity, v\n\nz\n, they noticed a faint, unexpected spiral pattern, which became more enhanced when color-coding the (z, v\n\nz\n)-“pixels” by the median radial or azimuthal velocities. The one-armed spiral makes two to three complete wraps, resembling a snail shell, and is interpreted as a signature of phase mixing in the vertical direction following a perturbation, which Antoja et al. (2018) estimate to have occurred between 300 and 900 Myr ago. More careful analyses in later studies (e.g., Bland-Hawthorn et al. 2019; Li 2021) have nailed down the interaction time to ∼500 Myr ago.","Citation Text":["Bland-Hawthorn et al. 2019"],"Citation Start End":[[580,606]]} {"Identifier":"2022ApJ...935..135B__Bland-Hawthorn_et_al._2019_Instance_2","Paragraph":"Disk galaxies typically reveal out-of-equilibrium features due to incomplete equilibration. These may appear in the form of bars and spiral arms, which are large-scale perturbations in the radial and azimuthal directions, responsible for a slow, secular evolution of the disk. In the vertical direction, disks often reveal warps (Binney 1992). In the case of the Milky Way (MW) disk, which can be studied in much greater detail than any other system, recent data from astrometric and radial velocity surveys such as SEGUE (Yanny et al. 2009), RAVE (Steinmetz et al. 2006), GALAH (Bland-Hawthorn et al. 2019), LAMOST (Cui et al. 2012), and above all Gaia (Gaia Collaboration et al. 2016, 2018a, 2018b) have revealed a variety of additional vertical distortions. At large galactocentric radii (>10 kpc) this includes, among others, oscillations and corrugations (Xu et al. 2015; Schönrich & Dehnen 2018), and streams of stars kicked up from the disk that undergo phase mixing, sometimes referred to as “feathers” (e.g., Price-Whelan et al. 2015; Thomas et al. 2019; Laporte et al. 2022). Similar oscillations and vertical asymmetries have also been reported in the solar vicinity (e.g., Widrow et al. 2012; Williams et al. 2013; Yanny & Gardner 2013; Gaia Collaboration et al. 2018b; Quillen et al. 2018; Bennett & Bovy 2019; Carrillo et al. 2019). One of the most intriguing structures is the phase-space spiral discovered by Antoja et al. (2018) and studied in more detail in subsequent studies (e.g., Bland-Hawthorn et al. 2019; Li 2021; Li & Widrow 2021; Gandhi et al. 2022). Using data from Gaia DR2 (Gaia Collaboration et al. 2018a), Antoja et al. (2018) selected ∼900,000 stars within a narrow range of galactocentric radius and azimuthal angle centered around the Sun. When plotting the density of stars in the (z, v\n\nz\n)-plane of vertical position, z, and vertical velocity, v\n\nz\n, they noticed a faint, unexpected spiral pattern, which became more enhanced when color-coding the (z, v\n\nz\n)-“pixels” by the median radial or azimuthal velocities. The one-armed spiral makes two to three complete wraps, resembling a snail shell, and is interpreted as a signature of phase mixing in the vertical direction following a perturbation, which Antoja et al. (2018) estimate to have occurred between 300 and 900 Myr ago. More careful analyses in later studies (e.g., Bland-Hawthorn et al. 2019; Li 2021) have nailed down the interaction time to ∼500 Myr ago.","Citation Text":["Bland-Hawthorn et al. 2019"],"Citation Start End":[[1502,1528]]} {"Identifier":"2022ApJ...935..135B__Bland-Hawthorn_et_al._2019_Instance_3","Paragraph":"Disk galaxies typically reveal out-of-equilibrium features due to incomplete equilibration. These may appear in the form of bars and spiral arms, which are large-scale perturbations in the radial and azimuthal directions, responsible for a slow, secular evolution of the disk. In the vertical direction, disks often reveal warps (Binney 1992). In the case of the Milky Way (MW) disk, which can be studied in much greater detail than any other system, recent data from astrometric and radial velocity surveys such as SEGUE (Yanny et al. 2009), RAVE (Steinmetz et al. 2006), GALAH (Bland-Hawthorn et al. 2019), LAMOST (Cui et al. 2012), and above all Gaia (Gaia Collaboration et al. 2016, 2018a, 2018b) have revealed a variety of additional vertical distortions. At large galactocentric radii (>10 kpc) this includes, among others, oscillations and corrugations (Xu et al. 2015; Schönrich & Dehnen 2018), and streams of stars kicked up from the disk that undergo phase mixing, sometimes referred to as “feathers” (e.g., Price-Whelan et al. 2015; Thomas et al. 2019; Laporte et al. 2022). Similar oscillations and vertical asymmetries have also been reported in the solar vicinity (e.g., Widrow et al. 2012; Williams et al. 2013; Yanny & Gardner 2013; Gaia Collaboration et al. 2018b; Quillen et al. 2018; Bennett & Bovy 2019; Carrillo et al. 2019). One of the most intriguing structures is the phase-space spiral discovered by Antoja et al. (2018) and studied in more detail in subsequent studies (e.g., Bland-Hawthorn et al. 2019; Li 2021; Li & Widrow 2021; Gandhi et al. 2022). Using data from Gaia DR2 (Gaia Collaboration et al. 2018a), Antoja et al. (2018) selected ∼900,000 stars within a narrow range of galactocentric radius and azimuthal angle centered around the Sun. When plotting the density of stars in the (z, v\n\nz\n)-plane of vertical position, z, and vertical velocity, v\n\nz\n, they noticed a faint, unexpected spiral pattern, which became more enhanced when color-coding the (z, v\n\nz\n)-“pixels” by the median radial or azimuthal velocities. The one-armed spiral makes two to three complete wraps, resembling a snail shell, and is interpreted as a signature of phase mixing in the vertical direction following a perturbation, which Antoja et al. (2018) estimate to have occurred between 300 and 900 Myr ago. More careful analyses in later studies (e.g., Bland-Hawthorn et al. 2019; Li 2021) have nailed down the interaction time to ∼500 Myr ago.","Citation Text":["Bland-Hawthorn et al. 2019"],"Citation Start End":[[2365,2391]]} {"Identifier":"2022ApJ...935..135BAntoja_et_al._(2018)_Instance_1","Paragraph":"Disk galaxies typically reveal out-of-equilibrium features due to incomplete equilibration. These may appear in the form of bars and spiral arms, which are large-scale perturbations in the radial and azimuthal directions, responsible for a slow, secular evolution of the disk. In the vertical direction, disks often reveal warps (Binney 1992). In the case of the Milky Way (MW) disk, which can be studied in much greater detail than any other system, recent data from astrometric and radial velocity surveys such as SEGUE (Yanny et al. 2009), RAVE (Steinmetz et al. 2006), GALAH (Bland-Hawthorn et al. 2019), LAMOST (Cui et al. 2012), and above all Gaia (Gaia Collaboration et al. 2016, 2018a, 2018b) have revealed a variety of additional vertical distortions. At large galactocentric radii (>10 kpc) this includes, among others, oscillations and corrugations (Xu et al. 2015; Schönrich & Dehnen 2018), and streams of stars kicked up from the disk that undergo phase mixing, sometimes referred to as “feathers” (e.g., Price-Whelan et al. 2015; Thomas et al. 2019; Laporte et al. 2022). Similar oscillations and vertical asymmetries have also been reported in the solar vicinity (e.g., Widrow et al. 2012; Williams et al. 2013; Yanny & Gardner 2013; Gaia Collaboration et al. 2018b; Quillen et al. 2018; Bennett & Bovy 2019; Carrillo et al. 2019). One of the most intriguing structures is the phase-space spiral discovered by Antoja et al. (2018) and studied in more detail in subsequent studies (e.g., Bland-Hawthorn et al. 2019; Li 2021; Li & Widrow 2021; Gandhi et al. 2022). Using data from Gaia DR2 (Gaia Collaboration et al. 2018a), Antoja et al. (2018) selected ∼900,000 stars within a narrow range of galactocentric radius and azimuthal angle centered around the Sun. When plotting the density of stars in the (z, v\n\nz\n)-plane of vertical position, z, and vertical velocity, v\n\nz\n, they noticed a faint, unexpected spiral pattern, which became more enhanced when color-coding the (z, v\n\nz\n)-“pixels” by the median radial or azimuthal velocities. The one-armed spiral makes two to three complete wraps, resembling a snail shell, and is interpreted as a signature of phase mixing in the vertical direction following a perturbation, which Antoja et al. (2018) estimate to have occurred between 300 and 900 Myr ago. More careful analyses in later studies (e.g., Bland-Hawthorn et al. 2019; Li 2021) have nailed down the interaction time to ∼500 Myr ago.","Citation Text":["Antoja et al. (2018)"],"Citation Start End":[[2243,2263]]} {"Identifier":"2022ApJ...935..135BThomas_et_al._2019_Instance_1","Paragraph":"Disk galaxies typically reveal out-of-equilibrium features due to incomplete equilibration. These may appear in the form of bars and spiral arms, which are large-scale perturbations in the radial and azimuthal directions, responsible for a slow, secular evolution of the disk. In the vertical direction, disks often reveal warps (Binney 1992). In the case of the Milky Way (MW) disk, which can be studied in much greater detail than any other system, recent data from astrometric and radial velocity surveys such as SEGUE (Yanny et al. 2009), RAVE (Steinmetz et al. 2006), GALAH (Bland-Hawthorn et al. 2019), LAMOST (Cui et al. 2012), and above all Gaia (Gaia Collaboration et al. 2016, 2018a, 2018b) have revealed a variety of additional vertical distortions. At large galactocentric radii (>10 kpc) this includes, among others, oscillations and corrugations (Xu et al. 2015; Schönrich & Dehnen 2018), and streams of stars kicked up from the disk that undergo phase mixing, sometimes referred to as “feathers” (e.g., Price-Whelan et al. 2015; Thomas et al. 2019; Laporte et al. 2022). Similar oscillations and vertical asymmetries have also been reported in the solar vicinity (e.g., Widrow et al. 2012; Williams et al. 2013; Yanny & Gardner 2013; Gaia Collaboration et al. 2018b; Quillen et al. 2018; Bennett & Bovy 2019; Carrillo et al. 2019). One of the most intriguing structures is the phase-space spiral discovered by Antoja et al. (2018) and studied in more detail in subsequent studies (e.g., Bland-Hawthorn et al. 2019; Li 2021; Li & Widrow 2021; Gandhi et al. 2022). Using data from Gaia DR2 (Gaia Collaboration et al. 2018a), Antoja et al. (2018) selected ∼900,000 stars within a narrow range of galactocentric radius and azimuthal angle centered around the Sun. When plotting the density of stars in the (z, v\n\nz\n)-plane of vertical position, z, and vertical velocity, v\n\nz\n, they noticed a faint, unexpected spiral pattern, which became more enhanced when color-coding the (z, v\n\nz\n)-“pixels” by the median radial or azimuthal velocities. The one-armed spiral makes two to three complete wraps, resembling a snail shell, and is interpreted as a signature of phase mixing in the vertical direction following a perturbation, which Antoja et al. (2018) estimate to have occurred between 300 and 900 Myr ago. More careful analyses in later studies (e.g., Bland-Hawthorn et al. 2019; Li 2021) have nailed down the interaction time to ∼500 Myr ago.","Citation Text":["Thomas et al. 2019"],"Citation Start End":[[1044,1062]]} {"Identifier":"2022ApJ...935..135BQuillen_et_al._2018_Instance_1","Paragraph":"Disk galaxies typically reveal out-of-equilibrium features due to incomplete equilibration. These may appear in the form of bars and spiral arms, which are large-scale perturbations in the radial and azimuthal directions, responsible for a slow, secular evolution of the disk. In the vertical direction, disks often reveal warps (Binney 1992). In the case of the Milky Way (MW) disk, which can be studied in much greater detail than any other system, recent data from astrometric and radial velocity surveys such as SEGUE (Yanny et al. 2009), RAVE (Steinmetz et al. 2006), GALAH (Bland-Hawthorn et al. 2019), LAMOST (Cui et al. 2012), and above all Gaia (Gaia Collaboration et al. 2016, 2018a, 2018b) have revealed a variety of additional vertical distortions. At large galactocentric radii (>10 kpc) this includes, among others, oscillations and corrugations (Xu et al. 2015; Schönrich & Dehnen 2018), and streams of stars kicked up from the disk that undergo phase mixing, sometimes referred to as “feathers” (e.g., Price-Whelan et al. 2015; Thomas et al. 2019; Laporte et al. 2022). Similar oscillations and vertical asymmetries have also been reported in the solar vicinity (e.g., Widrow et al. 2012; Williams et al. 2013; Yanny & Gardner 2013; Gaia Collaboration et al. 2018b; Quillen et al. 2018; Bennett & Bovy 2019; Carrillo et al. 2019). One of the most intriguing structures is the phase-space spiral discovered by Antoja et al. (2018) and studied in more detail in subsequent studies (e.g., Bland-Hawthorn et al. 2019; Li 2021; Li & Widrow 2021; Gandhi et al. 2022). Using data from Gaia DR2 (Gaia Collaboration et al. 2018a), Antoja et al. (2018) selected ∼900,000 stars within a narrow range of galactocentric radius and azimuthal angle centered around the Sun. When plotting the density of stars in the (z, v\n\nz\n)-plane of vertical position, z, and vertical velocity, v\n\nz\n, they noticed a faint, unexpected spiral pattern, which became more enhanced when color-coding the (z, v\n\nz\n)-“pixels” by the median radial or azimuthal velocities. The one-armed spiral makes two to three complete wraps, resembling a snail shell, and is interpreted as a signature of phase mixing in the vertical direction following a perturbation, which Antoja et al. (2018) estimate to have occurred between 300 and 900 Myr ago. More careful analyses in later studies (e.g., Bland-Hawthorn et al. 2019; Li 2021) have nailed down the interaction time to ∼500 Myr ago.","Citation Text":["Quillen et al. 2018"],"Citation Start End":[[1282,1301]]} {"Identifier":"2018ApJ...869..168D__Telloni_et_al._2015_Instance_1","Paragraph":"The spectral ratio method has some shortcomings, e.g., one has to assume that the transverse fluctuations consist of a slab component and a 2D component only, and that these two components have the same spectral shape over the wavenumber range considered. This is why new techniques have recently been developed to investigate the slab and 2D turbulence. In particular, Horbury et al. (2008) proposed a different approach: a local mean magnetic field can be defined, at any given time and scale, as the convolution between the instantaneous magnetic field B0 and a Gaussian function (normalized to unity) whose width is the scale of interest. Fluctuations at a particular scale and at a range of angles to the local mean magnetic field can be gathered to study the solar wind turbulence in that direction. To obtain an estimate for the component of the turbulence that might provide the largest contribution to the scattering of the electrons, most likely fluctuations with wavevectors nearly parallel to the magnetic field (i.e., the “slab” component) with which the electrons can interact resonantly, we apply the method of wavelet transforms (e.g., Bruno & Telloni 2015). Figure 11 shows the power spectral density of the z-component of the magnetic field during 2002 October 20 as a function of the angle between the orientations of the local mean magnetic field and the sampling direction. The angular distribution of the normalized magnetic helicity spectrum of the magnetic field fluctuations is presented in Figure 12. At wavenumbers around \n\n\n\n\n\n km−1 left- and right-handed polarized magnetic fluctuations, commonly associated with ion cyclotron waves and kinetic Alfvén waves, respectively (Podesta & Gary 2011; Telloni et al. 2015), are clearly resolved in quasi-perpendicular and quasi-parallel directions with respect to the local mean magnetic field. Figure 13 shows the total power spectral density, Pzz(k), of the Bz component computed by means of the wavelet transforms (black curve), which is in good agreement with the spectral density determined with the standard FFT method as described above. The red curve, which makes up ≈50% of the transverse power, shows our estimate for the slab component. It is obtained by integrating the angular distribution of power spectral density of Bz shown in Figure 11, between 0° and 10°, i.e., over the angle range where the magnetic field vector can be considered quasi-parallel to the radial direction. In other words, the slab component is obtained by averaging, at each scale, the power spectral density found at those time instants when the magnetic field and the velocity vectors are, at that particular scale, aligned within 10°. It is worth noting that, since the data points involved in these averages can be very few (in an Alfvénic fast wind, such as the one considered in the present analysis, the magnetic field vector is mostly perpendicular or highly oblique to the velocity vector), the uncertainty related to the averages can be very large. As for the spectral ratio test, the underlying assumption is that Pzz(k) consists of two disjoint parts—a slab component with \n\n\n\n\n\n and a 2D component with \n\n\n\n\n\n—and the more the real geometry of the fluctuations deviates from the above, the larger the uncertainty in the amount of the slab component will become. Nevertheless, the above method seems to provide the best estimate of the slab component of the solar wind fluctuations that can be provided by single-spacecraft measurements at the moment (e.g., Chen et al. 2010; Wicks et al. 2010). In the following, we adopt as a working hypothesis that a 50% slab component is responsible for the scattering of the electrons and we neglect effects of the magnetic helicity.","Citation Text":["Telloni et al. 2015"],"Citation Start End":[[1723,1742]]} {"Identifier":"2022ApJ...937..105Z__Zhang_2021a_Instance_1","Paragraph":"For Model A, which assumes the very broad component around 4450 Å as coming from the Balmer emission regions, the following model functions are included. A narrow plus a broad Gaussian function (second moment smaller or larger than 500 km s−1) G\nHβ, N\n([λ\n0, β\nN\n, σ\n\nβ\nN\n, f\n\nβ\nN\n]) (parameter λ\n0 and σ as central wavelength and second moment in units of angstrom) and G\nHβ, B\n([λ\n0, β\nB\n, σ\n\nβ\nB\n, f\n\nβ\nB\n]) are applied to describe the Hβ. Narrow and broad Gaussian functions G\nHγ,N\n([λ\n0, γ\nN\n, σ\n\nγ\nN\n, f\n\nγ\nN\n]) and G\nHγ, B\n([λ\n0, γ\nB\n, σ\n\nγ\nB\n, f\n\nγ\nB\n]) are applied to describe the Hγ. Two narrow Gaussian functions G\n\nc1([λ\n0, c1, σ\n\nc1, f\n\nc1])and G\n\nc2([λ\n0, c2, σ\n\nc2, f\n\nc2]) are applied to describe the core components of the [O iii]λ4959, 5007 Å doublet. Two broad Gaussian functions G\n\ne1([λ\n0, e1, σ\n\ne1, f\n\ne1]) and G\n\ne2([λ\n0, e2, σ\n\ne2, f\n\ne2]) are applied to describe the extended components of the [O iii] doublet (Greene & Ho 2005a; Shen et al. 2011; Zhang 2021a), considering probably spatially extended emission regions for the outflow-related extended [O iii] components as discussed in Zakamska et al. (2016). A broad and a narrow Gaussian functions G\n\nc3([λ\n0, c3, σ\n\nc3, f\n\nc3]) and G\n\ne3([λ\n0, e3, σ\n\ne3, f\n\ne3]) are applied to describe the core and the extended components of the [O iii]λ4363 Å. A power-law component \n\n\n\nA×λ4100ÅB\n\n is applied to describe the continuum emissions underneath the emission lines. When the model functions are applied, the following restrictions are accepted. First, the line flux and second moment of each Gaussian component are not smaller than zero. Second, ratios of the central wavelengths (in units of angstrom) and second moments (in units of angstrom) of G\nHβ, N\n to G\nHγ, N\n are fixed to be\n1\n\n\n\nλ0,γN4341.68Å=λ0,βN4862.68Åσ0,γN4341.68Å=σ0,βN4862.68Å,\n\nleading the narrow Balmer lines to have the same redshift and line widths. Third, ratios of the central wavelengths, second moments, and fluxes of G\n\nc1 to G\n\nc2 to G\n\nc3 are fixed to be\n2\n\n\n\nλ0,c15008.24Å=λ0,c24960.295Å=λ0,c34364.436Åσ0,c15008.24Å=σ0,c24960.295Å=σ0,c34364.436Åfc1=3×fc2(fc3free).\n\nFourth, the ratios of the central wavelengths, second moments, and fluxes of G\n\ne1 to G\n\ne2 to G\n\ne3 are fixed to be\n3\n\n\n\nλ0,e15008.24Å=λ0,e24960.295Å=λ0,e34364.436Åσ0,e15008.24Å=σ0,e24960.295Å=σ0,e34364.436Åfe1=3×fe2(fe3free).\n\nThe model parameters of G\nHγ, B\n and G\nHβ, B\n are free to model parameters, which will provide further clues to the origin of the very broad components around 4450 Å from Balmer emissions or from extended [O iii] emissions or other physical origins. Then, through the Levenberg–Marquardt least-squares minimization technique, the best-fitting results to the emission lines obtained using Model A can be well determined, and are shown in Figure 2 with χ\n2\/dof ∼ 0.88 (where χ\n2 and dof are the summed squared residuals for the best-fitting results and the degrees of freedom, respectively). Here, in order to show clearer results, the left panel of Figure 2 shows the best-fitting results to the emission lines around Hβ with a rest wavelength range from 4600–5400 Å, and the right panel of Figure 2 shows the best-fitting results for the emission lines around Hγ with the rest wavelength range from 4200–4600 Å.","Citation Text":["Zhang 2021a"],"Citation Start End":[[990,1001]]} {"Identifier":"2022MNRAS.513.3458B__Burger_&_Zavala_2021_Instance_1","Paragraph":"To be a feasible mechanism of cusp-core transformation, SNF needs to fulfill a number of conditions. First and foremost, the total energy that is released by supernovae has to be sufficient to unbind the DM halo’s central cusp (Peñarrubia et al. 2012). A secondary condition is that SNF needs to be impulsive, i.e. SN-driven gas outflows need to give rise to sizeable changes of the gravitational potential on time-scales which are shorter than the typical dynamical times of DM particles in the inner halo (Pontzen & Governato 2012; Burger & Zavala 2021). From the observational side, there is evidence that starbursts in bright dwarfs, and thus, their associated supernova cycles, happen on time-scales that are comparable to the typical dynamical times of those galaxies (Kauffmann 2014). However, observations still lack the time resolution required to resolve starburst cycles on the smaller dynamical time-scales of the low-mass MW dwarf spheroidals (Weisz et al. 2014). In general, the more energy is injected during a SNF cycle, the shorter the time is over which that energy is injected, and the more concentrated the baryonic mass is to the centre of the DM halo (Burger & Zavala 2021), the more efficient the SNF-induced cusp-core transformation will be. In hydrodynamic simulations of galaxy formation, the implementations of SNF are calibrated to the resulting structural properties of larger galaxies. Recent studies suggest that, in cosmological simulations, the efficiency of SNF at flattening the cusps of dwarf-size DM haloes is mainly determined by one model parameter, the gas density threshold for star formation (Benítez-Llambay et al. 2019; Dutton et al. 2020). In a given dwarf galaxy, larger star formation thresholds lead to more bursty star formation, more concentrated and impulsive feedback, and a stronger contribution of baryons to the central potential, and hence to enhanced core formation (Benítez-Llambay et al. 2019; Bose et al. 2019).","Citation Text":["Burger & Zavala 2021"],"Citation Start End":[[534,554]]} {"Identifier":"2022MNRAS.513.3458B__Burger_&_Zavala_2021_Instance_2","Paragraph":"To be a feasible mechanism of cusp-core transformation, SNF needs to fulfill a number of conditions. First and foremost, the total energy that is released by supernovae has to be sufficient to unbind the DM halo’s central cusp (Peñarrubia et al. 2012). A secondary condition is that SNF needs to be impulsive, i.e. SN-driven gas outflows need to give rise to sizeable changes of the gravitational potential on time-scales which are shorter than the typical dynamical times of DM particles in the inner halo (Pontzen & Governato 2012; Burger & Zavala 2021). From the observational side, there is evidence that starbursts in bright dwarfs, and thus, their associated supernova cycles, happen on time-scales that are comparable to the typical dynamical times of those galaxies (Kauffmann 2014). However, observations still lack the time resolution required to resolve starburst cycles on the smaller dynamical time-scales of the low-mass MW dwarf spheroidals (Weisz et al. 2014). In general, the more energy is injected during a SNF cycle, the shorter the time is over which that energy is injected, and the more concentrated the baryonic mass is to the centre of the DM halo (Burger & Zavala 2021), the more efficient the SNF-induced cusp-core transformation will be. In hydrodynamic simulations of galaxy formation, the implementations of SNF are calibrated to the resulting structural properties of larger galaxies. Recent studies suggest that, in cosmological simulations, the efficiency of SNF at flattening the cusps of dwarf-size DM haloes is mainly determined by one model parameter, the gas density threshold for star formation (Benítez-Llambay et al. 2019; Dutton et al. 2020). In a given dwarf galaxy, larger star formation thresholds lead to more bursty star formation, more concentrated and impulsive feedback, and a stronger contribution of baryons to the central potential, and hence to enhanced core formation (Benítez-Llambay et al. 2019; Bose et al. 2019).","Citation Text":["Burger & Zavala 2021"],"Citation Start End":[[1174,1194]]} {"Identifier":"2022MNRAS.513.3458BBenítez-Llambay_et_al._2019_Instance_1","Paragraph":"To be a feasible mechanism of cusp-core transformation, SNF needs to fulfill a number of conditions. First and foremost, the total energy that is released by supernovae has to be sufficient to unbind the DM halo’s central cusp (Peñarrubia et al. 2012). A secondary condition is that SNF needs to be impulsive, i.e. SN-driven gas outflows need to give rise to sizeable changes of the gravitational potential on time-scales which are shorter than the typical dynamical times of DM particles in the inner halo (Pontzen & Governato 2012; Burger & Zavala 2021). From the observational side, there is evidence that starbursts in bright dwarfs, and thus, their associated supernova cycles, happen on time-scales that are comparable to the typical dynamical times of those galaxies (Kauffmann 2014). However, observations still lack the time resolution required to resolve starburst cycles on the smaller dynamical time-scales of the low-mass MW dwarf spheroidals (Weisz et al. 2014). In general, the more energy is injected during a SNF cycle, the shorter the time is over which that energy is injected, and the more concentrated the baryonic mass is to the centre of the DM halo (Burger & Zavala 2021), the more efficient the SNF-induced cusp-core transformation will be. In hydrodynamic simulations of galaxy formation, the implementations of SNF are calibrated to the resulting structural properties of larger galaxies. Recent studies suggest that, in cosmological simulations, the efficiency of SNF at flattening the cusps of dwarf-size DM haloes is mainly determined by one model parameter, the gas density threshold for star formation (Benítez-Llambay et al. 2019; Dutton et al. 2020). In a given dwarf galaxy, larger star formation thresholds lead to more bursty star formation, more concentrated and impulsive feedback, and a stronger contribution of baryons to the central potential, and hence to enhanced core formation (Benítez-Llambay et al. 2019; Bose et al. 2019).","Citation Text":["Benítez-Llambay et al. 2019"],"Citation Start End":[[1635,1662]]} {"Identifier":"2022MNRAS.513.3458BBenítez-Llambay_et_al._2019_Instance_2","Paragraph":"To be a feasible mechanism of cusp-core transformation, SNF needs to fulfill a number of conditions. First and foremost, the total energy that is released by supernovae has to be sufficient to unbind the DM halo’s central cusp (Peñarrubia et al. 2012). A secondary condition is that SNF needs to be impulsive, i.e. SN-driven gas outflows need to give rise to sizeable changes of the gravitational potential on time-scales which are shorter than the typical dynamical times of DM particles in the inner halo (Pontzen & Governato 2012; Burger & Zavala 2021). From the observational side, there is evidence that starbursts in bright dwarfs, and thus, their associated supernova cycles, happen on time-scales that are comparable to the typical dynamical times of those galaxies (Kauffmann 2014). However, observations still lack the time resolution required to resolve starburst cycles on the smaller dynamical time-scales of the low-mass MW dwarf spheroidals (Weisz et al. 2014). In general, the more energy is injected during a SNF cycle, the shorter the time is over which that energy is injected, and the more concentrated the baryonic mass is to the centre of the DM halo (Burger & Zavala 2021), the more efficient the SNF-induced cusp-core transformation will be. In hydrodynamic simulations of galaxy formation, the implementations of SNF are calibrated to the resulting structural properties of larger galaxies. Recent studies suggest that, in cosmological simulations, the efficiency of SNF at flattening the cusps of dwarf-size DM haloes is mainly determined by one model parameter, the gas density threshold for star formation (Benítez-Llambay et al. 2019; Dutton et al. 2020). In a given dwarf galaxy, larger star formation thresholds lead to more bursty star formation, more concentrated and impulsive feedback, and a stronger contribution of baryons to the central potential, and hence to enhanced core formation (Benítez-Llambay et al. 2019; Bose et al. 2019).","Citation Text":["Benítez-Llambay et al. 2019"],"Citation Start End":[[1924,1951]]} {"Identifier":"2022MNRAS.516.4156D__Bharadwaj_&_Ali_2005_Instance_1","Paragraph":"Radio interferometric observations of the redshifted 21-cm signal directly measures the complex visibilities that are the Fourier components of the intensity distribution on the sky. The radio telescope typically has a finite beam that allows us to use the ‘flat-sky’ approximation. Ideally, the fields κ and δT are expanded in the basis of spherical harmonics. For convenience, we use a simplified expression for the angular power spectrum by considering the flat sky approximation whereby we can use the Fourier basis. Using this simplifying assumption, we may approximately write the cross-correlation angular power spectrum as (Dash & Guha Sarkar 2021)\n$$\\begin{eqnarray}\r\nC^{ T \\kappa }_\\ell &=& \\frac{1 }{\\pi (\\chi _2- \\chi _1)} \\sum _{\\chi _1}^{\\chi _2} \\frac{\\Delta \\chi }{\\chi ^2} ~ \\mathcal {A}_T (\\chi) \\mathcal {A}_\\kappa (\\chi) D_{+}^2 (\\chi) \\int _0^{\\infty } \\mathrm{ d}k_{\\parallel }\\\\\r\n&&\\times \\,\\left[ 1 + \\beta _T(\\chi) \\frac{k_{\\parallel }^2}{k^2} \\right] P (k),\r\n\\end{eqnarray}$$where $k = \\sqrt{k_{\\parallel }^2 + \\left(\\frac{\\ell }{\\chi } \\right)^2 }$, D+ is the growing mode of density fluctuations, and βT = f\/bT is the redshift distortion factor – the ratio of the logarithmic growth rate f and the bias function and bT(k, z). The redshift-dependent function $\\mathcal {A}_{T}$ is given by (Bharadwaj & Ali 2005; Datta, Choudhury & Bharadwaj 2007; Guha Sarkar et al. 2012)\n(6)$$\\begin{eqnarray}\r\n\\mathcal {A}_{T} = 4.0 \\, {\\rm {mK}} \\, b_{T} \\, {\\bar{x}_{\\rm H\\,{\\small I}}}(1 + z)^2\\left(\\frac{\\Omega _{b0} h^2}{0.02} \\right) \\left(\\frac{0.7}{h} \\right) \\left(\\frac{H_0}{H(z)} \\right) .\r\n\\end{eqnarray}$$The quantity bT(k, z) is the bias function defined as ratio of H i-21 cm power spectrum to dark matter power spectrum $b_T^2 = P_{\\mathrm{ H}\\,{\\small I}}(z)\/P(z)$. In the post-reionization epoch z 6, the neutral hydrogen fraction remains with a value ${\\bar{x}_{\\rm H\\,{\\small I}}} = 2.45 \\times 10^{-2}$ (adopted from Noterdaeme et al. 2009; Zafar et al. 2013). The clustering of the post-reionization H i is quantified using bT. On sub-Jean’s length, the bias is scale dependent (Fang et al. 1993). However, on large-scale the bias is known to be scale independent. The scale above which the bias is linear, is however sensitive to the redshift. Post-reionization H i bias is studied extensively using N-body simulations (Bagla et al. 2010; Guha Sarkar et al. 2012; Sarkar et al. 2016; Carucci, Villaescusa-Navarro & Viel 2017). These simulations demonstrate that the large-scale linear bias increases with redshift for 1 z 4 (Marín et al. 2010). We have adopted the fitting formula for the bias bT(k, z) as a function of both redshift z and scale k (Guha Sarkar et al. 2012; Sarkar et al. 2016) of the post-reionization signal as\n(7)$$\\begin{eqnarray}\r\nb_{T}(k,z) = \\sum _{m=0}^{4} \\sum _{n=0}^{2} c(m,n) k^{m}z^{n} .\r\n\\end{eqnarray}$$The coefficients c(m, n) in the fit function are adopted from Sarkar et al. (2016).","Citation Text":["Bharadwaj & Ali 2005"],"Citation Start End":[[1334,1354]]} {"Identifier":"2022ApJ...924....2B__Shajib_et_al._2020_Instance_1","Paragraph":"Relative time delays between multiple gravitationally lensed images provide a one-step distance anchor of the universe, and thus H\n0. This probe is independent of the local distance ladder and the sound-horizon-physics anchors of the CMB and large-scale structure probes. The method, known as the time-delay cosmography, has been proposed more than half a century ago to utilize the transient nature of supernovae (SNe) for measuring the time delays (Refsdal 1964). Time-delay cosmography was first applied by measuring the time delays of multiply lensed quasars with multiseason monitoring campaigns (e.g., Kundić et al. 1997; Schechter et al. 1997; Fassnacht et al. 2002; Tewes et al. 2013; Courbin et al. 2018; Millon et al. 2020a). The discovery of numerous lensed quasar systems, follow-up monitoring, high-resolution imaging, and precise spectroscopic observations have led to a precise measurement of H\n0 using seven multiply lensed quasars (Wong et al. 2020; Shajib et al. 2020; Millon et al. 2020b). These measurements assumed particular forms of the mass density profiles of the deflector galaxies. The mass-sheet degeneracy (MSD; see Falco et al. 1985; Schneider & Sluse 2013), an inherent transform leaving the lensing observables invariant while changing the time-delay prediction, poses limits in the precision of H\n0 measurements in the absence of additional data. Birrer et al. (2020) introduced an additional degree of freedom to the mass density profiles to avoid constraining the lens model based on the specific form of the mass profiles previously chosen. Birrer et al. (2020) constrained the MSD solely by stellar kinematics observations of the deflector galaxy hierarchically on the deflector population-level mitigating covariances among the assumptions of individual lenses. For the achieved 5% precision measurement of H\n0, Birrer et al. (2020) combined the seven TDCOSMO lenses with 33 galaxy–galaxy lenses from the Sloan Lens ACS (SLACS) survey (Bolton et al. 2008; Shajib et al. 2021). The interpretation of the kinematics measurements is impacted by the mass-anisotropy degeneracy (Binney & Mamon 1982; Dejonghe & Merritt 1992), and mitigating this degeneracy requires assumption on the stellar anisotropy distribution or spatially resolved kinematics measurements (e.g., Cappellari 2008; Barnabè et al. 2011; Yıldırım et al. 2020). A forecast for future constraints using kinematics observations in breaking the MSD within the assumptions of the Birrer et al. (2020) analysis is provided by Birrer & Treu (2021).","Citation Text":["Shajib et al. 2020"],"Citation Start End":[[967,985]]} {"Identifier":"2017MNRAS.466..194B__Zdziarski_1995_Instance_1","Paragraph":"Some fraction of the Comptonized photons will be intercepted by the disc and reflected into the line of sight by further Compton scattering and florescence. These processes give rise to a complex spectral component that typically peaks at energies of 3050keV (the so-called Compton hump, see Sunyaev Titarchuk 1980, figs 10a and c) and adds further fluorescent emission to the spectrum. The reflection component is present in both BH XBs (due to interaction of X-rays with the accretion disc and the surface of the normal star; Basko, Sunyaev Titarchuk 1974) and active galactic nuclei (AGNs; Nandra Pounds 1994), and complicates attempts to understand the dominant Comptonized emission owing to proximity of the Compton hump to the plausible location of the high-energy turn-off (corresponding to 3kTe). Typical attempts to take reflection into account involve adding sophisticated reflection components (such as the xspec models pexrav (Magdziarz Zdziarski 1995) or reflionx (Ross Fabian 2005)) to unsophisticated models of Comptonization, such as a cut-off power law. This inaccurate representation of the Comptonization means that interesting properties such as the electron temperature or Compton y-parameter are then inferred from the best fit of a cut-off power law to the data, rather than a direct treatment of these quantities. In addition to this, Ibragimov etal. (2005) showed that the strength of the reflected component R (defined in terms of the solid angle subtended by the portion of the disc in line of sight to the corona) is systematically overestimated by such treatment. It has been known for some time that R correlates strongly with photon index (Gilfanov, Churazov Revnivtsev 1999; Revnivtsev, Gilfanov Churazov 2001; Ibragimov etal. 2005), increasing as spectra become softer (implying a decreasing y-parameter). Similar behaviour has been observed for AGN spectra (Zdziarski, Lubiski Smith 1999; Gilfanov, Churazov Revnivtsev 2000; Zdziarski etal. 2003). This relationship clearly favours the accretion disc as the source of the seed photons for Comptonization, as the radiation being intercepted by the disc is increasing in tandem with the seed photon flux incident on the electron cloud. However, there is increasing evidence that at lower luminosities synchrotron photons from the magnetized corona may contribute a significant, perhaps dominant, population of seed photons, motivating the creation of so-called hybrid models. Such models typically comprise both a low-energy thermal population and an additional high-energy non-thermal population of electrons (see, e.g. Coppi 1999; Merloni Fabian 2001; Del Santo etal. 2013).","Citation Text":["Magdziarz Zdziarski 1995"],"Citation Start End":[[942,967]]} {"Identifier":"2018ApJ...866L..15T__Štěpán_et_al._2018_Instance_1","Paragraph":"The line-center photons of the hydrogen Lyα line originate just at the boundary of the model’s TR. In a 1D model atmosphere (e.g., Fontenla et al. 1993), the vector normal to the TR lies along the vertical, which coincides with the symmetry axis of the incident radiation field. In a 3D model atmosphere (e.g., Carlsson et al. 2016), the model’s TR delineates a corrugated surface, so that the vector normal to the model’s TR changes its direction from point to point (see Figure 7 of Štěpán et al. 2015). On the other hand, at each point on such corrugated surface the stratification of the physical quantities along the local normal vector \n\n\n\n\n\n is much more important than along the perpendicular direction. In order to estimate how the line-center fractional polarization of the hydrogen Lyα line is at each point of the field of view, it is reasonable to assume that the incident radiation field has axial symmetry around the direction of the normal vector \n\n\n\n\n\n corresponding to the spatial point under consideration (see also Štěpán et al. 2018). Taking a reference system with the Z-axis directed along the normal vector \n\n\n\n\n\n, and recalling Equation (1), at each point of the corrugated TR surface we can estimate the line-center fractional polarization signals through the following formula\n2\n\n\n\n\n\nwhere the positive Stokes Q reference direction is now the perpendicular to the plane formed by \n\n\n\n\n\n and the LOS, \n\n\n\n\n\n is the cosine of the angle between \n\n\n\n\n\n and the LOS, and \n\n\n\n\n\n is the anisotropy factor calculated in the new reference system. Clearly, because the direction of \n\n\n\n\n\n changes as we move through the corrugated surface that delineates the TR, the Q\/I signals estimated with Equation (2) do not share the same reference direction for the quantification of the linear polarization. In order to arrive at equations for Q\/I and U\/I having the parallel to the nearest limb as the positive Stokes Q reference direction, we have applied suitable rotations of the reference system. Specifying the direction of the local TR normal vector through its inclination \n\n\n\n\n\n with respect to the vertical (with \n\n\n\n\n\n between 0° and 90°) and azimuth \n\n\n\n\n\n (with \n\n\n\n\n\n between 0° and 360°), our analytical calculations show that the line-center Q\/I and U\/I signals of the hydrogen Lyα line can be estimated by the following formulas:\n3\n\n\n\n\n\n\n\n4\n\n\n\n\n\nFigure 2 shows examples of CLV of the Q\/I and U\/I Lyα line-center signals for several topologies of the model’s TR, with random azimuth \n\n\n\n\n\n. The first three rows of the figure correspond to the indicated fixed inclinations \n\n\n\n\n\n, while the bottom row panels show the case in which also \n\n\n\n\n\n has random values (i.e., the probability distribution \n\n\n\n\n\n for \n\n\n\n\n\n and \n\n\n\n\n\n for \n\n\n\n\n\n). Note that the CLV of the fractional linear polarization line-center signals is very sensitive to the geometry of the model’s TR, and that there is no CLV at all when the normal vector \n\n\n\n\n\n has random orientations. Moreover, it is also very important to point out that the Q\/I and U\/I amplitudes are sensitive to the magnetic field strength of the chromosphere-corona TR, through the Hanle factor \n\n\n\n\n\n in Equations (3) and (4).","Citation Text":["Štěpán et al. 2018"],"Citation Start End":[[1035,1053]]} {"Identifier":"2018ApJ...865...36P__Sancisi_et_al._2008_Instance_1","Paragraph":"Accretion of diffuse gas onto the disks of galaxies from the intergalactic medium (IGM) is a possible explanation for how the H i content of galaxies has remained relatively constant since z ∼ 2 while the star formation rate (SFR) was up to 10 times higher at high redshifts (Noterdaeme et al. 2012; Madau & Dickinson 2014). The constant H i content implies that galaxies have somehow replenished themselves with enough gas to fuel continuous star formation. And though not directly responsible for star formation, H i is an intermediate phase toward molecular hydrogen, which is the raw ingredient of the star formation fuel. If the star formation is to continue, external gas has to be accreted and pass through the H i phase at some stage in the accretion process. Observationally inferred accretion rates as traced by H i, however, fall between 0.1 and 0.2 \n\n\n\n\n\n at low redshifts. This is a full order of magnitude lower than what is needed for galaxies to continually form stars at their current rates (Sancisi et al. 2008; Kauffmann et al. 2010). This discrepancy presents two intriguing scenarios: the cycle of star formation will eventually exhaust all of the available fuel within a few Gyr and star formation itself will gradually cease, or processes that refuel galaxies with the necessary gas have been missed by previous surveys. Numerical simulations have shown a likely mechanism for refueling star formation is through a quasi-spherical “hot” mode and filamentary “cold” mode (Birnboim & Dekel 2003; Kereš et al. 2005, 2009). “Cold” in the context of these numerical simulations refers to gas that has not been heated above the virial temperature of the galaxy’s potential well (∼105 K), and “hot” refers to gas that has virialized in a process akin to the classical theory of galaxy formation in which shock-heated, virialized gas with short cooling timescales accretes onto the central galaxy (e.g., Rees & Ostriker 1977). These simulations also suggest cold mode accretion was the dominant form of accretion at z ≥ 1 for all systems, and remains prevalent through z = 0 for galaxies in low-density environments (ngal ≲1 h3 Mpc−3) and Mhalo ≲ 1011.4 \n\n\n\n\n\n (or Mbary ≤ 1010.3 \n\n\n\n\n\n). For perspective, our own Milky Way has a virial (and thus halo) mass on the order of 1012 \n\n\n\n\n\n. These cold flows should exist in the form of vast filaments of cold, diffuse gas that permeate through the hot halo (Kereš et al. 2005). Comparisons by Nelson et al. (2013) between the smoothed particle hydrodynamic (SPH) numerical scheme employed in Kereš et al. (2005, 2009) and more sophisticated adaptive mesh refinement (AMR) simulations revealed the relative contribution of the cold mode is likely overestimated in earlier SPH simulations due to inherent numerical deficiencies. Nevertheless, the AMR simulations do show some fraction of gas is accreted cold.","Citation Text":["Sancisi et al. 2008"],"Citation Start End":[[1009,1028]]} {"Identifier":"2020MNRAS.492.2481W__Murchikova_et_al._2019_Instance_1","Paragraph":"With the ALMA results, we now estimate such physical parameters as the temperature, density, and volume filling factor of warm ionized gas in the IRS 13E region. Assuming that that this gas is under the local thermodynamic equilibrium and its 232 GHz continuum and H30α line emissions are optically thin, the electron temperature Te can be expressed as\n(4)$$\\begin{eqnarray*}\r\nT_{\\rm e}({\\rm K}) &=& \\left[ \\frac{6985}{\\alpha (\\nu ,T_{\\rm e})} \\left(\\frac{\\nu }{\\rm GHz}\\right)^{1.1} \\frac{1}{1+N({\\rm He})\/N({\\rm H})}\\right. \\nonumber\\\\\r\n&&\\left.\\times \\, \\left(\\frac{S_{\\rm C}}{S\\Delta V_{\\rm H30\\alpha }} \\right) \\right]^{0.87},\r\n\\end{eqnarray*}$$where the elemental number density ratio of $N({\\rm He})\/N(\\rm H) \\sim 0.08$ and α(ν, Te) ∼ 0.85 at ν = 232 GHz and Te ∼ 104 K (Mezger & Henderson 1967). For E3, the total flux densities of the continuum and H30α line emissions are SC = 28.5 ± 1.8 mJy and SΔVH30α = 2.37 ± 0.12 Jy km s−1. We thus have Te = 9260 ± 650 K, which is consistent with previous estimates, ranging from 6000 to 12 000 K (Zhao et al. 2010; Moser et al. 2017; Tsuboi et al. 2019). We can also obtain the volume emission measure (EM) as (Murchikova et al. 2019)\n(5)$$\\begin{eqnarray*}\r\n{\\rm EM} = S\\Delta V_{\\rm H30\\alpha }\\frac{4\\pi D^2}{\\epsilon _{\\rm H30\\alpha }(T_{\\rm e},n_{\\rm e})} \\frac{\\nu }{c} \\sim 1 \\times 10^{60}\\rm ~cm^{-3},\r\n\\end{eqnarray*}$$where the H30α emissivity $\\epsilon _{\\rm H30\\alpha }=1.25\\times 10^{-31} \\rm ~erg~s^{-1}$ for Te = 104 K and $n_{\\rm e}=10^4\\sim 10^7 \\rm ~cm^{-3}$ (Storey & Hummer 1995) and the speed of light c are used. Furthermore, we find that both the continuum and H30α emission intensities of E3 can be characterized by a Gaussian with a deconvolved size of ∼0.01 pc, assuming a spherical symmetry. This together with the above EM value leads to the estimate of $n_{\\rm e} \\sim 3 \\times 10^5\\rm ~cm^{-3} f_V^{-1\/2}$. By further assuming a thermal pressure balance between the warm and hot gases (e.g. P\/k ∼ 2 × 1010 K cm−3; Section 3.2), we estimate the volume filling factor fV ∼ 0.1 and hence $n_{\\rm e} \\sim 10^6\\rm ~cm^{-3}$. If similar temperature and pressure could be assumed for warm ionized gas on larger scales, its filling factor has to be very small. We estimate that the total H30α flux within a circular region of 1 arcsec radius centred on E3 (Fig. 7B) is ${\\sim}12 \\rm ~Jy~km~s^{-1}$, which corresponds to ${\\rm EM} = 6\\times 10^{60}\\rm ~cm^{-3}$. The filling factor is then ∼8 × 10−4, while the mass of the warm ionized gas in this region is ∼mpEM\/ne ∼ 1 × 10−2 M⊙. These estimates indicate that the volume is indeed dominated by hot gas and that warm gas traces dense clumps, probably their surfaces exposed to the ionizing radiation from massive stars in the region.","Citation Text":["Murchikova et al. 2019"],"Citation Start End":[[1177,1199]]} {"Identifier":"2019ApJ...887L..14B__Hauschildt_et_al._1999_Instance_1","Paragraph":"Still, to further rule out a stellar origin, we attempt to fit the transit spectrum with a stellar contamination model. Following Rackham et al. (2018) we consider the hypothesis that the observed transit depth variations are due to inhomogeneities on the stellar surface. The observed wavelength-dependent transit depths \n\n\n\n\n\n\nD\n\n\nλ\n,\nobs\n\n\n\n\n are modeled as:\n4\n\n\n\n\n\n\nD\n\n\nλ\n,\nobs\n\n\n=\n\n\n\n\n\nD\n\n\nλ\n\n\n\n\n1\n−\n\n\nf\n\n\nspot\n\n\n\n\n\n1\n−\n\n\n\n\n\nF\n\n\nλ\n,\nspot\n\n\n\n\n\n\nF\n\n\nλ\n,\nphot\n\n\n\n\n\n\n\n\n−\n\n\nf\n\n\nfac\n\n\n\n\n\n1\n−\n\n\n\n\n\nF\n\n\nλ\n,\nfac\n\n\n\n\n\n\nF\n\n\nλ\n,\nphot\n\n\n\n\n\n\n\n\n\n\n\n,\n\n\nwhere Dλ is the geometric radius ratio \n\n\n\n\n\n\n\n\n\n\nR\n\n\np\n\n\n\n\/\n\n\n\nR\n\n\n⋆\n\n\n\n\n\n\n2\n\n\n\n\n, assumed here to be constant with wavelength (=D), fspot and ffac are the spot and faculae covering fractions, and the Fλ refer to bandpass-integrated PHOENIX model spectra of the photosphere, spots, and faculae (Hauschildt et al. 1999). Using K2-18b stellar parameters (Table 2), we explore a wide range of possible stellar contamination spectra for M2–M3 stars with spot and faculae covering fractions consistent with 1% I-band variability. Based on Rackham et al. (2018), we then explore scenarios with giant spots and solar-like spots as well as with and without faculae, resulting in spot fractions of up to 20%. However, none of those models can explain the amplitude of the observed transit spectrum. The amplitude of resulting transit depth variations due to the stellar inhomogeneities are up to 3–8 parts-per-million (ppm), about an order of magnitude smaller than the observed 80–90 ppm transit depth variations in the observed WFC3 spectrum (Figure 3). Finally, we also explore the most extreme scenarios where the spot and faculae covering fractions can be as high as 100%, but even those stellar inhomogeneity models fail to explain the amplitude of the observed transit depth variation. They deliver an absolute maximum of 20 ppm at 1.4 μm, which still only corresponds to less than a quarter of the transit depth variation in the observations. We conclude that stellar inhomogeneities and activity cannot explain the measured transmission spectrum.","Citation Text":["Hauschildt et al. 1999"],"Citation Start End":[[838,860]]} {"Identifier":"2016ApJ...827...93N__Zucker_et_al._2004_Instance_1","Paragraph":"The results presented in this work answer a number of questions regarding the character of the GG Tau A system, while raising others and leaving others untouched. First among the questions raised by our results are the questions of whether the detailed morphology of features in the circumbinary torus as seen in our simulations are actually present in the GG Tau A system. The current best resolution observations of the torus provide tantalizing hints that such features do exist, but a definitive statement that such features are present must await higher resolution observations of quality similar to those described by the ALMA Partnership (2015), for the HL Tau circumstellar disk. Another important question concerns planet formation in multiple systems. Whether or not any theoretical mechanism presently exists to explain the formation of giant planets in binary systems, the fact remains that at least a few binary systems, such as γ Cephei (Neuhauser et al. 2007), GI86 (Queloz et al. 2000), and HD 41004 (Zucker et al. 2004), do harbor planets. Therefore, some formation mechanism does in fact exist. While we find that accretion into the circumstellar disks occurs rapidly enough so that they can survive for the comparatively long timescales needed to form planets, other conditions, such as temperatures, remain quite unfavorable. What are the mechanisms still missing from our models that permit such objects to form? Finally, our simulations model the evolution of the “A” component of the full GG Tau system over a time span extending over only a tiny fraction of its formation timescale and in only two spatial dimensions. We neglected the full dynamical effects expected to be present in the system, insofar as our results include neither the distant binary “B” component of the GG Tau system, nor the newly discovered tight binary nature of the GG Tau Ab component. Even so, we find large scale morphological changes even over this short time span, and restricted dimensionality and physical system. Given the vigor of the activity over such a short timescale, we would expect activity of similar scale to occur over longer time spans as well, with correspondingly large consequences on the system morphology. To what extent will 3D effects also play a role in the evolution? What will be the end state configuration of the GG Tau system as a whole? Will the components eventually break apart? Merge? Future investigations extending the work presented here will be required in order to answer these questions.","Citation Text":["Zucker et al. 2004"],"Citation Start End":[[1017,1035]]} {"Identifier":"2017ApJ...840..118L__Mu_et_al._2016_Instance_5","Paragraph":"Our formula can be used to confront the curvature effect with observations and estimate the decay timescale of the steep decay phase. In observations, the steep decay phase has been observed in the decay phase of the prompt emission phase and flares in GRBs. Since the value of E0 (\n\n\n\n\n∼\n0.3\n–\n1\n\nMeV\n\n\n) in the prompt emission phase is significantly larger than \n\n\n\n\n10\n\nkeV\n\n\n, the β in the steep decay phase of prompt emission would be a linear function of observer time based on Equation (38). This behavior has been observed in a number of bursts, such as GRBs 050814 (Zhang et al. 2009, please see the spectral evolution in the \n\n\n\n\nβ\n−\n\n\nt\n\n\nobs\n\n\n\n\n space), 051001 etc. The linear relation between β and \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n is also found in the steep decay of flares (e.g., Mu et al. 2016). For a linear function β of \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n, one can obtain the slope of the linear function, which is equal to \n\n\n\n\n7.9\n\n\nκ\n\n\nˆ\n\n\n\n\/\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n2.37\n\nkeV\n\n\/\n\n[\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n]\n\n\n based on Equations (38) or (39). Then, the decay timescale \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n of our studying phase can be estimated if the value of \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n is known. We fit the spectral evolution in the decay phase of a flare (\n\n\n\n\n∼\n172\n\ns\n\n\n) in GRB 060904B (Mu et al. 2016) with a linear function. The fitting result, i.e., \n\n\n\n\nβ\n=\n0.84\n+\n0.020\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n with \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n\n\nt\n\n\nobs\n\n\n−\n\n\nt\n\n\np\n\n\n\n\n, is shown in the left panel of Figure 4 with a red solid line. Then, we have \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n119\n\nkeV\n\ns\n\n\n, which is around that found in Mu et al. (2016), i.e., \n\n\n\n\n2.54\n\nkeV\n×\n65.39\n\ns\n\n\n. For a flare (\n\n\n\n\n∼\n116\n\ns\n\n\n) in GRB 131030A, the spectrum at the beginning of the steep decay phase can be fitted with a Band function. With the fitting result found in Mu et al. (2016), i.e., \n\n\n\n\n\n\nα\n\n\nˆ\n\n\n=\n−\n0.91\n\n\n, \n\n\n\n\n\n\nβ\n\n\nˆ\n\n\n=\n−\n3.19\n\n\n, and \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n=\n1.95\n\n\n, we plot the evolution of β based on Equation (38) in the right panel of Figure 4 with a red solid line. Here, we adopt \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n54\n\ns\n\n\n (Mu et al. 2016), which can also be roughly estimated based on the flux evolution. It can be found that Equation (38) describes the spectral evolution approximately, which may reveal that a more appropriate value of parameters (e.g., \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n) may be required for this source. The agreement of our analytical formula and observational data shows that the assumption (2) given at the beginning of Section 2 (i.e., the jet shell has no θ-dependent spectral parameters or Lorentz factor) is applicable in reality.","Citation Text":["Mu et al. 2016"],"Citation Start End":[[2203,2217]]} {"Identifier":"2017ApJ...840..118L__Mu_et_al._2016_Instance_4","Paragraph":"Our formula can be used to confront the curvature effect with observations and estimate the decay timescale of the steep decay phase. In observations, the steep decay phase has been observed in the decay phase of the prompt emission phase and flares in GRBs. Since the value of E0 (\n\n\n\n\n∼\n0.3\n–\n1\n\nMeV\n\n\n) in the prompt emission phase is significantly larger than \n\n\n\n\n10\n\nkeV\n\n\n, the β in the steep decay phase of prompt emission would be a linear function of observer time based on Equation (38). This behavior has been observed in a number of bursts, such as GRBs 050814 (Zhang et al. 2009, please see the spectral evolution in the \n\n\n\n\nβ\n−\n\n\nt\n\n\nobs\n\n\n\n\n space), 051001 etc. The linear relation between β and \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n is also found in the steep decay of flares (e.g., Mu et al. 2016). For a linear function β of \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n, one can obtain the slope of the linear function, which is equal to \n\n\n\n\n7.9\n\n\nκ\n\n\nˆ\n\n\n\n\/\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n2.37\n\nkeV\n\n\/\n\n[\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n]\n\n\n based on Equations (38) or (39). Then, the decay timescale \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n of our studying phase can be estimated if the value of \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n is known. We fit the spectral evolution in the decay phase of a flare (\n\n\n\n\n∼\n172\n\ns\n\n\n) in GRB 060904B (Mu et al. 2016) with a linear function. The fitting result, i.e., \n\n\n\n\nβ\n=\n0.84\n+\n0.020\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n with \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n\n\nt\n\n\nobs\n\n\n−\n\n\nt\n\n\np\n\n\n\n\n, is shown in the left panel of Figure 4 with a red solid line. Then, we have \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n119\n\nkeV\n\ns\n\n\n, which is around that found in Mu et al. (2016), i.e., \n\n\n\n\n2.54\n\nkeV\n×\n65.39\n\ns\n\n\n. For a flare (\n\n\n\n\n∼\n116\n\ns\n\n\n) in GRB 131030A, the spectrum at the beginning of the steep decay phase can be fitted with a Band function. With the fitting result found in Mu et al. (2016), i.e., \n\n\n\n\n\n\nα\n\n\nˆ\n\n\n=\n−\n0.91\n\n\n, \n\n\n\n\n\n\nβ\n\n\nˆ\n\n\n=\n−\n3.19\n\n\n, and \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n=\n1.95\n\n\n, we plot the evolution of β based on Equation (38) in the right panel of Figure 4 with a red solid line. Here, we adopt \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n54\n\ns\n\n\n (Mu et al. 2016), which can also be roughly estimated based on the flux evolution. It can be found that Equation (38) describes the spectral evolution approximately, which may reveal that a more appropriate value of parameters (e.g., \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n) may be required for this source. The agreement of our analytical formula and observational data shows that the assumption (2) given at the beginning of Section 2 (i.e., the jet shell has no θ-dependent spectral parameters or Lorentz factor) is applicable in reality.","Citation Text":["Mu et al. (2016)"],"Citation Start End":[[1913,1929]]} {"Identifier":"2017ApJ...840..118L__Mu_et_al._2016_Instance_3","Paragraph":"Our formula can be used to confront the curvature effect with observations and estimate the decay timescale of the steep decay phase. In observations, the steep decay phase has been observed in the decay phase of the prompt emission phase and flares in GRBs. Since the value of E0 (\n\n\n\n\n∼\n0.3\n–\n1\n\nMeV\n\n\n) in the prompt emission phase is significantly larger than \n\n\n\n\n10\n\nkeV\n\n\n, the β in the steep decay phase of prompt emission would be a linear function of observer time based on Equation (38). This behavior has been observed in a number of bursts, such as GRBs 050814 (Zhang et al. 2009, please see the spectral evolution in the \n\n\n\n\nβ\n−\n\n\nt\n\n\nobs\n\n\n\n\n space), 051001 etc. The linear relation between β and \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n is also found in the steep decay of flares (e.g., Mu et al. 2016). For a linear function β of \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n, one can obtain the slope of the linear function, which is equal to \n\n\n\n\n7.9\n\n\nκ\n\n\nˆ\n\n\n\n\/\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n2.37\n\nkeV\n\n\/\n\n[\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n]\n\n\n based on Equations (38) or (39). Then, the decay timescale \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n of our studying phase can be estimated if the value of \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n is known. We fit the spectral evolution in the decay phase of a flare (\n\n\n\n\n∼\n172\n\ns\n\n\n) in GRB 060904B (Mu et al. 2016) with a linear function. The fitting result, i.e., \n\n\n\n\nβ\n=\n0.84\n+\n0.020\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n with \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n\n\nt\n\n\nobs\n\n\n−\n\n\nt\n\n\np\n\n\n\n\n, is shown in the left panel of Figure 4 with a red solid line. Then, we have \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n119\n\nkeV\n\ns\n\n\n, which is around that found in Mu et al. (2016), i.e., \n\n\n\n\n2.54\n\nkeV\n×\n65.39\n\ns\n\n\n. For a flare (\n\n\n\n\n∼\n116\n\ns\n\n\n) in GRB 131030A, the spectrum at the beginning of the steep decay phase can be fitted with a Band function. With the fitting result found in Mu et al. (2016), i.e., \n\n\n\n\n\n\nα\n\n\nˆ\n\n\n=\n−\n0.91\n\n\n, \n\n\n\n\n\n\nβ\n\n\nˆ\n\n\n=\n−\n3.19\n\n\n, and \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n=\n1.95\n\n\n, we plot the evolution of β based on Equation (38) in the right panel of Figure 4 with a red solid line. Here, we adopt \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n54\n\ns\n\n\n (Mu et al. 2016), which can also be roughly estimated based on the flux evolution. It can be found that Equation (38) describes the spectral evolution approximately, which may reveal that a more appropriate value of parameters (e.g., \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n) may be required for this source. The agreement of our analytical formula and observational data shows that the assumption (2) given at the beginning of Section 2 (i.e., the jet shell has no θ-dependent spectral parameters or Lorentz factor) is applicable in reality.","Citation Text":["Mu et al. (2016)"],"Citation Start End":[[1688,1704]]} {"Identifier":"2017ApJ...840..118L__Mu_et_al._2016_Instance_2","Paragraph":"Our formula can be used to confront the curvature effect with observations and estimate the decay timescale of the steep decay phase. In observations, the steep decay phase has been observed in the decay phase of the prompt emission phase and flares in GRBs. Since the value of E0 (\n\n\n\n\n∼\n0.3\n–\n1\n\nMeV\n\n\n) in the prompt emission phase is significantly larger than \n\n\n\n\n10\n\nkeV\n\n\n, the β in the steep decay phase of prompt emission would be a linear function of observer time based on Equation (38). This behavior has been observed in a number of bursts, such as GRBs 050814 (Zhang et al. 2009, please see the spectral evolution in the \n\n\n\n\nβ\n−\n\n\nt\n\n\nobs\n\n\n\n\n space), 051001 etc. The linear relation between β and \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n is also found in the steep decay of flares (e.g., Mu et al. 2016). For a linear function β of \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n, one can obtain the slope of the linear function, which is equal to \n\n\n\n\n7.9\n\n\nκ\n\n\nˆ\n\n\n\n\/\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n2.37\n\nkeV\n\n\/\n\n[\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n]\n\n\n based on Equations (38) or (39). Then, the decay timescale \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n of our studying phase can be estimated if the value of \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n is known. We fit the spectral evolution in the decay phase of a flare (\n\n\n\n\n∼\n172\n\ns\n\n\n) in GRB 060904B (Mu et al. 2016) with a linear function. The fitting result, i.e., \n\n\n\n\nβ\n=\n0.84\n+\n0.020\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n with \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n\n\nt\n\n\nobs\n\n\n−\n\n\nt\n\n\np\n\n\n\n\n, is shown in the left panel of Figure 4 with a red solid line. Then, we have \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n119\n\nkeV\n\ns\n\n\n, which is around that found in Mu et al. (2016), i.e., \n\n\n\n\n2.54\n\nkeV\n×\n65.39\n\ns\n\n\n. For a flare (\n\n\n\n\n∼\n116\n\ns\n\n\n) in GRB 131030A, the spectrum at the beginning of the steep decay phase can be fitted with a Band function. With the fitting result found in Mu et al. (2016), i.e., \n\n\n\n\n\n\nα\n\n\nˆ\n\n\n=\n−\n0.91\n\n\n, \n\n\n\n\n\n\nβ\n\n\nˆ\n\n\n=\n−\n3.19\n\n\n, and \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n=\n1.95\n\n\n, we plot the evolution of β based on Equation (38) in the right panel of Figure 4 with a red solid line. Here, we adopt \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n54\n\ns\n\n\n (Mu et al. 2016), which can also be roughly estimated based on the flux evolution. It can be found that Equation (38) describes the spectral evolution approximately, which may reveal that a more appropriate value of parameters (e.g., \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n) may be required for this source. The agreement of our analytical formula and observational data shows that the assumption (2) given at the beginning of Section 2 (i.e., the jet shell has no θ-dependent spectral parameters or Lorentz factor) is applicable in reality.","Citation Text":["Mu et al. 2016"],"Citation Start End":[[1335,1349]]} {"Identifier":"2017ApJ...840..118L__Mu_et_al._2016_Instance_1","Paragraph":"Our formula can be used to confront the curvature effect with observations and estimate the decay timescale of the steep decay phase. In observations, the steep decay phase has been observed in the decay phase of the prompt emission phase and flares in GRBs. Since the value of E0 (\n\n\n\n\n∼\n0.3\n–\n1\n\nMeV\n\n\n) in the prompt emission phase is significantly larger than \n\n\n\n\n10\n\nkeV\n\n\n, the β in the steep decay phase of prompt emission would be a linear function of observer time based on Equation (38). This behavior has been observed in a number of bursts, such as GRBs 050814 (Zhang et al. 2009, please see the spectral evolution in the \n\n\n\n\nβ\n−\n\n\nt\n\n\nobs\n\n\n\n\n space), 051001 etc. The linear relation between β and \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n is also found in the steep decay of flares (e.g., Mu et al. 2016). For a linear function β of \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n, one can obtain the slope of the linear function, which is equal to \n\n\n\n\n7.9\n\n\nκ\n\n\nˆ\n\n\n\n\/\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n2.37\n\nkeV\n\n\/\n\n[\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n]\n\n\n based on Equations (38) or (39). Then, the decay timescale \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n of our studying phase can be estimated if the value of \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n is known. We fit the spectral evolution in the decay phase of a flare (\n\n\n\n\n∼\n172\n\ns\n\n\n) in GRB 060904B (Mu et al. 2016) with a linear function. The fitting result, i.e., \n\n\n\n\nβ\n=\n0.84\n+\n0.020\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n\n\n with \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n\n\nt\n\n\nobs\n\n\n−\n\n\nt\n\n\np\n\n\n\n\n, is shown in the left panel of Figure 4 with a red solid line. Then, we have \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n119\n\nkeV\n\ns\n\n\n, which is around that found in Mu et al. (2016), i.e., \n\n\n\n\n2.54\n\nkeV\n×\n65.39\n\ns\n\n\n. For a flare (\n\n\n\n\n∼\n116\n\ns\n\n\n) in GRB 131030A, the spectrum at the beginning of the steep decay phase can be fitted with a Band function. With the fitting result found in Mu et al. (2016), i.e., \n\n\n\n\n\n\nα\n\n\nˆ\n\n\n=\n−\n0.91\n\n\n, \n\n\n\n\n\n\nβ\n\n\nˆ\n\n\n=\n−\n3.19\n\n\n, and \n\n\n\n\n\n\nE\n\n\n0\n\n\n(\n\n\n\n\nt\n\n\n\n\n\n\n\nobs\n\n\n=\n0\n)\n=\n1.95\n\n\n, we plot the evolution of β based on Equation (38) in the right panel of Figure 4 with a red solid line. Here, we adopt \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n=\n54\n\ns\n\n\n (Mu et al. 2016), which can also be roughly estimated based on the flux evolution. It can be found that Equation (38) describes the spectral evolution approximately, which may reveal that a more appropriate value of parameters (e.g., \n\n\n\n\n\n\n\n\nt\n\n\n\n\n\n\n\nc\n\n\n\n\n) may be required for this source. The agreement of our analytical formula and observational data shows that the assumption (2) given at the beginning of Section 2 (i.e., the jet shell has no θ-dependent spectral parameters or Lorentz factor) is applicable in reality.","Citation Text":["Mu et al. 2016"],"Citation Start End":[[790,804]]} {"Identifier":"2018MNRAS.479.3438G__Dabringhausen,_Hilker_&_Kroupa_2008_Instance_1","Paragraph":"In the single cloud simulations presented in Paper I and Paper II, the system was treated in isolation, i.e. with no external forces acting upon it. In reality, such a binary would be placed deep in the potential well of a galaxy, where stars and dark matter exert their gravitational influence. To mimic the presence of the galactic spheroid, we include an external potential with a Hernquist profile (Hernquist 1990), which can be written as\n(1)\r\n\\begin{eqnarray*}\r\n\\rho (r) = \\frac{M_*}{2\\pi}\\frac{a_*}{r}\\frac{1}{(r+a_*)^3},\r\n\\end{eqnarray*}\r\nand an enclosed mass given by\n(2)\r\n\\begin{eqnarray*}\r\nm(r) = M_*\\frac{r^2}{(r+a_*)^2},\r\n\\end{eqnarray*}\r\nwhere M* and a* are scaling constants that represent the total mass of the spheroid and the size of core, respectively. Based on a typical MBH–Mbulge relation (Magorrian et al. 1998) and a radius-to-stellar-mass relation (Dabringhausen, Hilker & Kroupa 2008), we choose MH = 4.78 × 102M0 and rH = 3.24 × 102a0, thus implying\n(3)\r\n\\begin{eqnarray*}\r\nm(a_0) \\approx 5\\times 10^{-3} M_0.\r\n\\end{eqnarray*}\r\nAs a consequence, this external force represents only a small perturbation to the dynamics of the interaction that is still dominated by the binary’s gravitational potential. Moreover, because this external potential is spherically symmetric, orbits experience precession only, where energy and angular momentum are conserved. In principle, this precession could enhance stream collisions, prompting more gas onto the binary, although the time-scales are too long with respect to the frequency of cloud infall, which is the dominant effect in our models. Based on this, we do not expect the oscillations induced by this potential to have a secular effect in the overall evolution of the system during the stages modelled. In practice, this potential maintains the binary close to the centre of the reference frame by applying a restoring force when it drifts away due to the interaction with the incoming material. It is important to mention that the gas also feels this external force.","Citation Text":["Dabringhausen, Hilker & Kroupa 2008"],"Citation Start End":[[874,909]]} {"Identifier":"2018AandA...614A..76J__Vollmann_&_Eversberg_(2006)_Instance_1","Paragraph":"For the new observations described in Sect. 3, the spectra are renormalised by applying a linear fit to two wavelength regions, 6455–6559 Å and 6567–6580 Å, on either side of the Hα line. The value for pEW (Hα) is measured over the wavelength range 6560–6565 Å. The selected wavelength range is sufficiently narrow to exclude nearby spectral lines and sufficiently broad to measure the Hα line of a fast rotating star. The value of pEW(Hα) is calculated from\n\n(1)\n\n${\\rm{pEW}(H\\alpha)} = \\int^{\\lambda_2}_{\\lambda_1}\n\\left(1-\\frac{F(\\lambda)}{F_{\\rm{pc}}}\\right){\\rm{d}}\\lambda,$pEW(Hα)= ∫ λ1λ2 1-F(λ)Fpc dλ, \n\n\nwhere Fpc is the average of the median flux in the pseudo-continuum in the ranges [6545:6559] and [6567:6580], λ1 = 6560Å, λ2 = 6565Å, and the error is determined with the method of Vollmann & Eversberg (2006), which is applied as follows:\n\n(2)\n\n$\\sigma_{\\rm{pEW}} = \\frac{\\mathrm\\Delta \\lambda -\n\\rm{pEW(H\\alpha)}}{\\rm{S\/N}} \\sqrt{1 + \\frac{F_{\\rm{pc}}}{F_{1,2}}},$σpEW=Δλ-pEW(Hα)S∕N1+ Fpc F1,2, \n\nwhere Δλ = λ2 − λ1 and F1,2 is the mean flux in the wavelength range between λ1 and λ2. For Hα active stars, i.e. where pEW(Hα) is negative, the normalised Hα luminosity can be expressed as\n\n(3)\n\n$\\log \\left(\\frac{L_{{\\rm{H}}\\alpha}}{L_{\\rm{bol}}}\\right) = \\log \\chi\n+ \\log (-{\\rm{pEW}}({\\rm{H}}\\alpha)),$logLHαLbol = logχ+ log(-pEW(Hα)), \n\nwhere log χ is given as a function of the effective temperature (e.g. Reiners & Basri 2008). Lines with Hα in absorption have positive pEW(Hα) values and lines with Hα in emission have negative pEW(Hα) values. The minimum level of emission in Hα that we are sensitive to is pEW(Hα) ≤−0.5Å, which is the definition for an active star in this work and is indicated by the term Hα active. This detection threshold was determined by visually inspecting the spectra and is consistent with values obtained by Newton et al. (2017) and West et al. (2015). The values derived from the new observations are tabulated in Table A.2.","Citation Text":["Vollmann & Eversberg (2006)"],"Citation Start End":[[796,823]]} {"Identifier":"2020MNRAS.499..462S__Navarro,_Frenk_&_White_1996_Instance_1","Paragraph":"In this work, we consider four different galaxy models from Smirnov & Sotnikova (2018). Full details of the simulations can be found in that work and we refer an interested reader to it. Here, we briefly describe some important aspects of the simulations. Initially, each model consists of an axisymmetric exponential disc:\n(11)$$\\begin{eqnarray}\r\n\\rho (R,z) = \\frac{M_\\mathrm{d}}{4\\pi R_\\mathrm{d}^2 z_\\mathrm{d}} \\exp \\left(-\\frac{R}{R_\\mathrm{d}}\\right) \\operatorname{sech}^2\\left(\\frac{z}{z_\\mathrm{d}}\\right) \\, ,\r\n\\end{eqnarray}$$where Md is the total mass of the disc, Rd is the disc scale length, and zd is the disc scale height, plus spherically symmetric dark halo of NFW-type (Navarro, Frenk & White 1996). The halo is characterized by the ratio Mh(r 4Rd)\/Md, where Mh(r 4Rd) is the dark halo mass inside the sphere with a radius of 4Rd. One model also includes a Hernquist type bulge (Hernquist 1990):\n(12)$$\\begin{eqnarray}\r\n\\rho _\\mathrm{b}(r) = \\frac{M_\\mathrm{b}\\, r_\\mathrm{b}}{2\\pi \\, r\\, (r_\\mathrm{b} + r)^3} \\, ,\r\n\\end{eqnarray}$$where rb is the scale parameter and Mb is the total bulge mass. Disc and halo components are represented by several millions of particles (see Table 1). Bulge particle number is chosen such that the mass of one particle from the bulge is equal to the mass of one particle from the disc. Some important physical parameters of the models are specified in Table 1. The initial equilibrium state of each multicomponent model was prepared via script mkgalaxy (McMillan & Dehnen 2007) from the toolbox for N-body simulation NEMO (Teuben 1995). Evolution of the models was followed for about 8 Gyr using the fastest N-body code for one CPU gyrfalcON (Dehnen 2002). Each model gives rise to a bar after 1−2 Gyr from the beginning of the simulation. Each bar gradually thickens in the vertical direction (clear buckling events can occur depending on the model) and takes a B\/PS shape if seen side-on. Fig. 1 shows the end-state of the bulgeless model with μ = 1.5 and Q(2Rd) = 1.2. This model is our fiducial or ‘main’ model. On the example of this model, we consider below how various projection effects affect the extracted parameters of the B\/PS bulge. For each of the models, we prepared a set of Flexible Image Transport System (FITS) images obtained from the corresponding density distribution of disc\/bulge particles. Such images can then be decomposed using a usual decomposition procedure analogous to that used for images of real galaxies.","Citation Text":["Navarro, Frenk & White 1996"],"Citation Start End":[[688,715]]} {"Identifier":"2015ApJ...801...53C__Straniero_2003_Instance_1","Paragraph":"The poor theoretical knowledge of the stellar mass loss history represents one of the main uncertainties in the computation of AGB stellar models. Low- and intermediate-mass stars lose the majority of their mass during the red giant branch (RGB) and the AGB phases. In 1D stellar evolutionary codes, the mass-loss rate during the RGB phase is commonly parameterized according to the formulation proposed by Reimers (1975):\n2\n\n\n\n\n\nwhere \n\n\n\n\n\n is in units of M\n\n\n\n\n\n\n yr−1 and other quantities are in solar units. The uncertainty affecting this formula was originally quoted by Reimers to be at least a factor of two either way. Later, Fusi-Pecci Renzini (1976) introduced a normalization constant in order to reproduce the horizontal branch morphology of globular clusters (\n\n\n\n\n\n = 0.4).10\n\n10\nFRUITY models adopt this value.\n Depending on the mass lost during the RGB phase (and thus on the value of \n\n\n\n\n\n), stars attain the AGB phase with different envelope masses. Thus, in principle, the RGB mass loss could have an effect on the subsequent AGB nucleosynthesis. Those effects are expected to be important for low-mass stars (M \n\n\n\n\n\n 1.5 M\n\n\n\n\n\n\n) because they spend more time in the RGB phase than do larger masses. Moreover, their envelopes are thinner than in more massive stars, so even a small amount of material lost (e.g., 0.1 M\n\n\n\n\n\n\n) can produce sizeable effects on the occurrence of TDU in the subsequent AGB phase (see, e.g., Straniero 2003). To properly determine the effects of RGB mass-loss rate on AGB nucleosynthesis (and thus on the solar s-only distribution), we calculate a set of M = 1.3 M\n\n\n\n\n\n\n models at different metallicities with \n\n\n\n\n\n. In Figure 10 we report the variations of the surface abundances (\n\n\n\n\n\n) with respect to the corresponding FRUITY cases. We find that \n\n\n\n\n\n are larger at low metallicities (in particular for the heaviest s-only isotopes). This is because at large metallicities this mass experiences a few TDU episodes, even using a milder RGB mass-loss rate. Thus, the final surface s-process enhancement is, in any case, low. By comparison, we also report data relative to a M = 2 \n\n\n\n\n\n Z = 10−2 ([Fe\/H] = −0.15) model. The low variations found in this case confirm that for massive-enough AGB stars a reduced mass-loss rate during the RGB phase has practically no effect. In Figure 11 we report a GCE model computed with \n\n\n\n\n\n in stars with M \n\n\n\n\n\nM\n\n\n\n\n\n\n (hereinafter the Reimers case). We find minor variations in the s-only distribution (see also Table 1), with slightly larger enhancements for the heaviest s-only isotopes (\n\n\n\n\n\n). Our results reinforce the evidence that the major contributors to the solar system s-process inventory are AGB stars in the mass range (1.5–3.0) \n\n\n\n\n\n, as already inferred in Section 3. Their nucleosynthesis is strongly affected by the rate at which they lose mass during the AGB. A viable method to estimate AGB mass loss is based on the observed correlation with the pulsation period (Vassiliadis Wood 1993). Because the evolution of the pulsation period depends on the variations of radius, luminosity, and mass, this relation provides a simple method to estimate the evolution of the mass-loss rate from basic stellar parameters. In our models, the AGB mass loss is determined according to a procedure similar to the one adopted by Vassiliadis Wood (1993), but revising the mass loss–period and the period–luminosity relations, taking into account more recent infrared observations of solar-metallicity AGB stars (see Straniero et al. 2006 and references therein). It has been demonstrated that AGB mass-loss rates are mildly dependent on the metallicity (Groenewegen et al. 2007; Lagadec et al. 2008), and thus we applied the same period–mass loss relation for all AGB models present in the FRUITY database. Nevertheless, it is worth noting that, when a fixed period is defined, the observational data show quite a large scatter. In a period–mass loss plot, a theoretical curve constructed when reducing by a factor of two the mass-loss rate at a fixed period still lies within the observed spread (see Figure 8.10 of Cristallo 2006). This still holds for a mass-loss rate increased by a factor of two. In order to quantify the effects on the s-only distribution induced by a variation of the AGB mass-loss rate, we compute some AGB models with a milder and stronger period–mass loss relations. In Figure 12 we show the results on the final surface distributions of 2 M\n\n\n\n\n\n\n stellar models at various metallicities. In the plot, \n\n\n\n\n\n represents the difference between models computed with the standard \n\n\n\n\n\n–period relation (Straniero et al. 2006) and the modified ones. Obviously, positive differences are obtained with a milder mass-loss rate, while negative differences with the stronger one. Heavy-element surface variations are below 0.1 dex (25%) for the whole s-process distribution, being slightly larger at low metallicity. Thus, we expect that a modified \n\n\n\n\n\n–period relation in the AGB phase will produce an almost rigid shift (upward or downward, depending on the adopted mass-loss law) of the s-process isotopes. In order to verify this statement, we compute a GCE model with a milder \n\n\n\n\n\n–period relation during the AGB phase (hereinafter the Mloss AGB case). The results are shown in Figure 13; the corresponding data are reported in Table 1. As expected, for s-only isotopes with A ≥ 96, there is an almost rigid upper shift of solar percentages (∼25%). In summary, a rigid shift (upward or downward) of the s-process isotopic inventory can be obtained by adopting a different prescription for the AGB mass-loss rate within the intrinsic observed scatter in the \n\n\n\n\n\n–period relation.","Citation Text":["Straniero 2003"],"Citation Start End":[[1445,1459]]} {"Identifier":"2019AandA...622A..60C__Torrealba_et_al._2015_Instance_1","Paragraph":"In order to establish the completeness and purity of the RR Lyrae stars confirmed by the SOS Cep&RRL pipeline and to estimate the number of new discoveries by Gaia, we performed a deep and careful comparison with the literature. As a first step, the catalogue of 140 784 confirmed sources was cross-matched against all major catalogues of known RR Lyrae stars that are available. We primarily used the OGLE catalogues for RR Lyrae stars (version IV of the survey, Soszyński et al. 2014, 2016), but we also used RR Lyrae stars by CTRS (Drake et al. 2013a,b, 2014, 2017; Torrealba et al. 2015), ASAS (Pojmanski 1997; Richards et al. 2012), ASAS-SN (Jayasinghe et al. 2018), ATLAS (Tonry et al. 2018), IOMC (Alfonso-Garzón et al. 2012), LINEAR (Palaversa et al. 2013), NSVS (Kinemuchi et al. 2006), Pann-Stars (PS1 Sesar et al. 2017), and from the works based on Kepler\/K2 (Debosscher et al. 2011; Nemec et al. 2011; Molnár et al. 2015a,b, 2016) and on the Simbad database (Wenger et al. 2000). These cross-matches returned a list of 88 578 known RR Lyrae stars in our sample of 140 784 stars. The SOS Cep&RRL confirmed RR Lyrae stars were also cross-matched against catalogues of candidate RR Lyrae stars discovered by the VVV survey (Gran et al. 2016; Minniti et al. 2017; D. Minniti, priv. comm.) in the MW disc and bulge. This returned 319 VVV cross-identified sources in the MW disc and 222 in the MW bulge. We thus confirm these VVV candidates. For known RR Lyrae stars in GCs, the main reference was the catalogue of Clement et al. (2001), which was updated to the latest literature as described in Garofalo et al. (in prep.). For variables in dSphs, we used the following references: Kaluzny et al. (1995), Clementini et al. (2005), Kinemuchi et al. (2008), Dall’Ora et al. (2012) and Garofalo et al. (2013). These latter cross-matches returned a list of 1986 further known RR Lyrae stars. At the end of this cross-match procedure, of the 140 784 RR Lyrae stars that are confirmed by the SOS Cep&RRL pipeline, 90 564 were shown to be known previously, and 50 220 are new discoveries by Gaia.","Citation Text":["Torrealba et al. 2015"],"Citation Start End":[[569,590]]} {"Identifier":"2019AandA...622A..6Minniti_et_al._2017_Instance_1","Paragraph":"In order to establish the completeness and purity of the RR Lyrae stars confirmed by the SOS Cep&RRL pipeline and to estimate the number of new discoveries by Gaia, we performed a deep and careful comparison with the literature. As a first step, the catalogue of 140 784 confirmed sources was cross-matched against all major catalogues of known RR Lyrae stars that are available. We primarily used the OGLE catalogues for RR Lyrae stars (version IV of the survey, Soszyński et al. 2014, 2016), but we also used RR Lyrae stars by CTRS (Drake et al. 2013a,b, 2014, 2017; Torrealba et al. 2015), ASAS (Pojmanski 1997; Richards et al. 2012), ASAS-SN (Jayasinghe et al. 2018), ATLAS (Tonry et al. 2018), IOMC (Alfonso-Garzón et al. 2012), LINEAR (Palaversa et al. 2013), NSVS (Kinemuchi et al. 2006), Pann-Stars (PS1 Sesar et al. 2017), and from the works based on Kepler\/K2 (Debosscher et al. 2011; Nemec et al. 2011; Molnár et al. 2015a,b, 2016) and on the Simbad database (Wenger et al. 2000). These cross-matches returned a list of 88 578 known RR Lyrae stars in our sample of 140 784 stars. The SOS Cep&RRL confirmed RR Lyrae stars were also cross-matched against catalogues of candidate RR Lyrae stars discovered by the VVV survey (Gran et al. 2016; Minniti et al. 2017; D. Minniti, priv. comm.) in the MW disc and bulge. This returned 319 VVV cross-identified sources in the MW disc and 222 in the MW bulge. We thus confirm these VVV candidates. For known RR Lyrae stars in GCs, the main reference was the catalogue of Clement et al. (2001), which was updated to the latest literature as described in Garofalo et al. (in prep.). For variables in dSphs, we used the following references: Kaluzny et al. (1995), Clementini et al. (2005), Kinemuchi et al. (2008), Dall’Ora et al. (2012) and Garofalo et al. (2013). These latter cross-matches returned a list of 1986 further known RR Lyrae stars. At the end of this cross-match procedure, of the 140 784 RR Lyrae stars that are confirmed by the SOS Cep&RRL pipeline, 90 564 were shown to be known previously, and 50 220 are new discoveries by Gaia.","Citation Text":["Minniti et al. 2017"],"Citation Start End":[[1251,1270]]} {"Identifier":"2019ApJ...887...24T__Netzer_2009_Instance_1","Paragraph":"In Figure 7, we find a trend between \n\n\n\n\n\n and SFR over about 3 orders of magnitude in far-IR luminosity\/SFR. The solid line shows the best-fit (a logarithmic linear least-squares bisector fit) correlation for the whole sample of QSOs, with a power law of \n\n\n\n\n\n. The Spearman rank correlation coefficient for this correlation is 0.77 with a high significance (P 10−5) but substantial scatter. Our result is in general agreement with the correlation found between AGN activity and star formation, i.e., \n\n\n\n\n\n (α ∼ 1.1–1.7; see Netzer 2009; Chen et al. 2013; Hickox et al. 2014; Duras et al. 2017; Dai et al. 2018; Izumi et al. 2019 and references therein). As noted in previous works (see e.g., Dai et al. 2018), the variation of slope might be attributed to different sample compositions and\/or methods of analysis. However, all of these studies, including our own, reveal a significant trend between the SFR and BH accretion spanning a wide range of luminosity, implying that there may be a direct connection between the AGN and star formation activities over galaxy evolution timescales. In addition, there is evidence that SMBHs have grown in step with their host galaxies since z ∼ 2 (Daddi et al. 2007; Mullaney et al. 2012). The median value of \n\n\n\n\n\n\/SFR is 6.0 × 10−3 for IR QSOs, consistent with the value derived in Xia et al. (2012). In contrast, the \n\n\n\n\n\n\/SFR values for high-z QSOs are found to be about a factor of 10 higher (a median of 7.3 × 10−2) than the local IR QSOs. This is consistent with the “overmassive” BH revealed for z > 5 QSOs (Walter et al. 2004; Wang et al. 2010, 2013, 2016), for which a plausible interpretation is likely related to the different efficiency of gas accretion to the central SMBHs, i.e., faster gas consumption in the most massive SMBHs. Similar results have been reported by Hao et al. (2008), who found a trend that the SFR increases with the accretion rate for both low- and high-redshift IR-luminous QSOs, and the relative growth of BHs and their host spheroids may depend on the intensity of QSO activities.","Citation Text":["Netzer 2009"],"Citation Start End":[[530,541]]} {"Identifier":"2022ApJ...929....1H__Pacucci_et_al._2022_Instance_1","Paragraph":"There are several possible physical processes to reconcile these discrepancies between the models and the observations at z ∼ 10–13. As discussed in Harikane et al. (2021b), less efficient mass quenching and\/or lower dust obscuration than assumed in the models can explain the existence of these UV-bright galaxies. Active galactic nucleus (AGN) activity may also boost the UV luminosity in these galaxies. Previous studies indicate that the AGN fraction starts to increase at M\nUV ≃ −22 mag (Ono et al. 2018; Stevans et al. 2018; Adams et al. 2020; Harikane et al. 2022; see also Piana et al. 2022). If we assume that the UV luminosities of HD1 and HD2 are solely powered by black holes, the inferred black hole masses are ∼108\nM\n⊙, assuming accretion at the Eddington rate (Pacucci et al. 2022), in accordance with expectations for high-redshift quasars (see, e.g., Haiman & Menou 2000 and Willott et al. 2010). In addition, note that a ∼108\nM\n⊙ black hole at z ∼ 12 could be the progenitor of z ∼ 7 quasars, as the growth time to reach a mass of 109–1010\nM\n⊙, typical of z > 6 quasars detected thus far, is shorter than the cosmic time between z = 12–13 and z = 7, for an Eddington-limited accretion. It is also possible that the observed bright sources at z ∼ 10–13 are galaxies in a short-time starburst phase that is not captured in the models whose outputs are averaged over a time interval (see also Dayal et al. 2013). Finally, a top-heavier IMF would explain the discrepancies by producing more UV photons at the same stellar mass. It is possible that these bright galaxies (especially HD1 and HD2) are merging systems that are not resolved in the ground-based images. However, even if they are major mergers, the UV luminosity will decrease only by a factor of a few, which would not explain the discrepancy at z ∼ 13 (see also discussions in Harikane et al. 2022; Shibuya et al. 2022). In any case, if these bright z ∼ 10–13 galaxies are spectroscopically confirmed, the discrepancies will motivate the exploration of new physical processes that are responsible for driving the formation of these bright galaxies in the early universe.","Citation Text":["Pacucci et al. 2022"],"Citation Start End":[[776,795]]} {"Identifier":"2018ApJ...860...59K__Stupar_et_al._2008_Instance_1","Paragraph":"For the distance to the source of HESS J1825−137 of 4 kpc (based on dispersion measure using the models for Galactic electrons by Taylor & Cordes 1993; Cordes & Lazio 2002), the measured angular size of the latter corresponds to the 70 pc linear size of the gamma-ray production region. Although the gamma-ray image deviates from the spherically symmetric shape; below for simplicity we will assume that the radius of the source is 35 pc. The detection of a Hα rim at a distance of \n\n\n\n\n\n from the pulsar PSR J1826-1334 has been interpreted as a signature of the progenitor SNR (see Stupar et al. 2008; Voisin et al. 2016). As illustrated in Figure 4, in the case of an ISM density gradient, the measured radius does not coincide with the radius, Rsnr . If the pulsar is still located inside the SNR then the SNR radius cannot be significantly smaller than the observed distance: \n\n\n\n\n\n. Thus, with a factor of two uncertainty one can estimate the radius based on Sedov’s solution:\n40\n\n\n\n\n\nwhere \n\n\n\n\n\n are the density, the hydrogen number density, and the proton mass, respectively. Thus, the SNR shell can be located at the distance of \n\n\n\n\n\n pc, provided that the following condition is fulfilled:\n41\n\n\n\n\n\nwhere the numerical value corresponds to \n\n\n\n\n\n. The ejecta energy at SN type II is constrained by \n\n\n\n\n\n, while the age of the source is limited by \n\n\n\n\n\n (for \n\n\n\n\n\n). Thus, Sedov’s solution is consistent with the observed size of the SNR when \n\n\n\n\n\n. Note that de Jager & Djannati-Ataï (2009) derived a somewhat smaller upper limit for \n\n\n\n\n\n assuming the braking index n = 2. This upper limit seems to be below the typical density of the interstellar gas in the Galactic Plane. Moreover, Voisin et al. (2016) reported the presence of several molecular clouds in the small angular proximity to the nebula with an average number density \n\n\n\n\n\n and characteristic size \n\n\n\n\n\n. It is likely that one of these clouds is responsible for the anisotropic expansion of the nebula, thus it should be located close to the nebula. The gas density in molecular clouds is expected to follow the King’s profile:\n42\n\n\n\n\n\nThus, the density to the south of the pulsar can hardly be as low as it is required by Sedov’s solution. Instead, it should be comparable to the upper limit of \n\n\n\n\n\n obtained by Voisin et al. (2016).","Citation Text":["Stupar et al. 2008"],"Citation Start End":[[583,601]]} {"Identifier":"2020ApJ...902L..42W__Zhang_2019_Instance_1","Paragraph":"In some cases, the precursor emission has a nonthermal spectrum, especially GRB111117510 and GRB160804180 with ΔBIC ≳ 6. These cases may be explained by the NS magnetospheric interaction model (assuming that the sources are nearby). For NS mergers with the surface magnetic field \n\n\n\n\n\n for the primary NS, the typical spectrum may be approximately described by a synchrotron radiation spectrum of a photon index around −2\/3 peaking at ∼MeV, because of the effect of synchrotron-pair cascades (Wang et al. 2018a, 2018b). Such a model can well explain the photon indices and peak energies of the nonthermal precursor bursts, e.g., GRB111117510, GRB140209313, and GRB160804180 (Wang et al. 2018b). The precursor emission time for this magnetospheric interaction model roughly coincides with the gravitational-wave radiation chirp signal time. So the waiting time between the precursor and the main burst should correspond to the time delay between the GW signal and the SGRB signal. This timescale consists of three parts (Zhang 2019): the time (\n\n\n\n\n\n) for the jet to be launched by the central engine, the time (Δtbo) for the jet to propagate through and break out from the circumburst medium, and the time (ΔtGRB) for the jet to reach the energy dissipation radius (e.g., the photospheric radius or the internal shock radius). The last term is \n\n\n\n\n\n, while the first two terms depend on the jet-launch models. According to the Table 1 in Zhang (2019), for most models, \n\n\n\n\n\n = 0.01–1 s. Consequently, one would also expect \n\n\n\n\n\n ∼ \n\n\n\n\n\n. An exception is the SMNS\/SNS magnetic model, in which a uniform-rotation-supported supramassive NS (SMNS) is formed after the NS merger, which subsequently becomes a stable NS (SNS). In this model, the waiting time is dominated by the term \n\n\n\n\n\n, which is mainly contributed by the time needed to clean the environment to launch a relativistic jet (Metzger et al. 2011; Zhang 2019). In this case, one expects \n\n\n\n\n\n ≫ \n\n\n\n\n\n. In our sample, we find most events satisfy \n\n\n\n\n\n ∼ \n\n\n\n\n\n, except GRB191221802, which has \n\n\n\n\n\n\/\n\n\n\n\n\n ≈ 52 and \n\n\n\n\n\n s. We also notice that for GRB090510016, Troja et al. (2010) found two precursors in the Swift data, but only the second precursor can be found in Fermi data (consistent with our results). Its first precursor is found to be of \n\n\n\n\n\n\/\n\n\n\n\n\n ≈ 40 and \n\n\n\n\n\n ≈ 12 s, while its second precursor in our analysis is consistent with the photospheric radiation of the fireball. Therefore, its first precursor with a long waiting time (\n\n\n\n\n\n\/\n\n\n\n\n\n ≫ 1) could originate from NS magnetospheric interaction, and such long waiting times are caused by the jet-launch mechanism in the SMNS\/SNS magnetic model. In conclusion, according to this model, an SNS engine might have been formed after the merger in events with \n\n\n\n\n\n\/\n\n\n\n\n\n ≫ 1, e.g., GRB090510016 and GRB191221802.","Citation Text":["Zhang 2019"],"Citation Start End":[[1021,1031]]} {"Identifier":"2020ApJ...902L..42W__Zhang_2019_Instance_2","Paragraph":"In some cases, the precursor emission has a nonthermal spectrum, especially GRB111117510 and GRB160804180 with ΔBIC ≳ 6. These cases may be explained by the NS magnetospheric interaction model (assuming that the sources are nearby). For NS mergers with the surface magnetic field \n\n\n\n\n\n for the primary NS, the typical spectrum may be approximately described by a synchrotron radiation spectrum of a photon index around −2\/3 peaking at ∼MeV, because of the effect of synchrotron-pair cascades (Wang et al. 2018a, 2018b). Such a model can well explain the photon indices and peak energies of the nonthermal precursor bursts, e.g., GRB111117510, GRB140209313, and GRB160804180 (Wang et al. 2018b). The precursor emission time for this magnetospheric interaction model roughly coincides with the gravitational-wave radiation chirp signal time. So the waiting time between the precursor and the main burst should correspond to the time delay between the GW signal and the SGRB signal. This timescale consists of three parts (Zhang 2019): the time (\n\n\n\n\n\n) for the jet to be launched by the central engine, the time (Δtbo) for the jet to propagate through and break out from the circumburst medium, and the time (ΔtGRB) for the jet to reach the energy dissipation radius (e.g., the photospheric radius or the internal shock radius). The last term is \n\n\n\n\n\n, while the first two terms depend on the jet-launch models. According to the Table 1 in Zhang (2019), for most models, \n\n\n\n\n\n = 0.01–1 s. Consequently, one would also expect \n\n\n\n\n\n ∼ \n\n\n\n\n\n. An exception is the SMNS\/SNS magnetic model, in which a uniform-rotation-supported supramassive NS (SMNS) is formed after the NS merger, which subsequently becomes a stable NS (SNS). In this model, the waiting time is dominated by the term \n\n\n\n\n\n, which is mainly contributed by the time needed to clean the environment to launch a relativistic jet (Metzger et al. 2011; Zhang 2019). In this case, one expects \n\n\n\n\n\n ≫ \n\n\n\n\n\n. In our sample, we find most events satisfy \n\n\n\n\n\n ∼ \n\n\n\n\n\n, except GRB191221802, which has \n\n\n\n\n\n\/\n\n\n\n\n\n ≈ 52 and \n\n\n\n\n\n s. We also notice that for GRB090510016, Troja et al. (2010) found two precursors in the Swift data, but only the second precursor can be found in Fermi data (consistent with our results). Its first precursor is found to be of \n\n\n\n\n\n\/\n\n\n\n\n\n ≈ 40 and \n\n\n\n\n\n ≈ 12 s, while its second precursor in our analysis is consistent with the photospheric radiation of the fireball. Therefore, its first precursor with a long waiting time (\n\n\n\n\n\n\/\n\n\n\n\n\n ≫ 1) could originate from NS magnetospheric interaction, and such long waiting times are caused by the jet-launch mechanism in the SMNS\/SNS magnetic model. In conclusion, according to this model, an SNS engine might have been formed after the merger in events with \n\n\n\n\n\n\/\n\n\n\n\n\n ≫ 1, e.g., GRB090510016 and GRB191221802.","Citation Text":["Zhang (2019)"],"Citation Start End":[[1440,1452]]} {"Identifier":"2020ApJ...902L..42W__Zhang_2019_Instance_3","Paragraph":"In some cases, the precursor emission has a nonthermal spectrum, especially GRB111117510 and GRB160804180 with ΔBIC ≳ 6. These cases may be explained by the NS magnetospheric interaction model (assuming that the sources are nearby). For NS mergers with the surface magnetic field \n\n\n\n\n\n for the primary NS, the typical spectrum may be approximately described by a synchrotron radiation spectrum of a photon index around −2\/3 peaking at ∼MeV, because of the effect of synchrotron-pair cascades (Wang et al. 2018a, 2018b). Such a model can well explain the photon indices and peak energies of the nonthermal precursor bursts, e.g., GRB111117510, GRB140209313, and GRB160804180 (Wang et al. 2018b). The precursor emission time for this magnetospheric interaction model roughly coincides with the gravitational-wave radiation chirp signal time. So the waiting time between the precursor and the main burst should correspond to the time delay between the GW signal and the SGRB signal. This timescale consists of three parts (Zhang 2019): the time (\n\n\n\n\n\n) for the jet to be launched by the central engine, the time (Δtbo) for the jet to propagate through and break out from the circumburst medium, and the time (ΔtGRB) for the jet to reach the energy dissipation radius (e.g., the photospheric radius or the internal shock radius). The last term is \n\n\n\n\n\n, while the first two terms depend on the jet-launch models. According to the Table 1 in Zhang (2019), for most models, \n\n\n\n\n\n = 0.01–1 s. Consequently, one would also expect \n\n\n\n\n\n ∼ \n\n\n\n\n\n. An exception is the SMNS\/SNS magnetic model, in which a uniform-rotation-supported supramassive NS (SMNS) is formed after the NS merger, which subsequently becomes a stable NS (SNS). In this model, the waiting time is dominated by the term \n\n\n\n\n\n, which is mainly contributed by the time needed to clean the environment to launch a relativistic jet (Metzger et al. 2011; Zhang 2019). In this case, one expects \n\n\n\n\n\n ≫ \n\n\n\n\n\n. In our sample, we find most events satisfy \n\n\n\n\n\n ∼ \n\n\n\n\n\n, except GRB191221802, which has \n\n\n\n\n\n\/\n\n\n\n\n\n ≈ 52 and \n\n\n\n\n\n s. We also notice that for GRB090510016, Troja et al. (2010) found two precursors in the Swift data, but only the second precursor can be found in Fermi data (consistent with our results). Its first precursor is found to be of \n\n\n\n\n\n\/\n\n\n\n\n\n ≈ 40 and \n\n\n\n\n\n ≈ 12 s, while its second precursor in our analysis is consistent with the photospheric radiation of the fireball. Therefore, its first precursor with a long waiting time (\n\n\n\n\n\n\/\n\n\n\n\n\n ≫ 1) could originate from NS magnetospheric interaction, and such long waiting times are caused by the jet-launch mechanism in the SMNS\/SNS magnetic model. In conclusion, according to this model, an SNS engine might have been formed after the merger in events with \n\n\n\n\n\n\/\n\n\n\n\n\n ≫ 1, e.g., GRB090510016 and GRB191221802.","Citation Text":["Zhang 2019"],"Citation Start End":[[1914,1924]]} {"Identifier":"2019MNRAS.488.5029H__Sargsyan_et_al._2012_Instance_1","Paragraph":"For the first time, we detected [C ii] 158-μm emission from a GRB host galaxy at z > 2. This is the second detection of [C ii] 158-μm emission among known GRB host galaxies, following GRB 980425 (Michałowski et al. 2016). The [C ii] 158-μm fine structure line is the dominant cooling line of the cool interstellar medium, arising from photodissociation regions (PDR) on molecular cloud surfaces. It is one of the brightest emission lines from star-forming galaxies from FIR to metre wavelengths, almost unaffected by dust extinction. [C ii] 158-μm luminosity, L[C II], has been discussed as an indicator of SFR (e.g. Stacey et al. 2010). If L[C II] scales linearly with SFR, the ratio to FIR luminosity, L[C II]\/LFIR, is expected to be constant, since LFIR is a linear function of SFR (e.g. Kennicutt 1998a). However, LC II\/LFIR is not constant, but declines with increasing LFIR, known as the ‘[C ii] deficit’ (e.g. Luhman et al. 1998, 2003; Malhotra et al. 2001; Sargsyan et al. 2012; Díaz-Santos et al. 2013, 2017; Spilker et al. 2016). The [C ii] deficit persists when including high-z galaxies (e.g. Stacey et al. 2010; Wang et al. 2013; Rawle et al. 2014). In Fig. 5, we compare the [C ii] deficit in the GRB 080207 host and other star-forming galaxies. Two GRB hosts are shown by stars: GRB 080207 (orange star) and 980425 (blue star). The comparison sample is compiled from the literature up to z ∼ 3 (Malhotra et al. 2001; Cormier et al. 2010, 2014; Ivison et al. 2010; Stacey et al. 2010; Sargsyan et al. 2012; Farrah et al. 2013; Magdis et al. 2014; Brisbin et al. 2015; Gullberg et al. 2015; Schaerer et al. 2015). Active galactic nuclei are separated from star-forming galaxies based on either (i) the explicit description in the literature or (ii) EWPAH 6.2μm 0.1 (Sargsyan et al. 2012). As reported by previous studies (e.g. Maiolino et al. 2009; Stacey et al. 2010), high-z galaxies are located at a different place from local galaxies in the L[C II]\/LFIR–LFIR plane.","Citation Text":["Sargsyan et al. 2012"],"Citation Start End":[[965,985]]} {"Identifier":"2019MNRAS.488.5029H__Sargsyan_et_al._2012_Instance_2","Paragraph":"For the first time, we detected [C ii] 158-μm emission from a GRB host galaxy at z > 2. This is the second detection of [C ii] 158-μm emission among known GRB host galaxies, following GRB 980425 (Michałowski et al. 2016). The [C ii] 158-μm fine structure line is the dominant cooling line of the cool interstellar medium, arising from photodissociation regions (PDR) on molecular cloud surfaces. It is one of the brightest emission lines from star-forming galaxies from FIR to metre wavelengths, almost unaffected by dust extinction. [C ii] 158-μm luminosity, L[C II], has been discussed as an indicator of SFR (e.g. Stacey et al. 2010). If L[C II] scales linearly with SFR, the ratio to FIR luminosity, L[C II]\/LFIR, is expected to be constant, since LFIR is a linear function of SFR (e.g. Kennicutt 1998a). However, LC II\/LFIR is not constant, but declines with increasing LFIR, known as the ‘[C ii] deficit’ (e.g. Luhman et al. 1998, 2003; Malhotra et al. 2001; Sargsyan et al. 2012; Díaz-Santos et al. 2013, 2017; Spilker et al. 2016). The [C ii] deficit persists when including high-z galaxies (e.g. Stacey et al. 2010; Wang et al. 2013; Rawle et al. 2014). In Fig. 5, we compare the [C ii] deficit in the GRB 080207 host and other star-forming galaxies. Two GRB hosts are shown by stars: GRB 080207 (orange star) and 980425 (blue star). The comparison sample is compiled from the literature up to z ∼ 3 (Malhotra et al. 2001; Cormier et al. 2010, 2014; Ivison et al. 2010; Stacey et al. 2010; Sargsyan et al. 2012; Farrah et al. 2013; Magdis et al. 2014; Brisbin et al. 2015; Gullberg et al. 2015; Schaerer et al. 2015). Active galactic nuclei are separated from star-forming galaxies based on either (i) the explicit description in the literature or (ii) EWPAH 6.2μm 0.1 (Sargsyan et al. 2012). As reported by previous studies (e.g. Maiolino et al. 2009; Stacey et al. 2010), high-z galaxies are located at a different place from local galaxies in the L[C II]\/LFIR–LFIR plane.","Citation Text":["Sargsyan et al. 2012"],"Citation Start End":[[1499,1519]]} {"Identifier":"2019MNRAS.488.5029H__Sargsyan_et_al._2012_Instance_3","Paragraph":"For the first time, we detected [C ii] 158-μm emission from a GRB host galaxy at z > 2. This is the second detection of [C ii] 158-μm emission among known GRB host galaxies, following GRB 980425 (Michałowski et al. 2016). The [C ii] 158-μm fine structure line is the dominant cooling line of the cool interstellar medium, arising from photodissociation regions (PDR) on molecular cloud surfaces. It is one of the brightest emission lines from star-forming galaxies from FIR to metre wavelengths, almost unaffected by dust extinction. [C ii] 158-μm luminosity, L[C II], has been discussed as an indicator of SFR (e.g. Stacey et al. 2010). If L[C II] scales linearly with SFR, the ratio to FIR luminosity, L[C II]\/LFIR, is expected to be constant, since LFIR is a linear function of SFR (e.g. Kennicutt 1998a). However, LC II\/LFIR is not constant, but declines with increasing LFIR, known as the ‘[C ii] deficit’ (e.g. Luhman et al. 1998, 2003; Malhotra et al. 2001; Sargsyan et al. 2012; Díaz-Santos et al. 2013, 2017; Spilker et al. 2016). The [C ii] deficit persists when including high-z galaxies (e.g. Stacey et al. 2010; Wang et al. 2013; Rawle et al. 2014). In Fig. 5, we compare the [C ii] deficit in the GRB 080207 host and other star-forming galaxies. Two GRB hosts are shown by stars: GRB 080207 (orange star) and 980425 (blue star). The comparison sample is compiled from the literature up to z ∼ 3 (Malhotra et al. 2001; Cormier et al. 2010, 2014; Ivison et al. 2010; Stacey et al. 2010; Sargsyan et al. 2012; Farrah et al. 2013; Magdis et al. 2014; Brisbin et al. 2015; Gullberg et al. 2015; Schaerer et al. 2015). Active galactic nuclei are separated from star-forming galaxies based on either (i) the explicit description in the literature or (ii) EWPAH 6.2μm 0.1 (Sargsyan et al. 2012). As reported by previous studies (e.g. Maiolino et al. 2009; Stacey et al. 2010), high-z galaxies are located at a different place from local galaxies in the L[C II]\/LFIR–LFIR plane.","Citation Text":["Sargsyan et al. 2012"],"Citation Start End":[[1780,1800]]} {"Identifier":"2022MNRAS.517.5744G__Cazaux_et_al._2017_Instance_1","Paragraph":"Jiang et al. (1975) estimated the infrared band strength of CO ice deposited at high pressure compared to modern setups: their deposition rate of 0.5 to 2 μm requires a pressure about 16 to 66 times higher than typical experiments performed at 1 × 10−6 mbar during deposition. To obtain this band strength, Jiang et al. (1975) also adopted a literature value of the CO ice density measured at a relatively high temperature, 30 K (Vegard 1930). According to Luna et al. (2022) and this work, the CO ice density depends on the temperature and pressure during deposition, and therefore, the value of the CO infrared band strength in Jiang et al. (1975) needs a revision. We propose to use $\\mathcal {A}(\\rm CO)$ = (8.7 ± 0.5) × 10−18 cm molecule−1 for future column density estimations. This value is valid in the experimental range from 11 to 28 K deposition temperatures investigated in this work, for which no variations of the integrated absorbance area and sticking probability were found (Cazaux et al. 2017). The CO ice column density values reported in previous experimental and observational papers might thus be underestimated, they would be about 23 per cent lower than the actual value. Most of the CO ice column densities reported in the literature adopted a band strength of $\\mathcal {A}(\\rm CO)$ = 1.1 × 10−17 cm molecule−1 (Jiang et al. 1975), they would need to be multiplied by a factor of 1.3 for correction. An example is the number of monolayers on the surface, or just beneath the surface of the ice, involved in the photodesorption of CO, i.e. N = 5 × 1015 molecules cm−2 or about 5 monolayers (ML) where 1 ML = 1 × 1015 molecules cm−2 (Muñoz Caro et al. 2010; Fayolle et al. 2011; Chen et al. 2014). After correction, this becomes 6.5 ML. Considering our average density value of CO ice deposited at 11 K, 0.837 g cm−3, and equation (24), it is found that the thickness of one monolayer is 0.56 nm, and 3.36 nm for the top 6.5 ML of ice. The UV photons emitted by the MDHL that are absorbed deeper than 3.36 nm would not lead us to photodesorption of CO molecules.","Citation Text":["Cazaux et al. 2017"],"Citation Start End":[[994,1012]]} {"Identifier":"2021AandA...653L..10Z__Leroy_et_al._2008_Instance_1","Paragraph":"SFR and \n\n\n\n\nL\n\nCO(1-0)\n′\n\n\n\n$ L^\\prime_{\\rm CO(1{-}0)} $\n\n\n\n can be derived from observations, but the molecular gas mass, MH2 = αCO × \n\n\n\n\nL\n\nCO(1-0)\n′\n\n\n\n$ L^\\prime_{\\rm CO(1{-}0)} $\n\n\n\n, is the key quantity of interest. The observed SFR\/\n\n\n\n\nL\n\nCO(1-0)\n′\n\n\n\n$ L^\\prime_{\\rm CO(1{-}0)} $\n\n\n\n ratio is related to both the depletion time (τdep) and the CO-to-H2 conversion factor (αCO) as SFR\/\n\n\n\n\nL\n\nCO(1-0)\n′\n\n\n\n$ L^\\prime_{\\rm CO(1{-}0)} $\n\n\n\n = SFR\/(MH2\/αCO) = αCO\/τdep. Many studies have shown that αCO increases rapidly at low metallicity theoretically and observationally (Israel 1997; Glover & Mac Low 2011; Leroy et al. 2011; Narayanan et al. 2012; Elmegreen et al. 2013; Shi et al. 2016). If τdep is constant, as is found for the nearby disc galaxies (Leroy et al. 2008; Bigiel et al. 2011), then the dependence of the SFR\/\n\n\n\n\nL\n\nCO(1-0)\n′\n\n\n\n$ L^\\prime_{\\rm CO(1{-}0)} $\n\n\n\n ratio on metallicity is the direct consequence of the variation of αCO. However, τdep in dwarf galaxies remains uncertain and tends to be shorter at a lower mass and at a higher specific SFR (sSFR; Saintonge et al. 2011; Shi et al. 2014; Hunt et al. 2020). IZw18, as a dwarf galaxy with a relatively high sSFR and low mass, is likely to have low τdep. We speculates that as αCO = τdep × \n\n\n\nSFR\n\n\nL\n\nCO\n(\n1\n−\n0\n)\n\n′\n\n\n\n\n$ \\frac{\\mathrm{SFR}}{L^\\prime_{\\mathrm{CO(1{-}0)}}} $\n\n\n, the high SFR\/\n\n\n\n\nL\n\nCO(1-0)\n′\n\n\n\n$ L^\\prime_{\\rm CO(1{-}0)} $\n\n\n\n ratio of IZw18 would overwhelm the possibly low τdep, and this would result in a high αCO. Moreover, considering the dependence of αCO on both sSFR and metallicity for the metal poor galaxies, IZw18 follows the empirical relation found in Hunt et al. (2020) within the uncertainty of the stellar mass, as shown in the bottom right corner of Fig. 5. This relation was derived based on a recent compilation of ∼400 metal poor galaxies (Ginolfi et al. 2020, MAGMA). We note that the individual star-forming regions of the metal-poor galaxies from Shi et al. (2015, 2016) all fall slightly above the relation, but well within the scatter of the global measurements of the galaxies. This indicates that αCO changes continuously with metallicity and sSFR. A further constraint on the conversion factor (αCO) of IZw18 is beyond the scope of this paper.","Citation Text":["Leroy et al. 2008"],"Citation Start End":[[763,780]]} {"Identifier":"2022MNRAS.515.5523L__Owocki_et_al._2022_Instance_1","Paragraph":"The behaviour of the radio emission from the early-type magnetic stars has been definitively quantified by the empirical scaling relationship between the radio spectral luminosity and the magnetic flux rate: $L_{\\nu ,\\mathrm{rad}} {\\propto } (\\Phi \/ P_{\\mathrm{rot}})^2 = {B_{\\mathrm{p}}^2 R_{\\ast }^{4}} \/ {P_{\\mathrm{rot}}^2}$, found by Leto et al. (2021) and confirmed by Shultz et al. (2022). This empirical relationship is the consequence of the physical mechanism supporting the non-thermal acceleration able to produce the electrons responsible for the magnetospheric radio emission of early-type magnetic stars. It was recently demonstrated by Owocki et al. (2022) that the power provided by centrifugal breakout events, continuously occurring within the stellar magnetosphere, is directly related to the power of the radio emission. From this point of view, the CBOs are non-random events. Breakouts occur continuously in a well-constrained magnetospheric region, where the resulting reconnection of the magnetic fields drives the acceleration of the local electrons. The CBO luminosity is related to the stellar parameters by the relation (Owocki et al. 2022): \n$$\\begin{eqnarray*}\r\nL_{\\mathrm{CBO}} = \\frac{B_{\\mathrm{p}}^2 R_{\\ast }^3}{P_{\\mathrm{rot}}} \\times W {\\mathrm{~~(erg \\, s^{-1}),}}\r\n\\end{eqnarray*}$$with Bp in gauss, R* in centimetres, and Prot in seconds. In the above relation $W=2 \\pi R_{\\ast } \/ P_{\\mathrm{rot}} \\sqrt{G M_{\\ast }\/R_{\\ast }}$ is the dimensionless critical rotation parameter calculated as the ratio between the equatorial stellar velocity and the corresponding orbital velocity, defined by the gravitational law at the stellar equator (G = 6.67408 × 10−8 cm3 g−1 s−2 is the gravitational constant). Once the explicit relation of W is substituted within the LCBO definition, we find that $L_{\\mathrm{CBO}} \\propto {B_{\\mathrm{p}}^2 R_{\\ast }^{4.5} M_{\\ast }^{-0.5}} \/ {P_{\\mathrm{rot}}^2} \\propto L_{\\nu ,\\mathrm{rad}}$, which in practice is almost the same relation empirically found, except for the term related to the mass, that in any case has negligible effect. The maximum possible value of W is W = 1, which, due to magnetic braking, would have to be at the beginning of the star’s life; however no magnetic star has ever been found with W⪆0.5 (Shultz et al. 2019b). In fact, this parameter progressively decreases as the star loses angular momentum throughout its life (Keszthelyi et al. 2019, 2020).","Citation Text":["Owocki et al. (2022)"],"Citation Start End":[[652,672]]} {"Identifier":"2022MNRAS.515.5523L__Owocki_et_al._2022_Instance_2","Paragraph":"The behaviour of the radio emission from the early-type magnetic stars has been definitively quantified by the empirical scaling relationship between the radio spectral luminosity and the magnetic flux rate: $L_{\\nu ,\\mathrm{rad}} {\\propto } (\\Phi \/ P_{\\mathrm{rot}})^2 = {B_{\\mathrm{p}}^2 R_{\\ast }^{4}} \/ {P_{\\mathrm{rot}}^2}$, found by Leto et al. (2021) and confirmed by Shultz et al. (2022). This empirical relationship is the consequence of the physical mechanism supporting the non-thermal acceleration able to produce the electrons responsible for the magnetospheric radio emission of early-type magnetic stars. It was recently demonstrated by Owocki et al. (2022) that the power provided by centrifugal breakout events, continuously occurring within the stellar magnetosphere, is directly related to the power of the radio emission. From this point of view, the CBOs are non-random events. Breakouts occur continuously in a well-constrained magnetospheric region, where the resulting reconnection of the magnetic fields drives the acceleration of the local electrons. The CBO luminosity is related to the stellar parameters by the relation (Owocki et al. 2022): \n$$\\begin{eqnarray*}\r\nL_{\\mathrm{CBO}} = \\frac{B_{\\mathrm{p}}^2 R_{\\ast }^3}{P_{\\mathrm{rot}}} \\times W {\\mathrm{~~(erg \\, s^{-1}),}}\r\n\\end{eqnarray*}$$with Bp in gauss, R* in centimetres, and Prot in seconds. In the above relation $W=2 \\pi R_{\\ast } \/ P_{\\mathrm{rot}} \\sqrt{G M_{\\ast }\/R_{\\ast }}$ is the dimensionless critical rotation parameter calculated as the ratio between the equatorial stellar velocity and the corresponding orbital velocity, defined by the gravitational law at the stellar equator (G = 6.67408 × 10−8 cm3 g−1 s−2 is the gravitational constant). Once the explicit relation of W is substituted within the LCBO definition, we find that $L_{\\mathrm{CBO}} \\propto {B_{\\mathrm{p}}^2 R_{\\ast }^{4.5} M_{\\ast }^{-0.5}} \/ {P_{\\mathrm{rot}}^2} \\propto L_{\\nu ,\\mathrm{rad}}$, which in practice is almost the same relation empirically found, except for the term related to the mass, that in any case has negligible effect. The maximum possible value of W is W = 1, which, due to magnetic braking, would have to be at the beginning of the star’s life; however no magnetic star has ever been found with W⪆0.5 (Shultz et al. 2019b). In fact, this parameter progressively decreases as the star loses angular momentum throughout its life (Keszthelyi et al. 2019, 2020).","Citation Text":["Owocki et al. 2022"],"Citation Start End":[[1150,1168]]} {"Identifier":"2016ApJ...827...99T__Dere_et_al._1984_Instance_1","Paragraph":"The presence of neutral lines in the IRIS spectra allow us an accurate absolute wavelength calibration, and therefore a more accurate determination of line Doppler shifts, as compared to some other spectral observations; e.g., with EIS. For the post-flare loops, we find that the Fe xii emission is largely unshifted at the loop tops and predominantly redshifted at both loop footpoints, as expected for the draining of plasma in the later phases of the flare, when the heating has ceased. For the moss observations, we find that the distribution of Doppler shifts is peaked at a redshift of a few km s−1, but with significant wings on both the red and the blue sides. In our interpretation, guided by the Bifrost 3D models, Fe xii appears redshifted for hotter coronal temperatures (≳4 MK), while blueshifted when the corona is at cooler temperatures. The distribution of Doppler shift we observe shows a wide range of blue- and redshifts, and it suggests that there may be a continuous mix of heating and cooling in the moss we observed. For cooler TR lines (\n\n\n\n\n\n[K]\n\n\n\n\n\n), the dominance of redshift is well established (e.g., Doschek et al. 1976; Dere et al. 1984; Achour et al. 1995; Chae et al. 1998b; Peter & Judge 1999). The physical processes causing the observed redshifts are still debated, and several models have been proposed (e.g., Hansteen 1993; Patsourakos & Klimchuk 2006; Peter et al. 2006; Hansteen et al. 2010). Hansteen et al. (2010) use 3D radiative MHD models of the solar atmosphere to investigate the TR redshifts, and find that in their model the heating is dominated by rapid intermittent events at low heights which heat the plasma locally to coronal temperature and produces downflows at TR temperature due to the local overpressure. The model analyzed by Hansteen et al. (2010) reached modest coronal temperatures (≲2.5 MK), therefore with significant Fe xii emission in loop structures rather than at the loop footpoints, as in the case for moss. Here we used a different Bifrost 3D MHD simulation, which reaches higher coronal temperatures and represents a better model for moss observations. We find that the moss Fe xii (mostly) redshifted emission we observe with IRIS is reproduced in the model when the corona gets hot enough and most of the Fe xii is confined in the TR loops. The Fe xii then behaves like a TR line, and is redshifted, in the model, as a consequence of the local heating at low heights which causes upflows in the hotter lines and downflows in the cooler (TR) lines.","Citation Text":["Dere et al. 1984"],"Citation Start End":[[1153,1169]]} {"Identifier":"2015MNRAS.454.3886M__Zank_et_al._1996_Instance_1","Paragraph":"After crossing the bow shock, neutral atoms can interact with the shocked protons. The interaction length is given by\n\n(2)\n\n\\begin{equation}\n\\lambda = \\frac{V_{\\rm NS}}{X_{\\rm ion} n_{\\rm ISM} r_{\\rm c} \\langle \\sigma (v_{\\rm rel}) v_{\\rm rel} \\rangle },\n\\end{equation}\n\nwhere Xion is the ionization fraction of the ISM, rc is the compression ratio of the bow shock, σ(vrel) is the relevant cross-section of the process under consideration and 〈σvrel〉 is the collision rate averaged over the ion distribution function. When the ion distribution is a Maxwellian, 〈σvrel〉 is well approximated (within 20 per cent) by the expression (Zank et al. 1996; Blasi et al. 2012)\n\n(3)\n\n\\begin{equation}\n\\langle \\sigma v_{{\\rm rel}} \\rangle \\approx \\sigma (U^*) U^*,\n\\end{equation}\n\nwhere\n\n(4)\n\n\\begin{equation}\nU^*= \\sqrt{\\frac{8}{\\pi } \\frac{2 k_{\\rm B} T}{m_{\\rm p}} }\n\\end{equation}\n\nis the average, relative speed between the incoming hydrogen atom and ions (T is the temperature of the shocked ISM determined by the Rankine–Hugoniot jump conditions, assumed to be ≫TISM). Using the fiducial values nISM = 0.1 cm−3 and VNS = 300 km s−1, together with an ionization fraction of 90 per cent and rc = 4 (the typical value for strong shocks), leads to the following estimates for the mean free paths:\n\n(5)\n\n\\begin{eqnarray}\n\\lambda _{{\\rm ion},{\\rm p}} & \\approx 3.0 \\times 10^{20} \\, \\rm cm,\n\\end{eqnarray}\n\n\n(6)\n\n\\begin{eqnarray}\n\\lambda _{{\\rm ion},{\\rm e}} & \\approx 2.2 \\times 10^{16} \\, \\rm cm,\n\\end{eqnarray}\n\n\n(7)\n\n\\begin{eqnarray}\n\\lambda _{\\rm CE} & \\approx 1.5 \\times 10^{15} \\, \\rm cm\n\\end{eqnarray}\n\nfor the ionization due to collisions with protons, electrons and CE, respectively. Note that λion, e has been calculated under the assumption that the electrons downstream of the shock equilibrate rapidly with protons, thereby acquiring the same temperature. If this assumption does not hold, the collisional length scale for ionization due to electrons can become much larger than the value reported in equation (6). In addition, the values (5)–(7) are to be taken as lower limits as they are valid just ahead of the nebula, where the compression ratio and the temperature obtain their maximum values.","Citation Text":["Zank et al. 1996"],"Citation Start End":[[631,647]]} {"Identifier":"2019ApJ...873...22S__Patsourakos_&_Vourlidas_2009_Instance_1","Paragraph":"The driving mechanism and physical nature of large-scale EUV waves have been hotly debated over the past 20 years (Chen 2017). Because chromospheric Moreton waves were believed to be driven by the flare pressure pulses for a long time after Uchida (1968), solar physicists naturally thought at the beginning that EUV waves also have the same driving mechanism (e.g., Khan & Aurass 2002; Hudson et al. 2003; Warmuth et al. 2004). However, more and more recent high-resolution observational studies have shown that EUV waves are in fact bow shocks driven by CMEs instead of flare pressure pulses (e.g., Chen 2006; Kienreich et al. 2009; Patsourakos & Vourlidas 2009; Patsourakos et al. 2010; Liu et al. 2011b; Shen & Liu 2012a, 2012c; Xue et al. 2013; Long et al. 2017a; Shen et al. 2017a; Cunha-Silva et al. 2018). Further investigations indicated that EUV waves can also be excited by other kinds of slightly different processes, such as newly formed expanding loops, coronal jets, and mini-filament eruptions on small scales (e.g., Podladchikova et al. 2010; Zheng et al. 2012, 2013; Su et al. 2015; Shen et al. 2017a), and the sudden expansion of transequatorial loops driven by coronal jets on large scales (Shen et al. 2018e, 2018d). In these scenarios, those authors found that such EUV waves often have a shorter lifetime (a few minutes) compared to those driven by CMEs (tens of minutes). Moreover, Shen et al. (2018a) reported an interesting non-CME-associated homologous EUV wave event in which the initial speeds of the waves are about 1000 km s−1, and the authors proposed that the observed EUV waves were large-amplitude nonlinear fast-mode magnetosonic waves or shocks directly driven by the associated recurrent coronal jets, resembling the generation of a piston shock in a tube. These new observations suggest that EUV waves can be excited by different kinds of coronal disturbances, e.g., CMEs, coronal jets, and mini-filament eruptions.","Citation Text":["Patsourakos & Vourlidas 2009"],"Citation Start End":[[635,663]]} {"Identifier":"2019ApJ...873...22SShen_et_al._2018e_Instance_1","Paragraph":"The driving mechanism and physical nature of large-scale EUV waves have been hotly debated over the past 20 years (Chen 2017). Because chromospheric Moreton waves were believed to be driven by the flare pressure pulses for a long time after Uchida (1968), solar physicists naturally thought at the beginning that EUV waves also have the same driving mechanism (e.g., Khan & Aurass 2002; Hudson et al. 2003; Warmuth et al. 2004). However, more and more recent high-resolution observational studies have shown that EUV waves are in fact bow shocks driven by CMEs instead of flare pressure pulses (e.g., Chen 2006; Kienreich et al. 2009; Patsourakos & Vourlidas 2009; Patsourakos et al. 2010; Liu et al. 2011b; Shen & Liu 2012a, 2012c; Xue et al. 2013; Long et al. 2017a; Shen et al. 2017a; Cunha-Silva et al. 2018). Further investigations indicated that EUV waves can also be excited by other kinds of slightly different processes, such as newly formed expanding loops, coronal jets, and mini-filament eruptions on small scales (e.g., Podladchikova et al. 2010; Zheng et al. 2012, 2013; Su et al. 2015; Shen et al. 2017a), and the sudden expansion of transequatorial loops driven by coronal jets on large scales (Shen et al. 2018e, 2018d). In these scenarios, those authors found that such EUV waves often have a shorter lifetime (a few minutes) compared to those driven by CMEs (tens of minutes). Moreover, Shen et al. (2018a) reported an interesting non-CME-associated homologous EUV wave event in which the initial speeds of the waves are about 1000 km s−1, and the authors proposed that the observed EUV waves were large-amplitude nonlinear fast-mode magnetosonic waves or shocks directly driven by the associated recurrent coronal jets, resembling the generation of a piston shock in a tube. These new observations suggest that EUV waves can be excited by different kinds of coronal disturbances, e.g., CMEs, coronal jets, and mini-filament eruptions.","Citation Text":["Shen et al. 2018e"],"Citation Start End":[[1211,1228]]} {"Identifier":"2019ApJ...873...22SShen_et_al._(2018a)_Instance_1","Paragraph":"The driving mechanism and physical nature of large-scale EUV waves have been hotly debated over the past 20 years (Chen 2017). Because chromospheric Moreton waves were believed to be driven by the flare pressure pulses for a long time after Uchida (1968), solar physicists naturally thought at the beginning that EUV waves also have the same driving mechanism (e.g., Khan & Aurass 2002; Hudson et al. 2003; Warmuth et al. 2004). However, more and more recent high-resolution observational studies have shown that EUV waves are in fact bow shocks driven by CMEs instead of flare pressure pulses (e.g., Chen 2006; Kienreich et al. 2009; Patsourakos & Vourlidas 2009; Patsourakos et al. 2010; Liu et al. 2011b; Shen & Liu 2012a, 2012c; Xue et al. 2013; Long et al. 2017a; Shen et al. 2017a; Cunha-Silva et al. 2018). Further investigations indicated that EUV waves can also be excited by other kinds of slightly different processes, such as newly formed expanding loops, coronal jets, and mini-filament eruptions on small scales (e.g., Podladchikova et al. 2010; Zheng et al. 2012, 2013; Su et al. 2015; Shen et al. 2017a), and the sudden expansion of transequatorial loops driven by coronal jets on large scales (Shen et al. 2018e, 2018d). In these scenarios, those authors found that such EUV waves often have a shorter lifetime (a few minutes) compared to those driven by CMEs (tens of minutes). Moreover, Shen et al. (2018a) reported an interesting non-CME-associated homologous EUV wave event in which the initial speeds of the waves are about 1000 km s−1, and the authors proposed that the observed EUV waves were large-amplitude nonlinear fast-mode magnetosonic waves or shocks directly driven by the associated recurrent coronal jets, resembling the generation of a piston shock in a tube. These new observations suggest that EUV waves can be excited by different kinds of coronal disturbances, e.g., CMEs, coronal jets, and mini-filament eruptions.","Citation Text":["Shen et al. (2018a)"],"Citation Start End":[[1406,1425]]} {"Identifier":"2020MNRAS.493..559B__Etangs_et_al._2010_Instance_1","Paragraph":"The HD 189733 system offers the possibility to study these various interactions (Table 1). It is a binary system with a K2V dwarf (HD 189733 A, hereafter HD 189733) and a M4V dwarf (HD 189733 B; Bakos et al. 2006) at a mean separation of ∼220 au. The bright primary (V = 7.7) hosts a transiting hot Jupiter at 0.03 au (Bouchy et al. 2005), whose strong irradiation and large occultation area make it particularly favourable for atmospheric characterization (see Pino et al. 2018 and references inside for observations of the lower atmospheric layers). Recent transit observations in the near-infrared (Salz et al. 2018) revealed absorption by helium in an extended but compact thermosphere. Transit observations in the far-ultraviolet (FUV) previously revealed absorption by a dense and hot layer of neutral oxygen at higher altitudes (Ben-Jaffel & Ballester 2013). The close distance of HD 189733 to the Sun (19.8 pc) enables observations of the stellar Lyman α line with the Hubble Space Telescope (HST). Atmospheric escape of neutral hydrogen was first detected in the unresolved line with the HST Advanced Camera for Surveys (ACS) in two out of three epochs (Lecavelier des Etangs et al. 2010), and in the line resolved with the HST Space Telescope Imaging Spectrograph (STIS) in one out of two epochs (Lecavelier des Etangs et al. 2012; Bourrier et al. 2013). These observations provided the first indication of temporal variations in the physical conditions of an evaporating planetary atmosphere. Bourrier & Lecavelier des Etangs (2013) attributed the high-velocity, blueshifted absorption signature detected by Lecavelier des Etangs et al. (2012) to intense charge-exchange between the planet exosphere and the stellar wind, proposing that an X-ray flare observed before the transit increased the atmospheric mass-loss and\/or increased the density of the stellar wind. The latter scenario is favoured by thermal escape simulations from Chadney et al. (2017), who found that the energy input from a flare would not increase sufficiently the mass-loss. Interestingly the tentative detection of absorption by ionized carbon (Ben-Jaffel & Ballester 2013) and excited hydrogen (Jensen et al. 2012; Cauley et al. 2015, 2016; Cauley, Redfield & Jensen 2017; Kohl et al. 2018) before and during the transit of HD 189733b could be explained by the interaction of the stellar wind with the planetary magnetosphere or escaping material. The observed temporal variability in the atmospheric escape of neutral and excited hydrogen is likely linked to the high-level of activity from the host star, which results in a fast-changing radiation, particle, and magnetic environment for the planet. Enhanced activity in the stellar chromosphere and transition region have also been observed after the planetary eclipse, and attributed to signatures of magnetic star–planet interactions (Pillitteri et al. 2010, 2011, 2014, 2015). Evidence for modulation in the Ca ii lines at the orbital period of the planet, during an epoch of strong stellar magnetic field, further supports this scenario (Cauley et al. 2018). The detectability of star–planet interactions in the HD 189733 system however remain uncertain, and intrinsic stellar variability and inadequate sampling has been proposed to explain the observed variations (Route 2019). These results show the need to study contemporaneously and in different epochs the upper atmosphere of HD 189733b and its high-energy environment.","Citation Text":["Lecavelier des Etangs et al. 2010"],"Citation Start End":[[1163,1196]]} {"Identifier":"2022MNRAS.509.3488I__Kormendy_1988_Instance_1","Paragraph":"Due to recent major advances in the observational studies of active galactic nuclei (AGN), evidence is growing that massive black holes (MBHs) heavier than $10^5\\, \\rm {M_\\odot }$ form in nature and power AGN activity at the centres of galaxies through gas accretion (Schmidt 1963; Hopkins, Richards & Hernquist 2007; Merloni & Heinz 2008; Ueda et al. 2014; Aird et al. 2015). The demographic study of AGN and the dynamics of stars and gas around the centre of nearby galaxies, further provided evidence that most (if not all) massive galaxies in the Universe host MBHs in their nuclei (Genzel & Townes 1987; Dressler & Richstone 1988; Kormendy 1988; Kormendy & Richstone 1992; Genzel, Hollenbach & Townes 1994; Salucci et al. 1999; Peterson et al. 2004; Vestergaard & Peterson 2006). Even more, the existing correlations between the mass of MBHs and key properties of their host galaxies hint for their co-evolution (Haehnelt & Rees 1993; Faber 1999; O’Dowd, Urry & Scarpa 2002; Häring & Rix 2004; Kormendy & Ho 2013; Savorgnan et al. 2016). Even though these findings sharpened our knowledge on the role of MBHs in the formation and evolution of galaxies, there is a need to contextualize galaxies and MBHs within the broad cosmological context. It is commonly accepted that the Universe behaves in a hierarchical way. Cosmic structure formed through the hierarchical assembly of dark matter (DM) haloes, and the galaxies observed nowadays assembled through mergers with smaller companions and accretion of matter from the cosmic filaments (White & Rees 1978; White & Frenk 1991; Haehnelt & Rees 1993; Kauffmann et al. 1999; Guo et al. 2011; Vogelsberger et al. 2014a,b; Schaye et al. 2015; Nelson et al. 2018; Pillepich et al. 2018). Consequently, the existence of MBHs at the centre of galaxies and the main role of mergers in the Universe, hint for the existence of massive black hole binary systems (MBHBs) that might have formed and coalesced throughout the whole Universe lifetime.","Citation Text":["Kormendy 1988","O’Dowd, Urry & Scarpa 2002"],"Citation Start End":[[636,649],[952,978]]} {"Identifier":"2022MNRAS.509.3488IUeda_et_al._2014_Instance_1","Paragraph":"Due to recent major advances in the observational studies of active galactic nuclei (AGN), evidence is growing that massive black holes (MBHs) heavier than $10^5\\, \\rm {M_\\odot }$ form in nature and power AGN activity at the centres of galaxies through gas accretion (Schmidt 1963; Hopkins, Richards & Hernquist 2007; Merloni & Heinz 2008; Ueda et al. 2014; Aird et al. 2015). The demographic study of AGN and the dynamics of stars and gas around the centre of nearby galaxies, further provided evidence that most (if not all) massive galaxies in the Universe host MBHs in their nuclei (Genzel & Townes 1987; Dressler & Richstone 1988; Kormendy 1988; Kormendy & Richstone 1992; Genzel, Hollenbach & Townes 1994; Salucci et al. 1999; Peterson et al. 2004; Vestergaard & Peterson 2006). Even more, the existing correlations between the mass of MBHs and key properties of their host galaxies hint for their co-evolution (Haehnelt & Rees 1993; Faber 1999; O’Dowd, Urry & Scarpa 2002; Häring & Rix 2004; Kormendy & Ho 2013; Savorgnan et al. 2016). Even though these findings sharpened our knowledge on the role of MBHs in the formation and evolution of galaxies, there is a need to contextualize galaxies and MBHs within the broad cosmological context. It is commonly accepted that the Universe behaves in a hierarchical way. Cosmic structure formed through the hierarchical assembly of dark matter (DM) haloes, and the galaxies observed nowadays assembled through mergers with smaller companions and accretion of matter from the cosmic filaments (White & Rees 1978; White & Frenk 1991; Haehnelt & Rees 1993; Kauffmann et al. 1999; Guo et al. 2011; Vogelsberger et al. 2014a,b; Schaye et al. 2015; Nelson et al. 2018; Pillepich et al. 2018). Consequently, the existence of MBHs at the centre of galaxies and the main role of mergers in the Universe, hint for the existence of massive black hole binary systems (MBHBs) that might have formed and coalesced throughout the whole Universe lifetime.","Citation Text":["Ueda et al. 2014"],"Citation Start End":[[340,356]]} {"Identifier":"2022MNRAS.509.3488IKauffmann_et_al._1999_Instance_1","Paragraph":"Due to recent major advances in the observational studies of active galactic nuclei (AGN), evidence is growing that massive black holes (MBHs) heavier than $10^5\\, \\rm {M_\\odot }$ form in nature and power AGN activity at the centres of galaxies through gas accretion (Schmidt 1963; Hopkins, Richards & Hernquist 2007; Merloni & Heinz 2008; Ueda et al. 2014; Aird et al. 2015). The demographic study of AGN and the dynamics of stars and gas around the centre of nearby galaxies, further provided evidence that most (if not all) massive galaxies in the Universe host MBHs in their nuclei (Genzel & Townes 1987; Dressler & Richstone 1988; Kormendy 1988; Kormendy & Richstone 1992; Genzel, Hollenbach & Townes 1994; Salucci et al. 1999; Peterson et al. 2004; Vestergaard & Peterson 2006). Even more, the existing correlations between the mass of MBHs and key properties of their host galaxies hint for their co-evolution (Haehnelt & Rees 1993; Faber 1999; O’Dowd, Urry & Scarpa 2002; Häring & Rix 2004; Kormendy & Ho 2013; Savorgnan et al. 2016). Even though these findings sharpened our knowledge on the role of MBHs in the formation and evolution of galaxies, there is a need to contextualize galaxies and MBHs within the broad cosmological context. It is commonly accepted that the Universe behaves in a hierarchical way. Cosmic structure formed through the hierarchical assembly of dark matter (DM) haloes, and the galaxies observed nowadays assembled through mergers with smaller companions and accretion of matter from the cosmic filaments (White & Rees 1978; White & Frenk 1991; Haehnelt & Rees 1993; Kauffmann et al. 1999; Guo et al. 2011; Vogelsberger et al. 2014a,b; Schaye et al. 2015; Nelson et al. 2018; Pillepich et al. 2018). Consequently, the existence of MBHs at the centre of galaxies and the main role of mergers in the Universe, hint for the existence of massive black hole binary systems (MBHBs) that might have formed and coalesced throughout the whole Universe lifetime.","Citation Text":["Kauffmann et al. 1999"],"Citation Start End":[[1604,1625]]} {"Identifier":"2019ApJ...871L..10E__Zhao_et_al._2010_Instance_1","Paragraph":"The two components in V593 Cen are early-type stars that contain the convective core and the radiative envelope. This suggests that the period oscillation cannot be explained by the magnetic activity cycle mechanism, which is usually adopted to explain the cycle period change of later-type binary stars (e.g., Applegate 1992; Lanza et al. 1998). Therefore, the light-travel-time effect via the presence of a tertiary body is adopted to explain the cyclic change of the orbital period (e.g., Irwin 1952; Chambliss 1992; Borkovits & Hegedüs 1996; Liao & Qian 2010). Using this method, tertiary bodies have been detected orbiting massive close binary stars. Some examples are V701 Sco (Qian et al. 2006), V382 Cyg, TU Mus (Qian et al. 2007), and AI Cru (Zhao et al. 2010). Though it seems that binaries favor a more uniform distribution of eccentricities (Tokovinin 1997, 2008; Raghavan et al. 2010; Moe & Di Stefano 2017), we still assume that the tertiary wanders in the circular orbit. This is because the period change (in Figure 2) displays a periodic oscillation, and this oscillation is fitted either by a sine curve without eccentricities, or by using the value of the outer orbital period and the inner binary period (Pouter and Pinner). The period ratio for this multiple system is about Pouter\/Pinner = 2.5 × 104. For this kind of multiple star system with a very large period ratio, the outer orbit usually has very low or no eccentricities (Shatsky 2001; Tokovinin 2004, 2008). Moreover, in large Pouter\/Pinner ratio multiple system (commonly found in triple systems) the Kozai effect becomes too weak (Tokovinin 2008). For brevity, considering that the third body in the V593 Cen system is moving in a circular orbit, the projected radius of the orbit of the eclipsing pair rotating around the mass central of the triple system, the mass function, and the masses of the third component could be computed with these equations as follows:\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere A3 is the amplitude of the O − C oscillation, c is the light speed, P3 is the period of the O − C oscillation, and i′ is the inclination of the tertiary orbital plane. Finally, when the inclination i′ = 90°, it is calculated that the lowest mass of the tertiary companion is 4.3 (0.3) M⊙ and the separation between the binary and the tertiary companion is about 25.5(2.2) au. For the other inclinations, the third body should have a larger mass and a shorter separation. When the inclination i′ = 826, which shows that the third body is in the same plane with the inner binary, its mass is calculated to be 4.7 (0.4) M⊙ and the separation is 25.2(2.8) au.","Citation Text":["Zhao et al. 2010"],"Citation Start End":[[752,768]]} {"Identifier":"2019ApJ...871L..10EShatsky_2001_Instance_1","Paragraph":"The two components in V593 Cen are early-type stars that contain the convective core and the radiative envelope. This suggests that the period oscillation cannot be explained by the magnetic activity cycle mechanism, which is usually adopted to explain the cycle period change of later-type binary stars (e.g., Applegate 1992; Lanza et al. 1998). Therefore, the light-travel-time effect via the presence of a tertiary body is adopted to explain the cyclic change of the orbital period (e.g., Irwin 1952; Chambliss 1992; Borkovits & Hegedüs 1996; Liao & Qian 2010). Using this method, tertiary bodies have been detected orbiting massive close binary stars. Some examples are V701 Sco (Qian et al. 2006), V382 Cyg, TU Mus (Qian et al. 2007), and AI Cru (Zhao et al. 2010). Though it seems that binaries favor a more uniform distribution of eccentricities (Tokovinin 1997, 2008; Raghavan et al. 2010; Moe & Di Stefano 2017), we still assume that the tertiary wanders in the circular orbit. This is because the period change (in Figure 2) displays a periodic oscillation, and this oscillation is fitted either by a sine curve without eccentricities, or by using the value of the outer orbital period and the inner binary period (Pouter and Pinner). The period ratio for this multiple system is about Pouter\/Pinner = 2.5 × 104. For this kind of multiple star system with a very large period ratio, the outer orbit usually has very low or no eccentricities (Shatsky 2001; Tokovinin 2004, 2008). Moreover, in large Pouter\/Pinner ratio multiple system (commonly found in triple systems) the Kozai effect becomes too weak (Tokovinin 2008). For brevity, considering that the third body in the V593 Cen system is moving in a circular orbit, the projected radius of the orbit of the eclipsing pair rotating around the mass central of the triple system, the mass function, and the masses of the third component could be computed with these equations as follows:\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere A3 is the amplitude of the O − C oscillation, c is the light speed, P3 is the period of the O − C oscillation, and i′ is the inclination of the tertiary orbital plane. Finally, when the inclination i′ = 90°, it is calculated that the lowest mass of the tertiary companion is 4.3 (0.3) M⊙ and the separation between the binary and the tertiary companion is about 25.5(2.2) au. For the other inclinations, the third body should have a larger mass and a shorter separation. When the inclination i′ = 826, which shows that the third body is in the same plane with the inner binary, its mass is calculated to be 4.7 (0.4) M⊙ and the separation is 25.2(2.8) au.","Citation Text":["Shatsky 2001"],"Citation Start End":[[1452,1464]]} {"Identifier":"2019ApJ...871L..10EApplegate_1992_Instance_1","Paragraph":"The two components in V593 Cen are early-type stars that contain the convective core and the radiative envelope. This suggests that the period oscillation cannot be explained by the magnetic activity cycle mechanism, which is usually adopted to explain the cycle period change of later-type binary stars (e.g., Applegate 1992; Lanza et al. 1998). Therefore, the light-travel-time effect via the presence of a tertiary body is adopted to explain the cyclic change of the orbital period (e.g., Irwin 1952; Chambliss 1992; Borkovits & Hegedüs 1996; Liao & Qian 2010). Using this method, tertiary bodies have been detected orbiting massive close binary stars. Some examples are V701 Sco (Qian et al. 2006), V382 Cyg, TU Mus (Qian et al. 2007), and AI Cru (Zhao et al. 2010). Though it seems that binaries favor a more uniform distribution of eccentricities (Tokovinin 1997, 2008; Raghavan et al. 2010; Moe & Di Stefano 2017), we still assume that the tertiary wanders in the circular orbit. This is because the period change (in Figure 2) displays a periodic oscillation, and this oscillation is fitted either by a sine curve without eccentricities, or by using the value of the outer orbital period and the inner binary period (Pouter and Pinner). The period ratio for this multiple system is about Pouter\/Pinner = 2.5 × 104. For this kind of multiple star system with a very large period ratio, the outer orbit usually has very low or no eccentricities (Shatsky 2001; Tokovinin 2004, 2008). Moreover, in large Pouter\/Pinner ratio multiple system (commonly found in triple systems) the Kozai effect becomes too weak (Tokovinin 2008). For brevity, considering that the third body in the V593 Cen system is moving in a circular orbit, the projected radius of the orbit of the eclipsing pair rotating around the mass central of the triple system, the mass function, and the masses of the third component could be computed with these equations as follows:\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere A3 is the amplitude of the O − C oscillation, c is the light speed, P3 is the period of the O − C oscillation, and i′ is the inclination of the tertiary orbital plane. Finally, when the inclination i′ = 90°, it is calculated that the lowest mass of the tertiary companion is 4.3 (0.3) M⊙ and the separation between the binary and the tertiary companion is about 25.5(2.2) au. For the other inclinations, the third body should have a larger mass and a shorter separation. When the inclination i′ = 826, which shows that the third body is in the same plane with the inner binary, its mass is calculated to be 4.7 (0.4) M⊙ and the separation is 25.2(2.8) au.","Citation Text":["Applegate 1992"],"Citation Start End":[[311,325]]} {"Identifier":"2021MNRAS.500.2577K__Alecian_et_al._2015_Instance_1","Paragraph":"The binary characteristics of early-type magnetic stars may provide crucial clues, allowing one to test alternative fossil field hypotheses. The non-magnetic chemically peculiar stars of Am (A-type stars with enhanced lines of Fe-peak elements) and HgMn (late-B stars identified by strong lines of Hg and\/or Mn) types are frequently found in close binaries (Gerbaldi, Floquet & Hauck 1985; Ryabchikova 1998; Carquillat & Prieur 2007), including eclipsing systems (Nordstrom & Johansen 1994; Strassmeier et al. 2017; Takeda et al. 2019). In contrast, only about ten close (Porb 20 d) spectroscopic binaries containing at least one magnetic ApBp star are known (Landstreet et al. 2017). The overall incidence rate of magnetic upper main sequence stars in close binaries is less than 2 per cent (Alecian et al. 2015), although this fraction is significantly higher if one includes wide long-period systems (Mathys 2017). This low incidence of magnetic ApBp stars in close binaries is frequently considered as an argument in favour of the stellar merger origin of fossil fields (de Mink et al. 2014; Schneider et al. 2016). In this context, confirmation of magnetic ApBp stars in short-period binary systems gives support to alternative theories or, at least, demonstrates that early-type stars may acquire magnetic fields through different channels. In addition, detached close binary stars, particularly those showing eclipses, are valuable astrophysical laboratories that provide model-independent stellar parameters and allow one to study pairs of co-evolving stars formed in the same environment. Until recently, no early-type magnetic stars in eclipsing binaries were known. The first such system, HD 66051, was identified by Kochukhov et al. (2018). The second system, HD 62658 containing twin components of which only one is magnetic, was found by Shultz et al. (2019). Several other eclipsing binaries containing candidate ApBp stars were proposed (Hensberge et al. 2007; González, Hubrig & Castelli 2010; Skarka et al. 2019), but the magnetic nature of these stars has not been verified by direct detections of their fields using the Zeeman effect. In this paper, we put a spotlight on another candidate eclipsing magnetic Bp star, which received little attention prior to our work despite being significantly brighter than the confirmed magnetic eclipsing systems HD 62658 and HD 66051.","Citation Text":["Alecian et al. 2015"],"Citation Start End":[[794,813]]} {"Identifier":"2021MNRAS.500.2577KKochukhov_et_al._(2018)_Instance_1","Paragraph":"The binary characteristics of early-type magnetic stars may provide crucial clues, allowing one to test alternative fossil field hypotheses. The non-magnetic chemically peculiar stars of Am (A-type stars with enhanced lines of Fe-peak elements) and HgMn (late-B stars identified by strong lines of Hg and\/or Mn) types are frequently found in close binaries (Gerbaldi, Floquet & Hauck 1985; Ryabchikova 1998; Carquillat & Prieur 2007), including eclipsing systems (Nordstrom & Johansen 1994; Strassmeier et al. 2017; Takeda et al. 2019). In contrast, only about ten close (Porb 20 d) spectroscopic binaries containing at least one magnetic ApBp star are known (Landstreet et al. 2017). The overall incidence rate of magnetic upper main sequence stars in close binaries is less than 2 per cent (Alecian et al. 2015), although this fraction is significantly higher if one includes wide long-period systems (Mathys 2017). This low incidence of magnetic ApBp stars in close binaries is frequently considered as an argument in favour of the stellar merger origin of fossil fields (de Mink et al. 2014; Schneider et al. 2016). In this context, confirmation of magnetic ApBp stars in short-period binary systems gives support to alternative theories or, at least, demonstrates that early-type stars may acquire magnetic fields through different channels. In addition, detached close binary stars, particularly those showing eclipses, are valuable astrophysical laboratories that provide model-independent stellar parameters and allow one to study pairs of co-evolving stars formed in the same environment. Until recently, no early-type magnetic stars in eclipsing binaries were known. The first such system, HD 66051, was identified by Kochukhov et al. (2018). The second system, HD 62658 containing twin components of which only one is magnetic, was found by Shultz et al. (2019). Several other eclipsing binaries containing candidate ApBp stars were proposed (Hensberge et al. 2007; González, Hubrig & Castelli 2010; Skarka et al. 2019), but the magnetic nature of these stars has not been verified by direct detections of their fields using the Zeeman effect. In this paper, we put a spotlight on another candidate eclipsing magnetic Bp star, which received little attention prior to our work despite being significantly brighter than the confirmed magnetic eclipsing systems HD 62658 and HD 66051.","Citation Text":["Kochukhov et al. (2018)"],"Citation Start End":[[1729,1752]]} {"Identifier":"2021MNRAS.500.2577KShultz_et_al._(2019)_Instance_1","Paragraph":"The binary characteristics of early-type magnetic stars may provide crucial clues, allowing one to test alternative fossil field hypotheses. The non-magnetic chemically peculiar stars of Am (A-type stars with enhanced lines of Fe-peak elements) and HgMn (late-B stars identified by strong lines of Hg and\/or Mn) types are frequently found in close binaries (Gerbaldi, Floquet & Hauck 1985; Ryabchikova 1998; Carquillat & Prieur 2007), including eclipsing systems (Nordstrom & Johansen 1994; Strassmeier et al. 2017; Takeda et al. 2019). In contrast, only about ten close (Porb 20 d) spectroscopic binaries containing at least one magnetic ApBp star are known (Landstreet et al. 2017). The overall incidence rate of magnetic upper main sequence stars in close binaries is less than 2 per cent (Alecian et al. 2015), although this fraction is significantly higher if one includes wide long-period systems (Mathys 2017). This low incidence of magnetic ApBp stars in close binaries is frequently considered as an argument in favour of the stellar merger origin of fossil fields (de Mink et al. 2014; Schneider et al. 2016). In this context, confirmation of magnetic ApBp stars in short-period binary systems gives support to alternative theories or, at least, demonstrates that early-type stars may acquire magnetic fields through different channels. In addition, detached close binary stars, particularly those showing eclipses, are valuable astrophysical laboratories that provide model-independent stellar parameters and allow one to study pairs of co-evolving stars formed in the same environment. Until recently, no early-type magnetic stars in eclipsing binaries were known. The first such system, HD 66051, was identified by Kochukhov et al. (2018). The second system, HD 62658 containing twin components of which only one is magnetic, was found by Shultz et al. (2019). Several other eclipsing binaries containing candidate ApBp stars were proposed (Hensberge et al. 2007; González, Hubrig & Castelli 2010; Skarka et al. 2019), but the magnetic nature of these stars has not been verified by direct detections of their fields using the Zeeman effect. In this paper, we put a spotlight on another candidate eclipsing magnetic Bp star, which received little attention prior to our work despite being significantly brighter than the confirmed magnetic eclipsing systems HD 62658 and HD 66051.","Citation Text":["Shultz et al. (2019)"],"Citation Start End":[[1853,1873]]} {"Identifier":"2021MNRAS.500.2577KGerbaldi,_Floquet_&_Hauck_1985_Instance_1","Paragraph":"The binary characteristics of early-type magnetic stars may provide crucial clues, allowing one to test alternative fossil field hypotheses. The non-magnetic chemically peculiar stars of Am (A-type stars with enhanced lines of Fe-peak elements) and HgMn (late-B stars identified by strong lines of Hg and\/or Mn) types are frequently found in close binaries (Gerbaldi, Floquet & Hauck 1985; Ryabchikova 1998; Carquillat & Prieur 2007), including eclipsing systems (Nordstrom & Johansen 1994; Strassmeier et al. 2017; Takeda et al. 2019). In contrast, only about ten close (Porb 20 d) spectroscopic binaries containing at least one magnetic ApBp star are known (Landstreet et al. 2017). The overall incidence rate of magnetic upper main sequence stars in close binaries is less than 2 per cent (Alecian et al. 2015), although this fraction is significantly higher if one includes wide long-period systems (Mathys 2017). This low incidence of magnetic ApBp stars in close binaries is frequently considered as an argument in favour of the stellar merger origin of fossil fields (de Mink et al. 2014; Schneider et al. 2016). In this context, confirmation of magnetic ApBp stars in short-period binary systems gives support to alternative theories or, at least, demonstrates that early-type stars may acquire magnetic fields through different channels. In addition, detached close binary stars, particularly those showing eclipses, are valuable astrophysical laboratories that provide model-independent stellar parameters and allow one to study pairs of co-evolving stars formed in the same environment. Until recently, no early-type magnetic stars in eclipsing binaries were known. The first such system, HD 66051, was identified by Kochukhov et al. (2018). The second system, HD 62658 containing twin components of which only one is magnetic, was found by Shultz et al. (2019). Several other eclipsing binaries containing candidate ApBp stars were proposed (Hensberge et al. 2007; González, Hubrig & Castelli 2010; Skarka et al. 2019), but the magnetic nature of these stars has not been verified by direct detections of their fields using the Zeeman effect. In this paper, we put a spotlight on another candidate eclipsing magnetic Bp star, which received little attention prior to our work despite being significantly brighter than the confirmed magnetic eclipsing systems HD 62658 and HD 66051.","Citation Text":["Gerbaldi, Floquet & Hauck 1985"],"Citation Start End":[[358,388]]} {"Identifier":"2021MNRAS.500.2577KSchneider_et_al._2016_Instance_1","Paragraph":"The binary characteristics of early-type magnetic stars may provide crucial clues, allowing one to test alternative fossil field hypotheses. The non-magnetic chemically peculiar stars of Am (A-type stars with enhanced lines of Fe-peak elements) and HgMn (late-B stars identified by strong lines of Hg and\/or Mn) types are frequently found in close binaries (Gerbaldi, Floquet & Hauck 1985; Ryabchikova 1998; Carquillat & Prieur 2007), including eclipsing systems (Nordstrom & Johansen 1994; Strassmeier et al. 2017; Takeda et al. 2019). In contrast, only about ten close (Porb 20 d) spectroscopic binaries containing at least one magnetic ApBp star are known (Landstreet et al. 2017). The overall incidence rate of magnetic upper main sequence stars in close binaries is less than 2 per cent (Alecian et al. 2015), although this fraction is significantly higher if one includes wide long-period systems (Mathys 2017). This low incidence of magnetic ApBp stars in close binaries is frequently considered as an argument in favour of the stellar merger origin of fossil fields (de Mink et al. 2014; Schneider et al. 2016). In this context, confirmation of magnetic ApBp stars in short-period binary systems gives support to alternative theories or, at least, demonstrates that early-type stars may acquire magnetic fields through different channels. In addition, detached close binary stars, particularly those showing eclipses, are valuable astrophysical laboratories that provide model-independent stellar parameters and allow one to study pairs of co-evolving stars formed in the same environment. Until recently, no early-type magnetic stars in eclipsing binaries were known. The first such system, HD 66051, was identified by Kochukhov et al. (2018). The second system, HD 62658 containing twin components of which only one is magnetic, was found by Shultz et al. (2019). Several other eclipsing binaries containing candidate ApBp stars were proposed (Hensberge et al. 2007; González, Hubrig & Castelli 2010; Skarka et al. 2019), but the magnetic nature of these stars has not been verified by direct detections of their fields using the Zeeman effect. In this paper, we put a spotlight on another candidate eclipsing magnetic Bp star, which received little attention prior to our work despite being significantly brighter than the confirmed magnetic eclipsing systems HD 62658 and HD 66051.","Citation Text":["Schneider et al. 2016"],"Citation Start End":[[1097,1118]]} {"Identifier":"2015AandA...579A..53O__Dalgarno_&_Rudge_(1965)_Instance_1","Paragraph":"In our model atom, singlet and triplet terms are often separated, and thus we would\n like to estimate how this total cross-section is distributed among final spin states. We\n considered a representation where the spin of the Rydberg electron is coupled to the\n spin of the other electrons in the target atom Sc (assuming\n this to be a good quantum number) to give the total electronic spin of the Rydberg atom,\n S.\n Recoupling of angular momenta gives the required spin-changing scattering amplitude in\n terms of the singlet and triplet scattering amplitudes (i.e. in the representation in\n which the Rydberg electron spin and the hydrogen atom spin are coupled), and the\n differential cross-section for change of spin S → S′, S ≠ S′,\n is found to be \\begin{eqnarray} |f_{\\rm e}(p,\\theta,S \\rightarrow S')|^2 & = & \\frac{(2S'+1)}{8(2S_{\\rm c}+1)} |f^+ - f^-|^2 \\\\[3mm] & = &\\frac{(2S'+1)}{2(2S_{\\rm c}+1)} \\sigma_{\\rm exch} \\end{eqnarray}\n\n\n\n\n|\n\nf\n\ne\n\n\n(\np,θ,S\n→\n\nS\n\n′\n\n\n)\n\n|\n\n2\n\n\n\n\n\n\n=\n\n\n\n\n\n\n\n\n\n(\n2\n\nS\n\n′\n\n\n+\n1\n)\n\n\n8\n(\n2\n\nS\n\nc\n\n\n+\n1\n)\n\n\n\n\n\n|\n\nf\n\n+\n\n\n−\n\nf\n\n−\n\n\n\n|\n\n2\n\n\n\n\n\n\n\n\n\n\n\n\n=\n\n\n\n\n\n\n\n\n\n(\n2\n\nS\n\n′\n\n\n+\n1\n)\n\n\n2\n(\n2\n\nS\n\nc\n\n\n+\n1\n)\n\n\n\n\n\n\nσ\n\nexch\n\n\n\n\n\n\nwhere σexch is the\n differential cross-section for electron exchange in elastic e−+H  collisions (e.g. Field 1958; Burke\n & Schey 1962). The derivation essentially follows Dalgarno & Rudge (1965), except that in our case the electron\n spin is coupled to the core electronic spin and not to the nuclear spin. We note that\n S′ =\n Sc ± 1\/2 and the factor\n (2S′ + 1) \/\n 2(2Sc + 1) is always in the range 0 to\n 1 and represents the probability that an electron exchange leads to a change in the\n total electronic spin of the Rydberg atom. In the limit p → 0, − f± →\n a±, where a± are the\n scattering lengths, which have values of a+ = 5.965 and a− = 1.769\n atomic units (Schwartz 1961). In this limit, for\n the case of Sc =\n 1\/2, via comparison of the expressions for the cross sections we\n find that \\begin{eqnarray} \\sigma_{nl,S=0 \\rightarrow n'l',S'=0} = 0.706 \\: \\sigma_{nl \\rightarrow n'l'}, \\\\ \\sigma_{nl,S=0 \\rightarrow n'l',S'=1} = 0.294 \\: \\sigma_{nl \\rightarrow n'l'}, \\\\ \\sigma_{nl,S=1 \\rightarrow n'l',S'=0} = 0.098 \\: \\sigma_{nl \\rightarrow n'l'}, \\\\ \\sigma_{nl,S=1 \\rightarrow n'l',S'=1} = 0.902 \\: \\sigma_{nl \\rightarrow n'l'}. \\end{eqnarray}\n\n\n\n\n\nσ\n\nnl,S\n=\n0\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n,\n\nS\n\n′\n\n\n=\n0\n\n\n=\n0.706\n\nσ\n\nnl\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n\n\n,\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nσ\n\nnl,S\n=\n0\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n,\n\nS\n\n′\n\n\n=\n1\n\n\n=\n0.294\n\nσ\n\nnl\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n\n\n,\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nσ\n\nnl,S\n=\n1\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n,\n\nS\n\n′\n\n\n=\n0\n\n\n=\n0.098\n\nσ\n\nnl\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n\n\n,\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nσ\n\nnl,S\n=\n1\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n,\n\nS\n\n′\n\n\n=\n1\n\n\n=\n0.902\n\nσ\n\nnl\n→\n\nn\n\n′\n\n\n\nl\n\n′\n\n\n\n\n.\n\n\n\n\n\n\n\n\n\n\n","Citation Text":["Dalgarno & Rudge (1965)"],"Citation Start End":[[1475,1498]]} {"Identifier":"2022ApJ...934...66S__Morishita_et_al._2019_Instance_1","Paragraph":"However, two recent pieces of evidence may suggest that standard disk accretion is not the only process at work in growing a BH to the (super)massive regime. The first is the discovery of an increasing number of active BHs with masses M\n• ≳ 109\nM\n⊙ at very high redshifts, z ≳ 7 (e.g., Mortlock et al. 2011; Wu et al. 2015; Venemans et al. 2017, 2018; Reed et al. 2019; Banados et al. 2018, 2021; Wang et al. 2019, 2021), when the age of the universe was shorter than 0.8 Gyr. The second is the robust measurements of extreme BH masses M\n• ≳109−10\nM\n⊙ at the center of early-type galaxies with stellar mass M\n⋆ ≳ 1011\nM\n⊙ (e.g., McConnell et al. 2011; Ferre-Mateu et al. 2015; Thomas et al. 2016; Mehrgan et al. 2019; Dullo et al. 2021) that formed most of their old stellar component during a star formation episode lasting some 108 yr at z ≳ 1, as demonstrated by astroarcheological measurements of their stellar ages and α-enhanced metal content (e.g., Thomas et al. 2005, 2010; Gallazzi et al. 2006, 2014; Johansson et al. 2012; Maiolino & Mannucci 2019; Morishita et al. 2019; Saracco et al.2020). These observations concur to raise the issue of how billion-solar-mass BHs may have grown in less than a gigayear. In fact, this is somewhat challenging if standard disk accretion starts from a light seed of ∼102\nM\n⊙ of stellar origin and proceeds with the typical Eddington ratios λ ≲ 1 as estimated out to z ∼ 6 in active BHs (see Vestergaard & Osmer 2009; Nobuta et al. 2012; Kelly & Shen 2013; Dai et al. 2014; Kim & Im 2019; Duras et al. 2020; Ananna et al. 2022), which would require an overall time ≳0.8\/λ Gyr to attain ∼109\nM\n⊙. Solutions may invoke mechanisms able to rapidly produce heavy BH seeds of 103−5\nM\n⊙, thus reducing the time required to attain the final masses by standard disk accretion (see Natarajan 2014, Mayer & Bonoli 2019, Inayoshi et al. 2020, and Volonteri et al. 2021 for recent and exhaustive reviews). Viable possibilities comprise direct collapse of gas clouds within a (proto)galaxy, possibly induced by galaxy mergers or enhanced matter inflow along cosmic filaments (e.g., Lodato & Natarajan 2007; Mayer et al. 2010, 2015; Di Matteo et al. 2012, 2017); merging of stars inside globular or nuclear star clusters (e.g., Portegies Zwart et al. 2004; Devecchi et al. 2012; Latif & Ferrara 2016; Kroupa et al. 2020); and migration of stellar BHs toward the nuclear galaxy regions via dynamical friction against the dense gas-rich environment in strongly star-forming progenitors of local massive galaxies (e.g., Boco et al. 2020, 2021).\n11\n\n\n11\nWhen referring to the dynamical friction mechanism, the term “seeds” is used in a broader sense with respect to the classic meaning in the literature. A seed is usually referred to as the first compact object on which subsequent disk accretion occurs, eventually leading to the formation of a supermassive BH. The heavy seeds formed with the dynamical friction mechanism are by-products of multiple mergers of already-existing stellar mass BHs (that in turn could be referred to as light seeds) forming across a wide redshift range.\n","Citation Text":["Morishita et al. 2019"],"Citation Start End":[[1059,1080]]} {"Identifier":"2022ApJ...929....8E__Zhang_et_al._2007_Instance_1","Paragraph":"In contrast to previous studies, the MFP expressions employed here are defined to include independent rigidity and nonlinear radial dependences. Furthermore, this approach does not make the simplifying assumption that λ\n⊥ is proportional to λ\n∥ (see, e.g., Ferreira et al. 2001). In order to study the radial and rigidity dependences of MFPs required to fit observations, as well as the values of these quantities at 1 au so as to compare these with theoretical predictions of the same, this study still implements simplified parametric expressions for these MFPs, motivated by the fact that the transport code here employed is written to perform on graphic processing units GPUs in CUDA, which allows for the vast performance increase required of such a study, but limits the number of definable variables due to memory constraints (see Dunzlaff et al. 2015, for additional information). Subsequently, λ\n∥ and λ\n⊥ are defined as\n5\n\n\n\nλ∥=λ∥,0PP0αrreβ,\n\n\n\n6\n\n\n\nλ⊥=λ⊥,0PP0γrreδ,\n\nwhere r\n\ne\n = 1 au, and P\n0 = 1 GV, in an approach similar to that employed by Engelbrecht & Di Felice (2020). Here, parameters α and β specify the respective rigidity and radial dependences of the parallel MFP, which assumes a value of λ\n0,∥ (in astronomical units) at Earth, with γ, δ, and λ\n0,⊥ playing the same roles with respect to the perpendicular MFP. In the parameter studies employed here, these quantities are varied over a broad range of values, chosen so as to include, as well as extend beyond, various theoretical predictions for these quantities. In terms of MFP values at 1 au, the ranges λ\n0,∥ ∈ [0.05, 1.0] au and λ\n0,⊥ ∈ [0.001, 0.5] au are chosen, so as to include values reported in previous such studies for the parallel MFP (e.g., Palmer 1982; Bieber et al. 1994; Dröge et al. 2014) as well as for the perpendicular MFP (e.g., Ferrando et al. 1993; Giacalone 1998; Burger et al. 2000; Zhang et al. 2007; Vogt et al. 2020), while taking into account various theoretical predictions and expressions previously used in modeling studies for these MFPs (e.g., Ferreira et al. 2003; Engelbrecht & Burger 2013b; Nndanganeni & Potgieter 2018; Engelbrecht 2019). For the rigidity dependences, it is assumed that α ∈ [−0.1, 0.67] and γ ∈ [−0.1, 0.33], incorporating the flat rigidity dependence expected of λ\n∥ for low-energy electrons (e.g., Dröge 1994; Potgieter 1996; Evenson 1998) within a range that includes dependences expected at higher rigidities as well as from different scattering theories (e.g., Dröge 2000; Teufel & Schlickeiser 2002; Shalchi & Schlickeiser 2004; Burger et al. 2008; Engelbrecht & Burger 2010). The range of rigidity dependences for λ\n⊥ was chosen following similar reasoning, with the aim of incorporating a flat rigidity dependence within a range that incorporates moderate rigidity dependences expected from various theories (e.g., Shalchi et al. 2004a; Gammon & Shalchi 2017; Dempers & Engelbrecht 2020) as well as prior particle transport studies (e.g., Zhang et al. 2007; Dröge & Kartavykh 2009) and numerical test particle simulations of diffusion coefficients (e.g., Minnie et al. 2007a; Dundovic et al. 2020). Lastly, radial dependences were varied such that β ∈ [0.5, 1.5] and δ ∈ [0.5, 1.5], taking into account various possible radial dependences for these MFPs reported by studies employing turbulence quantities yielded by various turbulence transport models as inputs for several theoretical expressions (see, e.g., Engelbrecht & Burger 2013b; Wiengarten et al. 2016; Chhiber et al. 2017; Zhao et al. 2017; Adhikari et al. 2021). In order to study the various dependencies in Equations (5) and (6), four initial electron energies are chosen, motivated by the fact that for these energies spacecraft data is available for periods of good and bad magnetic connection to the Jovian source as well as at the Jovian source itself. The three higher energies furthermore correspond to the three lowest-energy channels of the ISEE 3 data by Moses (1987). As the results of the parameter studies have to be compared to spectral fits (given by the dotted lines in Figure 1), this choice allows for the most transparent analysis of the deviation of the simulation results from in situ data. The six parameters governing the MFP expressions used in this study, along with the relevant initial energies, are\n7\n\n\n\nE=[0.0025,0.006,0.0085,0.0125]GeVλ∥,0=[0.05,0.106,0.224,0.473,1.0]auλ⊥,0=[0.001,0.00473,0.02236,0.1057,0.5]auα=[−0.1,−0.01,0.01,0.04,0.165,0.67]γ=[−0.1,−0.01,0.01,0.03,0.1,0.33]β=[0.5,0.658,0.866,1.397,1.5]δ=[0.5,0.658,0.866,1.397,1.5],\n\nwhich form a parameter space of consisting of 90,000 grid points, resulting in 180,000 simulations for comparison with observational points both well and badly connected to the Jovian source as shown in Figure 1.","Citation Text":["Zhang et al. 2007"],"Citation Start End":[[1889,1906]]} {"Identifier":"2022ApJ...929....8E__Zhang_et_al._2007_Instance_2","Paragraph":"In contrast to previous studies, the MFP expressions employed here are defined to include independent rigidity and nonlinear radial dependences. Furthermore, this approach does not make the simplifying assumption that λ\n⊥ is proportional to λ\n∥ (see, e.g., Ferreira et al. 2001). In order to study the radial and rigidity dependences of MFPs required to fit observations, as well as the values of these quantities at 1 au so as to compare these with theoretical predictions of the same, this study still implements simplified parametric expressions for these MFPs, motivated by the fact that the transport code here employed is written to perform on graphic processing units GPUs in CUDA, which allows for the vast performance increase required of such a study, but limits the number of definable variables due to memory constraints (see Dunzlaff et al. 2015, for additional information). Subsequently, λ\n∥ and λ\n⊥ are defined as\n5\n\n\n\nλ∥=λ∥,0PP0αrreβ,\n\n\n\n6\n\n\n\nλ⊥=λ⊥,0PP0γrreδ,\n\nwhere r\n\ne\n = 1 au, and P\n0 = 1 GV, in an approach similar to that employed by Engelbrecht & Di Felice (2020). Here, parameters α and β specify the respective rigidity and radial dependences of the parallel MFP, which assumes a value of λ\n0,∥ (in astronomical units) at Earth, with γ, δ, and λ\n0,⊥ playing the same roles with respect to the perpendicular MFP. In the parameter studies employed here, these quantities are varied over a broad range of values, chosen so as to include, as well as extend beyond, various theoretical predictions for these quantities. In terms of MFP values at 1 au, the ranges λ\n0,∥ ∈ [0.05, 1.0] au and λ\n0,⊥ ∈ [0.001, 0.5] au are chosen, so as to include values reported in previous such studies for the parallel MFP (e.g., Palmer 1982; Bieber et al. 1994; Dröge et al. 2014) as well as for the perpendicular MFP (e.g., Ferrando et al. 1993; Giacalone 1998; Burger et al. 2000; Zhang et al. 2007; Vogt et al. 2020), while taking into account various theoretical predictions and expressions previously used in modeling studies for these MFPs (e.g., Ferreira et al. 2003; Engelbrecht & Burger 2013b; Nndanganeni & Potgieter 2018; Engelbrecht 2019). For the rigidity dependences, it is assumed that α ∈ [−0.1, 0.67] and γ ∈ [−0.1, 0.33], incorporating the flat rigidity dependence expected of λ\n∥ for low-energy electrons (e.g., Dröge 1994; Potgieter 1996; Evenson 1998) within a range that includes dependences expected at higher rigidities as well as from different scattering theories (e.g., Dröge 2000; Teufel & Schlickeiser 2002; Shalchi & Schlickeiser 2004; Burger et al. 2008; Engelbrecht & Burger 2010). The range of rigidity dependences for λ\n⊥ was chosen following similar reasoning, with the aim of incorporating a flat rigidity dependence within a range that incorporates moderate rigidity dependences expected from various theories (e.g., Shalchi et al. 2004a; Gammon & Shalchi 2017; Dempers & Engelbrecht 2020) as well as prior particle transport studies (e.g., Zhang et al. 2007; Dröge & Kartavykh 2009) and numerical test particle simulations of diffusion coefficients (e.g., Minnie et al. 2007a; Dundovic et al. 2020). Lastly, radial dependences were varied such that β ∈ [0.5, 1.5] and δ ∈ [0.5, 1.5], taking into account various possible radial dependences for these MFPs reported by studies employing turbulence quantities yielded by various turbulence transport models as inputs for several theoretical expressions (see, e.g., Engelbrecht & Burger 2013b; Wiengarten et al. 2016; Chhiber et al. 2017; Zhao et al. 2017; Adhikari et al. 2021). In order to study the various dependencies in Equations (5) and (6), four initial electron energies are chosen, motivated by the fact that for these energies spacecraft data is available for periods of good and bad magnetic connection to the Jovian source as well as at the Jovian source itself. The three higher energies furthermore correspond to the three lowest-energy channels of the ISEE 3 data by Moses (1987). As the results of the parameter studies have to be compared to spectral fits (given by the dotted lines in Figure 1), this choice allows for the most transparent analysis of the deviation of the simulation results from in situ data. The six parameters governing the MFP expressions used in this study, along with the relevant initial energies, are\n7\n\n\n\nE=[0.0025,0.006,0.0085,0.0125]GeVλ∥,0=[0.05,0.106,0.224,0.473,1.0]auλ⊥,0=[0.001,0.00473,0.02236,0.1057,0.5]auα=[−0.1,−0.01,0.01,0.04,0.165,0.67]γ=[−0.1,−0.01,0.01,0.03,0.1,0.33]β=[0.5,0.658,0.866,1.397,1.5]δ=[0.5,0.658,0.866,1.397,1.5],\n\nwhich form a parameter space of consisting of 90,000 grid points, resulting in 180,000 simulations for comparison with observational points both well and badly connected to the Jovian source as shown in Figure 1.","Citation Text":["Zhang et al. 2007"],"Citation Start End":[[2984,3001]]} {"Identifier":"2022ApJ...929....8EFerreira_et_al._2001_Instance_1","Paragraph":"In contrast to previous studies, the MFP expressions employed here are defined to include independent rigidity and nonlinear radial dependences. Furthermore, this approach does not make the simplifying assumption that λ\n⊥ is proportional to λ\n∥ (see, e.g., Ferreira et al. 2001). In order to study the radial and rigidity dependences of MFPs required to fit observations, as well as the values of these quantities at 1 au so as to compare these with theoretical predictions of the same, this study still implements simplified parametric expressions for these MFPs, motivated by the fact that the transport code here employed is written to perform on graphic processing units GPUs in CUDA, which allows for the vast performance increase required of such a study, but limits the number of definable variables due to memory constraints (see Dunzlaff et al. 2015, for additional information). Subsequently, λ\n∥ and λ\n⊥ are defined as\n5\n\n\n\nλ∥=λ∥,0PP0αrreβ,\n\n\n\n6\n\n\n\nλ⊥=λ⊥,0PP0γrreδ,\n\nwhere r\n\ne\n = 1 au, and P\n0 = 1 GV, in an approach similar to that employed by Engelbrecht & Di Felice (2020). Here, parameters α and β specify the respective rigidity and radial dependences of the parallel MFP, which assumes a value of λ\n0,∥ (in astronomical units) at Earth, with γ, δ, and λ\n0,⊥ playing the same roles with respect to the perpendicular MFP. In the parameter studies employed here, these quantities are varied over a broad range of values, chosen so as to include, as well as extend beyond, various theoretical predictions for these quantities. In terms of MFP values at 1 au, the ranges λ\n0,∥ ∈ [0.05, 1.0] au and λ\n0,⊥ ∈ [0.001, 0.5] au are chosen, so as to include values reported in previous such studies for the parallel MFP (e.g., Palmer 1982; Bieber et al. 1994; Dröge et al. 2014) as well as for the perpendicular MFP (e.g., Ferrando et al. 1993; Giacalone 1998; Burger et al. 2000; Zhang et al. 2007; Vogt et al. 2020), while taking into account various theoretical predictions and expressions previously used in modeling studies for these MFPs (e.g., Ferreira et al. 2003; Engelbrecht & Burger 2013b; Nndanganeni & Potgieter 2018; Engelbrecht 2019). For the rigidity dependences, it is assumed that α ∈ [−0.1, 0.67] and γ ∈ [−0.1, 0.33], incorporating the flat rigidity dependence expected of λ\n∥ for low-energy electrons (e.g., Dröge 1994; Potgieter 1996; Evenson 1998) within a range that includes dependences expected at higher rigidities as well as from different scattering theories (e.g., Dröge 2000; Teufel & Schlickeiser 2002; Shalchi & Schlickeiser 2004; Burger et al. 2008; Engelbrecht & Burger 2010). The range of rigidity dependences for λ\n⊥ was chosen following similar reasoning, with the aim of incorporating a flat rigidity dependence within a range that incorporates moderate rigidity dependences expected from various theories (e.g., Shalchi et al. 2004a; Gammon & Shalchi 2017; Dempers & Engelbrecht 2020) as well as prior particle transport studies (e.g., Zhang et al. 2007; Dröge & Kartavykh 2009) and numerical test particle simulations of diffusion coefficients (e.g., Minnie et al. 2007a; Dundovic et al. 2020). Lastly, radial dependences were varied such that β ∈ [0.5, 1.5] and δ ∈ [0.5, 1.5], taking into account various possible radial dependences for these MFPs reported by studies employing turbulence quantities yielded by various turbulence transport models as inputs for several theoretical expressions (see, e.g., Engelbrecht & Burger 2013b; Wiengarten et al. 2016; Chhiber et al. 2017; Zhao et al. 2017; Adhikari et al. 2021). In order to study the various dependencies in Equations (5) and (6), four initial electron energies are chosen, motivated by the fact that for these energies spacecraft data is available for periods of good and bad magnetic connection to the Jovian source as well as at the Jovian source itself. The three higher energies furthermore correspond to the three lowest-energy channels of the ISEE 3 data by Moses (1987). As the results of the parameter studies have to be compared to spectral fits (given by the dotted lines in Figure 1), this choice allows for the most transparent analysis of the deviation of the simulation results from in situ data. The six parameters governing the MFP expressions used in this study, along with the relevant initial energies, are\n7\n\n\n\nE=[0.0025,0.006,0.0085,0.0125]GeVλ∥,0=[0.05,0.106,0.224,0.473,1.0]auλ⊥,0=[0.001,0.00473,0.02236,0.1057,0.5]auα=[−0.1,−0.01,0.01,0.04,0.165,0.67]γ=[−0.1,−0.01,0.01,0.03,0.1,0.33]β=[0.5,0.658,0.866,1.397,1.5]δ=[0.5,0.658,0.866,1.397,1.5],\n\nwhich form a parameter space of consisting of 90,000 grid points, resulting in 180,000 simulations for comparison with observational points both well and badly connected to the Jovian source as shown in Figure 1.","Citation Text":["Ferreira et al. 2001"],"Citation Start End":[[257,277]]} {"Identifier":"2022ApJ...929....8EDunzlaff_et_al._2015_Instance_1","Paragraph":"In contrast to previous studies, the MFP expressions employed here are defined to include independent rigidity and nonlinear radial dependences. Furthermore, this approach does not make the simplifying assumption that λ\n⊥ is proportional to λ\n∥ (see, e.g., Ferreira et al. 2001). In order to study the radial and rigidity dependences of MFPs required to fit observations, as well as the values of these quantities at 1 au so as to compare these with theoretical predictions of the same, this study still implements simplified parametric expressions for these MFPs, motivated by the fact that the transport code here employed is written to perform on graphic processing units GPUs in CUDA, which allows for the vast performance increase required of such a study, but limits the number of definable variables due to memory constraints (see Dunzlaff et al. 2015, for additional information). Subsequently, λ\n∥ and λ\n⊥ are defined as\n5\n\n\n\nλ∥=λ∥,0PP0αrreβ,\n\n\n\n6\n\n\n\nλ⊥=λ⊥,0PP0γrreδ,\n\nwhere r\n\ne\n = 1 au, and P\n0 = 1 GV, in an approach similar to that employed by Engelbrecht & Di Felice (2020). Here, parameters α and β specify the respective rigidity and radial dependences of the parallel MFP, which assumes a value of λ\n0,∥ (in astronomical units) at Earth, with γ, δ, and λ\n0,⊥ playing the same roles with respect to the perpendicular MFP. In the parameter studies employed here, these quantities are varied over a broad range of values, chosen so as to include, as well as extend beyond, various theoretical predictions for these quantities. In terms of MFP values at 1 au, the ranges λ\n0,∥ ∈ [0.05, 1.0] au and λ\n0,⊥ ∈ [0.001, 0.5] au are chosen, so as to include values reported in previous such studies for the parallel MFP (e.g., Palmer 1982; Bieber et al. 1994; Dröge et al. 2014) as well as for the perpendicular MFP (e.g., Ferrando et al. 1993; Giacalone 1998; Burger et al. 2000; Zhang et al. 2007; Vogt et al. 2020), while taking into account various theoretical predictions and expressions previously used in modeling studies for these MFPs (e.g., Ferreira et al. 2003; Engelbrecht & Burger 2013b; Nndanganeni & Potgieter 2018; Engelbrecht 2019). For the rigidity dependences, it is assumed that α ∈ [−0.1, 0.67] and γ ∈ [−0.1, 0.33], incorporating the flat rigidity dependence expected of λ\n∥ for low-energy electrons (e.g., Dröge 1994; Potgieter 1996; Evenson 1998) within a range that includes dependences expected at higher rigidities as well as from different scattering theories (e.g., Dröge 2000; Teufel & Schlickeiser 2002; Shalchi & Schlickeiser 2004; Burger et al. 2008; Engelbrecht & Burger 2010). The range of rigidity dependences for λ\n⊥ was chosen following similar reasoning, with the aim of incorporating a flat rigidity dependence within a range that incorporates moderate rigidity dependences expected from various theories (e.g., Shalchi et al. 2004a; Gammon & Shalchi 2017; Dempers & Engelbrecht 2020) as well as prior particle transport studies (e.g., Zhang et al. 2007; Dröge & Kartavykh 2009) and numerical test particle simulations of diffusion coefficients (e.g., Minnie et al. 2007a; Dundovic et al. 2020). Lastly, radial dependences were varied such that β ∈ [0.5, 1.5] and δ ∈ [0.5, 1.5], taking into account various possible radial dependences for these MFPs reported by studies employing turbulence quantities yielded by various turbulence transport models as inputs for several theoretical expressions (see, e.g., Engelbrecht & Burger 2013b; Wiengarten et al. 2016; Chhiber et al. 2017; Zhao et al. 2017; Adhikari et al. 2021). In order to study the various dependencies in Equations (5) and (6), four initial electron energies are chosen, motivated by the fact that for these energies spacecraft data is available for periods of good and bad magnetic connection to the Jovian source as well as at the Jovian source itself. The three higher energies furthermore correspond to the three lowest-energy channels of the ISEE 3 data by Moses (1987). As the results of the parameter studies have to be compared to spectral fits (given by the dotted lines in Figure 1), this choice allows for the most transparent analysis of the deviation of the simulation results from in situ data. The six parameters governing the MFP expressions used in this study, along with the relevant initial energies, are\n7\n\n\n\nE=[0.0025,0.006,0.0085,0.0125]GeVλ∥,0=[0.05,0.106,0.224,0.473,1.0]auλ⊥,0=[0.001,0.00473,0.02236,0.1057,0.5]auα=[−0.1,−0.01,0.01,0.04,0.165,0.67]γ=[−0.1,−0.01,0.01,0.03,0.1,0.33]β=[0.5,0.658,0.866,1.397,1.5]δ=[0.5,0.658,0.866,1.397,1.5],\n\nwhich form a parameter space of consisting of 90,000 grid points, resulting in 180,000 simulations for comparison with observational points both well and badly connected to the Jovian source as shown in Figure 1.","Citation Text":["Dunzlaff et al. 2015"],"Citation Start End":[[838,858]]} {"Identifier":"2022ApJ...929....8EWiengarten_et_al._2016_Instance_1","Paragraph":"In contrast to previous studies, the MFP expressions employed here are defined to include independent rigidity and nonlinear radial dependences. Furthermore, this approach does not make the simplifying assumption that λ\n⊥ is proportional to λ\n∥ (see, e.g., Ferreira et al. 2001). In order to study the radial and rigidity dependences of MFPs required to fit observations, as well as the values of these quantities at 1 au so as to compare these with theoretical predictions of the same, this study still implements simplified parametric expressions for these MFPs, motivated by the fact that the transport code here employed is written to perform on graphic processing units GPUs in CUDA, which allows for the vast performance increase required of such a study, but limits the number of definable variables due to memory constraints (see Dunzlaff et al. 2015, for additional information). Subsequently, λ\n∥ and λ\n⊥ are defined as\n5\n\n\n\nλ∥=λ∥,0PP0αrreβ,\n\n\n\n6\n\n\n\nλ⊥=λ⊥,0PP0γrreδ,\n\nwhere r\n\ne\n = 1 au, and P\n0 = 1 GV, in an approach similar to that employed by Engelbrecht & Di Felice (2020). Here, parameters α and β specify the respective rigidity and radial dependences of the parallel MFP, which assumes a value of λ\n0,∥ (in astronomical units) at Earth, with γ, δ, and λ\n0,⊥ playing the same roles with respect to the perpendicular MFP. In the parameter studies employed here, these quantities are varied over a broad range of values, chosen so as to include, as well as extend beyond, various theoretical predictions for these quantities. In terms of MFP values at 1 au, the ranges λ\n0,∥ ∈ [0.05, 1.0] au and λ\n0,⊥ ∈ [0.001, 0.5] au are chosen, so as to include values reported in previous such studies for the parallel MFP (e.g., Palmer 1982; Bieber et al. 1994; Dröge et al. 2014) as well as for the perpendicular MFP (e.g., Ferrando et al. 1993; Giacalone 1998; Burger et al. 2000; Zhang et al. 2007; Vogt et al. 2020), while taking into account various theoretical predictions and expressions previously used in modeling studies for these MFPs (e.g., Ferreira et al. 2003; Engelbrecht & Burger 2013b; Nndanganeni & Potgieter 2018; Engelbrecht 2019). For the rigidity dependences, it is assumed that α ∈ [−0.1, 0.67] and γ ∈ [−0.1, 0.33], incorporating the flat rigidity dependence expected of λ\n∥ for low-energy electrons (e.g., Dröge 1994; Potgieter 1996; Evenson 1998) within a range that includes dependences expected at higher rigidities as well as from different scattering theories (e.g., Dröge 2000; Teufel & Schlickeiser 2002; Shalchi & Schlickeiser 2004; Burger et al. 2008; Engelbrecht & Burger 2010). The range of rigidity dependences for λ\n⊥ was chosen following similar reasoning, with the aim of incorporating a flat rigidity dependence within a range that incorporates moderate rigidity dependences expected from various theories (e.g., Shalchi et al. 2004a; Gammon & Shalchi 2017; Dempers & Engelbrecht 2020) as well as prior particle transport studies (e.g., Zhang et al. 2007; Dröge & Kartavykh 2009) and numerical test particle simulations of diffusion coefficients (e.g., Minnie et al. 2007a; Dundovic et al. 2020). Lastly, radial dependences were varied such that β ∈ [0.5, 1.5] and δ ∈ [0.5, 1.5], taking into account various possible radial dependences for these MFPs reported by studies employing turbulence quantities yielded by various turbulence transport models as inputs for several theoretical expressions (see, e.g., Engelbrecht & Burger 2013b; Wiengarten et al. 2016; Chhiber et al. 2017; Zhao et al. 2017; Adhikari et al. 2021). In order to study the various dependencies in Equations (5) and (6), four initial electron energies are chosen, motivated by the fact that for these energies spacecraft data is available for periods of good and bad magnetic connection to the Jovian source as well as at the Jovian source itself. The three higher energies furthermore correspond to the three lowest-energy channels of the ISEE 3 data by Moses (1987). As the results of the parameter studies have to be compared to spectral fits (given by the dotted lines in Figure 1), this choice allows for the most transparent analysis of the deviation of the simulation results from in situ data. The six parameters governing the MFP expressions used in this study, along with the relevant initial energies, are\n7\n\n\n\nE=[0.0025,0.006,0.0085,0.0125]GeVλ∥,0=[0.05,0.106,0.224,0.473,1.0]auλ⊥,0=[0.001,0.00473,0.02236,0.1057,0.5]auα=[−0.1,−0.01,0.01,0.04,0.165,0.67]γ=[−0.1,−0.01,0.01,0.03,0.1,0.33]β=[0.5,0.658,0.866,1.397,1.5]δ=[0.5,0.658,0.866,1.397,1.5],\n\nwhich form a parameter space of consisting of 90,000 grid points, resulting in 180,000 simulations for comparison with observational points both well and badly connected to the Jovian source as shown in Figure 1.","Citation Text":["Wiengarten et al. 2016"],"Citation Start End":[[3484,3506]]} {"Identifier":"2019MNRAS.482..240K__Scheuer_&_Feiler_1996_Instance_1","Paragraph":"Torques caused by a misalignment between the spin axis of a black hole and the angular momentum of the accretion disc can also induce jet precession. In an overall misaligned system the inner part of the accretion disc is aligned with the black hole spin axis by the combined effect of Lense–Thirring precession and internal viscosity of the disc. This process is known as the Bardeen–Petterson effect (Bardeen & Petterson 1975). The outer disc will maintain its angular momentum direction. Through the accretion of material of the outer disc on to the black hole, the black hole spin axis will precess and align with the outer disc. The precession time-scale is of the same order as the alignment time-scale (Scheuer & Feiler 1996). Two aspects of the disc-induced precession, namely the relatively slow precession rate and the single possible precession cycle in the alignment lifetime (Scheuer & Feiler 1996; Lodato & Pringle 2006), make this process less likely to be a cause of jet precession for the given radio sources. For example, following Lodato & Pringle (2006), adopting their numerical values for accretion efficiency ε and disc viscosity parameters α1, 2 and assuming black hole spin a ≈ 1, we obtain a precession period of\n(3)\r\n\\begin{eqnarray*}\r\n\\begin{split} t_\\mathrm{prec} &\\approx t_\\mathrm{align} \\approx 7\\, \\, \\mathrm{Myr} \\\\\r\n&\\times \\, a^{11\/16} \\left(\\frac{\\epsilon }{0.1}\\right)^{7\/8} \\left(\\frac{L}{0.1 L_\\mathrm{Edd}}\\right)^{-7\/8} M_9^{-1\/16} \\\\\r\n&\\times \\left(\\frac{\\alpha _1}{0.03}\\right)^{15\/16} \\left(\\frac{\\alpha _2}{0.3}\\right)^{-11\/16} \\, .\\\\\r\n\\end{split}\r\n\\end{eqnarray*}\r\nThis is larger than the precession period we estimated for Cygnus A. Simulations show that if the precession time-scale becomes comparable to the source age, very asymmetric lobe morphologies result (Donohoe & Smith 2016). As discussed in Section 3.3, the sources in our sample do not show such asymmetries, but often show smooth, ring-like hotspot features that suggest a local impact time-scale short compared to the source ages and thus many precession cycles. This is not consistent with precession induced by a misaligned accretion disc. A process that produces one precession cycle only, where the period of the cycle can be much shorter than the source age (equation 3), would have only a limited probability to be detected at the time a given source is observed. However, we also find precession frequently in comparatively old sources, e.g. 3C 33.1, 3C 303, and 3C 436. These are three of the seven sources with modelled ages of log(age\/yr) ≥ 7.9. This makes disc-induced precession less likely for this subpopulation.","Citation Text":["Scheuer & Feiler 1996"],"Citation Start End":[[710,731]]} {"Identifier":"2019MNRAS.482..240K__Scheuer_&_Feiler_1996_Instance_2","Paragraph":"Torques caused by a misalignment between the spin axis of a black hole and the angular momentum of the accretion disc can also induce jet precession. In an overall misaligned system the inner part of the accretion disc is aligned with the black hole spin axis by the combined effect of Lense–Thirring precession and internal viscosity of the disc. This process is known as the Bardeen–Petterson effect (Bardeen & Petterson 1975). The outer disc will maintain its angular momentum direction. Through the accretion of material of the outer disc on to the black hole, the black hole spin axis will precess and align with the outer disc. The precession time-scale is of the same order as the alignment time-scale (Scheuer & Feiler 1996). Two aspects of the disc-induced precession, namely the relatively slow precession rate and the single possible precession cycle in the alignment lifetime (Scheuer & Feiler 1996; Lodato & Pringle 2006), make this process less likely to be a cause of jet precession for the given radio sources. For example, following Lodato & Pringle (2006), adopting their numerical values for accretion efficiency ε and disc viscosity parameters α1, 2 and assuming black hole spin a ≈ 1, we obtain a precession period of\n(3)\r\n\\begin{eqnarray*}\r\n\\begin{split} t_\\mathrm{prec} &\\approx t_\\mathrm{align} \\approx 7\\, \\, \\mathrm{Myr} \\\\\r\n&\\times \\, a^{11\/16} \\left(\\frac{\\epsilon }{0.1}\\right)^{7\/8} \\left(\\frac{L}{0.1 L_\\mathrm{Edd}}\\right)^{-7\/8} M_9^{-1\/16} \\\\\r\n&\\times \\left(\\frac{\\alpha _1}{0.03}\\right)^{15\/16} \\left(\\frac{\\alpha _2}{0.3}\\right)^{-11\/16} \\, .\\\\\r\n\\end{split}\r\n\\end{eqnarray*}\r\nThis is larger than the precession period we estimated for Cygnus A. Simulations show that if the precession time-scale becomes comparable to the source age, very asymmetric lobe morphologies result (Donohoe & Smith 2016). As discussed in Section 3.3, the sources in our sample do not show such asymmetries, but often show smooth, ring-like hotspot features that suggest a local impact time-scale short compared to the source ages and thus many precession cycles. This is not consistent with precession induced by a misaligned accretion disc. A process that produces one precession cycle only, where the period of the cycle can be much shorter than the source age (equation 3), would have only a limited probability to be detected at the time a given source is observed. However, we also find precession frequently in comparatively old sources, e.g. 3C 33.1, 3C 303, and 3C 436. These are three of the seven sources with modelled ages of log(age\/yr) ≥ 7.9. This makes disc-induced precession less likely for this subpopulation.","Citation Text":["Scheuer & Feiler 1996"],"Citation Start End":[[889,910]]} {"Identifier":"2019MNRAS.482..240KDonohoe_&_Smith_2016_Instance_1","Paragraph":"Torques caused by a misalignment between the spin axis of a black hole and the angular momentum of the accretion disc can also induce jet precession. In an overall misaligned system the inner part of the accretion disc is aligned with the black hole spin axis by the combined effect of Lense–Thirring precession and internal viscosity of the disc. This process is known as the Bardeen–Petterson effect (Bardeen & Petterson 1975). The outer disc will maintain its angular momentum direction. Through the accretion of material of the outer disc on to the black hole, the black hole spin axis will precess and align with the outer disc. The precession time-scale is of the same order as the alignment time-scale (Scheuer & Feiler 1996). Two aspects of the disc-induced precession, namely the relatively slow precession rate and the single possible precession cycle in the alignment lifetime (Scheuer & Feiler 1996; Lodato & Pringle 2006), make this process less likely to be a cause of jet precession for the given radio sources. For example, following Lodato & Pringle (2006), adopting their numerical values for accretion efficiency ε and disc viscosity parameters α1, 2 and assuming black hole spin a ≈ 1, we obtain a precession period of\n(3)\r\n\\begin{eqnarray*}\r\n\\begin{split} t_\\mathrm{prec} &\\approx t_\\mathrm{align} \\approx 7\\, \\, \\mathrm{Myr} \\\\\r\n&\\times \\, a^{11\/16} \\left(\\frac{\\epsilon }{0.1}\\right)^{7\/8} \\left(\\frac{L}{0.1 L_\\mathrm{Edd}}\\right)^{-7\/8} M_9^{-1\/16} \\\\\r\n&\\times \\left(\\frac{\\alpha _1}{0.03}\\right)^{15\/16} \\left(\\frac{\\alpha _2}{0.3}\\right)^{-11\/16} \\, .\\\\\r\n\\end{split}\r\n\\end{eqnarray*}\r\nThis is larger than the precession period we estimated for Cygnus A. Simulations show that if the precession time-scale becomes comparable to the source age, very asymmetric lobe morphologies result (Donohoe & Smith 2016). As discussed in Section 3.3, the sources in our sample do not show such asymmetries, but often show smooth, ring-like hotspot features that suggest a local impact time-scale short compared to the source ages and thus many precession cycles. This is not consistent with precession induced by a misaligned accretion disc. A process that produces one precession cycle only, where the period of the cycle can be much shorter than the source age (equation 3), would have only a limited probability to be detected at the time a given source is observed. However, we also find precession frequently in comparatively old sources, e.g. 3C 33.1, 3C 303, and 3C 436. These are three of the seven sources with modelled ages of log(age\/yr) ≥ 7.9. This makes disc-induced precession less likely for this subpopulation.","Citation Text":["Donohoe & Smith 2016"],"Citation Start End":[[1824,1844]]} {"Identifier":"2016MNRAS.460.2979V__Bernardi_et_al._2003_Instance_1","Paragraph":"We end by studying the BH mass versus stellar velocity dispersion, σ, in Fig. 7. This is also a benchmark scaling, and it is considered to be one of the best predictors for BH masses, i.e. to have a small intrinsic scatter (0.3 dex). This is perhaps the most problematic for Horizon-AGN. If we fit a single logarithmic slope to the BH mass versus stellar velocity dispersion, we find a value of 4.02 for galaxies with σ > 60 km s−1, compared to 4.38 found by Kormendy & Ho on a culled subsample of the galaxies shown in Fig. 7. The main reason is that velocity dispersions in the simulation are underestimated at Mbulge 1011 M⊙ (σ 200 km s−1), and overestimated above, when comparing to the observed Faber–Jackson relation (Bernardi et al. 2003). The dearth of BHs with MBH 5 × 107  M⊙ in intermediate-mass galaxies highlighted in the discussion of Fig. 5 also contributes, but given the good agreement in the MBH versus Mbulge relation, it is a minor contribution, for this specific comparison. One contribution to the discrepancy is that galaxy sizes in the simulation are larger than for observed galaxies with mass ≲ 1011 M⊙. In fact, the galaxy sizes are in good agreement with observed low-mass late-type galaxies, but are larger, by a factor of ∼ 3–4, than observed low-mass early-type galaxies (Dubois et al., in preparation). Since the complete sample is a mix of late- and early-type galaxies, there appears to be an overall mismatch at σ 200 km s−1 of a factor of ${\\sim } \\sqrt{2}$ in the velocity dispersion (roughly corresponding to an average overestimate of the galaxy size of a factor of 2). The velocity dispersion is also sensitive to the DM halo central profile, which depends not only on DM halo mass but also on a subtle interplay with the baryons and AGN feedback. Indeed, the central DM densities in Horizon-AGN are lower than for the Horizon-noAGN simulation, which differs only in that AGN are not included in the latter. We defer a more detailed study quantifying the exact contribution of this effect as a function of galaxy mass and assembly history to another paper (Peirani et al., in preparation).","Citation Text":["Bernardi et al. 2003"],"Citation Start End":[[726,746]]} {"Identifier":"2016MNRAS.460.2979VPeirani_et_al.,_in_preparation_Instance_1","Paragraph":"We end by studying the BH mass versus stellar velocity dispersion, σ, in Fig. 7. This is also a benchmark scaling, and it is considered to be one of the best predictors for BH masses, i.e. to have a small intrinsic scatter (0.3 dex). This is perhaps the most problematic for Horizon-AGN. If we fit a single logarithmic slope to the BH mass versus stellar velocity dispersion, we find a value of 4.02 for galaxies with σ > 60 km s−1, compared to 4.38 found by Kormendy & Ho on a culled subsample of the galaxies shown in Fig. 7. The main reason is that velocity dispersions in the simulation are underestimated at Mbulge 1011 M⊙ (σ 200 km s−1), and overestimated above, when comparing to the observed Faber–Jackson relation (Bernardi et al. 2003). The dearth of BHs with MBH 5 × 107  M⊙ in intermediate-mass galaxies highlighted in the discussion of Fig. 5 also contributes, but given the good agreement in the MBH versus Mbulge relation, it is a minor contribution, for this specific comparison. One contribution to the discrepancy is that galaxy sizes in the simulation are larger than for observed galaxies with mass ≲ 1011 M⊙. In fact, the galaxy sizes are in good agreement with observed low-mass late-type galaxies, but are larger, by a factor of ∼ 3–4, than observed low-mass early-type galaxies (Dubois et al., in preparation). Since the complete sample is a mix of late- and early-type galaxies, there appears to be an overall mismatch at σ 200 km s−1 of a factor of ${\\sim } \\sqrt{2}$ in the velocity dispersion (roughly corresponding to an average overestimate of the galaxy size of a factor of 2). The velocity dispersion is also sensitive to the DM halo central profile, which depends not only on DM halo mass but also on a subtle interplay with the baryons and AGN feedback. Indeed, the central DM densities in Horizon-AGN are lower than for the Horizon-noAGN simulation, which differs only in that AGN are not included in the latter. We defer a more detailed study quantifying the exact contribution of this effect as a function of galaxy mass and assembly history to another paper (Peirani et al., in preparation).","Citation Text":["Peirani et al., in preparation"],"Citation Start End":[[2101,2131]]} {"Identifier":"2016MNRAS.460.2979VDubois_et_al.,_in_preparation_Instance_1","Paragraph":"We end by studying the BH mass versus stellar velocity dispersion, σ, in Fig. 7. This is also a benchmark scaling, and it is considered to be one of the best predictors for BH masses, i.e. to have a small intrinsic scatter (0.3 dex). This is perhaps the most problematic for Horizon-AGN. If we fit a single logarithmic slope to the BH mass versus stellar velocity dispersion, we find a value of 4.02 for galaxies with σ > 60 km s−1, compared to 4.38 found by Kormendy & Ho on a culled subsample of the galaxies shown in Fig. 7. The main reason is that velocity dispersions in the simulation are underestimated at Mbulge 1011 M⊙ (σ 200 km s−1), and overestimated above, when comparing to the observed Faber–Jackson relation (Bernardi et al. 2003). The dearth of BHs with MBH 5 × 107  M⊙ in intermediate-mass galaxies highlighted in the discussion of Fig. 5 also contributes, but given the good agreement in the MBH versus Mbulge relation, it is a minor contribution, for this specific comparison. One contribution to the discrepancy is that galaxy sizes in the simulation are larger than for observed galaxies with mass ≲ 1011 M⊙. In fact, the galaxy sizes are in good agreement with observed low-mass late-type galaxies, but are larger, by a factor of ∼ 3–4, than observed low-mass early-type galaxies (Dubois et al., in preparation). Since the complete sample is a mix of late- and early-type galaxies, there appears to be an overall mismatch at σ 200 km s−1 of a factor of ${\\sim } \\sqrt{2}$ in the velocity dispersion (roughly corresponding to an average overestimate of the galaxy size of a factor of 2). The velocity dispersion is also sensitive to the DM halo central profile, which depends not only on DM halo mass but also on a subtle interplay with the baryons and AGN feedback. Indeed, the central DM densities in Horizon-AGN are lower than for the Horizon-noAGN simulation, which differs only in that AGN are not included in the latter. We defer a more detailed study quantifying the exact contribution of this effect as a function of galaxy mass and assembly history to another paper (Peirani et al., in preparation).","Citation Text":["Dubois et al., in preparation"],"Citation Start End":[[1306,1335]]} {"Identifier":"2020ApJ...892...68N__Läsker_et_al._2016_Instance_1","Paragraph":"However, our understanding of the scaling relations in lower-mass galaxies is lacking. This includes galaxies near the break of the galaxy stellar-mass function \n\n\n\n\n\n (e.g., Baldry et al. 2012) like the Milky Way (MW), as well as galaxies at lower masses. Measurements of black hole (BH18\n\n18\nIn this article, we use the abbreviations SMBH and BH interchangeably.\n) masses are lacking in these galaxies. Despite the MW’s precisely measured central BH mass of \n\n\n\n\n\n \n\n\n\n\n\n (Boehle et al. 2016; Gillessen et al. 2017), we actually know very little about the demographics of BHs in galaxies of this mass. In particular, there are only 11 published \n\n\n\n\n\n in spiral galaxies within ∼1 dex in stellar mass of the MW, but there are strong indications that the relations between \n\n\n\n\n\n and galaxy properties that hold at higher mass (Kormendy & Ho 2013; McConnell et al. 2013; Saglia et al. 2016; van den Bosch et al. 2016) break down for M⋆ spiral galaxies (Greene et al. 2010, 2016; Läsker et al. 2016). For instance, Andromeda is only ≲2 times more massive than the MW, but its SMBH is two orders of magnitude higher, \n\n\n\n\n\n ∼1.4 × 108M⊙ (Bender et al. 2005). At even lower galaxy masses, the changes in the inferred \n\n\n\n\n\n are twofold: not only does the scatter increase enormously at low mass (e.g., Reines et al. 2013), but it also seems that the \n\n\n\n\n\n are lower at fixed stellar mass or σ of the lower-mass systems (e.g., Kormendy & Ho 2013; Scott et al. 2013; Greene et al. 2016; Saglia et al. 2016; Nguyen et al. 2017, 2018, 2019, hereafter N17, N18, N19). Despite the incomplete sample of \n\n\n\n\n\n at lower masses, there are already two intriguing findings from the limited data available: (1) a factor of 2 difference in normalization seen in the \n\n\n\n\n\n–σ correlations for early-type (ETGs) and late-type (LTGs) galaxies (McConnell et al. 2013) and (2) a large scatter up to two orders of magnitude of MBH seen around the global scaling relations for low-mass systems (Greene et al. 2010; Scott et al. 2013; Graham & Scott 2015; Greene et al. 2016; Läsker et al. 2016; Chilingarian et al. 2018).","Citation Text":["Läsker et al. 2016"],"Citation Start End":[[980,998]]} {"Identifier":"2020ApJ...892...68N__Läsker_et_al._2016_Instance_2","Paragraph":"However, our understanding of the scaling relations in lower-mass galaxies is lacking. This includes galaxies near the break of the galaxy stellar-mass function \n\n\n\n\n\n (e.g., Baldry et al. 2012) like the Milky Way (MW), as well as galaxies at lower masses. Measurements of black hole (BH18\n\n18\nIn this article, we use the abbreviations SMBH and BH interchangeably.\n) masses are lacking in these galaxies. Despite the MW’s precisely measured central BH mass of \n\n\n\n\n\n \n\n\n\n\n\n (Boehle et al. 2016; Gillessen et al. 2017), we actually know very little about the demographics of BHs in galaxies of this mass. In particular, there are only 11 published \n\n\n\n\n\n in spiral galaxies within ∼1 dex in stellar mass of the MW, but there are strong indications that the relations between \n\n\n\n\n\n and galaxy properties that hold at higher mass (Kormendy & Ho 2013; McConnell et al. 2013; Saglia et al. 2016; van den Bosch et al. 2016) break down for M⋆ spiral galaxies (Greene et al. 2010, 2016; Läsker et al. 2016). For instance, Andromeda is only ≲2 times more massive than the MW, but its SMBH is two orders of magnitude higher, \n\n\n\n\n\n ∼1.4 × 108M⊙ (Bender et al. 2005). At even lower galaxy masses, the changes in the inferred \n\n\n\n\n\n are twofold: not only does the scatter increase enormously at low mass (e.g., Reines et al. 2013), but it also seems that the \n\n\n\n\n\n are lower at fixed stellar mass or σ of the lower-mass systems (e.g., Kormendy & Ho 2013; Scott et al. 2013; Greene et al. 2016; Saglia et al. 2016; Nguyen et al. 2017, 2018, 2019, hereafter N17, N18, N19). Despite the incomplete sample of \n\n\n\n\n\n at lower masses, there are already two intriguing findings from the limited data available: (1) a factor of 2 difference in normalization seen in the \n\n\n\n\n\n–σ correlations for early-type (ETGs) and late-type (LTGs) galaxies (McConnell et al. 2013) and (2) a large scatter up to two orders of magnitude of MBH seen around the global scaling relations for low-mass systems (Greene et al. 2010; Scott et al. 2013; Graham & Scott 2015; Greene et al. 2016; Läsker et al. 2016; Chilingarian et al. 2018).","Citation Text":["Läsker et al. 2016"],"Citation Start End":[[2054,2072]]} {"Identifier":"2019MNRAS.487.5564L__Mao_et_al._2013_Instance_1","Paragraph":"The 21-cm line is the transition line of atomic hydrogen between two hyperfine states that are split from the ground state due to the spin coupling of the nucleus and electron. The 21-cm brightness temperature from a bulk of hydrogen gas depends on the matter density, the neutral fraction, the velocity gradient, and the spin temperature. During the EoR, it is reasonable to assume that X-ray heating and Ly α-pumping effects are so efficient that the H i spin temperature is much greater than the CMB temperature. In this limit, the power spectrum of 21-cm brightness temperature fluctuations can be written as (Datta et al. 2012; Mao et al. 2013)\n(3)\r\n\\begin{eqnarray*}\r\nP_{\\Delta T}({\\boldsymbol k},{\\boldsymbol n},z) = \\widetilde{\\delta T}_b^2 \\bar{x}_{\\rm H\\,{\\small I}}^2\\, \\left[ b_{\\rho _{\\rm H\\,{\\small I}}}(z) + \\mu _{\\boldsymbol k}^2 \\right]^2\\, P_{\\zeta }(k,{\\boldsymbol n},z),\r\n\\end{eqnarray*}\r\nat large scales, with\n(4)\r\n\\begin{eqnarray*}\r\n\\widetilde{\\delta T}_b(z) = (23.88\\, {\\rm mK}) (\\frac{\\Omega _b h^2}{0.02}) \\sqrt{\\frac{0.15}{\\Omega _M h^2} \\frac{1+z}{10}}.\r\n\\end{eqnarray*}\r\nNote that $\\bar{x}_{\\rm H\\,{\\small I}}$ is the global neutral fraction that implicitly depends on the redshift, and μk ≡ k · n\/|k| (cosine of angle between line of sight n and wave vector k of a given Fourier mode). We can relate the neutral hydrogen density fluctuations to the total matter density fluctuations with a simple bias parameter, the neutral density bias, $b_{\\rho _{\\rm H\\,{\\small I}}}(k,z) \\equiv \\tilde{\\delta }_{\\rho _{\\rm H\\,{\\small I}}}({\\boldsymbol k},z)\/\\tilde{\\delta }_{\\rho }({\\boldsymbol k},z)$. At large scales, the bias approaches to a scale-independent value, $b_{\\rho _{\\rm H\\,{\\small I}}}(z)$. Here, we assume that the baryonic distribution traces the cold dark matter distribution at large scales, so $\\delta _{\\rho _{\\rm H}} = \\delta _{\\rho }$. Also, we assume that no additional hemispherical power asymmetry was generated during the evolution of the Universe, so the dipolar modulation of the curvature perturbation is transferred to the 21-cm power spectrum with the same form.","Citation Text":["Mao et al. 2013"],"Citation Start End":[[633,648]]} {"Identifier":"2020MNRAS.491.1656A__Dutton_et_al._2019_Instance_2","Paragraph":"The sensitivity of dwarfs to galaxy formation physics, like the gas density at which stars form (e.g. Kravtsov 2003; Saitoh et al. 2008) or the details of galactic outflows (e.g. Read et al. 2006b), makes them a natural ‘rosetta stone’ for constraining galaxy formation models. Early work simulating dwarf galaxies focused on high resolution small box simulations, stopping at high redshift (z ∼ 5–10) to avoid gravitational collapse on the scale of the box (e.g. Abel et al. 1998; Gnedin & Kravtsov 2006; Read et al. 2006b; Mashchenko, Wadsley & Couchman 2008). These simulations demonstrated that stellar winds, SN feedback, and ionizing radiation combine to prevent star formation in halo masses below ∼107–8 M⊙ (Read et al. 2006b; Bland-Hawthorn, Sutherland & Webster 2015). Furthermore, once cooling below 104 K is permitted and gas is allowed to reach high densities $n_{\\rm max} {\\gtrsim}10\\,{\\rm cm}^{-3}$ (requiring a spatial and mass resolution better than $\\Delta x {\\lesssim}100$ pc and mmin 103 M⊙; Pontzen & Governato 2012; Benitez-Llambay et al. 2019; Bose et al. 2019; Dutton et al. 2019), star formation becomes much more stochastic and violent (Mashchenko et al. 2008; Pontzen & Governato 2012; Dutton et al. 2019). The repeated action of gas cooling and blow-out due to feedback expels DM from the galaxy centre, transforming an initially dense DM cusp to a core (e.g. Read & Gilmore 2005; Pontzen & Governato 2012). Finally, independent of any internal sources of feedback energy, cosmic reionization can halt star formation in low-mass galaxies (e.g. Gnedin & Kravtsov 2006). Dwarfs that have not reached a mass of $M_{200} {\\gtrsim}10^8$ M⊙ (see Section 2.4 for a definition of M200) by the redshift that reionization begins (z ∼ 8–10; Gnedin & Kaurov 2014; Ocvirk et al. 2018) are gradually starved of fresh cold gas, causing their star formation to shut down by a redshift of z ∼ 4 (Oñorbe et al. 2015). This is similar to the age of nearby ‘ultra-faint’ dwarf galaxies (UFDs) that have $M_* {\\lesssim}10^5$ M⊙, suggesting that at least some of these are likely to be relics from reionization, inhabiting pre-infall halo masses in the range M200 ∼ 108–9 M⊙ (Gnedin & Kravtsov 2006; Bovill & Ricotti 2009, 2011; Brown et al. 2014; Weisz et al. 2014; Jethwa, Erkal & Belokurov 2018; Read & Erkal 2019).","Citation Text":["Dutton et al. 2019"],"Citation Start End":[[1214,1232]]} {"Identifier":"2020MNRAS.491.1656A__Dutton_et_al._2019_Instance_1","Paragraph":"The sensitivity of dwarfs to galaxy formation physics, like the gas density at which stars form (e.g. Kravtsov 2003; Saitoh et al. 2008) or the details of galactic outflows (e.g. Read et al. 2006b), makes them a natural ‘rosetta stone’ for constraining galaxy formation models. Early work simulating dwarf galaxies focused on high resolution small box simulations, stopping at high redshift (z ∼ 5–10) to avoid gravitational collapse on the scale of the box (e.g. Abel et al. 1998; Gnedin & Kravtsov 2006; Read et al. 2006b; Mashchenko, Wadsley & Couchman 2008). These simulations demonstrated that stellar winds, SN feedback, and ionizing radiation combine to prevent star formation in halo masses below ∼107–8 M⊙ (Read et al. 2006b; Bland-Hawthorn, Sutherland & Webster 2015). Furthermore, once cooling below 104 K is permitted and gas is allowed to reach high densities $n_{\\rm max} {\\gtrsim}10\\,{\\rm cm}^{-3}$ (requiring a spatial and mass resolution better than $\\Delta x {\\lesssim}100$ pc and mmin 103 M⊙; Pontzen & Governato 2012; Benitez-Llambay et al. 2019; Bose et al. 2019; Dutton et al. 2019), star formation becomes much more stochastic and violent (Mashchenko et al. 2008; Pontzen & Governato 2012; Dutton et al. 2019). The repeated action of gas cooling and blow-out due to feedback expels DM from the galaxy centre, transforming an initially dense DM cusp to a core (e.g. Read & Gilmore 2005; Pontzen & Governato 2012). Finally, independent of any internal sources of feedback energy, cosmic reionization can halt star formation in low-mass galaxies (e.g. Gnedin & Kravtsov 2006). Dwarfs that have not reached a mass of $M_{200} {\\gtrsim}10^8$ M⊙ (see Section 2.4 for a definition of M200) by the redshift that reionization begins (z ∼ 8–10; Gnedin & Kaurov 2014; Ocvirk et al. 2018) are gradually starved of fresh cold gas, causing their star formation to shut down by a redshift of z ∼ 4 (Oñorbe et al. 2015). This is similar to the age of nearby ‘ultra-faint’ dwarf galaxies (UFDs) that have $M_* {\\lesssim}10^5$ M⊙, suggesting that at least some of these are likely to be relics from reionization, inhabiting pre-infall halo masses in the range M200 ∼ 108–9 M⊙ (Gnedin & Kravtsov 2006; Bovill & Ricotti 2009, 2011; Brown et al. 2014; Weisz et al. 2014; Jethwa, Erkal & Belokurov 2018; Read & Erkal 2019).","Citation Text":["Dutton et al. 2019"],"Citation Start End":[[1086,1104]]} {"Identifier":"2018AandA...609A.131G__Vries_et_al._1987_Instance_1","Paragraph":"Moreover, there could also be some contribution to the detected temperature asymmetry from high-latitude gas clouds in our Galaxy along the line of sight toward M 81. In this respect we note that M 81 is at about 40.9° north of the Galactic disk, where contamination from the Milky Way is expected to be low. However, interpretation of astronomical observations is often hampered by the lack of direct distance information. Indeed, it is often not easy to judge whether objects on the same line of sight are physically related or not. Since the discovery of the Arp’s Loop (Arp 1965) the nature of the interstellar clouds in this region has been debated; in particular whether they are related to the tidal arms around the galaxy triplet (Sun et al. 2005; de Mello et al. 2008) or to Galactic foreground cirrus (Sollima et al. 2010; Davies et al. 2010). Already Sandage et al. (1976) presented evidence showing that we are observing the M 81 triplet through widespread Galactic foreground cirrus clouds and de Vries et al. 1987 built large-scale HI, CO, and dust maps that showed Galactic cirrus emission toward the M 81 region with NH ≃ 1−2 × 1020 cm-2. The technique used to distinguish between the emission from extragalactic or Galactic gas and dust relies on spectral measurements and on the identification of the line of sight velocities, which are expected to be different in each case. Unfortunately, in the case of the M 81 Group, this technique appears hardly applicable since the radial velocities of extragalactic and Galactic clouds share a similar LSR (local standard of rest) velocity range (Heithausen 2012). Several small-area molecular clouds (SAMS), that is, tiny molecular clouds in a region where the shielding of the interstellar radiation field is too low (so that these clouds cannot survive for a long time), have been detected by Heithausen (2002) toward the M 81 Group. More recently, data from the Spectral and Photometric Imaging Receiver (SPIRE) instrument onboard Herschel ESA space observatory and Multiband Imaging Photometer for Spitzer (MIPS) onboard Spitzer allowed the identification of several dust clouds north of the M 81 galaxy with a total hydrogen column density in the range 1.5–5 × 1020 cm-2 and dust temperatures between 13 and 17 K (Heithausen 2012). However, since there is no obvious difference among the individual clouds, there was no way to distinguish between Galactic or extragalactic origin although it is likely that some of the IR emission both toward M 81 and NGC 3077 is of Galactic origin. Temperature asymmetry studies in Planck data may be indicative of the bulk dynamics in the observed region provided that other Local (Galactic) contamination in the data is identified and subtracted. This is not always possible, as in the case of the M 81 Group, and therefore it would be important to identify and study other examples of dust clouds where their origin, either Galactic or extragalactic, is not clear. One such example might be provided by the interacting system toward NGC 4435\/4438 (Cortese et al. 2010) where the SAMS found appear more consistent with Galactic cirrus clouds than with extragalactic molecular complexes. Incidentally, the region A1 within R0.50 has been studied by Barker et al. (2009), who found evidence for the presence of an extended structural component beyond the M 81 optical disk, with a much flatter surface brightness profile, which might contain ≃10–15% of the M 81 total V-band luminosity. However, the lack of both a similar analysis in the other quadrants (and at larger distances from the M 81 center) and the study of the gas and dust component associated to this evolved stellar population, hamper our understanding of whether this component may explain the observed temperature asymmetry toward the M 81 halo. ","Citation Text":["de Vries et al. 1987"],"Citation Start End":[[1007,1027]]} {"Identifier":"2022AandA...660A..24T__Mottez_(2015)_Instance_1","Paragraph":"Using a single-fluid approach Chian & Oliveira (1994, 1996), and Oliveira & Chian (1996) studied the effects of parametric instabilities on standing waves with applications to the magnetosphere. These authors developed a theory of MHD parametric instabilities driven by a left- or right-hand circularly polarised standing Alfvén wave in a low plasma-β under very specific initial conditions. Israelevich & Ofman (2004) and Israelevich & Ofman (2011) using both the MHD approach and hybrid simulations investigated numerically the generation of an electric field parallel to the magnetic field, due to non-linear induced ion-acoustic waves produced by the presence of a standing Alfvénic pump. In a different context, Mottez (2015) also explored the generation of a parallel electric field using PIC (particle in cell) simulations when two counter-propagating Alfvén waves are excited. However, the mechanism proposed by this author is not related to the ponderomotive force that it is usually operating under such conditions. A ponderomotive force (see the review of Lundin & Guglielmi 2006) generates density enhancements periodically in time and space which are normally called cavities and depend on gradients in density or electric fields. The periodicity depends on the value of gas pressure of the system and the amplitude of these enhancements is related quadratically with the amplitude of the initial transverse excitation (see also Rankin et al. 1994; Tikhonchuk et al. 1995). Interestingly, ponderomotive forces can lead to separation of species, although this topic is not addressed in the present work since the quasi-neutrality condition is imposed for the plasma composed of kinetic protons and the treatment of electrons is that of a fluid. Recently, Martínez-Gómez et al. (2018) used the multi-fluid approach to model high-frequency waves in partially ionised plasmas similar to those in quiescent solar prominences. These authors show that non-linear Alfvén waves generate density and pressure perturbations and that the friction due to collisions dissipates a fraction of the wave energy, which is transformed into heat that raises the temperature of the plasma.","Citation Text":["Mottez (2015)","Lundin & Guglielmi 2006"],"Citation Start End":[[717,730],[1067,1090]]} {"Identifier":"2022AandA...660A..2Oliveira_&_Chian_(1996)_Instance_1","Paragraph":"Using a single-fluid approach Chian & Oliveira (1994, 1996), and Oliveira & Chian (1996) studied the effects of parametric instabilities on standing waves with applications to the magnetosphere. These authors developed a theory of MHD parametric instabilities driven by a left- or right-hand circularly polarised standing Alfvén wave in a low plasma-β under very specific initial conditions. Israelevich & Ofman (2004) and Israelevich & Ofman (2011) using both the MHD approach and hybrid simulations investigated numerically the generation of an electric field parallel to the magnetic field, due to non-linear induced ion-acoustic waves produced by the presence of a standing Alfvénic pump. In a different context, Mottez (2015) also explored the generation of a parallel electric field using PIC (particle in cell) simulations when two counter-propagating Alfvén waves are excited. However, the mechanism proposed by this author is not related to the ponderomotive force that it is usually operating under such conditions. A ponderomotive force (see the review of Lundin & Guglielmi 2006) generates density enhancements periodically in time and space which are normally called cavities and depend on gradients in density or electric fields. The periodicity depends on the value of gas pressure of the system and the amplitude of these enhancements is related quadratically with the amplitude of the initial transverse excitation (see also Rankin et al. 1994; Tikhonchuk et al. 1995). Interestingly, ponderomotive forces can lead to separation of species, although this topic is not addressed in the present work since the quasi-neutrality condition is imposed for the plasma composed of kinetic protons and the treatment of electrons is that of a fluid. Recently, Martínez-Gómez et al. (2018) used the multi-fluid approach to model high-frequency waves in partially ionised plasmas similar to those in quiescent solar prominences. These authors show that non-linear Alfvén waves generate density and pressure perturbations and that the friction due to collisions dissipates a fraction of the wave energy, which is transformed into heat that raises the temperature of the plasma.","Citation Text":["Oliveira & Chian (1996)"],"Citation Start End":[[65,88]]} {"Identifier":"2022AandA...660A..2Israelevich_&_Ofman_(2004)_Instance_1","Paragraph":"Using a single-fluid approach Chian & Oliveira (1994, 1996), and Oliveira & Chian (1996) studied the effects of parametric instabilities on standing waves with applications to the magnetosphere. These authors developed a theory of MHD parametric instabilities driven by a left- or right-hand circularly polarised standing Alfvén wave in a low plasma-β under very specific initial conditions. Israelevich & Ofman (2004) and Israelevich & Ofman (2011) using both the MHD approach and hybrid simulations investigated numerically the generation of an electric field parallel to the magnetic field, due to non-linear induced ion-acoustic waves produced by the presence of a standing Alfvénic pump. In a different context, Mottez (2015) also explored the generation of a parallel electric field using PIC (particle in cell) simulations when two counter-propagating Alfvén waves are excited. However, the mechanism proposed by this author is not related to the ponderomotive force that it is usually operating under such conditions. A ponderomotive force (see the review of Lundin & Guglielmi 2006) generates density enhancements periodically in time and space which are normally called cavities and depend on gradients in density or electric fields. The periodicity depends on the value of gas pressure of the system and the amplitude of these enhancements is related quadratically with the amplitude of the initial transverse excitation (see also Rankin et al. 1994; Tikhonchuk et al. 1995). Interestingly, ponderomotive forces can lead to separation of species, although this topic is not addressed in the present work since the quasi-neutrality condition is imposed for the plasma composed of kinetic protons and the treatment of electrons is that of a fluid. Recently, Martínez-Gómez et al. (2018) used the multi-fluid approach to model high-frequency waves in partially ionised plasmas similar to those in quiescent solar prominences. These authors show that non-linear Alfvén waves generate density and pressure perturbations and that the friction due to collisions dissipates a fraction of the wave energy, which is transformed into heat that raises the temperature of the plasma.","Citation Text":["Israelevich & Ofman (2004)"],"Citation Start End":[[392,418]]} {"Identifier":"2022AandA...660A..2Martínez-Gómez_et_al._(2018)_Instance_1","Paragraph":"Using a single-fluid approach Chian & Oliveira (1994, 1996), and Oliveira & Chian (1996) studied the effects of parametric instabilities on standing waves with applications to the magnetosphere. These authors developed a theory of MHD parametric instabilities driven by a left- or right-hand circularly polarised standing Alfvén wave in a low plasma-β under very specific initial conditions. Israelevich & Ofman (2004) and Israelevich & Ofman (2011) using both the MHD approach and hybrid simulations investigated numerically the generation of an electric field parallel to the magnetic field, due to non-linear induced ion-acoustic waves produced by the presence of a standing Alfvénic pump. In a different context, Mottez (2015) also explored the generation of a parallel electric field using PIC (particle in cell) simulations when two counter-propagating Alfvén waves are excited. However, the mechanism proposed by this author is not related to the ponderomotive force that it is usually operating under such conditions. A ponderomotive force (see the review of Lundin & Guglielmi 2006) generates density enhancements periodically in time and space which are normally called cavities and depend on gradients in density or electric fields. The periodicity depends on the value of gas pressure of the system and the amplitude of these enhancements is related quadratically with the amplitude of the initial transverse excitation (see also Rankin et al. 1994; Tikhonchuk et al. 1995). Interestingly, ponderomotive forces can lead to separation of species, although this topic is not addressed in the present work since the quasi-neutrality condition is imposed for the plasma composed of kinetic protons and the treatment of electrons is that of a fluid. Recently, Martínez-Gómez et al. (2018) used the multi-fluid approach to model high-frequency waves in partially ionised plasmas similar to those in quiescent solar prominences. These authors show that non-linear Alfvén waves generate density and pressure perturbations and that the friction due to collisions dissipates a fraction of the wave energy, which is transformed into heat that raises the temperature of the plasma.","Citation Text":["Martínez-Gómez et al. (2018)"],"Citation Start End":[[1767,1795]]} {"Identifier":"2019AandA...623A..75V__Gandhi_et_al._2018a_Instance_1","Paragraph":"The X-ray transient MAXI J1820+070 was first detected on 2018 March 11 (Kawamuro et al. 2018) by the Monitor of All-sky X-ray Image (MAXI, Matsuoka et al. 2009) and was associated with the optical transient ASASSN-18ey (Denisenko 2018; Tucker et al. 2018). In the X-rays, the source flux exceeded 3 Crabs (Bozzo et al. 2018; Mereminskiy et al. 2018), and in the optical, the source reached a magnitude of mV = 12 − 13 (Littlefield 2018; Russell et al. 2018). The parallax of the source π = 0.3 ± 0.1 mas was presented in the Gaia DR2 catalogue (Gaia Collaboration 2018). This corresponds to a distance of \n\n\n\n3\n.\n\n9\n\n−\n1.3\n\n\n+\n3.3\n\n\n\n\n$ 3.9^{+3.3}_{-1.3} $\n\n\n kpc (Gandhi et al. 2018a). This unusually bright event allows a detailed investigation of multi-wavelength spectral and timing properties. The course of the outburst was monitored in radio (Trushkin et al. 2018; Polisensky et al. 2018), sub-millimeter (Tetarenko et al. 2018a), optical (Baglio et al. 2018), X-rays (Uttley et al. 2018), and γ-rays (Bozzo et al. 2018; Kuulkers et al. 2018). Because the object was sufficiently bright even for small telescopes, the target was almost continuously monitored, and a rich variety of phenomena was observed. Fast variability and powerful flares in the optical and infrared (Littlefield 2018; Sako et al. 2018; Gandhi et al. 2018b; Casella et al. 2018), optical, and X-ray quasi-periodic oscillations (Mereminskiy et al. 2018; Yu et al. 2018a,b; Buisson et al. 2018; Zampieri et al. 2018) as well as low linear polarisation (Berdyugin et al. 2018) were detected in the source. A 17 h photometric period was recently reported (Patterson et al. 2018) and was tentatively associated with the orbital or superhump period (previously, the source showed a 3.4 h periodicity, Richmond 2018). The X-ray spectral and timing properties as well as the optical-to-X-ray flux ratio suggests that the source is a black hole binary (Baglio et al. 2018; Mereminskiy et al. 2018).","Citation Text":["Gandhi et al. 2018a"],"Citation Start End":[[665,684]]} {"Identifier":"2019AandA...625A..12G__Nikolaou_et_al._2019_Instance_1","Paragraph":"We study the impact of secondary outgassing associated with partial melting and volcanism following accretion and a possible magma ocean phase. Raymond et al. (2007) showed that the accretion of planets around M-dwarf stars is faster than around more massive stars, which has also been calculated by Lissauer (2007) and Ida & Lin (2005). We therefore assumed that the accretion of a planet around an M dwarf is very fast (1 Myr), while for the other stellar cases we assumed an accretion time of 20 Myr. This corresponds to the lower limit in accretion times of Raymond et al. (2007) for planets around stars with masses greater than 0.8 MSun. After accretion, the planet may reside in a magma ocean stage, which we assume to last 1 Myr, following the results by Spohn & Schubert (1991) and Lebrun et al. (2013), among others. For high stellar irradiation, the planet may be trapped in a long-term magma ocean stage, which may last from several millions of years to billions of years (see e.g. Hamano et al. 2013, Nikolaou et al. 2019). For planets in a long-term magma ocean stage, Hamano et al. (2013) suggested very low water concentrations in the mantle at the end of the magma ocean stage because the planet can only exit this stage via severe atmospheric water loss because thick, water-rich atmospheres show a thermal blanketing effect suppressing the cooling of the planet via the Planck feedback. Their estimates of interior water reservoirs for such cases correspond to our lower limit of the initial mantle water concentration of 34 ppm. We nevertheless assumed in our calculations that the magma ocean has a short duration. This allows the high-luminosity pre-main sequence phase of the M dwarfs to have a larger impact on the HZ evolution. Any CO2 and H2O outgassed during the magma ocean phase is neglected in our calculations, i.e. we started our outgassing calculations with a 1 bar N2 atmosphere. Neglecting any atmospheric H2O and CO2 from the magma ocean phase results in a very narrow HZ at the beginning of our calculations, which is then only extended by secondary outgassing. This facilitates the evaluation of the potential of secondary outgassing from a stagnant-lid planet to form a HZ.","Citation Text":["Nikolaou et al. 2019"],"Citation Start End":[[1014,1034]]} {"Identifier":"2019AandA...625A..1Raymond_et_al._(2007)_Instance_1","Paragraph":"We study the impact of secondary outgassing associated with partial melting and volcanism following accretion and a possible magma ocean phase. Raymond et al. (2007) showed that the accretion of planets around M-dwarf stars is faster than around more massive stars, which has also been calculated by Lissauer (2007) and Ida & Lin (2005). We therefore assumed that the accretion of a planet around an M dwarf is very fast (1 Myr), while for the other stellar cases we assumed an accretion time of 20 Myr. This corresponds to the lower limit in accretion times of Raymond et al. (2007) for planets around stars with masses greater than 0.8 MSun. After accretion, the planet may reside in a magma ocean stage, which we assume to last 1 Myr, following the results by Spohn & Schubert (1991) and Lebrun et al. (2013), among others. For high stellar irradiation, the planet may be trapped in a long-term magma ocean stage, which may last from several millions of years to billions of years (see e.g. Hamano et al. 2013, Nikolaou et al. 2019). For planets in a long-term magma ocean stage, Hamano et al. (2013) suggested very low water concentrations in the mantle at the end of the magma ocean stage because the planet can only exit this stage via severe atmospheric water loss because thick, water-rich atmospheres show a thermal blanketing effect suppressing the cooling of the planet via the Planck feedback. Their estimates of interior water reservoirs for such cases correspond to our lower limit of the initial mantle water concentration of 34 ppm. We nevertheless assumed in our calculations that the magma ocean has a short duration. This allows the high-luminosity pre-main sequence phase of the M dwarfs to have a larger impact on the HZ evolution. Any CO2 and H2O outgassed during the magma ocean phase is neglected in our calculations, i.e. we started our outgassing calculations with a 1 bar N2 atmosphere. Neglecting any atmospheric H2O and CO2 from the magma ocean phase results in a very narrow HZ at the beginning of our calculations, which is then only extended by secondary outgassing. This facilitates the evaluation of the potential of secondary outgassing from a stagnant-lid planet to form a HZ.","Citation Text":["Raymond et al. (2007)"],"Citation Start End":[[144,165]]} {"Identifier":"2019AandA...625A..1Raymond_et_al._(2007)_Instance_2","Paragraph":"We study the impact of secondary outgassing associated with partial melting and volcanism following accretion and a possible magma ocean phase. Raymond et al. (2007) showed that the accretion of planets around M-dwarf stars is faster than around more massive stars, which has also been calculated by Lissauer (2007) and Ida & Lin (2005). We therefore assumed that the accretion of a planet around an M dwarf is very fast (1 Myr), while for the other stellar cases we assumed an accretion time of 20 Myr. This corresponds to the lower limit in accretion times of Raymond et al. (2007) for planets around stars with masses greater than 0.8 MSun. After accretion, the planet may reside in a magma ocean stage, which we assume to last 1 Myr, following the results by Spohn & Schubert (1991) and Lebrun et al. (2013), among others. For high stellar irradiation, the planet may be trapped in a long-term magma ocean stage, which may last from several millions of years to billions of years (see e.g. Hamano et al. 2013, Nikolaou et al. 2019). For planets in a long-term magma ocean stage, Hamano et al. (2013) suggested very low water concentrations in the mantle at the end of the magma ocean stage because the planet can only exit this stage via severe atmospheric water loss because thick, water-rich atmospheres show a thermal blanketing effect suppressing the cooling of the planet via the Planck feedback. Their estimates of interior water reservoirs for such cases correspond to our lower limit of the initial mantle water concentration of 34 ppm. We nevertheless assumed in our calculations that the magma ocean has a short duration. This allows the high-luminosity pre-main sequence phase of the M dwarfs to have a larger impact on the HZ evolution. Any CO2 and H2O outgassed during the magma ocean phase is neglected in our calculations, i.e. we started our outgassing calculations with a 1 bar N2 atmosphere. Neglecting any atmospheric H2O and CO2 from the magma ocean phase results in a very narrow HZ at the beginning of our calculations, which is then only extended by secondary outgassing. This facilitates the evaluation of the potential of secondary outgassing from a stagnant-lid planet to form a HZ.","Citation Text":["Raymond et al. (2007)"],"Citation Start End":[[562,583]]} {"Identifier":"2019AandA...625A..1Hamano_et_al._(2013)_Instance_1","Paragraph":"We study the impact of secondary outgassing associated with partial melting and volcanism following accretion and a possible magma ocean phase. Raymond et al. (2007) showed that the accretion of planets around M-dwarf stars is faster than around more massive stars, which has also been calculated by Lissauer (2007) and Ida & Lin (2005). We therefore assumed that the accretion of a planet around an M dwarf is very fast (1 Myr), while for the other stellar cases we assumed an accretion time of 20 Myr. This corresponds to the lower limit in accretion times of Raymond et al. (2007) for planets around stars with masses greater than 0.8 MSun. After accretion, the planet may reside in a magma ocean stage, which we assume to last 1 Myr, following the results by Spohn & Schubert (1991) and Lebrun et al. (2013), among others. For high stellar irradiation, the planet may be trapped in a long-term magma ocean stage, which may last from several millions of years to billions of years (see e.g. Hamano et al. 2013, Nikolaou et al. 2019). For planets in a long-term magma ocean stage, Hamano et al. (2013) suggested very low water concentrations in the mantle at the end of the magma ocean stage because the planet can only exit this stage via severe atmospheric water loss because thick, water-rich atmospheres show a thermal blanketing effect suppressing the cooling of the planet via the Planck feedback. Their estimates of interior water reservoirs for such cases correspond to our lower limit of the initial mantle water concentration of 34 ppm. We nevertheless assumed in our calculations that the magma ocean has a short duration. This allows the high-luminosity pre-main sequence phase of the M dwarfs to have a larger impact on the HZ evolution. Any CO2 and H2O outgassed during the magma ocean phase is neglected in our calculations, i.e. we started our outgassing calculations with a 1 bar N2 atmosphere. Neglecting any atmospheric H2O and CO2 from the magma ocean phase results in a very narrow HZ at the beginning of our calculations, which is then only extended by secondary outgassing. This facilitates the evaluation of the potential of secondary outgassing from a stagnant-lid planet to form a HZ.","Citation Text":["Hamano et al. (2013)"],"Citation Start End":[[1083,1103]]} {"Identifier":"2019MNRAS.484.5645V__Anderson_et_al._2016_Instance_1","Paragraph":"The theory of LK migration with STs involves two important time-scales. The first is the time-scale for quadrupole LK eccentricity oscillations, tLK, given by \n(40)\r\n\\begin{eqnarray*}\r\nt_{\\rm LK} &=& \\left(\\frac{10^6}{2\\pi }\\,\\text{yr}\\right)\\left(\\frac{M_\\mathrm{ b}}{\\rm{ M}_\\odot }\\right)^{-1}\\left(\\frac{M_*}{\\mathrm{ M}_\\odot }\\right)^{1\/2}\\left(\\frac{a_0}{1\\, \\text{au}}\\right)^{-3\/2}\\nonumber \\\\\r\n&&\\times \\, \\left(\\frac{a_{\\rm b,eff}}{100\\, \\text{au}}\\right)^{3} , \r\n\\end{eqnarray*}\r\nwhere a0 is the initial semimajor axis of the planet’s orbit, Mb is the mass of the (stellar) companion, and \n(41)\r\n\\begin{eqnarray*}\r\na_{\\rm b,eff} \\equiv a_{\\rm b} (1-e_{\\rm b}^2)^{1\/2} , \r\n\\end{eqnarray*}\r\nwith ab and eb the semimajor axis and eccentricity of the companion’s orbit, respectively. The time that the planet spends near the maximum eccentricity, emax, is of the order of (e.g. Anderson et al. 2016) \n(42)\r\n\\begin{eqnarray*}\r\n\\Delta t(e_{\\rm max}) \\sim (1-e_{\\rm max}^2)^{1\/2} t_{\\rm LK}. \r\n\\end{eqnarray*}\r\nThe second important time-scale is that of orbital decay due to STs given by (Alexander 1973; Hut 1981). \n(43)\r\n\\begin{eqnarray*}\r\nt^{-1}_{\\rm ST} &=& \\left|\\frac{\\skew4\\dot{a}}{a}\\right|_{\\rm ST} = (6 k_{2\\mathrm{ p}} \\Delta t_{\\mathrm{ L}}) \\frac{M_*}{M_\\mathrm{ p}} \\left(\\frac{R_\\mathrm{ p}}{a}\\right)^{5}\\frac{n^{2}}{(1-e^2)^{15\/2}} \\nonumber \\\\\r\n&&\\times \\, \\left[f_1(e)\\ - \\frac{f_2^2(e)}{f_5(e)}\\right], \r\n\\end{eqnarray*}\r\nwhere k2p is the tidal Love number of the planet, ΔtL is the lag time, f1(e) = 1 + 31e2\/2 + 255e4\/8 + 185e6\/16 + 25e8\/64, and f2(e) and f5(e) are given in equations (30) and (31), respectively. (We have assumed that the planet has a pseudo-synchronous spin rate.) Tidal dissipation is most efficient near the maximum eccentricity. Since the planet only spends a fraction (${\\sim } \\sqrt{1-e_{\\rm max}^2}$) of the time near emax, the effective orbital decay rate during LK migration is \n(44)\r\n\\begin{eqnarray*}\r\nt^{-1}_{\\rm ST,LK} &=& \\left(\\left|\\frac{\\skew4\\dot{a}}{a}\\right|_{\\rm ST} \\sqrt{1-e^2}\\right)_{e_{\\rm max}} \\nonumber \\\\\r\n&\\approx& \\frac{1.27}{{\\rm Gyr}} \\left(\\frac{k_{\\rm 2p}}{0.37}\\right) \\left(\\frac{\\Delta t_{\\rm L}}{1 {\\rm s}}\\right)\\left(\\frac{M_\\mathrm{ p}}{\\mathrm{ M}_{\\odot }}\\right)^2 \\left(\\frac{M_\\mathrm{ p}}{M_\\mathrm{ J}}\\right)^{-1} \\nonumber \\\\\r\n&&\\times \\; \\left(\\frac{R_\\mathrm{ p}}{R_\\mathrm{ J}}\\right)^5\\left(\\frac{a_0}{1\\, {\\rm au}}\\right)^{-1} \\left(\\frac{r_{\\rm p, min}}{0.025\\, {\\rm au}}\\right)^{-7} \\,,\r\n\\end{eqnarray*}\r\nwhere rp, min = a0(1 − emax) is the minimum pericentre distance (in the second of the above equalities, we have used emax = 0.96). Successful migration within a few Gyr requires rp, min ≲ 0.025 au, corresponding to a final (circularized) planet semimajor axis aF ≲ 0.05 au. A planet would need to be more dissipative than Jupiter (larger ΔtL)5 to become an HJ with a larger aF.","Citation Text":["Anderson et al. 2016"],"Citation Start End":[[902,922]]} {"Identifier":"2015AandA...574A..49A__Cardamone_et_al._(2010)_Instance_1","Paragraph":"Several optical\/near-UV surveys have targeted the CDF-S and its flanking fields, with the main purpose of photometrically and spectroscopically calculating the redshifts of the detectable sources. In the context of the ESO imaging survey (EIS, Arnouts et al. 2001) project, multi-colour (six broad band filters, U′UBVRI) photometric measurements of about 75 000 sources have been provided to observe the Extended-CDF-S (E-CDF-S) through the Wide Field Imager (WFI, Baade et al. 1998, 1999) at the MPG\/ESO 2.2 m telescope on La Silla. By means of the same telescope and instrument, a nearly coincident area of 31.5 × 30 arcmin2 has been observed in 17 passbands (350–930 nm) within the COMBO-17 survey, obtaining a catalogue of more than 60 000 objects including astrometry, classification, and photometric redshifts, with around 10 000 galaxies identified at RVega 24 (Wolf et al. 2004, 2008). Another optical and near-IR multi-wavelength survey has been developed by Cardamone et al. (2010) as part of the Multi-Wavelength Survey by Yale-Chile (MUSYC, Gawiser et al. 2006), combining the Subaru 18-bands imaging (400–900 nm) to 14 other available ground-based and Spitzer images: about 80 000 galaxies are catalogued at R ≤ 27, and about 30 000 redshifts are computed. The Great Observatories Origins Deep Survey (GOODS, Giavalisco et al. 2004), instead, covers a 320 arcmin2 region in the CDF-S (GOODS-S) by using the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS, Ford et al. 2003), through the filters F435W,F606W,F775W, and F850LP; it catalogued about 29 600 objects, at m ≤ 27. Moreover, an 11 arcmin2 region within the GOODS-S (Hubble Ultra Deep Field, UDF, Beckwith et al. 2006) has been deeply observed by the ACS in the same bands, reaching a uniform limiting magnitude m ~ 29 for point sources. Voyer et al. (2009) also presented the U-band observations of the same area, achieved through the HST Wide-Field Planetary Camera 2 (WFPC2)\/F300W filter (λmax ~ 300 nm) and providing a catalogue of 96 objects. The Arizona CDFS Environment Survey (ACES, Cooper et al. 2012) spectroscopically targeted the E-CDF-S by means of the Inamori-Magellan Areal Camera and Spectrograph on the Magellan-Baade telescope (565–920 nm), yielding more than 5000 redshifts for R ≤ 24.1 sources; it widens therefore previous sets of spectroscopic redshift estimates of CDF-S sources (e.g. Szokoly et al. 2004; Le Fèvre et al. 2005; Ravikumar et al. 2007; Popesso et al. 2009; Balestra et al. 2010; Silverman et al. 2010), for a total of about 1300 ACES objects with comparison published redshifts. All the publicly available spectroscopic redshift estimates in the CDF-S have been compiled in the ESO CDF-S Master Catalogue, version 3.01. ","Citation Text":["Cardamone et al. (2010)"],"Citation Start End":[[968,991]]} {"Identifier":"2019MNRAS.484.5645V__Hut_1981_Instance_1","Paragraph":"The theory of LK migration with STs involves two important time-scales. The first is the time-scale for quadrupole LK eccentricity oscillations, tLK, given by \n(40)\r\n\\begin{eqnarray*}\r\nt_{\\rm LK} &=& \\left(\\frac{10^6}{2\\pi }\\,\\text{yr}\\right)\\left(\\frac{M_\\mathrm{ b}}{\\rm{ M}_\\odot }\\right)^{-1}\\left(\\frac{M_*}{\\mathrm{ M}_\\odot }\\right)^{1\/2}\\left(\\frac{a_0}{1\\, \\text{au}}\\right)^{-3\/2}\\nonumber \\\\\r\n&&\\times \\, \\left(\\frac{a_{\\rm b,eff}}{100\\, \\text{au}}\\right)^{3} , \r\n\\end{eqnarray*}\r\nwhere a0 is the initial semimajor axis of the planet’s orbit, Mb is the mass of the (stellar) companion, and \n(41)\r\n\\begin{eqnarray*}\r\na_{\\rm b,eff} \\equiv a_{\\rm b} (1-e_{\\rm b}^2)^{1\/2} , \r\n\\end{eqnarray*}\r\nwith ab and eb the semimajor axis and eccentricity of the companion’s orbit, respectively. The time that the planet spends near the maximum eccentricity, emax, is of the order of (e.g. Anderson et al. 2016) \n(42)\r\n\\begin{eqnarray*}\r\n\\Delta t(e_{\\rm max}) \\sim (1-e_{\\rm max}^2)^{1\/2} t_{\\rm LK}. \r\n\\end{eqnarray*}\r\nThe second important time-scale is that of orbital decay due to STs given by (Alexander 1973; Hut 1981). \n(43)\r\n\\begin{eqnarray*}\r\nt^{-1}_{\\rm ST} &=& \\left|\\frac{\\skew4\\dot{a}}{a}\\right|_{\\rm ST} = (6 k_{2\\mathrm{ p}} \\Delta t_{\\mathrm{ L}}) \\frac{M_*}{M_\\mathrm{ p}} \\left(\\frac{R_\\mathrm{ p}}{a}\\right)^{5}\\frac{n^{2}}{(1-e^2)^{15\/2}} \\nonumber \\\\\r\n&&\\times \\, \\left[f_1(e)\\ - \\frac{f_2^2(e)}{f_5(e)}\\right], \r\n\\end{eqnarray*}\r\nwhere k2p is the tidal Love number of the planet, ΔtL is the lag time, f1(e) = 1 + 31e2\/2 + 255e4\/8 + 185e6\/16 + 25e8\/64, and f2(e) and f5(e) are given in equations (30) and (31), respectively. (We have assumed that the planet has a pseudo-synchronous spin rate.) Tidal dissipation is most efficient near the maximum eccentricity. Since the planet only spends a fraction (${\\sim } \\sqrt{1-e_{\\rm max}^2}$) of the time near emax, the effective orbital decay rate during LK migration is \n(44)\r\n\\begin{eqnarray*}\r\nt^{-1}_{\\rm ST,LK} &=& \\left(\\left|\\frac{\\skew4\\dot{a}}{a}\\right|_{\\rm ST} \\sqrt{1-e^2}\\right)_{e_{\\rm max}} \\nonumber \\\\\r\n&\\approx& \\frac{1.27}{{\\rm Gyr}} \\left(\\frac{k_{\\rm 2p}}{0.37}\\right) \\left(\\frac{\\Delta t_{\\rm L}}{1 {\\rm s}}\\right)\\left(\\frac{M_\\mathrm{ p}}{\\mathrm{ M}_{\\odot }}\\right)^2 \\left(\\frac{M_\\mathrm{ p}}{M_\\mathrm{ J}}\\right)^{-1} \\nonumber \\\\\r\n&&\\times \\; \\left(\\frac{R_\\mathrm{ p}}{R_\\mathrm{ J}}\\right)^5\\left(\\frac{a_0}{1\\, {\\rm au}}\\right)^{-1} \\left(\\frac{r_{\\rm p, min}}{0.025\\, {\\rm au}}\\right)^{-7} \\,,\r\n\\end{eqnarray*}\r\nwhere rp, min = a0(1 − emax) is the minimum pericentre distance (in the second of the above equalities, we have used emax = 0.96). Successful migration within a few Gyr requires rp, min ≲ 0.025 au, corresponding to a final (circularized) planet semimajor axis aF ≲ 0.05 au. A planet would need to be more dissipative than Jupiter (larger ΔtL)5 to become an HJ with a larger aF.","Citation Text":["Hut 1981"],"Citation Start End":[[1126,1134]]} {"Identifier":"2015AandA...576A.104P__Benoît_et_al._(2004)_Instance_1","Paragraph":"Figure 5 shows that, toward the Galactic plane,\n ⟨ B⊥\n ⟩ is mostly oriented along the plane, corresponding to a polarization\n angle close to 0°. This is\n especially the case toward the outer MW regions. There are a few exceptions, in particular\n toward lines of sight that are tangent to spiral arms (Cygnus X, ℓII ≃ 81°,\n bII ≃\n 0°; Carina, ℓII ≃ 277°, bII ≃ −9°),\n where the polarization signal is actually the smallest in the plane because in those\n regions the large-scale magnetic field is parallel to the LOS. This was already noted by\n Heiles (1996) (and references therein) and Benoît et al. (2004). We also note that the homogeneity\n of the field orientation being parallel to the plane extends away from the plane and up to\n | bII | ≃\n 10° in many regions (in particular the Fan). At intermediate latitudes,\n the field orientation follows a few of the well known filamentary intensity structures of\n the local ISM. In particular, this is the case for the Aquila Rift and most of Loop I\n (outside the latitude range bII ≃ 50°−60°), where the structure of\n ⟨ B⊥\n ⟩ follows the intensity flare and loop elongation. As addressed\n earlier, this orientation of ⟨\n B⊥ ⟩ in those regions was\n already noted in the synchrotron polarized maps of WMAP (Gold et al. 2011). Other regions, however, show a variety of relative\n orientations between the field projection and intensity structures, which can also be\n orthogonal in some instances. Thus studies with Planck submillimetre\n polarization (Planck Collaboration Int. XXXII 2015;\n Planck Collaboration Int. XXXIII 2015) hold\n promise as a valuable complement to optical and near infrared polarization studies of the\n relative orientation of the magnetic field and structure (e.g., Goodman et al. 1990; Chapman et al.\n 2011). ","Citation Text":["Benoît et al. (2004)"],"Citation Start End":[[686,706]]} {"Identifier":"2018ApJ...859...49P__Marcha_et_al._1996_Instance_1","Paragraph":"Blazars are the subclass of active galactic nuclei (AGNs) characterized by a relativistic jet that is aligned close (≤10°) to the observer's line of sight (Urry & Padovani 1995). The Doppler-boosted non-thermal emission from the relativistic jets is highly variable at all observed timescales over essentially the entire electromagnetic spectrum. Variability seen over a timescale of less than a day is called intraday variability (IDV), or microvariability (Wagner & Witzel 1995), variations over a few days to months are often called short-term variability (STV), and fluctuations observed over several months to years, or even decades, are known as long-term variability (LTV; Gupta et al. 2004). The two classical subclasses of blazars are BL Lacertae objects (BL Lacs), which have no detectable, or very weak (EW 5Å), optical emission lines (Marcha et al. 1996), and flat spectrum radio quasars (FSRQs), which have the usual strong quasar emission lines in their optical spectra. The two broad bumps seen in the broadband spectral energy distributions (SEDs) of blazars indicate two different emission mechanisms. The low-energy peak is well understood to be caused by the synchrotron emission from relativistic electrons in the jet. However, the origin of the high-energy peak is still under debate. In the leptonic model, the high-energy component is interpreted as the inverse Compton (IC) scattering of synchrotron photons themselves (synchrotron-self Compton, SSC; e.g., Bloom & Marscher 1996), or external photons (external Compton, EC; e.g., Blandford & Levinson 1995) by the same electrons responsible for the synchrotron emission. In the alternative hadronic models, processes such as proton and muon synchrotron emission are thought to be responsible for the high-energy bump (e.g., Böttcher 2007). Blazars are also classified through the value of the peak frequency of the synchrotron component. It typically lies in the infrared to optical region in the low-frequency peak blazars (LBL), while in the high-frequency peaked blazars (HBL) it is located at FUV to X-ray energies (Padovani & Giommi 1995). The high-energy components of blazar SEDs peak at GeV energies in LBLs and at TeV energies in HBLs, but some LBLs and the intermediate-peaked blazars (IBLs) have still been detected at TeV energies.","Citation Text":["Marcha et al. 1996"],"Citation Start End":[[848,866]]} {"Identifier":"2020MNRAS.497..204Y__Piórkowska_et_al._2013_Instance_1","Paragraph":"Now we estimate the average number of strong lensing systems within the region of possible GW sky location ($\\mathbf {\\delta \\Omega }$), and capable of reproducing the observed ΔtGW and RGW. The probability for an object at redshift zs being strongly lensed by a foreground galaxy with redshift in [zl, zl + dzl] and velocity dispersion in [σv, σv + dσv] is \n(2)$$\\begin{eqnarray*}\r\n{\\rm d}\\tau = \\frac{{\\rm d}n(\\sigma _v,z_l)}{{\\rm d}\\sigma _v}S_{cr}(\\sigma _v,z_l,z_s)\\frac{{\\rm d}V(z_l)}{{\\rm d}z_l}{\\rm d}\\sigma _v{\\rm d}z_l.\r\n\\end{eqnarray*}$$Here n(σv, zl) is the comoving number density of the lens galaxies per unit velocity dispersion σv at redshift zl. $S_{cr}(\\sigma _v,z_l,z_s)=\\pi \\theta _E^2$ is the cross-section for a lens of velocity dispersion σv at zl and a source at zs. V(zl) is the comoving volume within zl. For simplicity and consistency with previous research on detection rate of SLGWs for ET (Piórkowska et al. 2013; Biesiada et al. 2014; Li et al. 2018), we ignore the redshift dependence of n(σv, zl), and adopt the following Schechter distribution function \n(3)$$\\begin{eqnarray*}\r\n\\frac{{\\rm d}n(\\sigma _v,z_l)}{{\\rm d}\\sigma _v} = n_*\\left(\\frac{\\sigma _v}{\\sigma _{v*}}\\right)^\\alpha \\exp \\left[-\\left(\\frac{\\sigma _v}{\\sigma _{v*}}\\right)^\\beta \\right]\\frac{\\beta }{\\Gamma (\\alpha \/\\beta)}\\frac{1}{\\sigma _v},\r\n\\end{eqnarray*}$$where $(n_*,\\sigma _{v*},\\alpha ,\\beta)=(8.0\\times 10^{-3}\\, h^3\\, {\\rm Mpc^{-3}},161\\, {\\rm km\\, s}^{-1}, 2.32$, $2.67)$ comes from the galaxy sample of SDSS DR5 (Choi, Park & Vogeley 2007). Γ(α\/β) is the Gamma function. Integrating equation (2), one obtains the probability for an object at redshift zs being strongly lensed. It is (Piórkowska et al. 2013) \n(4)$$\\begin{eqnarray*}\r\n\\tau (z_s)=\\frac{8}{15}\\pi ^3(1+z_s)^3d_s^3\\left(\\frac{\\sigma _{v*}}{c}\\right)^4n_*\\frac{\\Gamma (\\frac{4+\\alpha }{\\beta })}{\\Gamma (\\alpha \/\\beta)}.\r\n\\end{eqnarray*}$$To estimate the expected number of strongly lensed galaxies in redshift range (zs, zs + δzs), we need the redshift distribution of source galaxies. Here we approximate it by (Holz & Hughes 2005) \n(5)$$\\begin{eqnarray*}\r\n\\frac{{\\rm d}N}{{\\rm d}r}=N_0r^a\\exp (-(r\/r_*)^b),\r\n\\end{eqnarray*}$$where (a, b, r*) = (1, 4, c\/H0) and r is the comoving distance (Kaiser 1992; Hu 1999). The normalization factor N0 is chosen to satisfy $\\int \\frac{{\\rm d}N}{{\\rm d}r} {\\rm d}r=40 \\, \\rm galaxies\\, arcmin^{-2}$, corresponding to several important survey projects in the future like LSST, WFIRST, and Euclid (Yao et al. 2017). Then the expected number of strongly lensed galaxies in redshift range (zs, zs + δzs) will be \n(6)$$\\begin{eqnarray*}\r\nN_{\\rm lg} = \\int _{z_s}^{z_s+\\delta z_s} \\tau (z)\\frac{{\\rm d}N}{{\\rm d}r}\\frac{{\\rm d}r(z)}{{\\rm d}z}{\\rm d}z.\r\n\\end{eqnarray*}$$The normalized differential distribution of the expected number of the lensed galaxies is shown as Fig. 1. It shows that most of lensed galaxies distribute in the range of redshift (0.5, 2.5) and the distribution peaks at z ≈ 1.5.","Citation Text":["Piórkowska et al. 2013"],"Citation Start End":[[920,942]]} {"Identifier":"2020MNRAS.497..204Y__Piórkowska_et_al._2013_Instance_2","Paragraph":"Now we estimate the average number of strong lensing systems within the region of possible GW sky location ($\\mathbf {\\delta \\Omega }$), and capable of reproducing the observed ΔtGW and RGW. The probability for an object at redshift zs being strongly lensed by a foreground galaxy with redshift in [zl, zl + dzl] and velocity dispersion in [σv, σv + dσv] is \n(2)$$\\begin{eqnarray*}\r\n{\\rm d}\\tau = \\frac{{\\rm d}n(\\sigma _v,z_l)}{{\\rm d}\\sigma _v}S_{cr}(\\sigma _v,z_l,z_s)\\frac{{\\rm d}V(z_l)}{{\\rm d}z_l}{\\rm d}\\sigma _v{\\rm d}z_l.\r\n\\end{eqnarray*}$$Here n(σv, zl) is the comoving number density of the lens galaxies per unit velocity dispersion σv at redshift zl. $S_{cr}(\\sigma _v,z_l,z_s)=\\pi \\theta _E^2$ is the cross-section for a lens of velocity dispersion σv at zl and a source at zs. V(zl) is the comoving volume within zl. For simplicity and consistency with previous research on detection rate of SLGWs for ET (Piórkowska et al. 2013; Biesiada et al. 2014; Li et al. 2018), we ignore the redshift dependence of n(σv, zl), and adopt the following Schechter distribution function \n(3)$$\\begin{eqnarray*}\r\n\\frac{{\\rm d}n(\\sigma _v,z_l)}{{\\rm d}\\sigma _v} = n_*\\left(\\frac{\\sigma _v}{\\sigma _{v*}}\\right)^\\alpha \\exp \\left[-\\left(\\frac{\\sigma _v}{\\sigma _{v*}}\\right)^\\beta \\right]\\frac{\\beta }{\\Gamma (\\alpha \/\\beta)}\\frac{1}{\\sigma _v},\r\n\\end{eqnarray*}$$where $(n_*,\\sigma _{v*},\\alpha ,\\beta)=(8.0\\times 10^{-3}\\, h^3\\, {\\rm Mpc^{-3}},161\\, {\\rm km\\, s}^{-1}, 2.32$, $2.67)$ comes from the galaxy sample of SDSS DR5 (Choi, Park & Vogeley 2007). Γ(α\/β) is the Gamma function. Integrating equation (2), one obtains the probability for an object at redshift zs being strongly lensed. It is (Piórkowska et al. 2013) \n(4)$$\\begin{eqnarray*}\r\n\\tau (z_s)=\\frac{8}{15}\\pi ^3(1+z_s)^3d_s^3\\left(\\frac{\\sigma _{v*}}{c}\\right)^4n_*\\frac{\\Gamma (\\frac{4+\\alpha }{\\beta })}{\\Gamma (\\alpha \/\\beta)}.\r\n\\end{eqnarray*}$$To estimate the expected number of strongly lensed galaxies in redshift range (zs, zs + δzs), we need the redshift distribution of source galaxies. Here we approximate it by (Holz & Hughes 2005) \n(5)$$\\begin{eqnarray*}\r\n\\frac{{\\rm d}N}{{\\rm d}r}=N_0r^a\\exp (-(r\/r_*)^b),\r\n\\end{eqnarray*}$$where (a, b, r*) = (1, 4, c\/H0) and r is the comoving distance (Kaiser 1992; Hu 1999). The normalization factor N0 is chosen to satisfy $\\int \\frac{{\\rm d}N}{{\\rm d}r} {\\rm d}r=40 \\, \\rm galaxies\\, arcmin^{-2}$, corresponding to several important survey projects in the future like LSST, WFIRST, and Euclid (Yao et al. 2017). Then the expected number of strongly lensed galaxies in redshift range (zs, zs + δzs) will be \n(6)$$\\begin{eqnarray*}\r\nN_{\\rm lg} = \\int _{z_s}^{z_s+\\delta z_s} \\tau (z)\\frac{{\\rm d}N}{{\\rm d}r}\\frac{{\\rm d}r(z)}{{\\rm d}z}{\\rm d}z.\r\n\\end{eqnarray*}$$The normalized differential distribution of the expected number of the lensed galaxies is shown as Fig. 1. It shows that most of lensed galaxies distribute in the range of redshift (0.5, 2.5) and the distribution peaks at z ≈ 1.5.","Citation Text":["Piórkowska et al. 2013"],"Citation Start End":[[1697,1719]]} {"Identifier":"2016ApJ...817..129B__Kennel_&_Coroniti_1984_Instance_1","Paragraph":"The PWN morphology depends on the pulsar’s Mach number \n\n\n\n\n\n, where v is the pulsar’s velocity and cs is the speed of sound in the ambient medium. Because even the transverse velocity of B0656+14, \n\n\n\n\n\n km s−1 (Brisken et al. 2003)—where i is the angle between the velocity vector and the line of sight—exceeds the typical speed of sound in the ISM, \n\n\n\n\n\n–30 km s−1, the pulsar moves supersonically and the interaction of its wind with the ISM should produce a bow-shock PWN. X-ray emission from such a PWN is due to synchrotron radiation from the shocked pulsar wind outside the termination shock (TS). For large \n\n\n\n\n\n and small values of the magnetization parameter σ of the preshock isotropic wind (Kennel & Coroniti 1984), the TS acquires a bullet-like shape (Bucciantini et al. 2005) with a distance \n\n\n\n\n\n between the pulsar and bullet head, where \n\n\n\n\n\n dyn cm−2 is the ram pressure, \n\n\n\n\n\n is the mass density of the ambient medium, \n\n\n\n\n\n (in units of cm−3), and \n\n\n\n\n\n. The bullet’s cylindrical radius is \n\n\n\n\n\n and the distance of its back surface from the pulsar is \n\n\n\n\n\n. The shocked wind outside the TS is confined by the contact discontinuity (CD) surface, which has an approximately cylindrical shape behind the bullet, with a radius \n\n\n\n\n\n. The shocked wind flows along and past the bullet, reaching very high flow velocities: ∼(0.1–0.3)c in the “inner channel” (\n\n\n\n\n\n) and up to (0.8–0.9)c in the “outer channel” (\n\n\n\n\n\n) of the collimated outflow. The appearance of such a PWN depends on the velocity orientation angle i. For i close to 90°, the PWN would look like a bow-shock structure accompanied by a tail of collimated wind outflow. However, for small \n\n\n\n\n\n the PWN would look nearly round because of the projection effect. Because the emission from the nearly relativistic flow is predominantly directed along the flow velocity, the apparent PWN radius \n\n\n\n\n\n is smaller, \n\n\n\n\n\n, in the case of approaching pulsar than in the case of receding pulsar, when \n\n\n\n\n\n.","Citation Text":["Kennel & Coroniti 1984"],"Citation Start End":[[706,728]]} {"Identifier":"2015ApJ...806....1M__Doi_et_al._2010_Instance_1","Paragraph":"For the clustering measurements, we use the sample of galaxies compiled in Data Release 11 (DR11) of the SDSS-III project. The SDSS-III is a spectroscopic investigation of galaxies and quasars selected from the imaging data obtained by the SDSS (York et al. 2000) I\/II covering about 11,000 deg2 (Abazajian et al. 2009) using the dedicated 2.5 m SDSS Telescope (Gunn et al. 2006). The imaging employed a drift-scan mosaic CCD camera (Gunn et al. 1998) with five photometric bands (\n\n\n\n\n\n and z; Fukugita et al. 1996; Smith et al. 2002; Doi et al. 2010). The SDSS-III (Eisenstein et al. 2011) BOSS project (Ahn et al. 2012; Dawson et al. 2013) obtained additional imaging data of about 3000 deg2 (Aihara et al. 2011). The imaging data was processed by a series of pipelines (Lupton et al. 2001; Pier et al. 2003; Padmanabhan et al. 2008) and corrected for Galactic extinction (Schlegel et al. 1998) to obtain a reliable photometric catalog. This catalog was used as an input to select targets for spectroscopy (Dawson et al. 2013) for conducting the BOSS survey (Ahn et al. 2012) with the SDSS spectrographs (Smee et al. 2013). Targets are assigned to tiles of diameter 3° using an adaptive tiling algorithm designed to maximize the number of targets that can be successfully observed (Blanton et al. 2003). The resulting data were processed by an automated pipeline which performs spectral classification, redshift determination, and various parameter measurements, e.g., the stellar-mass measurements from a number of different stellar population synthesis codes which utilize the photometry and redshifts of the individual galaxies (Bolton et al. 2012). In addition to the galaxies targeted by the BOSS project, we also use galaxies that pass the target selection but have already been observed as part of the SDSS-I\/II project (legacy galaxies). These legacy galaxies are subsampled in each sector so that they obey the same completeness as that of the CMASS sample (Anderson et al. 2014).","Citation Text":["Doi et al. 2010"],"Citation Start End":[[536,551]]} {"Identifier":"2020ApJ...897...38D__Goedbloed_&_Poedts_2004_Instance_1","Paragraph":"The linearized equation of motion (see derivation of Equation (A12)) for the unmagnetized case is given by (also refer to Christensen-Dalsgaard 2003):\n9\n\n\n\n\n\nwhere cs(r), ρ0(r), and g(r) are the sound speed, density, and gravity (directed radially inward), respectively, and \n\n\n\n\n\n denotes the covariant spatial derivative operator. For all ensuing calculations and derivations, we write Equation (9) in the form \n\n\n\n\n\n, where the magnetically unperturbed wave operator \n\n\n\n\n\n is self-adjoint (Goedbloed & Poedts 2004). To solve for the eigenmodes of the unperturbed model S, the boundary conditions employed are: (a) \n\n\n\n\n\n and the Eulerian pressure perturbation at r = 0 are finite, and (b) the Lagrangian pressure perturbation at r = R⊙ vanishes (see Section 17.6 in Cox 1980). As already mentioned earlier, the Cowling approximation is used, and hence, the gravitational Poisson equation is not needed while finding the eigenmodes. We suppress the subscript “0” in the unperturbed eigenfunctions \n\n\n\n\n\n and eigenfrequencies ωk,0 for the rest of this paper. Unless specified otherwise, any instance of ωk or \n\n\n\n\n\n should be assumed to imply eigenfrequencies and eigenfunctions of Equation (9), respectively. The Sun is treated as a fluid body with a vanishing shear modulus and, hence, is unable to sustain shear waves (although the presence of magnetic fields complicates this assumption). Thus, the eigenfunctions of the background model contain no toroidal components (see Chapter 8 of Dahlen & Tromp 1998), rendering them purely spheroidal. We write the displacement field \n\n\n\n\n\n in the basis of vector spherical harmonics (and thereafter GSH) as follows:\n10\n\n\n\n\n\n\n\n11\n\n\n\n\n\nHere, \n\n\n\n\n\n denote spherical polar coordinates, with basis vectors \n\n\n\n\n\n and \n\n\n\n\n\n where n is the radial order, ℓ is the angular degree, and m is the azimuthal order. The dimensionless lateral covariant derivative operator is denoted by \n\n\n\n\n\n. The basis vectors in spherical polar coordinates are related to those in the GSH basis via\n12\n\n\n\n\n\n\n","Citation Text":["Goedbloed & Poedts 2004"],"Citation Start End":[[494,517]]} {"Identifier":"2015MNRAS.450.1638G__Hall_&_Vinen_1956a_Instance_1","Paragraph":"Equation (1) describes the departure of the system from a ‘background’, time-independent state of exact corotation, where this departure is driven by $\\dot{\\boldsymbol {\\Omega }}$. As a consequence, all quantities appearing in (1) are perturbations with respect to the corotating state. For instance, the magnetic field can be decomposed into a fixed background part, $\\boldsymbol {B}_0$, plus a small, spin-down-induced perturbation, $\\boldsymbol {b} \\equiv \\delta \\boldsymbol {B}$, i.e.\n\n(4)\n\n\\begin{equation}\n\\boldsymbol {B} \\approx \\boldsymbol {B}_0 + \\boldsymbol {b}.\n\\end{equation}\n\nThe magnetic force can therefore be expressed to leading order\n\n(5)\n\n\\begin{equation}\n\\boldsymbol {F}_{\\rm mag} \\approx - \\nabla \\left(\\frac{\\boldsymbol {B}_0 \\cdot \\boldsymbol {b} }{4\\pi } \\right) + \\frac{1}{4\\pi } \\left[ (\\boldsymbol {b} \\cdot \\nabla ) \\boldsymbol {B}_0 + (\\boldsymbol {B}_0 \\cdot \\nabla ) \\boldsymbol {b} \\right].\n\\end{equation}\n\nThe nature of the coupling force, $\\boldsymbol {F}_{\\rm cpl}$, is determined by the interaction between the superfluid's quantized vortices and the other components of the star (e.g. protons, electrons, the magnetic field). The simplest form for this force is provided by the Hall & Vinen mutual friction force (Hall & Vinen 1956a,b)\n\n(6)\n\n\\begin{equation}\n\\boldsymbol {F}_{\\rm cpl} = 2\\Omega _{\\rm n}\\rho _{\\rm n}\\left\\lbrace {\\cal B}\\left[ \\hat{\\boldsymbol {z}} \\times (\\hat{\\boldsymbol {z}} \\times \\boldsymbol {w}) \\right]+ {\\cal B}^\\prime (\\hat{\\boldsymbol {z}} \\times \\boldsymbol {w}) \\right\\rbrace ,\n\\end{equation}\n\nwhere $\\boldsymbol {w}= \\boldsymbol {v}_{\\rm n}-\\boldsymbol {v}_{\\rm p}$ is the velocity lag between the neutrons and the charged particles, ${\\cal B}$ and ${\\cal B}^\\prime$ are mutual friction coefficients (which we take to be uniform throughout the star) and a ‘hat’ denotes a unit vector. This form of the force assumes a vortex array aligned with the common spin axis. According to our setup of the problem we have,\n\n(7)\n\n\\begin{equation}\n\\boldsymbol {w} \\approx \\varpi (\\Omega _{\\rm n}-\\Omega _{\\rm p}) \\hat{\\varphi } \\equiv \\varpi \\Omega _{\\rm np}\\hat{\\bf {\\varphi }},\n\\end{equation}\n\nwhere ϖ = rsin θ is the usual cylindrical radius. The mutual friction coupling force becomes\n\n(8)\n\n\\begin{equation}\n\\boldsymbol {F}_{\\rm cpl} = -2\\varpi \\rho _{\\rm n}\\Omega _{\\rm n}\\Omega _{\\rm np}\\left({\\cal B}\\hat{\\varphi } + {\\cal B}^\\prime \\hat{\\varpi}\\right).\n\\end{equation}\n\nThe most commonly considered mutual friction mechanism in neutron star cores is the scattering of electrons by the magnetic field of individual vortices, in which case ${\\cal B}^\\prime \\ll {\\cal B}\\sim 10^{-4}$ (Alpar et al. 1984; Andersson, Sidery & Comer 2006).","Citation Text":["Hall & Vinen 1956a"],"Citation Start End":[[1251,1269]]} {"Identifier":"2022MNRAS.517.2502S__Kakuwa_2016_Instance_1","Paragraph":"The first equation describes the time evolution of f(p), the momentum distribution of the non-thermal particles, from here on supposed to be relativistic electrons, since we are considering a leptonic model:\n(1)$$\\begin{eqnarray*}\r\n\\frac{\\partial f}{\\partial t} = \\frac{1}{p^2} \\frac{\\partial }{\\partial p} \\left[ p^2 D_p \\frac{\\partial f}{\\partial p} + p^2 \\left(\\frac{\\partial p}{\\partial t} \\right)_{\\text{rad}} f \\right] + \\frac{f}{t_\\text{esc}} +I_f ,\r\n\\end{eqnarray*}$$where p is the particle momentum, Dp the momentum diffusion coefficient, (∂p\/∂t)rad the cooling coefficient due to radiative emission, and If is the particle injection rate. Starting from momentum distribution, it is possible to calculate the electron energy density, in fact n(γ) = 4πp2f(p)mec, where me is the electron mass. Supposing only parallel and antiparallel propagating magnetohydrodynamic (MHD) waves interacting with electrons, the acceleration time can be estimated as (Miller & Roberts 1995; Kakuwa 2016):\n(2)$$\\begin{eqnarray*}\r\nt_\\text{acc} = \\left[ \\frac{2 \\beta _w^2 c}{U_B r_g}\\int _{k\\gt k_\\text{res}} \\frac{W_B(k)}{k} dk \\right]^{-1} ,\r\n\\end{eqnarray*}$$where βw = va\/c is the wave velocity in unit of c, UB = B2\/8π is the magnetic energy density, rg = γmec2\/eB is the Larmor radius, WB(k) ≈ W(k)\/2 is the magnetic component of the energy density of turbulence fields per unit of k [indicated with W(k)] and kres = 2π\/rg is the resonant wavenumber. Note that an electron with a fixed γ can interact only with Alfvén waves whose wavelength is smaller than its Larmor radius. From the time acceleration, the momentum diffusion coefficient can be obtained using Dp = p2\/2tacc. Neglecting inverse Compton and adiabatic cooling for simplicity, the cooling time is equal to:\n(3)$$\\begin{eqnarray*}\r\nt_\\text{cool} = \\frac{6 \\pi m_e c}{\\sigma _T B^2 \\gamma } ,\r\n\\end{eqnarray*}$$where B is the mean magnetic field and σT is the Thomson cross-section. From the cooling time, it is possible to calculate the cooling coefficient, in fact $t_\\text{cool} = p\/\\dot{p}$. Another effect influencing the electron spectra is the spatial escape from the acceleration site:\n(4)$$\\begin{eqnarray*}\r\nt_\\text{esc} = \\frac{R}{c} + \\frac{R^2}{k_\\parallel } ,\r\n\\end{eqnarray*}$$where k∥ = crg\/9ζ(kres) is the spatial diffusion coefficient along the mean magnetic field, while ζ(k) = kWB(k)\/UB is the relative amplitude of the turbulent magnetic field energy density for a given k. Note that if the mean free path is large (which implies a small diffusion coefficient), the escape time is simply equal to the geometric escape time, that is the ratio between the dimension of the acceleration region and the particles velocity. Finally, the last term of equation (1) describes the particle injection, identified here as the electrons accelerated at the recollimation shock and advected downstream. Supposing a strong shock, the injected electron density per unit time is equal to:\n(5)$$\\begin{eqnarray*}\r\nI_n(\\gamma) = I_{n,0} \\, \\gamma ^{-2}\\, e^{-\\frac{\\gamma }{\\gamma _\\text{cut}}} \\quad \\text{with} \\quad \\gamma _\\text{inj}\\lt \\gamma \\lt 100\\, \\gamma _\\text{cut} .\r\n\\end{eqnarray*}$$The extremes of the injection range are fixed and they are estimated thanks to recent simulations of diffusive shock acceleration: γinj = 103 and γcut = 105 (Zech & Lemoine 2021). From the injected electron density per unit time, it is possible to obtain the injection distribution in the momentum space, in fact In(γ) = 4πp2mecIf(p).","Citation Text":["Kakuwa 2016"],"Citation Start End":[[981,992]]} {"Identifier":"2021ApJ...911...21B__Gadotti_2008a_Instance_1","Paragraph":"In addition to the selection using \n\n\n\n\n\n, we filter our sample of 1083 double-component galaxies. Our aim is to select S0 galaxies for which we can reliably measure the colors of both the bulge and disk components. To this end, we exclude 68 double-component galaxies with unphysical fits:\n\n1.\nnbulge pegged at the allowed fit limits (37 galaxies) and\n\n\n2.\nre,bulge or re,disk pegged at the allowed fit limits (31 galaxies).\n\nWe also exclude 404 double-component galaxies with unresolved radial parameters:\n\n1.\nre,disk is less than 5% larger than re,bulge, since the bulge is defined as the most compact component (134 galaxies), and\n\n\n2.\nre,bulge is smaller than 80% of the PSF half-width at half-maximum in order to recover reliable bulge properties (Gadotti 2009; Meert et al. 2015; 270 galaxies).\n\nFinally, we exclude 142 double-component galaxies for which the separation of the bulge and disk measurements is unreliable:\n\n1.\nnbulge 0.6 to exclude bars, which typically have n ∼ 0.5 (Gadotti 2008a, 2008b; 33 galaxies), and\n\n\n2.\nbulge-to-total flux ratio (B\/T) lower than 0.2 and larger than 0.8 to exclude galaxies dominated by one component (Meert et al. 2015; 109 galaxies).\n\nThe filter causing the exclusion of the largest number of double-component fits is due to the impact of the PSF on the geometrical properties of the bulge, which tends to make the bulge rounder and harder to constrain. The effects of the PSF on the bulge properties have been detected in several previous works (Gadotti 2008a, 2009; Bernardi et al. 2014; Meert et al. 2015). For galaxies with double-component unphysical fits or unreliable bulge\/disk separation, the single-component fit is preferable. Galaxies with unresolved radial parameters are not useful for investigating separate bulge and disk properties, but they are still better characterized by a double-component fit. In conclusion, the number of SDSS+ATLAS single-component galaxies is 782 (47%), the number of SDSS+ATLAS reliable double-component galaxies is 469 (28%), and the number of SDSS+ATLAS double-component galaxies with unresolved radial parameters is 404 (25%). For the single-component sample, 388 galaxies are bulge-dominated with Sérsic index n > 2, and 394 are disk-dominated with Sérsic index n 2. For the reliable double-component sample, 418 galaxies are better described by the most complex Sérsic + exponential model, 37 by the simple Sérsic + exponential model, and 14 by the de Vaucouleurs + exponential model. The range in stellar mass of the 469 double-component galaxies is \n\n\n\n\n\n. The galaxies with unresolved bulge and disk radial parameters are characterized by a lower galaxy stellar mass and smaller size compared to the double-component galaxies with reliable bulge and disk measurements. The median \n\n\n\n\n\n difference is 0.145 ± 0.037 dex, and the median galaxy size difference, measured as the single-component re, is 0469 ± 0091. Thus, the exclusion of these galaxies limits our study to double-component galaxies that tend to have a large stellar mass and size for which the bulge and disk colors are reliably estimated.","Citation Text":["Gadotti 2008a"],"Citation Start End":[[991,1004]]} {"Identifier":"2021ApJ...911...21B__Gadotti_2008a_Instance_2","Paragraph":"In addition to the selection using \n\n\n\n\n\n, we filter our sample of 1083 double-component galaxies. Our aim is to select S0 galaxies for which we can reliably measure the colors of both the bulge and disk components. To this end, we exclude 68 double-component galaxies with unphysical fits:\n\n1.\nnbulge pegged at the allowed fit limits (37 galaxies) and\n\n\n2.\nre,bulge or re,disk pegged at the allowed fit limits (31 galaxies).\n\nWe also exclude 404 double-component galaxies with unresolved radial parameters:\n\n1.\nre,disk is less than 5% larger than re,bulge, since the bulge is defined as the most compact component (134 galaxies), and\n\n\n2.\nre,bulge is smaller than 80% of the PSF half-width at half-maximum in order to recover reliable bulge properties (Gadotti 2009; Meert et al. 2015; 270 galaxies).\n\nFinally, we exclude 142 double-component galaxies for which the separation of the bulge and disk measurements is unreliable:\n\n1.\nnbulge 0.6 to exclude bars, which typically have n ∼ 0.5 (Gadotti 2008a, 2008b; 33 galaxies), and\n\n\n2.\nbulge-to-total flux ratio (B\/T) lower than 0.2 and larger than 0.8 to exclude galaxies dominated by one component (Meert et al. 2015; 109 galaxies).\n\nThe filter causing the exclusion of the largest number of double-component fits is due to the impact of the PSF on the geometrical properties of the bulge, which tends to make the bulge rounder and harder to constrain. The effects of the PSF on the bulge properties have been detected in several previous works (Gadotti 2008a, 2009; Bernardi et al. 2014; Meert et al. 2015). For galaxies with double-component unphysical fits or unreliable bulge\/disk separation, the single-component fit is preferable. Galaxies with unresolved radial parameters are not useful for investigating separate bulge and disk properties, but they are still better characterized by a double-component fit. In conclusion, the number of SDSS+ATLAS single-component galaxies is 782 (47%), the number of SDSS+ATLAS reliable double-component galaxies is 469 (28%), and the number of SDSS+ATLAS double-component galaxies with unresolved radial parameters is 404 (25%). For the single-component sample, 388 galaxies are bulge-dominated with Sérsic index n > 2, and 394 are disk-dominated with Sérsic index n 2. For the reliable double-component sample, 418 galaxies are better described by the most complex Sérsic + exponential model, 37 by the simple Sérsic + exponential model, and 14 by the de Vaucouleurs + exponential model. The range in stellar mass of the 469 double-component galaxies is \n\n\n\n\n\n. The galaxies with unresolved bulge and disk radial parameters are characterized by a lower galaxy stellar mass and smaller size compared to the double-component galaxies with reliable bulge and disk measurements. The median \n\n\n\n\n\n difference is 0.145 ± 0.037 dex, and the median galaxy size difference, measured as the single-component re, is 0469 ± 0091. Thus, the exclusion of these galaxies limits our study to double-component galaxies that tend to have a large stellar mass and size for which the bulge and disk colors are reliably estimated.","Citation Text":["Gadotti 2008a"],"Citation Start End":[[1498,1511]]} {"Identifier":"2021ApJ...909...86X__Panesar_et_al._2014_Instance_1","Paragraph":"Besides sunspots, filaments are one of the most important features in studying solar magnetic fields. They are usually formed above the polarity inversion line (PIL), supported by either helically coiled or dipped magnetic fields (Gilbert et al. 2001). Therefore, filaments are representative signatures of discrete magnetic fields at large scales. Scientific observations of filaments started in the 1880s at the Arcetri Astrophysical Observatory in Florence, Italy (McIntosh et al. 2019). Thus, the long time span of the archive of filaments becomes crucial in studying the long-term variations of solar magnetic fields. Poleward and equatorward migrations of filaments have already been studied extensively, e.g., Cliver (2014), Xu et al. (2018), McIntosh et al. (2019), and Tlatova et al. (2020). Among different types of filaments (Hansen & Hansen 1975), polar crown filaments (PCFs) locate at the highest latitudes and usually reside near the polar crown cavities (Leroy et al. 1983). Their underlying PILs separate the predominate polar field of the previous cycle and the dispersed field of the current cycle, drifting poleward from the trailing polarities of sunspots or sunspot groups in lower latitudes (Tang 1987; Panesar et al. 2014). Also known as “rush-to-the-pole,” the poleward migration is an important property of PCFs and a good indicator of the polarity reversal of the solar magnetic field and the occurrence of the solar maximum (e.g., Ananthakrishnan 1952; Cliver 2014). Moreover, polar magnetic fields are difficult to measure because of the projection effect, and they are much weaker than the fields in low-latitude and active regions. Recently, Xu et al. (2018) studied the PCFs observed by the Kanzelhöhe Solar Observatory (KSO) and Big Bear Solar Observatory (BBSO) between 1973 and 2018 (cycles 21–24). Their results show the following. The poleward migration speeds of PCFs are between 0.4 and 0.7 per Carrington rotation (CR), which is about 5°–9° yr–1. This result is consistent with the speed found by Ulrich (2010) and Altrock (2014; for coronal Fe xiv emission). The tilt angles of the filaments were studied in Mazumder et al. (2018) and Diercke & Denker (2019). The authors found that the tilt angles of the filaments have opposite signs in the northern and southern solar hemispheres, as compared to the expected interactive region formation. Similar results are found in a much longer time span by Hao et al. (2015) and Tlatov et al. (2016). In addition, the asymmetric distribution of filaments in the northern and southern solar hemispheres is found to be correlated with the asymmetry of sunspot areas. More recently, McIntosh et al. (2019) studied the activity cycles near the solar equator, using a comprehensive data set going back to 1880. The authors showed that the timing of PCFs reaching the polar caps is correlated with cycle terminators, which are defined as the rapid intensity changes of extreme-UV brightenings occurring between cycles. They also suggested that PCFs are representative features in studying the polar magnetic reversal quantitatively. Tlatova et al. (2020) analyzed prominences observed in the Ca ii K line at the solar limb, starting as early as 1897 with hand drawings and digitized records after 1910. Their results show systematically higher migration speeds of PCFs than those found by Xu et al. (2018), Ulrich (2010), and Altrock (2014) but with similar variation trends. The discrepancy is likely due to several factors, such as the selection of prominences over filaments and the latitude range. Chatterjee et al. (2020) performed an automated detection of prominence latitudes from Ca ii K disk blocked images from Kodaikanal Solar Observatory (since 1906) and quantified the nonlinearity in poleward migration with its variation over 10 solar cycles combining data from KSO and Meudon Observatory in Meudon, France (Demarcq et al. 1985).","Citation Text":["Panesar et al. 2014"],"Citation Start End":[[1226,1245]]} {"Identifier":"2021ApJ...909...86XMcIntosh_et_al._2019_Instance_1","Paragraph":"Besides sunspots, filaments are one of the most important features in studying solar magnetic fields. They are usually formed above the polarity inversion line (PIL), supported by either helically coiled or dipped magnetic fields (Gilbert et al. 2001). Therefore, filaments are representative signatures of discrete magnetic fields at large scales. Scientific observations of filaments started in the 1880s at the Arcetri Astrophysical Observatory in Florence, Italy (McIntosh et al. 2019). Thus, the long time span of the archive of filaments becomes crucial in studying the long-term variations of solar magnetic fields. Poleward and equatorward migrations of filaments have already been studied extensively, e.g., Cliver (2014), Xu et al. (2018), McIntosh et al. (2019), and Tlatova et al. (2020). Among different types of filaments (Hansen & Hansen 1975), polar crown filaments (PCFs) locate at the highest latitudes and usually reside near the polar crown cavities (Leroy et al. 1983). Their underlying PILs separate the predominate polar field of the previous cycle and the dispersed field of the current cycle, drifting poleward from the trailing polarities of sunspots or sunspot groups in lower latitudes (Tang 1987; Panesar et al. 2014). Also known as “rush-to-the-pole,” the poleward migration is an important property of PCFs and a good indicator of the polarity reversal of the solar magnetic field and the occurrence of the solar maximum (e.g., Ananthakrishnan 1952; Cliver 2014). Moreover, polar magnetic fields are difficult to measure because of the projection effect, and they are much weaker than the fields in low-latitude and active regions. Recently, Xu et al. (2018) studied the PCFs observed by the Kanzelhöhe Solar Observatory (KSO) and Big Bear Solar Observatory (BBSO) between 1973 and 2018 (cycles 21–24). Their results show the following. The poleward migration speeds of PCFs are between 0.4 and 0.7 per Carrington rotation (CR), which is about 5°–9° yr–1. This result is consistent with the speed found by Ulrich (2010) and Altrock (2014; for coronal Fe xiv emission). The tilt angles of the filaments were studied in Mazumder et al. (2018) and Diercke & Denker (2019). The authors found that the tilt angles of the filaments have opposite signs in the northern and southern solar hemispheres, as compared to the expected interactive region formation. Similar results are found in a much longer time span by Hao et al. (2015) and Tlatov et al. (2016). In addition, the asymmetric distribution of filaments in the northern and southern solar hemispheres is found to be correlated with the asymmetry of sunspot areas. More recently, McIntosh et al. (2019) studied the activity cycles near the solar equator, using a comprehensive data set going back to 1880. The authors showed that the timing of PCFs reaching the polar caps is correlated with cycle terminators, which are defined as the rapid intensity changes of extreme-UV brightenings occurring between cycles. They also suggested that PCFs are representative features in studying the polar magnetic reversal quantitatively. Tlatova et al. (2020) analyzed prominences observed in the Ca ii K line at the solar limb, starting as early as 1897 with hand drawings and digitized records after 1910. Their results show systematically higher migration speeds of PCFs than those found by Xu et al. (2018), Ulrich (2010), and Altrock (2014) but with similar variation trends. The discrepancy is likely due to several factors, such as the selection of prominences over filaments and the latitude range. Chatterjee et al. (2020) performed an automated detection of prominence latitudes from Ca ii K disk blocked images from Kodaikanal Solar Observatory (since 1906) and quantified the nonlinearity in poleward migration with its variation over 10 solar cycles combining data from KSO and Meudon Observatory in Meudon, France (Demarcq et al. 1985).","Citation Text":["McIntosh et al. 2019"],"Citation Start End":[[468,488]]} {"Identifier":"2021ApJ...909...86XXu_et_al._(2018)_Instance_1","Paragraph":"Besides sunspots, filaments are one of the most important features in studying solar magnetic fields. They are usually formed above the polarity inversion line (PIL), supported by either helically coiled or dipped magnetic fields (Gilbert et al. 2001). Therefore, filaments are representative signatures of discrete magnetic fields at large scales. Scientific observations of filaments started in the 1880s at the Arcetri Astrophysical Observatory in Florence, Italy (McIntosh et al. 2019). Thus, the long time span of the archive of filaments becomes crucial in studying the long-term variations of solar magnetic fields. Poleward and equatorward migrations of filaments have already been studied extensively, e.g., Cliver (2014), Xu et al. (2018), McIntosh et al. (2019), and Tlatova et al. (2020). Among different types of filaments (Hansen & Hansen 1975), polar crown filaments (PCFs) locate at the highest latitudes and usually reside near the polar crown cavities (Leroy et al. 1983). Their underlying PILs separate the predominate polar field of the previous cycle and the dispersed field of the current cycle, drifting poleward from the trailing polarities of sunspots or sunspot groups in lower latitudes (Tang 1987; Panesar et al. 2014). Also known as “rush-to-the-pole,” the poleward migration is an important property of PCFs and a good indicator of the polarity reversal of the solar magnetic field and the occurrence of the solar maximum (e.g., Ananthakrishnan 1952; Cliver 2014). Moreover, polar magnetic fields are difficult to measure because of the projection effect, and they are much weaker than the fields in low-latitude and active regions. Recently, Xu et al. (2018) studied the PCFs observed by the Kanzelhöhe Solar Observatory (KSO) and Big Bear Solar Observatory (BBSO) between 1973 and 2018 (cycles 21–24). Their results show the following. The poleward migration speeds of PCFs are between 0.4 and 0.7 per Carrington rotation (CR), which is about 5°–9° yr–1. This result is consistent with the speed found by Ulrich (2010) and Altrock (2014; for coronal Fe xiv emission). The tilt angles of the filaments were studied in Mazumder et al. (2018) and Diercke & Denker (2019). The authors found that the tilt angles of the filaments have opposite signs in the northern and southern solar hemispheres, as compared to the expected interactive region formation. Similar results are found in a much longer time span by Hao et al. (2015) and Tlatov et al. (2016). In addition, the asymmetric distribution of filaments in the northern and southern solar hemispheres is found to be correlated with the asymmetry of sunspot areas. More recently, McIntosh et al. (2019) studied the activity cycles near the solar equator, using a comprehensive data set going back to 1880. The authors showed that the timing of PCFs reaching the polar caps is correlated with cycle terminators, which are defined as the rapid intensity changes of extreme-UV brightenings occurring between cycles. They also suggested that PCFs are representative features in studying the polar magnetic reversal quantitatively. Tlatova et al. (2020) analyzed prominences observed in the Ca ii K line at the solar limb, starting as early as 1897 with hand drawings and digitized records after 1910. Their results show systematically higher migration speeds of PCFs than those found by Xu et al. (2018), Ulrich (2010), and Altrock (2014) but with similar variation trends. The discrepancy is likely due to several factors, such as the selection of prominences over filaments and the latitude range. Chatterjee et al. (2020) performed an automated detection of prominence latitudes from Ca ii K disk blocked images from Kodaikanal Solar Observatory (since 1906) and quantified the nonlinearity in poleward migration with its variation over 10 solar cycles combining data from KSO and Meudon Observatory in Meudon, France (Demarcq et al. 1985).","Citation Text":["Xu et al. (2018)"],"Citation Start End":[[1673,1689]]} {"Identifier":"2021ApJ...909...86XTlatova_et_al._(2020)_Instance_2","Paragraph":"Besides sunspots, filaments are one of the most important features in studying solar magnetic fields. They are usually formed above the polarity inversion line (PIL), supported by either helically coiled or dipped magnetic fields (Gilbert et al. 2001). Therefore, filaments are representative signatures of discrete magnetic fields at large scales. Scientific observations of filaments started in the 1880s at the Arcetri Astrophysical Observatory in Florence, Italy (McIntosh et al. 2019). Thus, the long time span of the archive of filaments becomes crucial in studying the long-term variations of solar magnetic fields. Poleward and equatorward migrations of filaments have already been studied extensively, e.g., Cliver (2014), Xu et al. (2018), McIntosh et al. (2019), and Tlatova et al. (2020). Among different types of filaments (Hansen & Hansen 1975), polar crown filaments (PCFs) locate at the highest latitudes and usually reside near the polar crown cavities (Leroy et al. 1983). Their underlying PILs separate the predominate polar field of the previous cycle and the dispersed field of the current cycle, drifting poleward from the trailing polarities of sunspots or sunspot groups in lower latitudes (Tang 1987; Panesar et al. 2014). Also known as “rush-to-the-pole,” the poleward migration is an important property of PCFs and a good indicator of the polarity reversal of the solar magnetic field and the occurrence of the solar maximum (e.g., Ananthakrishnan 1952; Cliver 2014). Moreover, polar magnetic fields are difficult to measure because of the projection effect, and they are much weaker than the fields in low-latitude and active regions. Recently, Xu et al. (2018) studied the PCFs observed by the Kanzelhöhe Solar Observatory (KSO) and Big Bear Solar Observatory (BBSO) between 1973 and 2018 (cycles 21–24). Their results show the following. The poleward migration speeds of PCFs are between 0.4 and 0.7 per Carrington rotation (CR), which is about 5°–9° yr–1. This result is consistent with the speed found by Ulrich (2010) and Altrock (2014; for coronal Fe xiv emission). The tilt angles of the filaments were studied in Mazumder et al. (2018) and Diercke & Denker (2019). The authors found that the tilt angles of the filaments have opposite signs in the northern and southern solar hemispheres, as compared to the expected interactive region formation. Similar results are found in a much longer time span by Hao et al. (2015) and Tlatov et al. (2016). In addition, the asymmetric distribution of filaments in the northern and southern solar hemispheres is found to be correlated with the asymmetry of sunspot areas. More recently, McIntosh et al. (2019) studied the activity cycles near the solar equator, using a comprehensive data set going back to 1880. The authors showed that the timing of PCFs reaching the polar caps is correlated with cycle terminators, which are defined as the rapid intensity changes of extreme-UV brightenings occurring between cycles. They also suggested that PCFs are representative features in studying the polar magnetic reversal quantitatively. Tlatova et al. (2020) analyzed prominences observed in the Ca ii K line at the solar limb, starting as early as 1897 with hand drawings and digitized records after 1910. Their results show systematically higher migration speeds of PCFs than those found by Xu et al. (2018), Ulrich (2010), and Altrock (2014) but with similar variation trends. The discrepancy is likely due to several factors, such as the selection of prominences over filaments and the latitude range. Chatterjee et al. (2020) performed an automated detection of prominence latitudes from Ca ii K disk blocked images from Kodaikanal Solar Observatory (since 1906) and quantified the nonlinearity in poleward migration with its variation over 10 solar cycles combining data from KSO and Meudon Observatory in Meudon, France (Demarcq et al. 1985).","Citation Text":["Tlatova et al. (2020)"],"Citation Start End":[[3109,3130]]} {"Identifier":"2021ApJ...909...86XTlatova_et_al._(2020)_Instance_1","Paragraph":"Besides sunspots, filaments are one of the most important features in studying solar magnetic fields. They are usually formed above the polarity inversion line (PIL), supported by either helically coiled or dipped magnetic fields (Gilbert et al. 2001). Therefore, filaments are representative signatures of discrete magnetic fields at large scales. Scientific observations of filaments started in the 1880s at the Arcetri Astrophysical Observatory in Florence, Italy (McIntosh et al. 2019). Thus, the long time span of the archive of filaments becomes crucial in studying the long-term variations of solar magnetic fields. Poleward and equatorward migrations of filaments have already been studied extensively, e.g., Cliver (2014), Xu et al. (2018), McIntosh et al. (2019), and Tlatova et al. (2020). Among different types of filaments (Hansen & Hansen 1975), polar crown filaments (PCFs) locate at the highest latitudes and usually reside near the polar crown cavities (Leroy et al. 1983). Their underlying PILs separate the predominate polar field of the previous cycle and the dispersed field of the current cycle, drifting poleward from the trailing polarities of sunspots or sunspot groups in lower latitudes (Tang 1987; Panesar et al. 2014). Also known as “rush-to-the-pole,” the poleward migration is an important property of PCFs and a good indicator of the polarity reversal of the solar magnetic field and the occurrence of the solar maximum (e.g., Ananthakrishnan 1952; Cliver 2014). Moreover, polar magnetic fields are difficult to measure because of the projection effect, and they are much weaker than the fields in low-latitude and active regions. Recently, Xu et al. (2018) studied the PCFs observed by the Kanzelhöhe Solar Observatory (KSO) and Big Bear Solar Observatory (BBSO) between 1973 and 2018 (cycles 21–24). Their results show the following. The poleward migration speeds of PCFs are between 0.4 and 0.7 per Carrington rotation (CR), which is about 5°–9° yr–1. This result is consistent with the speed found by Ulrich (2010) and Altrock (2014; for coronal Fe xiv emission). The tilt angles of the filaments were studied in Mazumder et al. (2018) and Diercke & Denker (2019). The authors found that the tilt angles of the filaments have opposite signs in the northern and southern solar hemispheres, as compared to the expected interactive region formation. Similar results are found in a much longer time span by Hao et al. (2015) and Tlatov et al. (2016). In addition, the asymmetric distribution of filaments in the northern and southern solar hemispheres is found to be correlated with the asymmetry of sunspot areas. More recently, McIntosh et al. (2019) studied the activity cycles near the solar equator, using a comprehensive data set going back to 1880. The authors showed that the timing of PCFs reaching the polar caps is correlated with cycle terminators, which are defined as the rapid intensity changes of extreme-UV brightenings occurring between cycles. They also suggested that PCFs are representative features in studying the polar magnetic reversal quantitatively. Tlatova et al. (2020) analyzed prominences observed in the Ca ii K line at the solar limb, starting as early as 1897 with hand drawings and digitized records after 1910. Their results show systematically higher migration speeds of PCFs than those found by Xu et al. (2018), Ulrich (2010), and Altrock (2014) but with similar variation trends. The discrepancy is likely due to several factors, such as the selection of prominences over filaments and the latitude range. Chatterjee et al. (2020) performed an automated detection of prominence latitudes from Ca ii K disk blocked images from Kodaikanal Solar Observatory (since 1906) and quantified the nonlinearity in poleward migration with its variation over 10 solar cycles combining data from KSO and Meudon Observatory in Meudon, France (Demarcq et al. 1985).","Citation Text":["Tlatova et al. (2020)"],"Citation Start End":[[778,799]]} {"Identifier":"2021ApJ...908...84V__Kleban_&_Schillo_2012_Instance_1","Paragraph":"The importance of obtaining high-fidelity constraints on ΩK cannot be overstated. The sign and value of ΩK play an important role in determining the future evolution of the universe. From the model-building side, constraints on ΩK have important consequences for models of inflation, most of which predict an universe that is spatially flat to the level of \n\n\n\n\n\n (see, e.g., Kazanas 1980; Starobinsky 1980; Guth 1981; Mukhanov & Chibisov 1981; Sato 1981; Albrecht & Steinhardt 1982; Linde 1982). Conversely, detecting ∣ΩK∣ ≠ 0 at the \n\n\n\n\n\n level or larger could be a problem for most models of inflation (Linde 2008; Guth & Nomura 2012; Kleban & Schillo 2012), although others (see, e.g., Bull & Kamionkowski 2013) have argued that this might not be as problematic. It is generally simpler to construct inflationary models in a spatially open universe (see, e.g., Coleman & De Luccia 1980; Gott 1982; Ratra 1994; Ratra & Peebles 1995, 1994; Bucher et al. 1995; Linde 1995; Yamamoto et al. 1995; Linde 2008; Guth & Nomura 2012; Kleban & Schillo 2012), whereas achieving the same result in a spatially closed universe might require more fine-tuning (see, e.g., Ratra 1985; Hartle & Hawking 1987; Linde 2003; Ratra 2017). In any case, the importance of spatial curvature in modern cosmology is the reason why a huge number of works have been devoted to providing and forecasting constraints on ΩK from current and future cosmological observations.6\n\n6\nFor an inevitably incomplete list of such works, see, e.g., Vardanyan et al. (2009), Carbone et al. (2011), Li & Zhang (2012), Bull et al. (2015), Takada & Dore (2015), Di Dio et al. (2016), Leonard et al. (2016), Rana et al. (2017), Ooba et al. (2018a), Jimenez et al. (2018), Ooba et al. (2018b), Park & Ratra (2018, 2019a, 2019b, 2019c, 2020), Denissenya et al. (2018), Bernal et al. (2019), Li et al. (2020), Wang et al. (2020), Zhai et al. (2020), Geng et al. (2020), Heinesen & Buchert (2020), Gao et al. (2020), Khadka & Ratra (2020), Nunes & Bernui (2020), Liu et al. (2020), Chudaykin et al. (2021), Benisty & Staicova (2020), Shimon & Rephaeli (2020), Tröster et al. (2020), Di Valentino et al. (2021), and Qi et al. (2020).\n\n","Citation Text":["Kleban & Schillo 2012","Kleban & Schillo 2012"],"Citation Start End":[[639,660],[1029,1050]]} {"Identifier":"2018AandA...620A..31M__Kuiper_&_Yorke_2013_Instance_1","Paragraph":"Any massive stellar source from ~8 M⊙ can burn hot enough to completely ionise the surrounding molecular material to form an H II region (Wood & Churchwell 1989; Churchwell 1990; Kurtz 2005) and destroy any complex chemical tracers that are traditionally used to understand the kinematics of their natal environments and their accretion discs. Initial arguments by Walmsley (1995) argued that high accretion rates will cause a very dense H II region that is optically thick to radio emission and thus the H II would not be seen. However, for heavily accreting massive YSOs the onset of the H II region could be delayed via stellar bloating (Palla & Stahler 1992; Hosokawa & Omukai 2009; Hosokawa et al. 2010; Kuiper & Yorke 2013) where the effective temperature of the star is much cooler than it would be considering a main sequence star of the same luminosity. In these models, a halt or considerable reduction in accretion (≪10−3 M⊙ yr−1), or growth beyond ~30−40 M⊙, will result in the YSO contracting to a “main-sequence” configuration, heating significantly, and being able to create an H II region. The fine details of this transition are still somewhat unclear since they depend on the assumed accretion law and the initial conditions chosen for the stellar evolution calculations (Haemmerlé & Peters 2016). Observations in the infra-red (IR) have been made in search of cool stellar atmospheres that point to bloated stars, however these studies remain inconclusive (Linz et al. 2009; Testi et al. 2010). Alternative scenarios are that H II regions can be gravitationally trapped at very early ionisation stages (see Keto 2003, 2007), or flicker due to chaotic shielding of the ionising radiation by an accretion flow, leading to a non-monotonous expansion (Peters et al. 2010b). Hyper Compact (HC) H II regions (0.03 pc) are thought to be the earliest ionisation stage and therefore could relate to the halt of accretion, be a marker of a transition phase.","Citation Text":["Kuiper & Yorke 2013"],"Citation Start End":[[709,728]]} {"Identifier":"2018AandA...620A..3Haemmerlé_&_Peters_2016_Instance_1","Paragraph":"Any massive stellar source from ~8 M⊙ can burn hot enough to completely ionise the surrounding molecular material to form an H II region (Wood & Churchwell 1989; Churchwell 1990; Kurtz 2005) and destroy any complex chemical tracers that are traditionally used to understand the kinematics of their natal environments and their accretion discs. Initial arguments by Walmsley (1995) argued that high accretion rates will cause a very dense H II region that is optically thick to radio emission and thus the H II would not be seen. However, for heavily accreting massive YSOs the onset of the H II region could be delayed via stellar bloating (Palla & Stahler 1992; Hosokawa & Omukai 2009; Hosokawa et al. 2010; Kuiper & Yorke 2013) where the effective temperature of the star is much cooler than it would be considering a main sequence star of the same luminosity. In these models, a halt or considerable reduction in accretion (≪10−3 M⊙ yr−1), or growth beyond ~30−40 M⊙, will result in the YSO contracting to a “main-sequence” configuration, heating significantly, and being able to create an H II region. The fine details of this transition are still somewhat unclear since they depend on the assumed accretion law and the initial conditions chosen for the stellar evolution calculations (Haemmerlé & Peters 2016). Observations in the infra-red (IR) have been made in search of cool stellar atmospheres that point to bloated stars, however these studies remain inconclusive (Linz et al. 2009; Testi et al. 2010). Alternative scenarios are that H II regions can be gravitationally trapped at very early ionisation stages (see Keto 2003, 2007), or flicker due to chaotic shielding of the ionising radiation by an accretion flow, leading to a non-monotonous expansion (Peters et al. 2010b). Hyper Compact (HC) H II regions (0.03 pc) are thought to be the earliest ionisation stage and therefore could relate to the halt of accretion, be a marker of a transition phase.","Citation Text":["Haemmerlé & Peters 2016"],"Citation Start End":[[1290,1313]]} {"Identifier":"2018AandA...620A..3Testi_et_al._2010_Instance_1","Paragraph":"Any massive stellar source from ~8 M⊙ can burn hot enough to completely ionise the surrounding molecular material to form an H II region (Wood & Churchwell 1989; Churchwell 1990; Kurtz 2005) and destroy any complex chemical tracers that are traditionally used to understand the kinematics of their natal environments and their accretion discs. Initial arguments by Walmsley (1995) argued that high accretion rates will cause a very dense H II region that is optically thick to radio emission and thus the H II would not be seen. However, for heavily accreting massive YSOs the onset of the H II region could be delayed via stellar bloating (Palla & Stahler 1992; Hosokawa & Omukai 2009; Hosokawa et al. 2010; Kuiper & Yorke 2013) where the effective temperature of the star is much cooler than it would be considering a main sequence star of the same luminosity. In these models, a halt or considerable reduction in accretion (≪10−3 M⊙ yr−1), or growth beyond ~30−40 M⊙, will result in the YSO contracting to a “main-sequence” configuration, heating significantly, and being able to create an H II region. The fine details of this transition are still somewhat unclear since they depend on the assumed accretion law and the initial conditions chosen for the stellar evolution calculations (Haemmerlé & Peters 2016). Observations in the infra-red (IR) have been made in search of cool stellar atmospheres that point to bloated stars, however these studies remain inconclusive (Linz et al. 2009; Testi et al. 2010). Alternative scenarios are that H II regions can be gravitationally trapped at very early ionisation stages (see Keto 2003, 2007), or flicker due to chaotic shielding of the ionising radiation by an accretion flow, leading to a non-monotonous expansion (Peters et al. 2010b). Hyper Compact (HC) H II regions (0.03 pc) are thought to be the earliest ionisation stage and therefore could relate to the halt of accretion, be a marker of a transition phase.","Citation Text":["Testi et al. 2010"],"Citation Start End":[[1494,1511]]} {"Identifier":"2022MNRAS.511.3113H__Rivero-González_et_al._2011_Instance_1","Paragraph":"Abundances are estimated by fitting the different ions in the observed spectrum. Microturbulence is again fixed at 20 $\\rm km\\, s^{-1}$ for all elements, the same value adopted for the Si ionization balance. All abundances are given by number and were initially adopted to be solar and then modified to reach a better fit to the observed spectrum. Most He  lines are well fitted with a solar abundance, but the strong He i 4471 Å line points to a slightly enriched He abundance, which is consistent with the detection of He ii 4686. Thus, we adopt $\\epsilon = N({\\rm He})\/[N({\\rm H})+N({\\rm He})] =0.12\\pm 0.04$, a mildly enriched He  abundance, but still consistent with the solar one. The N abundance is poorly constrained, as the N iii lines around 4630–4640 are blended with O and C and are highly sensitive to wind details (see Rivero-González et al. 2011), whereas the N ii lines from 5666 to 5710, clear in this spectral type, are outside the spectral range of our observations. Thus, we have to rely on the very weak N ii 5005.15 and 5007.33 Å lines (a blend in our spectrum). These lines are consistent with a solar N abundance. The absence of N ii 4630.54 and N iii 4634.13 (which should be present if the N abundance is higher than solar) is also consistent with a solar N abundance. Taking into account the uncertainties in stellar parameters, we determine a value of log(N\/H) + 12 = 7.83 ± 0.15 (with 7.83 ± 0.05 being the solar value from Asplund et al. 2009). The abundance of C  relies on the C ii λ4267 line, which is weak. Unfortunately, the C ii 6578-83 lines are not well reproduced by our model. We estimate a C  abundance of log(C\/H) + 12 = 8.13$^{+0.20}_{-0.25}$, a factor of 2 below solar, where errors have again been obtained by fitting the line with varying stellar parameters. However, given the uncertainties, the line weakness and the moderate S\/N in the region, we cannot completely rule out a solar abundance. For Mg we have only the doublet line at λ4481, which fits at a slightly lower than solar abundance, but fully compatible with solar – we obtain log(Mg\/H) + 12 = 7.53 ± 0.15 – where the relatively low uncertainty is probably an underestimate as we have only one line available. On the contrary, for O and Si we have several lines and thus the same uncertainty of 0.15 dex is more representative. We obtain in both cases solar abundances, with uncertainties determined by varying the stellar parameters (except the microturbulence, which we kept fixed through the whole analysis). Abundances are given in Table 3.","Citation Text":["Rivero-González et al. 2011"],"Citation Start End":[[835,862]]} {"Identifier":"2020MNRAS.499.2912F__Schneider,_Ehlers_&_Falco_1992_Instance_1","Paragraph":"A gravitational lens deflects light from background sources depending on their projected distance R in the lens plane. The deflection angle $\\hat{\\alpha }(R)$ of a thin axially symmetric lens where the distances between the source, the lens, and the observer are much larger than the size of the lens is directly related to its cumulative mass $\\mathcal {M}(R)$ through\n(35)$$\\begin{eqnarray*}\r\n\\hat{\\alpha }(R) = \\frac{4 G\\mathcal {M}(R)}{c^2 R}\r\n\\end{eqnarray*}$$(Schneider, Ehlers & Falco 1992, equation 8.5), c being here the speed of light. Introducing DL, DS, and DLS the angular distances respectively between the observer and the lens, between the observer and the source, and between the lens and the source, one can express the scaled deflection angle\n(36)$$\\begin{eqnarray*}\r\n\\alpha (R)\\equiv \\frac{D_{\\rm L}D_{\\rm LS}}{r_\\mathrm{ c} D_{\\rm S}} \\hat{\\alpha }(R)\r\n\\end{eqnarray*}$$and the convergence\n(37)$$\\begin{eqnarray*}\r\n\\kappa (R) \\equiv \\frac{{\\Sigma }(R)}{\\Sigma _{\\rm crit}}\r\n\\end{eqnarray*}$$where distances in the lens plane are scaled in units of rc and Σcrit = c2DS\/4πGDLDLS is the lensing critical surface density. Introducing $\\widetilde{\\kappa _0} \\equiv \\widetilde{\\Sigma }(0)\/\\Sigma _{\\rm crit}$ with equation (29) and $\\mathcal {B}(a,b)=\\Gamma (a)\\Gamma (b)\/\\Gamma (a+b)$, the scaled deflection angle for an untruncated DZ profile yields\n(38)$$\\begin{eqnarray*}\r\n\\widetilde{\\alpha }(X) = \\frac{\\sqrt{\\pi } ~\\widetilde{\\kappa _0} }{\\Gamma (2-2a)\\Gamma (5)} X^2~ H_{3,3}^{2,2} \\left[ \\left. \\begin{array}{c}(-6,4), (-\\frac{1}{2},1), (0,1)\\\\\r\n(-\\frac{1}{2},1), (-2a,4), (-\\frac{3}{2}, 1) \\end{array} \\right| X^2 \\right], \\nonumber \\\\\r\n\\end{eqnarray*}$$which has a series expansion analogous to that of $\\widetilde{\\mathcal {M}}(X)$. For a DZ profile truncated at the virial radius, $\\alpha (X) = \\widetilde{\\alpha }(X)-X \\widetilde{\\Sigma }(c)\/ \\Sigma _{\\rm crit}$. We give analytic expressions for the lensing potential in Appendix F (Supporting Information).","Citation Text":["Schneider, Ehlers & Falco 1992"],"Citation Start End":[[466,496]]} {"Identifier":"2022ApJ...924...39M__Rodriguez_et_al._2019_Instance_1","Paragraph":"Stars with masses 130 M\n⊙ ≲ M\nZAMS ≲ 250 M\n⊙ are subject to the pair instability, which disrupts them completely, and hence no BH forms. Stars with M\nZAMS ≳ 250 M\n⊙ can collapse directly to IMBHs with a mass ≳135 M\n⊙. Thus, in the standard picture, there should be an upper stellar-mass BH gap in the range [65, 135] M\n⊙, and any BHs observed in this range (e.g., the primary BH of GW190521) have to form via other formation channels—for example, through hierarchical coalescence of smaller BHs or direct collapse of a stellar merger between an evolved star and a main-sequence companion (e.g., Quinlan & Shapiro 1989; Portegies Zwart & McMillan 2000; Ebisuzaki et al. 2001; Miller & Hamilton 2002; O’Leary et al. 2006; Gerosa & Berti 2017; Antonini et al. 2019; Di Carlo et al. 2019, 2020; Rodriguez et al. 2019; Gayathri et al. 2020a; Kimball et al. 2021; Mapelli et al. 2021). However, the exact mass boundaries of the gap depend on parameters that are uncertain. For example, the 12C(α, γ)16O nuclear reaction rate, which converts carbon to oxygen in the core, can affect the boundary significantly (Takahashi 2018; Farmer et al. 2020; Costa et al. 2021; Woosley & Heger 2021). Here, to better determine whether future GW observations will be able to observe BHs in the mass gap, we recompute the mass-gap boundaries with updated 12C(α, γ)16O reaction rates and increased mass and temporal resolution. The complexity of this system has made a reliable analysis of the reaction a decades-old challenge.\n7\n\n\n7\nThe reaction rate for 12C(α, γ)16O is determined by the quantum structure of the compound nucleus 16O as an α cluster system. It is characterized by the interfering ℓ = 1 waves of the J\n\nπ\n = 1− resonances and sub-threshold levels defining an E1 component for the reaction cross section as well as by the ℓ = 2 components and interference from broad J\n\nπ\n = 2+ resonances and the nonresonant E2 external capture to the ground state of 16O. In addition to these two main E1 and E2 ground-state components, transitions to higher lying excited states occur that also add to the total cross section (see, e.g., Buchmann & Barnes 2006; deBoer et al. 2017). The rapidly declining cross section at low energies has prohibited a direct measurement of the reaction at stellar temperatures, and the reaction rate is entirely based on the theoretical analysis and extrapolation of the experimental data toward lower energies. The rate newly derived by deBoer et al. (2017), using a multichannel analysis approach, derives for the first time a reliable prediction for the interference patterns within the reaction components by taking into account all available experimental data sets that cover the near-threshold energy range of the 12C(α, γ)16O process.","Citation Text":["Rodriguez et al. 2019"],"Citation Start End":[[791,812]]} {"Identifier":"2017ApJ...849L..16I__Bernardi_et_al._2003_Instance_1","Paragraph":"We gathered four independent measurements of \n\n\n\n\n\n from the literature: 2.312 ± 0.095 (Carter et al. 1988), 2.237 ± 0.013 (Beuing et al. 2002), 2.292 ± 0.0429\n\n9\nWegner et al. (2003) listed a value within a 0.595 \n\n\n\n\n\n kpc radius aperture, and this value is converted to the value for an aperture with 1\/8 of \n\n\n\n\n\n using Equation (1) of Cappellari et al. (2006).\n (Wegner et al. 2003), and 2.212 ± 0.045 (Ogando et al. 2008). We adopt a weighted mean value, \n\n\n\n\n\n, of the four independent measurements. Using the \n\n\n\n\n\n values from Table 1 after applying the Galactic extinction correction and the FP coefficients from various sources, we derive distances to NGC 4993 in seven different bands. Table 3 summarizes the result. In total, 17 different estimates are derived. Two of the FP relations are based on \n\n\n\n\n\n, and z (Bernardi et al. 2003; La Barbera et al. 2010), and for these cases, the \n\n\n\n\n\n, and I values are converted to \n\n\n\n\n\n, and i values while keeping the structural parameters in the corresponding bands. Uncertainties in the distances are dominated by the intrinsic dispersion in the FP relation, which has errors of about 7 to 12 Mpc (or 23% of the derived value; e.g., Bernardi et al. 2003). The errors from the observed quantities amount to only ≲10% of the FP distance, and we ignore them. The uncertainty in the Hubble constant is only a few percent or less according to recent estimates (e.g., Riess et al. 2016) and also can be neglected. We note that the rms dispersion of the 17 estimates is 5.3 Mpc, smaller than the FP distance error of each estimate. This suggests that the 17 estimates are not independent quantities (e.g., they share a \n\n\n\n\n\n value and are based on an identical object), and the rms dispersion of 5.3 Mpc is an uncertainty related to the wavelength and the adopted FP relation parameters for each measurement. Therefore, we consider a typical intrinsic scatter in the FP relation along \n\n\n\n\n\n of 0.09 dex (23% of the value) as our distance error. Considering these factors, we adopt 37.7 ± 8.7 \n\n\n\n\n\n Mpc as the FP-based distance. Note that this is an angular diameter distance, and at z = 0.009783 of NGC 4993 (Levan et al. 2017), the luminosity distance is 2% larger at 38.4 ± 8.9 \n\n\n\n\n\n Mpc. We also note that the mean angular diameter distance of 37.7 Mpc is accurate to about \n\n\n\n\n\n Mpc in regard to uncertainties due to wavelengths and FP parameter sets.","Citation Text":["Bernardi et al. 2003"],"Citation Start End":[[827,847]]} {"Identifier":"2017ApJ...849L..16I__Bernardi_et_al._2003_Instance_2","Paragraph":"We gathered four independent measurements of \n\n\n\n\n\n from the literature: 2.312 ± 0.095 (Carter et al. 1988), 2.237 ± 0.013 (Beuing et al. 2002), 2.292 ± 0.0429\n\n9\nWegner et al. (2003) listed a value within a 0.595 \n\n\n\n\n\n kpc radius aperture, and this value is converted to the value for an aperture with 1\/8 of \n\n\n\n\n\n using Equation (1) of Cappellari et al. (2006).\n (Wegner et al. 2003), and 2.212 ± 0.045 (Ogando et al. 2008). We adopt a weighted mean value, \n\n\n\n\n\n, of the four independent measurements. Using the \n\n\n\n\n\n values from Table 1 after applying the Galactic extinction correction and the FP coefficients from various sources, we derive distances to NGC 4993 in seven different bands. Table 3 summarizes the result. In total, 17 different estimates are derived. Two of the FP relations are based on \n\n\n\n\n\n, and z (Bernardi et al. 2003; La Barbera et al. 2010), and for these cases, the \n\n\n\n\n\n, and I values are converted to \n\n\n\n\n\n, and i values while keeping the structural parameters in the corresponding bands. Uncertainties in the distances are dominated by the intrinsic dispersion in the FP relation, which has errors of about 7 to 12 Mpc (or 23% of the derived value; e.g., Bernardi et al. 2003). The errors from the observed quantities amount to only ≲10% of the FP distance, and we ignore them. The uncertainty in the Hubble constant is only a few percent or less according to recent estimates (e.g., Riess et al. 2016) and also can be neglected. We note that the rms dispersion of the 17 estimates is 5.3 Mpc, smaller than the FP distance error of each estimate. This suggests that the 17 estimates are not independent quantities (e.g., they share a \n\n\n\n\n\n value and are based on an identical object), and the rms dispersion of 5.3 Mpc is an uncertainty related to the wavelength and the adopted FP relation parameters for each measurement. Therefore, we consider a typical intrinsic scatter in the FP relation along \n\n\n\n\n\n of 0.09 dex (23% of the value) as our distance error. Considering these factors, we adopt 37.7 ± 8.7 \n\n\n\n\n\n Mpc as the FP-based distance. Note that this is an angular diameter distance, and at z = 0.009783 of NGC 4993 (Levan et al. 2017), the luminosity distance is 2% larger at 38.4 ± 8.9 \n\n\n\n\n\n Mpc. We also note that the mean angular diameter distance of 37.7 Mpc is accurate to about \n\n\n\n\n\n Mpc in regard to uncertainties due to wavelengths and FP parameter sets.","Citation Text":["Bernardi et al. 2003"],"Citation Start End":[[1193,1213]]} {"Identifier":"2019ApJ...871L..22W__Torrence_&_Compo_1998_Instance_1","Paragraph":"For the transition range around ion scales, the turbulent energy is believed to further cascade and the kinetic physics begins (Alexandrova et al. 2013; Kiyani et al. 2015). Various forms of coherent structures (i.e., current sheet, vortex filaments) are usually found to reside near this range (i.e., between the end of the MHD range and proton scales in Lion et al. 2016; Perrone et al. 2016, 2017). Hence, in the following analysis we focus on fluctuations of similar scales, where the frequency ranges is chosen as [0.4, 3] Hz, and the timescale is [0.3, 3] s. It has been shown recently that, in case of a collisionless turbulent system as the solar wind, the intermittency, non-Gaussian fluctuations, and phase coherence of magnetic field components are interrelated (Perrone et al. 2017). We expect this relation to be present here and thus take similar procedures as in Perrone et al. (2017) to search for the intermittent events. The first step is to reconstruct the fluctuations using the bandpass filter based on wavelet transforms (Torrence & Compo 1998; He et al. 2012; Wang et al. 2014; Perrone et al. 2016). The magnetic field fluctuations are thus defined as\n1\n\n\n\n\n\nwhere i represent the magnetic field components, j represent the scale index, \n\n\n\n\n\n is the constant scales step, \n\n\n\n\n\n is the real part of the wavelet coefficient \n\n\n\n\n\n, Cδ = 0.776. \n\n\n\n\n\n is the Morlet mother function and \n\n\n\n\n\n at time t = 0 (Torrence & Compo 1998), \n\n\n\n\n\n and \n\n\n\n\n\n are taken to be 0.3 and 3 s, respectively. The second step is to determine the threshold energy as defined by \n\n\n\n\n\n, where \n\n\n\n\n\n is the standard deviation of the Gaussian fit for each magnetic field fluctuation component. \n\n\n\n\n\n are fitted to be 0.36, 0.32, and 0.49 nT, leading to a \n\n\n\n\n\n ∼ 4.3 nT2. From a statistical point of view, 99.7% of all the values in Gaussian distribution are within \n\n\n\n\n\n from the mean. In other words, the events whose total energy \n\n\n\n\n\n are larger than \n\n\n\n\n\n could contribute to the non-Gaussian part of the distributions. Figure 1(e) presents the PDFs of the normalized magnetic field fluctuations \n\n\n\n\n\n together with their Gaussian fits. The presence of clear non-Gaussian tails suggest the abundance of intermittent events during the whole interval. The last step is to locate these events. As seen in Figure 1(b), there are approximately 14 events (with at least 10 s in duration) with \n\n\n\n\n\n larger than 5 nT2. We have picked one interval during 10:59:41.5–10:59:48.5 UT for further study. This event is characterized by large magnetic energy ∼150 nT2 and strong flow vorticity up to ∼1.4 \/s as compared to the mean value of ∼0.4 \/s. Furthermore, the local intermittency measure (LIM) exhibits an extension of temporal scale from several tens of seconds to sub-seconds, as seen in the LIMtotal of Figure 1(c). The LIM spectrogram, as a function of time and scales, is computed as the instantaneous energy of fluctuations normalized to its mean value over the studied time interval (Farge 1992):\n2\n\n\n\n\n\nwhere \n\n\n\n\n\n is the total fluctuation energy. For the coherent structures (space or time localized energetic events), one of its intrinsic properties is the energy coupling over many scales (Farge 1992; Frisch 1995), which is usually manifested in the spanning of LIM at a wide range of spatial scales (or temporal scales if the Taylor frozen-in hypothesis is assumed; Lion et al. 2016; Perrone et al. 2017). While for the wave phenomenon, the energy distribution is typically focused around a certain frequency, i.e., Alfvén ion cyclotron (Alexandrova et al. 2004) or electron cyclotron waves (Lacombe et al. 2014). Therefore, the extension of LIM provides evidence of coupling from MHD to sub-ion scales and hence implies the presence of a coherent structure (Farge 1992; Frisch 1995; Lion et al. 2016; Perrone et al. 2017). Note that because \n\n\n\n\n\n, \n\n\n\n\n\n, and LIMtotal exhibit nearly the same features in this event, only LIMtotal is presented here.","Citation Text":["Torrence & Compo 1998"],"Citation Start End":[[1044,1065]]} {"Identifier":"2019ApJ...871L..22W__Torrence_&_Compo_1998_Instance_2","Paragraph":"For the transition range around ion scales, the turbulent energy is believed to further cascade and the kinetic physics begins (Alexandrova et al. 2013; Kiyani et al. 2015). Various forms of coherent structures (i.e., current sheet, vortex filaments) are usually found to reside near this range (i.e., between the end of the MHD range and proton scales in Lion et al. 2016; Perrone et al. 2016, 2017). Hence, in the following analysis we focus on fluctuations of similar scales, where the frequency ranges is chosen as [0.4, 3] Hz, and the timescale is [0.3, 3] s. It has been shown recently that, in case of a collisionless turbulent system as the solar wind, the intermittency, non-Gaussian fluctuations, and phase coherence of magnetic field components are interrelated (Perrone et al. 2017). We expect this relation to be present here and thus take similar procedures as in Perrone et al. (2017) to search for the intermittent events. The first step is to reconstruct the fluctuations using the bandpass filter based on wavelet transforms (Torrence & Compo 1998; He et al. 2012; Wang et al. 2014; Perrone et al. 2016). The magnetic field fluctuations are thus defined as\n1\n\n\n\n\n\nwhere i represent the magnetic field components, j represent the scale index, \n\n\n\n\n\n is the constant scales step, \n\n\n\n\n\n is the real part of the wavelet coefficient \n\n\n\n\n\n, Cδ = 0.776. \n\n\n\n\n\n is the Morlet mother function and \n\n\n\n\n\n at time t = 0 (Torrence & Compo 1998), \n\n\n\n\n\n and \n\n\n\n\n\n are taken to be 0.3 and 3 s, respectively. The second step is to determine the threshold energy as defined by \n\n\n\n\n\n, where \n\n\n\n\n\n is the standard deviation of the Gaussian fit for each magnetic field fluctuation component. \n\n\n\n\n\n are fitted to be 0.36, 0.32, and 0.49 nT, leading to a \n\n\n\n\n\n ∼ 4.3 nT2. From a statistical point of view, 99.7% of all the values in Gaussian distribution are within \n\n\n\n\n\n from the mean. In other words, the events whose total energy \n\n\n\n\n\n are larger than \n\n\n\n\n\n could contribute to the non-Gaussian part of the distributions. Figure 1(e) presents the PDFs of the normalized magnetic field fluctuations \n\n\n\n\n\n together with their Gaussian fits. The presence of clear non-Gaussian tails suggest the abundance of intermittent events during the whole interval. The last step is to locate these events. As seen in Figure 1(b), there are approximately 14 events (with at least 10 s in duration) with \n\n\n\n\n\n larger than 5 nT2. We have picked one interval during 10:59:41.5–10:59:48.5 UT for further study. This event is characterized by large magnetic energy ∼150 nT2 and strong flow vorticity up to ∼1.4 \/s as compared to the mean value of ∼0.4 \/s. Furthermore, the local intermittency measure (LIM) exhibits an extension of temporal scale from several tens of seconds to sub-seconds, as seen in the LIMtotal of Figure 1(c). The LIM spectrogram, as a function of time and scales, is computed as the instantaneous energy of fluctuations normalized to its mean value over the studied time interval (Farge 1992):\n2\n\n\n\n\n\nwhere \n\n\n\n\n\n is the total fluctuation energy. For the coherent structures (space or time localized energetic events), one of its intrinsic properties is the energy coupling over many scales (Farge 1992; Frisch 1995), which is usually manifested in the spanning of LIM at a wide range of spatial scales (or temporal scales if the Taylor frozen-in hypothesis is assumed; Lion et al. 2016; Perrone et al. 2017). While for the wave phenomenon, the energy distribution is typically focused around a certain frequency, i.e., Alfvén ion cyclotron (Alexandrova et al. 2004) or electron cyclotron waves (Lacombe et al. 2014). Therefore, the extension of LIM provides evidence of coupling from MHD to sub-ion scales and hence implies the presence of a coherent structure (Farge 1992; Frisch 1995; Lion et al. 2016; Perrone et al. 2017). Note that because \n\n\n\n\n\n, \n\n\n\n\n\n, and LIMtotal exhibit nearly the same features in this event, only LIMtotal is presented here.","Citation Text":["Torrence & Compo 1998"],"Citation Start End":[[1430,1451]]} {"Identifier":"2019MNRAS.486..570T__Harrington_1968_Instance_1","Paragraph":"A triple system consists of an inner binary with masses m1 and m2 (defined as m1 ≥ m2), and a third object with mass m3 (in our case, the third object is always the central SMBH). It is convenient to describe the orbit using Jacobi coordinates (see e.g. Murray & Dermott 2000, p. 441). In this treatment, the dominant motion of the triple system can be divided into two separate Keplerian orbits: one is the motion of objects 1 and 2 relative to each other, and the other one is the motion of object 3 relative to the centre of mass of the inner binary. We denote the relative position vectors, semimajor axes, and eccentricities of these systems by $\\boldsymbol {r}_1$ and $\\boldsymbol {r}_2$, a1 and a2, and e1 and e2, respectively. If the third object is sufficiently distant from the inner binary, a perturbative approach can be used to describe the evolution of the system. In the usual secular approximation (e.g. Marchal 1990), the two orbits exchange angular momentum, but not energy. Hence, the eccentricities and orientations of the orbits can change, but the semimajor axes cannot. The coupling term in the Hamiltonian can be written in a power series expansion of parameter α = a1\/a2 (see e.g. Harrington 1968), where the Hamiltonian is\n(16)\r\n\\begin{eqnarray*}\r\n\\mathcal {H} &=&\\, \\frac{m_1 m_2}{2a_1} + \\frac{(m_1+m_2)m_3}{2a_2} \\nonumber \\\\\r\n&&+\\, \\frac{1}{a_2} \\sum \\limits _{j=2}^{\\infty } \\alpha ^j M_\\mathrm{ j} \\left(\\frac{r_1}{a_1} \\right)^j \\left(\\frac{a_2}{r_2} \\right)^{j+1} P_\\mathrm{ j}(\\mathrm{cos}\\Phi) ,\r\n\\end{eqnarray*}\r\nPj is the jth-degree Legendre polynomial, Φ is the angle between $\\boldsymbol {r}_1$ and $\\boldsymbol {r}_2$, and\n(17)\r\n\\begin{eqnarray*}\r\nM_\\mathrm{ j} = m_1 m_2 m_3 \\frac{m_1^{j-1}+(-1)^j(m_2)^{j-1}}{(m_1+m_2)^j} .\r\n\\end{eqnarray*}\r\nWhen analysing these hierarchical triple systems, it is particularly convenient to adopt the canonical coordinates known as Delaunay’s elements (e.g. Valtonen & Karttunen 2006). The coordinates are the mean anomalies, l1 and l2, the longitudes of ascending nodes, h1 and h2, and the arguments of periastron, g1 and g2. One can then eliminate the short-period terms by a canonical transformation to get equations that describe the long-term evolution of the triple system. This technique is known as the Von Zeipel transformation (see e.g. Brouwer 1959). Naoz et al. (2013a) showed that going beyond the quadrupole-order approximation is necessary in order to acquire highly eccentric Kozai excitations. They also pointed out a common mistake in the Hamiltonian treatment of these hierarchical systems in previous studies, which could lead to erroneous conclusions in the test particle limit. The full octupole-order equations of motion can be found in Naoz et al. (2013a).","Citation Text":["Harrington 1968"],"Citation Start End":[[1206,1221]]} {"Identifier":"2020ApJ...900...26P__Pipin_2018_Instance_1","Paragraph":"A detailed description of the dynamo model can be found in our previous paper (Pipin & Kosovichev 2019, hereafter PK19). The model describes the dynamo generation of large-scale magnetic fields (LSMFs) in the bulk of the solar convective zone (CZ). The model is based on the mean-field induction equation (Krause & Rädler 1980):\n1\n\n\n\n\n\nwhere the induction vector of the LSMF, \n\n\n\n\n\n, is represented as the sum of the toroidal and poloidal components:\n\n\n\n\n\nwhere r is the radial distance, θ is the polar angle, and \n\n\n\n\n\n is the unit vector in the azimuthal direction. The mean electromotive force \n\n\n\n\n\n describes the turbulent generation effects, pumping, and diffusion:\n2\n\n\n\n\n\nwhere the symmetric tensor αij stands for the turbulent generation of the LSMF by kinetic and magnetic helicities, the antisymmetric tensor γij describes the turbulent pumping effect, and the anisotropic (in the general case) tensor ηijk is the eddy diffusivity of the LSMF (Pipin 2018). The large-scale (LS) flow field, \n\n\n\n\n\n, produces the LS toroidal magnetic field from the LS poloidal field by means of the differential rotation, \n\n\n\n\n\n. The meridional circulation, \n\n\n\n\n\n, advects the LSMF in the convection zone. The angular momentum conservation and the equation for the azimuthal component of large-scale vorticity, \n\n\n\n\n\n, determine distributions of the differential rotation and meridional circulation:\n3\n\n\n\n\n\n\n\n4\n\n\n\n\n\nwhere \n\n\n\n\n\n is the turbulent stress tensor:\n5\n\n\n\n\n\n(see detailed description in PK19). Also, \n\n\n\n\n\n is the mean density, \n\n\n\n\n\n is the mean entropy, and \n\n\n\n\n\n is the gradient along the axis of rotation. The mean heat transport equation determines the mean entropy variations from the reference state due to the generation and dissipation of LSMF and large-scale flows (Pipin & Kitchatinov 2000):\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the mean temperature, Fr is the radiative heat flux, and Fc is the anisotropic convective flux. An analytical mean-field expression for Fc takes into account the effect of the Coriolis force, and the influence of the LSMF on the turbulent convection (see PK19). The last two terms in Equation (6) take into account the convective energy gain and sink caused by the generation and dissipation of LSMF and large-scale flows. The reference profiles of mean thermodynamic parameters, such as entropy, density, and temperature are determined from the stellar interior model MESA (Paxton et al. 2011, 2013). The radial profile of the typical convective turnover time, τc, is determined from the MESA code, as well. We assume that τc does not depend on the magnetic field and global flows. The convective rms velocity is determined from the mixing-length approximation\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n is the mixing length, αMLT = 1.9 is the mixing-length parameter, and Hp is the pressure height scale. Equation (7) determines the reference profiles for the eddy heat conductivity, \n\n\n\n\n\n, eddy viscosity, νT, and eddy diffusivity, ηT, as follows:\n8\n\n\n\n\n\n\n\n9\n\n\n\n\n\n\n\n10\n\n\n\n\n\nThe model gives the best agreement of the angular velocity profile with helioseismology results for \n\n\n\n\n\n (PK19). Also, the dynamo model reproduces the solar magnetic cycle period, ∼22 years, if \n\n\n\n\n\n.","Citation Text":["Pipin 2018"],"Citation Start End":[[954,964]]} {"Identifier":"2020MNRAS.497.1301D__Mandel,_Farr_&_Gair_2019_Instance_1","Paragraph":"Let the data be denoted $\\mathscr {D}=\\lbrace \\boldsymbol {\\hat{z}},\\boldsymbol {\\hat{\\theta }},\\boldsymbol {\\hat{s}},\\boldsymbol {\\hat{\\imath }}\\rbrace$ (and possibly the experimental covariance matrix), and $\\mathcal {S}$ be the proposition that we have observed some data thus passing the selection criteria. The probability that a given data set is observed depends on the selection criteria. The likelihood of observing $\\mathscr {D}$ given ϑ and that we have observed some data is (Loredo 2004; Mandel, Farr & Gair 2019)\n(54)$$\\begin{eqnarray*}\r\np(\\mathscr {D}\\mid \\mathcal {S},\\vartheta) =\\frac{p(\\mathcal {S}\\mid \\mathscr {D},\\vartheta)\\, p(\\mathscr {D}\\mid \\vartheta)}{p(\\mathcal {S}\\mid \\vartheta)} =\\frac{p(\\mathcal {S}\\mid \\mathscr {D},\\vartheta)\\, p(\\vartheta \\mid \\mathscr {D})}{\\int \\mathrm{d}\\mathscr {D}^{\\prime }\\, p(\\mathcal {S}\\mid \\mathscr {D}^{\\prime },\\vartheta)\\, p(\\vartheta \\mid \\mathscr {D}^{\\prime })},\r\n\\end{eqnarray*}$$where $p(\\mathcal {S}|\\mathscr {D},\\vartheta)$ is the selection function, and we used Bayes’ theorem in the second equality so $p(\\vartheta |\\mathscr {D}) \\propto p(\\mathscr {D}|\\vartheta)p(\\vartheta)$. If we assume that all objects that exceed some threshold are successfully observed then $p(\\mathcal {S}|\\mathscr {D},\\vartheta)=1$. In the ideal scenario of no selection effects (see Section 3) clearly all possible data sets are observable. In the case of a cut-off, equivalent to replacing with a truncated distribution, as in (5), we have $p(\\mathcal {S}|\\mathscr {D},\\vartheta)=1$ if it exceeds some threshold, and $p(\\mathcal {S}|\\mathscr {D},\\vartheta)=0$ otherwise. Thus, $p(\\mathcal {S}|\\vartheta)$ is the fraction of all possible data sets that are observable given parameters ϑ. From (54) we can see that the form of the posterior distribution subject to selection effects, $p(\\vartheta |\\mathscr {D},\\mathcal {S})$, is simply that of $p(\\vartheta |\\mathscr {D})$ given by (44) but with a different normalization.","Citation Text":["Mandel, Farr & Gair 2019"],"Citation Start End":[[501,525]]} {"Identifier":"2018ApJ...858...64R__Canning_et_al._2011_Instance_1","Paragraph":"The gas inside the filaments may be turbulent and the dissipation of this turbulence could, in principle, also contribute to the filament powering. In order to obtain a very rough estimate of the turbulent dissipation rate, we assume that the velocity dispersion σ in the filaments is at best comparable to the sound speed in the Hα-emitting filament gas. Otherwise, there should be evidence for shock heating but that is not observed. In general, shock heating should lead to a correlation between [N ii]\/Hα emission line ratios and the velocity dispersion of the gas, but such correlations have not been detected in the Perseus and Centaurus clusters where this issue was studied (Hatch et al. 2006; Canning et al. 2011; albeit the caveat that these models did not incorporate non-thermal pressure which could affect the nature of the shocks). The absence of shocks implies that\n19\n\n\n\n\n\nwhere fg is fraction of thermal pressure support in the filament and cs,0 is the sound speed in the absence of any non-thermal pressure in the filament for 104 K. For fg = fcr = fB = 1\/3, we get σ ∼ 24 km s−1. The turbulent power \n\n\n\n\n\n. Typical masses of filaments are in the range from Mfil ∼ 104 to 106 M⊙ (Conselice et al. 2001). Using a filament mass of 106 M⊙ and assuming a turbulence injection scale comparable to the filament width lturb = 60 pc (c.f. Canning et al. 2016 who use smaller value), we get Lturb ∼ 2×1038 erg s−1, which is a few percent of the Hα luminosity of the resolved Horseshoe or Northern filaments in Perseus. This is not a strict upper limit on the contribution of turbulent dissipation as the filament may consist of a number of subfilaments. However, inside the filaments the Hα phase, while possibly not completely volume filling, may be more volume filling than the phase corresponding to the dense molecular gas. Furthermore, the power contributed by turbulent dissipation depends on the uncertain mass in the Hα phase in the filament, and that mass is smaller than the total Mfil mass of the filament adopted above. Most importantly however, the measurements of internal turbulence in the filaments are very difficult because of limited spatial resolution. Current measurements of the velocity dispersion inside the filaments are very likely to be significantly overestimated due to filament or subfilament confusion (Canning et al. 2016) and consequently velocity dispersions could be consistent with values lower than those adopted above. We thus conclude that it is at least plausible that turbulent heating is not the dominant powering mechanism.","Citation Text":["Canning et al. 2011"],"Citation Start End":[[702,721]]} {"Identifier":"2022ApJ...933..243F__Margutti_et_al._2017a_Instance_1","Paragraph":"On 2017 August 17, a gravitational wave (GW) event (GW170817; Abbott et al. 2017a, 2017b) was linked with a faint gamma-ray prompt emission of GRB 170817A (Goldstein et al. 2017; Savchenko et al. 2017). Immediately, GRB 170817A was followed by an extensive observational campaign covering radio, optical, and X-ray bands (see, e.g., Troja et al. 2017; Abbott et al. 2017b; Kisaka et al. 2018; D’Avanzo et al. 2018a, and references therein). The observations of the nonthermal spectrum of GRB 170817A gathered during the first ≈ 900 days after the initial merger were analyzed by several authors. It was shown that they were consistent with synchrotron forward-shock emission generated by the deceleration of an off-axis structured jet with an opening angle θ\n\nj\n ≈ 5° that was observed from a viewing angle in the range of 15° ≤ θ\nobs ≤ 25° (Troja et al. 2017; Kasliwal et al. 2017b; Lamb & Kobayashi 2017, 2018; Resmi et al. 2018; Margutti et al. 2017a; Lazzati et al. 2017; Gottlieb et al. 2018b; Fraija et al. 2019b; Gottlieb et al. 2018b; Hotokezaka et al. 2018; Fraija et al. 2019c). In some proposed models, the off-axis structured jet is formed with an off-axis jet with a cocoon (Lazzati et al. 2017; Gottlieb et al. 2018b; Fraija et al. 2019b) and a shock breakout (Gottlieb et al. 2018b; Hotokezaka et al. 2018; Fraija et al. 2019c; Urrutia et al. 2021). Recently, Hajela et al. (2022) analyzed the latest X-ray and radio observations of GRB 170817A collected with the Chandra X-ray Observatory, the Very Large Array (VLA), and the MeerKAT radio interferometer about 3.3 yr after the initial merger. These new observations did not agree with the best-fit synchrotron curves from the off-axis jet model, thus reporting evidence of a new X-ray emission component. Given these contrasting observations, the authors offered the solution to explain this phenomenon in the context of either radiation from accretion processes on the compact-object remnant or a KN afterglow.","Citation Text":["Margutti et al. 2017a"],"Citation Start End":[[932,953]]} {"Identifier":"2019MNRAS.490.3196P__Lagos_et_al._2018a_Instance_1","Paragraph":"No studies have yet provided an extensive and conclusive kinematics analysis of populations of simulated star-forming galaxies that can be broadly contrasted to the results from slit-like and IFS-like current observations. So far, large uniform-volume simulations have been analysed in order to shed light on the dichotomy and formation of fast and slow rotators (e.g. Penoyre et al. 2017; Li et al. 2018; Schulze et al. 2018, with Illustris and Magneticum) and to quantify the connection between galaxy morphology and spin on the one side and AGN feedback, environment and\/or mergers on the other (Dubois et al. 2016; Rodriguez-Gomez et al. 2017; Choi et al. 2018; Lagos et al. 2018a,b, with Illustris, Horizon-AGN and EAGLE). Recently, van de Sande et al. (2019) have compared structural and kinematic properties of simulated galaxies from EAGLE, Hydrangea (Bahé et al. 2017), Horizon-AGN (Dubois et al. 2016), and Magneticum (Dolag et al., in preparation) with observed galaxies in the SAMI, ATLAS3D, CALIFA, and MASSIVE surveys. However, in most cases these works have principally focused on massive early-type galaxies at $z$ ∼ 0, which are expected to be mostly quenched. This choice has been dictated by the limited numerical resolution of such models, which is generally thought to be insufficient to properly capture even the kiloparsec-scale kinematics of intermediate and low-mass galaxies that are observationally accessible, especially in the low-redshift Universe. Other analyses have investigated the relation between stellar shapes and stellar kinematics with EAGLE and across galaxy types (Thob et al. 2019). Furthermore, there is a rich body of works on the problem of the evolution and conservation of galaxies angular momentum, also informed by the results of large uniform-volume simulations and across galaxy types (e.g. more recently Genel et al. 2015; Lagos et al. 2017, with Illustris and EAGLE). However, in most cases so far, the focus has been placed on the final $z$ = 0 outcome, or on the stellar components, or the analyses have been carried out via theoretical characterizations of galaxies properties (e.g. resolution element-based angular momenta) that cannot be easily contrasted to observations. In fact, so far, no quantitative analysis of the spatially averaged or map-based internal kinematics of star-forming galaxies within large uniform-volume simulations exists.","Citation Text":["Lagos et al. 2018a"],"Citation Start End":[[666,684]]} {"Identifier":"2019MNRAS.490.3196Pvan_de_Sande_et_al._(2019)_Instance_1","Paragraph":"No studies have yet provided an extensive and conclusive kinematics analysis of populations of simulated star-forming galaxies that can be broadly contrasted to the results from slit-like and IFS-like current observations. So far, large uniform-volume simulations have been analysed in order to shed light on the dichotomy and formation of fast and slow rotators (e.g. Penoyre et al. 2017; Li et al. 2018; Schulze et al. 2018, with Illustris and Magneticum) and to quantify the connection between galaxy morphology and spin on the one side and AGN feedback, environment and\/or mergers on the other (Dubois et al. 2016; Rodriguez-Gomez et al. 2017; Choi et al. 2018; Lagos et al. 2018a,b, with Illustris, Horizon-AGN and EAGLE). Recently, van de Sande et al. (2019) have compared structural and kinematic properties of simulated galaxies from EAGLE, Hydrangea (Bahé et al. 2017), Horizon-AGN (Dubois et al. 2016), and Magneticum (Dolag et al., in preparation) with observed galaxies in the SAMI, ATLAS3D, CALIFA, and MASSIVE surveys. However, in most cases these works have principally focused on massive early-type galaxies at $z$ ∼ 0, which are expected to be mostly quenched. This choice has been dictated by the limited numerical resolution of such models, which is generally thought to be insufficient to properly capture even the kiloparsec-scale kinematics of intermediate and low-mass galaxies that are observationally accessible, especially in the low-redshift Universe. Other analyses have investigated the relation between stellar shapes and stellar kinematics with EAGLE and across galaxy types (Thob et al. 2019). Furthermore, there is a rich body of works on the problem of the evolution and conservation of galaxies angular momentum, also informed by the results of large uniform-volume simulations and across galaxy types (e.g. more recently Genel et al. 2015; Lagos et al. 2017, with Illustris and EAGLE). However, in most cases so far, the focus has been placed on the final $z$ = 0 outcome, or on the stellar components, or the analyses have been carried out via theoretical characterizations of galaxies properties (e.g. resolution element-based angular momenta) that cannot be easily contrasted to observations. In fact, so far, no quantitative analysis of the spatially averaged or map-based internal kinematics of star-forming galaxies within large uniform-volume simulations exists.","Citation Text":["van de Sande et al. (2019)"],"Citation Start End":[[738,764]]} {"Identifier":"2019MNRAS.490.3196PThob_et_al._2019_Instance_1","Paragraph":"No studies have yet provided an extensive and conclusive kinematics analysis of populations of simulated star-forming galaxies that can be broadly contrasted to the results from slit-like and IFS-like current observations. So far, large uniform-volume simulations have been analysed in order to shed light on the dichotomy and formation of fast and slow rotators (e.g. Penoyre et al. 2017; Li et al. 2018; Schulze et al. 2018, with Illustris and Magneticum) and to quantify the connection between galaxy morphology and spin on the one side and AGN feedback, environment and\/or mergers on the other (Dubois et al. 2016; Rodriguez-Gomez et al. 2017; Choi et al. 2018; Lagos et al. 2018a,b, with Illustris, Horizon-AGN and EAGLE). Recently, van de Sande et al. (2019) have compared structural and kinematic properties of simulated galaxies from EAGLE, Hydrangea (Bahé et al. 2017), Horizon-AGN (Dubois et al. 2016), and Magneticum (Dolag et al., in preparation) with observed galaxies in the SAMI, ATLAS3D, CALIFA, and MASSIVE surveys. However, in most cases these works have principally focused on massive early-type galaxies at $z$ ∼ 0, which are expected to be mostly quenched. This choice has been dictated by the limited numerical resolution of such models, which is generally thought to be insufficient to properly capture even the kiloparsec-scale kinematics of intermediate and low-mass galaxies that are observationally accessible, especially in the low-redshift Universe. Other analyses have investigated the relation between stellar shapes and stellar kinematics with EAGLE and across galaxy types (Thob et al. 2019). Furthermore, there is a rich body of works on the problem of the evolution and conservation of galaxies angular momentum, also informed by the results of large uniform-volume simulations and across galaxy types (e.g. more recently Genel et al. 2015; Lagos et al. 2017, with Illustris and EAGLE). However, in most cases so far, the focus has been placed on the final $z$ = 0 outcome, or on the stellar components, or the analyses have been carried out via theoretical characterizations of galaxies properties (e.g. resolution element-based angular momenta) that cannot be easily contrasted to observations. In fact, so far, no quantitative analysis of the spatially averaged or map-based internal kinematics of star-forming galaxies within large uniform-volume simulations exists.","Citation Text":["Thob et al. 2019"],"Citation Start End":[[1607,1623]]} {"Identifier":"2020ApJ...891L..42T__Kamionkowski_et_al._1998_Instance_1","Paragraph":"The primary focus of this Letter is the spatial distribution of galaxies and their orientations projected onto the sky. While the former is characterized by the fluctuations of number density, denoted by \n\n\n\n\n\n, the latter is quantified by the two-component ellipticity, (γ+ , γ× ), defined with the minor-to-major-axis ratio q on the celestial sphere:\n1\n\n\n\n\n\nwith ϕx being the misalignment angle relative to the reference axis. We will below set q to zero for simplicity, which corresponds to the galaxy being assumed to be a line along its major axis (Okumura et al. 2009). In the weak-lensing measurements, a more convenient characterization of the ellipticity distribution is the rotation-invariant decomposition called E-\/B-modes, \n\n\n\n\n\n (Kamionkowski et al. 1998; Crittenden et al. 2002), and these are defined, in Fourier space, by \n\n\n\n\n\n, where \n\n\n\n\n\n are the Fourier counterpart of the ellipticity fields, and ϕk is the azimuthal angle of the wavevector projected on the celestial sphere, measured from the x-axis. Then, we consider the two-point statistics among \n\n\n\n\n\n and \n\n\n\n\n\n. To quantify the cosmological information encoded in these statistics, we adopt the LA model as mentioned above. In Fourier space, it is given by\n2\n\n\n\n\n\nwith \n\n\n\n\n\n being the redshift-dependent coefficient (Okumura & Taruya 2020). Here we used the Poisson equation to relate the gravitational potential to the mass density field, \n\n\n\n\n\n. Note that the observable ellipticities are density-weighted, i.e., \n\n\n\n\n\n, but at large scales, the term \n\n\n\n\n\n is higher order and can be ignored. Then Equation (2) leads to γB = 0, and the nonvanishing two-point statistics in Fourier space become the auto-power spectra of the galaxy density and E-mode ellipticity, and their cross power spectrum, which we respectively denote by Pgg, PEE, and PgE. In redshift space, where the line-of-sight position of galaxies is determined by the redshift, the observed galaxy density field is affected by the effect of RSD. Furthermore, the ellipticity of galaxies is measured on the celestial sphere normal to the line of sight. Thus, all the power spectra considered here exhibit anisotropies along the line-of-sight direction, and denoting the directional cosine between the wavevector and line-of-sight direction by μ, they are expressed as a function of k and μ. In the linear theory limit, we have (see Okumura & Taruya 2020, for their configuration-space counterparts)\n3\n\n\n\n\n\n\n\n4\n\n\n\n\n\n\n\n5\n\n\n\n\n\nHere, we assume the linear bias relation between the galaxy and matter density fields, and b1 is the coefficient. The quantity f is the linear growth rate defined by \n\n\n\n\n\n with a and D being, respectively, the scale factor of the universe and linear growth factor, and \n\n\n\n\n\n is the linear-order matter power spectrum at the redshift z.","Citation Text":["Kamionkowski et al. 1998"],"Citation Start End":[[744,768]]} {"Identifier":"2015ApJ...811..127S__Leenaarts_et_al._2013a_Instance_1","Paragraph":"Figures 4 and 5 display two enlarged regions from Figure 3, Region 1 being quiet Sun and Region 2 being plage. We have plotted a variety of statistics in these plots that measure the components of the profiles. The emission at h1v generally originates in the upper photosphere. Based on inspection of this and additional higher spatial resolution IRIS data sets, we determine that the structures are a mix of reverse granulation and grains. At h2v, much of the small granular structure disappears and a diffuse halo of bright structures overlay and surround magnetic concentrations. The brightest plage is almost twice as bright as the brightest network, and the maximum h2v emission occurs near the center of the magnetic flux concentration. Single-peaked profiles are relativity common (∼10%) in plage, as depicted by the contiguous red regions in Figure 4. Figure 6(a) shows an example of a single-peaked plage profile. While our algorithm separates between single-peaked and double-peaked profiles to aid in statistical analysis, there is in fact a smooth continuum of weakly separated, weakly reversed profiles that bridge those two profile categories (Figure 6(c) shows an example). In the semi-empirical models of the solar atmosphere, the Mg ii h source function above the temperature minimum has a local maximum at an altitude of 1.2 Mm (see Figure 7 in Leenaarts et al. 2013a), while the line core forms near a height of 2 Mm. To produce a single-peaked profile the atmosphere must be structured such that source function does not vary significantly between \n\n\n\n\n\n at h2 and h3. At high densities, the source function closely adheres to the Planck function, which rises through the chromosphere. These profiles are consistent with the model that hot high-density loops are rooted in plage. Most sunspot profiles are single peaked, and an example is displayed in Figure 6(e). Single-peaked umbral profiles were previously reported in Lites & Skumanich (1982) and Morrill et al. (2001). Sunspot profiles are half as bright at h2 and 20% narrower at h1 than plage. The far wing intensity (beyond h1) is lower in sunspots than plage or internetwork. Single-peaked profiles also occur in internetwork regions, albeit at much lower frequency (∼1%). Figure 6(b) shows a typical internetwork single-peaked profile. Although this profile contains a single maximum, it still requires a substantial contribution from the negative Gaussian amplitude (h in Equation (1)) to achieve a low \n\n\n\n\n\n Figures 6(d) and (f) show profiles that occur at low frequencies in the internetwork (\n\n\n\n\n\n). These profiles represent some of the extreme variations from the mean profile shape that we observe in this large data set. The profile of Figure 6(d) could be produced by extreme upflows in the upper chromosphere that completely mask the photons in the nominal position of the h2v peak and wing. Figure 6(f) illustrates Mg ii h in absorption, which requires that the source function monotonically decrease from the photosphere precluding the mid-chromospheric temperature rise.","Citation Text":["Leenaarts et al. 2013a"],"Citation Start End":[[1363,1385]]} {"Identifier":"2021MNRAS.505.5862W__diamond,_Hill_et_al._2002_Instance_1","Paragraph":"For case 1, we find that most of the stellar values of the MW halo ([Fe\/H] −1) reside between the evolutionary tracks explored here and also in the coloured region. Note that the carbon stars are excluded in Fig. 5, since they might have been contaminated by the binary mass transfer from former asymptotic-giant-branch stars. The smaller SFE for a less-massive galaxy leads to an increase of [Eu\/Fe] at a lower [Fe\/H]. It is notable that our model predicts that almost all highly r-process-enhanced stars ([Eu\/Fe] > 1 at [Fe\/H] ∼ −3) originate from UFD-sized (M* 105) building blocks [but see a caution in Section 4 for the applicability of the mass–metallicity relation of Kirby et al. (2013) to UFD-sized systems], as also suggested in Ishimaru et al. (2015) and Ojima et al. (2018). For instance, our model suggests that J1521−3538 (star, the highest measured Eu\/Fe, Cain et al. 2020) and CS 31082−001 (diamond, Hill et al. 2002) were born in building-block galaxies of M* ∼ 103 and 5 × 103 (in M⊙), respectively. This is a consequence of the fact that a less-massive galaxy contains a smaller amount of gas to be mixed with Eu from an NSM. In fact, the highly eccentric orbit of the former indicates that J1521−3538 originates from a building-block galaxy subsequently accreted by the MW (Cain et al. 2020). In contrast, the r-process-deficient stars may have been born in the most-massive building-block galaxies of M* ∼ 108 M⊙, like HD 4306 (circle, the lowest measured Eu\/Fe, Ishimaru et al. 2004) and HD 122563 (triangle, Honda et al. 2006). Note that our model predicts the presence of even further r-process-deficient stars with [Eu\/Fe] −1 at [Fe\/H] ≲ −3. The absence of such stars with measured Eu is likely due to the current detection limit for Eu (Ishimaru et al. 2004). Overall, the result for case 1 (a mean delay of 0.1 Gyr in the lognormal term for NSMs) appears in qualitative agreement with those in Ishimaru et al. (2015) and Ojima et al. (2018) with a fixed delay of 0.1 Gyr (see Appendix A for additional tests).","Citation Text":["Hill et al. 2002"],"Citation Start End":[[918,934]]} {"Identifier":"2021MNRAS.505.5862WOjima_et_al._(2018)_Instance_1","Paragraph":"For case 1, we find that most of the stellar values of the MW halo ([Fe\/H] −1) reside between the evolutionary tracks explored here and also in the coloured region. Note that the carbon stars are excluded in Fig. 5, since they might have been contaminated by the binary mass transfer from former asymptotic-giant-branch stars. The smaller SFE for a less-massive galaxy leads to an increase of [Eu\/Fe] at a lower [Fe\/H]. It is notable that our model predicts that almost all highly r-process-enhanced stars ([Eu\/Fe] > 1 at [Fe\/H] ∼ −3) originate from UFD-sized (M* 105) building blocks [but see a caution in Section 4 for the applicability of the mass–metallicity relation of Kirby et al. (2013) to UFD-sized systems], as also suggested in Ishimaru et al. (2015) and Ojima et al. (2018). For instance, our model suggests that J1521−3538 (star, the highest measured Eu\/Fe, Cain et al. 2020) and CS 31082−001 (diamond, Hill et al. 2002) were born in building-block galaxies of M* ∼ 103 and 5 × 103 (in M⊙), respectively. This is a consequence of the fact that a less-massive galaxy contains a smaller amount of gas to be mixed with Eu from an NSM. In fact, the highly eccentric orbit of the former indicates that J1521−3538 originates from a building-block galaxy subsequently accreted by the MW (Cain et al. 2020). In contrast, the r-process-deficient stars may have been born in the most-massive building-block galaxies of M* ∼ 108 M⊙, like HD 4306 (circle, the lowest measured Eu\/Fe, Ishimaru et al. 2004) and HD 122563 (triangle, Honda et al. 2006). Note that our model predicts the presence of even further r-process-deficient stars with [Eu\/Fe] −1 at [Fe\/H] ≲ −3. The absence of such stars with measured Eu is likely due to the current detection limit for Eu (Ishimaru et al. 2004). Overall, the result for case 1 (a mean delay of 0.1 Gyr in the lognormal term for NSMs) appears in qualitative agreement with those in Ishimaru et al. (2015) and Ojima et al. (2018) with a fixed delay of 0.1 Gyr (see Appendix A for additional tests).","Citation Text":["Ojima et al. (2018)"],"Citation Start End":[[768,787]]} {"Identifier":"2021MNRAS.505.5862WOjima_et_al._(2018)_Instance_2","Paragraph":"For case 1, we find that most of the stellar values of the MW halo ([Fe\/H] −1) reside between the evolutionary tracks explored here and also in the coloured region. Note that the carbon stars are excluded in Fig. 5, since they might have been contaminated by the binary mass transfer from former asymptotic-giant-branch stars. The smaller SFE for a less-massive galaxy leads to an increase of [Eu\/Fe] at a lower [Fe\/H]. It is notable that our model predicts that almost all highly r-process-enhanced stars ([Eu\/Fe] > 1 at [Fe\/H] ∼ −3) originate from UFD-sized (M* 105) building blocks [but see a caution in Section 4 for the applicability of the mass–metallicity relation of Kirby et al. (2013) to UFD-sized systems], as also suggested in Ishimaru et al. (2015) and Ojima et al. (2018). For instance, our model suggests that J1521−3538 (star, the highest measured Eu\/Fe, Cain et al. 2020) and CS 31082−001 (diamond, Hill et al. 2002) were born in building-block galaxies of M* ∼ 103 and 5 × 103 (in M⊙), respectively. This is a consequence of the fact that a less-massive galaxy contains a smaller amount of gas to be mixed with Eu from an NSM. In fact, the highly eccentric orbit of the former indicates that J1521−3538 originates from a building-block galaxy subsequently accreted by the MW (Cain et al. 2020). In contrast, the r-process-deficient stars may have been born in the most-massive building-block galaxies of M* ∼ 108 M⊙, like HD 4306 (circle, the lowest measured Eu\/Fe, Ishimaru et al. 2004) and HD 122563 (triangle, Honda et al. 2006). Note that our model predicts the presence of even further r-process-deficient stars with [Eu\/Fe] −1 at [Fe\/H] ≲ −3. The absence of such stars with measured Eu is likely due to the current detection limit for Eu (Ishimaru et al. 2004). Overall, the result for case 1 (a mean delay of 0.1 Gyr in the lognormal term for NSMs) appears in qualitative agreement with those in Ishimaru et al. (2015) and Ojima et al. (2018) with a fixed delay of 0.1 Gyr (see Appendix A for additional tests).","Citation Text":["Ojima et al. (2018)"],"Citation Start End":[[1951,1970]]} {"Identifier":"2021MNRAS.505.5862WHonda_et_al._2006_Instance_1","Paragraph":"For case 1, we find that most of the stellar values of the MW halo ([Fe\/H] −1) reside between the evolutionary tracks explored here and also in the coloured region. Note that the carbon stars are excluded in Fig. 5, since they might have been contaminated by the binary mass transfer from former asymptotic-giant-branch stars. The smaller SFE for a less-massive galaxy leads to an increase of [Eu\/Fe] at a lower [Fe\/H]. It is notable that our model predicts that almost all highly r-process-enhanced stars ([Eu\/Fe] > 1 at [Fe\/H] ∼ −3) originate from UFD-sized (M* 105) building blocks [but see a caution in Section 4 for the applicability of the mass–metallicity relation of Kirby et al. (2013) to UFD-sized systems], as also suggested in Ishimaru et al. (2015) and Ojima et al. (2018). For instance, our model suggests that J1521−3538 (star, the highest measured Eu\/Fe, Cain et al. 2020) and CS 31082−001 (diamond, Hill et al. 2002) were born in building-block galaxies of M* ∼ 103 and 5 × 103 (in M⊙), respectively. This is a consequence of the fact that a less-massive galaxy contains a smaller amount of gas to be mixed with Eu from an NSM. In fact, the highly eccentric orbit of the former indicates that J1521−3538 originates from a building-block galaxy subsequently accreted by the MW (Cain et al. 2020). In contrast, the r-process-deficient stars may have been born in the most-massive building-block galaxies of M* ∼ 108 M⊙, like HD 4306 (circle, the lowest measured Eu\/Fe, Ishimaru et al. 2004) and HD 122563 (triangle, Honda et al. 2006). Note that our model predicts the presence of even further r-process-deficient stars with [Eu\/Fe] −1 at [Fe\/H] ≲ −3. The absence of such stars with measured Eu is likely due to the current detection limit for Eu (Ishimaru et al. 2004). Overall, the result for case 1 (a mean delay of 0.1 Gyr in the lognormal term for NSMs) appears in qualitative agreement with those in Ishimaru et al. (2015) and Ojima et al. (2018) with a fixed delay of 0.1 Gyr (see Appendix A for additional tests).","Citation Text":["Honda et al. 2006"],"Citation Start End":[[1533,1550]]} {"Identifier":"2019ApJ...881..157B__Zahid_et_al._2014_Instance_1","Paragraph":"As to the chemical enrichment history of individual galaxies, we have exploited the standard code che-evo incorporated into GRASIL (Silva et al. 1998, 2011; Bressan et al. 2002; Panuzzo et al. 2003; Vega et al. 2005). For spheroidal galaxies, it reproduces the observed local relationship between stellar metallicity and stellar mass and its weak evolution with redshift (see Arrigoni et al. 2010; Spolaor et al. 2010; Gallazzi et al. 2014). For disk galaxies at z ≲ 2, it reproduces the observed relationship between gas metallicity and stellar mass, including its appreciable redshift dependence (see Andrews & Martini 2013; Zahid et al. 2014; de la Rosa et al. 2016; Onodera et al. 2016). In both cases, within an individual galaxy the metallicity behavior is closely approximated by\n4\n\n\n\n\n\ni.e., it increases from Z = 0 almost linearly with the galactic age, and then after a time τ = Δτψ it saturates to the value Zsat. The dependence of Zsat and Δ on SFR\/stellar mass can be described with an expression inspired by analytic chemical evolution models (see Cai et al. 2013; Feldmann 2015); this yields\n5\n\n\n\n\n\nhere s ≈ 3 is the ratio between the dynamical timescale of the infalling gas and the star formation timescale, \n\n\n\n\n\n is the recycling stellar mass fraction, \n\n\n\n\n\n is the metal yield (assuming the Romano et al. 2010 stellar yields), and out is the mass-loading factor of galactic outflows from stellar winds and SN explosions. In the above equation we have provided a fit for out as a function of the final stellar mass M⋆ from the results of the che-evo code; a similar expression concurrently describes the time-averaged outcome from hydrodynamical simulations of stellar feedback (e.g., Hopkins et al. 2012). As a result, typical values \n\n\n\n\n\n are obtained for galaxies with final stellar masses in the range M⋆ ∼ 109–1011 M⊙, respectively (see, e.g., Chruslinska et al. 2019); the related quantity Δ ∼ 0.1–0.3 specifies how quickly the metallicity saturates to such values as a consequence of the interplay between cooling, dilution, and feedback processes. Note that several chemical evolution codes present in the literature, reproducing comparably well observations on the chemical abundances in galaxies of different stellar masses, also share a similar age-dependent metallicity behavior.","Citation Text":["Zahid et al. 2014"],"Citation Start End":[[627,644]]} {"Identifier":"2019ApJ...881..157BCai_et_al._2013_Instance_1","Paragraph":"As to the chemical enrichment history of individual galaxies, we have exploited the standard code che-evo incorporated into GRASIL (Silva et al. 1998, 2011; Bressan et al. 2002; Panuzzo et al. 2003; Vega et al. 2005). For spheroidal galaxies, it reproduces the observed local relationship between stellar metallicity and stellar mass and its weak evolution with redshift (see Arrigoni et al. 2010; Spolaor et al. 2010; Gallazzi et al. 2014). For disk galaxies at z ≲ 2, it reproduces the observed relationship between gas metallicity and stellar mass, including its appreciable redshift dependence (see Andrews & Martini 2013; Zahid et al. 2014; de la Rosa et al. 2016; Onodera et al. 2016). In both cases, within an individual galaxy the metallicity behavior is closely approximated by\n4\n\n\n\n\n\ni.e., it increases from Z = 0 almost linearly with the galactic age, and then after a time τ = Δτψ it saturates to the value Zsat. The dependence of Zsat and Δ on SFR\/stellar mass can be described with an expression inspired by analytic chemical evolution models (see Cai et al. 2013; Feldmann 2015); this yields\n5\n\n\n\n\n\nhere s ≈ 3 is the ratio between the dynamical timescale of the infalling gas and the star formation timescale, \n\n\n\n\n\n is the recycling stellar mass fraction, \n\n\n\n\n\n is the metal yield (assuming the Romano et al. 2010 stellar yields), and out is the mass-loading factor of galactic outflows from stellar winds and SN explosions. In the above equation we have provided a fit for out as a function of the final stellar mass M⋆ from the results of the che-evo code; a similar expression concurrently describes the time-averaged outcome from hydrodynamical simulations of stellar feedback (e.g., Hopkins et al. 2012). As a result, typical values \n\n\n\n\n\n are obtained for galaxies with final stellar masses in the range M⋆ ∼ 109–1011 M⊙, respectively (see, e.g., Chruslinska et al. 2019); the related quantity Δ ∼ 0.1–0.3 specifies how quickly the metallicity saturates to such values as a consequence of the interplay between cooling, dilution, and feedback processes. Note that several chemical evolution codes present in the literature, reproducing comparably well observations on the chemical abundances in galaxies of different stellar masses, also share a similar age-dependent metallicity behavior.","Citation Text":["Cai et al. 2013"],"Citation Start End":[[1062,1077]]} {"Identifier":"2019ApJ...881..157BVega_et_al._2005_Instance_1","Paragraph":"As to the chemical enrichment history of individual galaxies, we have exploited the standard code che-evo incorporated into GRASIL (Silva et al. 1998, 2011; Bressan et al. 2002; Panuzzo et al. 2003; Vega et al. 2005). For spheroidal galaxies, it reproduces the observed local relationship between stellar metallicity and stellar mass and its weak evolution with redshift (see Arrigoni et al. 2010; Spolaor et al. 2010; Gallazzi et al. 2014). For disk galaxies at z ≲ 2, it reproduces the observed relationship between gas metallicity and stellar mass, including its appreciable redshift dependence (see Andrews & Martini 2013; Zahid et al. 2014; de la Rosa et al. 2016; Onodera et al. 2016). In both cases, within an individual galaxy the metallicity behavior is closely approximated by\n4\n\n\n\n\n\ni.e., it increases from Z = 0 almost linearly with the galactic age, and then after a time τ = Δτψ it saturates to the value Zsat. The dependence of Zsat and Δ on SFR\/stellar mass can be described with an expression inspired by analytic chemical evolution models (see Cai et al. 2013; Feldmann 2015); this yields\n5\n\n\n\n\n\nhere s ≈ 3 is the ratio between the dynamical timescale of the infalling gas and the star formation timescale, \n\n\n\n\n\n is the recycling stellar mass fraction, \n\n\n\n\n\n is the metal yield (assuming the Romano et al. 2010 stellar yields), and out is the mass-loading factor of galactic outflows from stellar winds and SN explosions. In the above equation we have provided a fit for out as a function of the final stellar mass M⋆ from the results of the che-evo code; a similar expression concurrently describes the time-averaged outcome from hydrodynamical simulations of stellar feedback (e.g., Hopkins et al. 2012). As a result, typical values \n\n\n\n\n\n are obtained for galaxies with final stellar masses in the range M⋆ ∼ 109–1011 M⊙, respectively (see, e.g., Chruslinska et al. 2019); the related quantity Δ ∼ 0.1–0.3 specifies how quickly the metallicity saturates to such values as a consequence of the interplay between cooling, dilution, and feedback processes. Note that several chemical evolution codes present in the literature, reproducing comparably well observations on the chemical abundances in galaxies of different stellar masses, also share a similar age-dependent metallicity behavior.","Citation Text":["Vega et al. 2005"],"Citation Start End":[[199,215]]} {"Identifier":"2019ApJ...881..157BHopkins_et_al._2012_Instance_1","Paragraph":"As to the chemical enrichment history of individual galaxies, we have exploited the standard code che-evo incorporated into GRASIL (Silva et al. 1998, 2011; Bressan et al. 2002; Panuzzo et al. 2003; Vega et al. 2005). For spheroidal galaxies, it reproduces the observed local relationship between stellar metallicity and stellar mass and its weak evolution with redshift (see Arrigoni et al. 2010; Spolaor et al. 2010; Gallazzi et al. 2014). For disk galaxies at z ≲ 2, it reproduces the observed relationship between gas metallicity and stellar mass, including its appreciable redshift dependence (see Andrews & Martini 2013; Zahid et al. 2014; de la Rosa et al. 2016; Onodera et al. 2016). In both cases, within an individual galaxy the metallicity behavior is closely approximated by\n4\n\n\n\n\n\ni.e., it increases from Z = 0 almost linearly with the galactic age, and then after a time τ = Δτψ it saturates to the value Zsat. The dependence of Zsat and Δ on SFR\/stellar mass can be described with an expression inspired by analytic chemical evolution models (see Cai et al. 2013; Feldmann 2015); this yields\n5\n\n\n\n\n\nhere s ≈ 3 is the ratio between the dynamical timescale of the infalling gas and the star formation timescale, \n\n\n\n\n\n is the recycling stellar mass fraction, \n\n\n\n\n\n is the metal yield (assuming the Romano et al. 2010 stellar yields), and out is the mass-loading factor of galactic outflows from stellar winds and SN explosions. In the above equation we have provided a fit for out as a function of the final stellar mass M⋆ from the results of the che-evo code; a similar expression concurrently describes the time-averaged outcome from hydrodynamical simulations of stellar feedback (e.g., Hopkins et al. 2012). As a result, typical values \n\n\n\n\n\n are obtained for galaxies with final stellar masses in the range M⋆ ∼ 109–1011 M⊙, respectively (see, e.g., Chruslinska et al. 2019); the related quantity Δ ∼ 0.1–0.3 specifies how quickly the metallicity saturates to such values as a consequence of the interplay between cooling, dilution, and feedback processes. Note that several chemical evolution codes present in the literature, reproducing comparably well observations on the chemical abundances in galaxies of different stellar masses, also share a similar age-dependent metallicity behavior.","Citation Text":["Hopkins et al. 2012"],"Citation Start End":[[1705,1724]]} {"Identifier":"2020MNRAS.498.5299M__Munshi_et_al._1999b_Instance_1","Paragraph":"The unsmoothed normalized higher order cumulants or $S_N = \\langle \\delta ^N \\rangle _c\/\\langle \\delta ^2 \\rangle ^{N-1}_c$ can be expressed in terms of the tree-level vertices denoted as νN using the following expressions (Bernardeau et al. 2002a):\n(20)$$\\begin{eqnarray*}\r\n&& S_3 = 3\\nu _2; \\quad S_4 = 4\\nu _3+ 12\\nu _2^2; \\quad S_5 = 5\\nu _4+ 60\\nu _3\\nu _2 + 60\\nu _2^3. \\quad\r\n\\end{eqnarray*}$$The vertices νN are the angular averages of the mode-coupling kernels FN defined in equation (1c) i.e. νN = N!〈 FN〉 introduced in Section 2.2 in the Fourier domain.\n(21)$$\\begin{eqnarray*}\r\n&& \\nu _N = N!\\langle F_N \\rangle = N! \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_1} \\over 4\\pi } \\cdots \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_N} \\over 4\\pi } F_N({\\bf k}_1.\\cdots , {\\bf k}_N);\\quad \\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_k = \\sin \\theta _k \\mathrm{ d}\\theta _k \\mathrm{ d}\\varphi _k.\r\n\\end{eqnarray*}$$The following generating function approach was introduced in Bernardeau (1992, 1994b). The generating functions ${\\cal G}_{\\delta }(\\tau)$ are solved using the equations of gravitational dynamics encapsulated in Euler–Continuity–Poisson equations. Here, τ plays the role of a dummy variable. In the perturbative regime, the νN parameter can be computed for an arbitrary N(22)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }(\\tau) = \\sum _{n}{\\nu _N \\over N!}\\tau ^N = -\\tau + {12 \\over 14} \\tau ^2 - {29 \\over 42} \\tau ^3 + {79 \\over 147} \\tau ^4 - {2085 \\over 5096} \\tau ^5 + \\cdots\r\n\\end{eqnarray*}$$Next, using equation (20), the one-point cumulants in 2D (Munshi et al. 1999b), denoted as ΣN as opposed to SN parameters which represent the cumulants in 3D, can be used to compute the cumulants to arbitrary order in 2D (Munshi et al. 1999b)\n(23)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36\\over 7}; \\quad \\Sigma _4={2540 \\over 49}; \\quad \\Sigma _5={793}; \\quad \\Sigma _6=16370;\r\n\\end{eqnarray*}$$The generalization of the one-point cumulants i.e the SN parameters to the two-point cumulant correlators $C_{pq} = \\langle \\delta ^p_1\\delta _2^q\\rangle _c\/\\langle \\delta ^2\\rangle _c^{p+q-1}\\langle \\delta _1\\delta _2\\rangle _c$ or Cpq parameters was introduced in Bernardeau (1996a). The lower order normalized cumulant correlators can also be expressed in terms of the tree-level vertices νN just as the one-point cumulants introduced in equation (20)\n(24)$$\\begin{eqnarray*}\r\n&& C_{21} = 2\\nu _2; \\quad C_{31} = 3\\nu _3+ 6\\nu _2^2; \\quad C_{41} = 4\\nu _4 + 36 \\nu _3\\nu _2 + 24 \\nu _2^3.\r\n\\end{eqnarray*}$$The corresponding quantities for convergence maps can be defined in an analogous manner and are denoted with a superscript κ i.e. $C^{\\kappa }_{pq}$. To compare with observed or simulated data smoothing of the field is necessary. The smoothed generating function ${\\cal G}^s_{\\delta }$ can be computed from the unsmoothed generating function ${\\cal G}_{\\delta }$. The generating functions ${\\cal G}^s_{\\delta }$ and ${\\cal G}_{\\delta }$ are related by the following implicit relation (Bernardeau 1995):\n(25)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }^s(\\tau)= {\\cal G}_{\\delta }(\\tau [1+ {\\cal G}_{\\delta }^s]^{-(2+n)\/4}).\r\n\\end{eqnarray*}$$A top hat smoothing window is assumed and the power spectrum is approximated locally as a power law P(k) ∝ kn (Bernardeau 1995; Munshi et al. 1999b). For other window functions, e.g. Gaussian window generic results are not possible for arbitrary N. However, an order-by-order approach can be adopted to obtain the lower order cumulants (Matsubara 2003). Notice that the smoothed power law depends on the spectral index while unsmoothed vertices depend solely on the gravitational collapse in 3D spherical or cylindrical in 2D. The smoothed vertices can be recovered by Taylor-expanding the smoothed generating function ${\\cal G}^s$. Using these vertices, it is possible to now compute the 2D skewness Σ3 and kurtosis Σ4 can be computed (Munshi et al. 1999b)\n(26a)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36 \\over 7} -{3\\over 2} (n+2);\r\n\\end{eqnarray*}$$(26b)$$\\begin{eqnarray*}\r\n&& \\Sigma _4 = {2540 \\over 49} - 33(n+2) + {21 \\over 4}(n+2)^2.\r\n\\end{eqnarray*}$$","Citation Text":["Munshi et al. 1999b"],"Citation Start End":[[1598,1617]]} {"Identifier":"2020MNRAS.498.5299M__Munshi_et_al._1999b_Instance_2","Paragraph":"The unsmoothed normalized higher order cumulants or $S_N = \\langle \\delta ^N \\rangle _c\/\\langle \\delta ^2 \\rangle ^{N-1}_c$ can be expressed in terms of the tree-level vertices denoted as νN using the following expressions (Bernardeau et al. 2002a):\n(20)$$\\begin{eqnarray*}\r\n&& S_3 = 3\\nu _2; \\quad S_4 = 4\\nu _3+ 12\\nu _2^2; \\quad S_5 = 5\\nu _4+ 60\\nu _3\\nu _2 + 60\\nu _2^3. \\quad\r\n\\end{eqnarray*}$$The vertices νN are the angular averages of the mode-coupling kernels FN defined in equation (1c) i.e. νN = N!〈 FN〉 introduced in Section 2.2 in the Fourier domain.\n(21)$$\\begin{eqnarray*}\r\n&& \\nu _N = N!\\langle F_N \\rangle = N! \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_1} \\over 4\\pi } \\cdots \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_N} \\over 4\\pi } F_N({\\bf k}_1.\\cdots , {\\bf k}_N);\\quad \\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_k = \\sin \\theta _k \\mathrm{ d}\\theta _k \\mathrm{ d}\\varphi _k.\r\n\\end{eqnarray*}$$The following generating function approach was introduced in Bernardeau (1992, 1994b). The generating functions ${\\cal G}_{\\delta }(\\tau)$ are solved using the equations of gravitational dynamics encapsulated in Euler–Continuity–Poisson equations. Here, τ plays the role of a dummy variable. In the perturbative regime, the νN parameter can be computed for an arbitrary N(22)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }(\\tau) = \\sum _{n}{\\nu _N \\over N!}\\tau ^N = -\\tau + {12 \\over 14} \\tau ^2 - {29 \\over 42} \\tau ^3 + {79 \\over 147} \\tau ^4 - {2085 \\over 5096} \\tau ^5 + \\cdots\r\n\\end{eqnarray*}$$Next, using equation (20), the one-point cumulants in 2D (Munshi et al. 1999b), denoted as ΣN as opposed to SN parameters which represent the cumulants in 3D, can be used to compute the cumulants to arbitrary order in 2D (Munshi et al. 1999b)\n(23)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36\\over 7}; \\quad \\Sigma _4={2540 \\over 49}; \\quad \\Sigma _5={793}; \\quad \\Sigma _6=16370;\r\n\\end{eqnarray*}$$The generalization of the one-point cumulants i.e the SN parameters to the two-point cumulant correlators $C_{pq} = \\langle \\delta ^p_1\\delta _2^q\\rangle _c\/\\langle \\delta ^2\\rangle _c^{p+q-1}\\langle \\delta _1\\delta _2\\rangle _c$ or Cpq parameters was introduced in Bernardeau (1996a). The lower order normalized cumulant correlators can also be expressed in terms of the tree-level vertices νN just as the one-point cumulants introduced in equation (20)\n(24)$$\\begin{eqnarray*}\r\n&& C_{21} = 2\\nu _2; \\quad C_{31} = 3\\nu _3+ 6\\nu _2^2; \\quad C_{41} = 4\\nu _4 + 36 \\nu _3\\nu _2 + 24 \\nu _2^3.\r\n\\end{eqnarray*}$$The corresponding quantities for convergence maps can be defined in an analogous manner and are denoted with a superscript κ i.e. $C^{\\kappa }_{pq}$. To compare with observed or simulated data smoothing of the field is necessary. The smoothed generating function ${\\cal G}^s_{\\delta }$ can be computed from the unsmoothed generating function ${\\cal G}_{\\delta }$. The generating functions ${\\cal G}^s_{\\delta }$ and ${\\cal G}_{\\delta }$ are related by the following implicit relation (Bernardeau 1995):\n(25)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }^s(\\tau)= {\\cal G}_{\\delta }(\\tau [1+ {\\cal G}_{\\delta }^s]^{-(2+n)\/4}).\r\n\\end{eqnarray*}$$A top hat smoothing window is assumed and the power spectrum is approximated locally as a power law P(k) ∝ kn (Bernardeau 1995; Munshi et al. 1999b). For other window functions, e.g. Gaussian window generic results are not possible for arbitrary N. However, an order-by-order approach can be adopted to obtain the lower order cumulants (Matsubara 2003). Notice that the smoothed power law depends on the spectral index while unsmoothed vertices depend solely on the gravitational collapse in 3D spherical or cylindrical in 2D. The smoothed vertices can be recovered by Taylor-expanding the smoothed generating function ${\\cal G}^s$. Using these vertices, it is possible to now compute the 2D skewness Σ3 and kurtosis Σ4 can be computed (Munshi et al. 1999b)\n(26a)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36 \\over 7} -{3\\over 2} (n+2);\r\n\\end{eqnarray*}$$(26b)$$\\begin{eqnarray*}\r\n&& \\Sigma _4 = {2540 \\over 49} - 33(n+2) + {21 \\over 4}(n+2)^2.\r\n\\end{eqnarray*}$$","Citation Text":["Munshi et al. 1999b"],"Citation Start End":[[1762,1781]]} {"Identifier":"2020MNRAS.498.5299M__Munshi_et_al._1999b_Instance_3","Paragraph":"The unsmoothed normalized higher order cumulants or $S_N = \\langle \\delta ^N \\rangle _c\/\\langle \\delta ^2 \\rangle ^{N-1}_c$ can be expressed in terms of the tree-level vertices denoted as νN using the following expressions (Bernardeau et al. 2002a):\n(20)$$\\begin{eqnarray*}\r\n&& S_3 = 3\\nu _2; \\quad S_4 = 4\\nu _3+ 12\\nu _2^2; \\quad S_5 = 5\\nu _4+ 60\\nu _3\\nu _2 + 60\\nu _2^3. \\quad\r\n\\end{eqnarray*}$$The vertices νN are the angular averages of the mode-coupling kernels FN defined in equation (1c) i.e. νN = N!〈 FN〉 introduced in Section 2.2 in the Fourier domain.\n(21)$$\\begin{eqnarray*}\r\n&& \\nu _N = N!\\langle F_N \\rangle = N! \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_1} \\over 4\\pi } \\cdots \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_N} \\over 4\\pi } F_N({\\bf k}_1.\\cdots , {\\bf k}_N);\\quad \\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_k = \\sin \\theta _k \\mathrm{ d}\\theta _k \\mathrm{ d}\\varphi _k.\r\n\\end{eqnarray*}$$The following generating function approach was introduced in Bernardeau (1992, 1994b). The generating functions ${\\cal G}_{\\delta }(\\tau)$ are solved using the equations of gravitational dynamics encapsulated in Euler–Continuity–Poisson equations. Here, τ plays the role of a dummy variable. In the perturbative regime, the νN parameter can be computed for an arbitrary N(22)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }(\\tau) = \\sum _{n}{\\nu _N \\over N!}\\tau ^N = -\\tau + {12 \\over 14} \\tau ^2 - {29 \\over 42} \\tau ^3 + {79 \\over 147} \\tau ^4 - {2085 \\over 5096} \\tau ^5 + \\cdots\r\n\\end{eqnarray*}$$Next, using equation (20), the one-point cumulants in 2D (Munshi et al. 1999b), denoted as ΣN as opposed to SN parameters which represent the cumulants in 3D, can be used to compute the cumulants to arbitrary order in 2D (Munshi et al. 1999b)\n(23)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36\\over 7}; \\quad \\Sigma _4={2540 \\over 49}; \\quad \\Sigma _5={793}; \\quad \\Sigma _6=16370;\r\n\\end{eqnarray*}$$The generalization of the one-point cumulants i.e the SN parameters to the two-point cumulant correlators $C_{pq} = \\langle \\delta ^p_1\\delta _2^q\\rangle _c\/\\langle \\delta ^2\\rangle _c^{p+q-1}\\langle \\delta _1\\delta _2\\rangle _c$ or Cpq parameters was introduced in Bernardeau (1996a). The lower order normalized cumulant correlators can also be expressed in terms of the tree-level vertices νN just as the one-point cumulants introduced in equation (20)\n(24)$$\\begin{eqnarray*}\r\n&& C_{21} = 2\\nu _2; \\quad C_{31} = 3\\nu _3+ 6\\nu _2^2; \\quad C_{41} = 4\\nu _4 + 36 \\nu _3\\nu _2 + 24 \\nu _2^3.\r\n\\end{eqnarray*}$$The corresponding quantities for convergence maps can be defined in an analogous manner and are denoted with a superscript κ i.e. $C^{\\kappa }_{pq}$. To compare with observed or simulated data smoothing of the field is necessary. The smoothed generating function ${\\cal G}^s_{\\delta }$ can be computed from the unsmoothed generating function ${\\cal G}_{\\delta }$. The generating functions ${\\cal G}^s_{\\delta }$ and ${\\cal G}_{\\delta }$ are related by the following implicit relation (Bernardeau 1995):\n(25)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }^s(\\tau)= {\\cal G}_{\\delta }(\\tau [1+ {\\cal G}_{\\delta }^s]^{-(2+n)\/4}).\r\n\\end{eqnarray*}$$A top hat smoothing window is assumed and the power spectrum is approximated locally as a power law P(k) ∝ kn (Bernardeau 1995; Munshi et al. 1999b). For other window functions, e.g. Gaussian window generic results are not possible for arbitrary N. However, an order-by-order approach can be adopted to obtain the lower order cumulants (Matsubara 2003). Notice that the smoothed power law depends on the spectral index while unsmoothed vertices depend solely on the gravitational collapse in 3D spherical or cylindrical in 2D. The smoothed vertices can be recovered by Taylor-expanding the smoothed generating function ${\\cal G}^s$. Using these vertices, it is possible to now compute the 2D skewness Σ3 and kurtosis Σ4 can be computed (Munshi et al. 1999b)\n(26a)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36 \\over 7} -{3\\over 2} (n+2);\r\n\\end{eqnarray*}$$(26b)$$\\begin{eqnarray*}\r\n&& \\Sigma _4 = {2540 \\over 49} - 33(n+2) + {21 \\over 4}(n+2)^2.\r\n\\end{eqnarray*}$$","Citation Text":["Munshi et al. 1999b"],"Citation Start End":[[3335,3354]]} {"Identifier":"2020MNRAS.498.5299M__Munshi_et_al._1999b_Instance_4","Paragraph":"The unsmoothed normalized higher order cumulants or $S_N = \\langle \\delta ^N \\rangle _c\/\\langle \\delta ^2 \\rangle ^{N-1}_c$ can be expressed in terms of the tree-level vertices denoted as νN using the following expressions (Bernardeau et al. 2002a):\n(20)$$\\begin{eqnarray*}\r\n&& S_3 = 3\\nu _2; \\quad S_4 = 4\\nu _3+ 12\\nu _2^2; \\quad S_5 = 5\\nu _4+ 60\\nu _3\\nu _2 + 60\\nu _2^3. \\quad\r\n\\end{eqnarray*}$$The vertices νN are the angular averages of the mode-coupling kernels FN defined in equation (1c) i.e. νN = N!〈 FN〉 introduced in Section 2.2 in the Fourier domain.\n(21)$$\\begin{eqnarray*}\r\n&& \\nu _N = N!\\langle F_N \\rangle = N! \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_1} \\over 4\\pi } \\cdots \\int {\\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_{k_N} \\over 4\\pi } F_N({\\bf k}_1.\\cdots , {\\bf k}_N);\\quad \\mathrm{ d}{{\\bf \\widehat{\\Omega }}}_k = \\sin \\theta _k \\mathrm{ d}\\theta _k \\mathrm{ d}\\varphi _k.\r\n\\end{eqnarray*}$$The following generating function approach was introduced in Bernardeau (1992, 1994b). The generating functions ${\\cal G}_{\\delta }(\\tau)$ are solved using the equations of gravitational dynamics encapsulated in Euler–Continuity–Poisson equations. Here, τ plays the role of a dummy variable. In the perturbative regime, the νN parameter can be computed for an arbitrary N(22)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }(\\tau) = \\sum _{n}{\\nu _N \\over N!}\\tau ^N = -\\tau + {12 \\over 14} \\tau ^2 - {29 \\over 42} \\tau ^3 + {79 \\over 147} \\tau ^4 - {2085 \\over 5096} \\tau ^5 + \\cdots\r\n\\end{eqnarray*}$$Next, using equation (20), the one-point cumulants in 2D (Munshi et al. 1999b), denoted as ΣN as opposed to SN parameters which represent the cumulants in 3D, can be used to compute the cumulants to arbitrary order in 2D (Munshi et al. 1999b)\n(23)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36\\over 7}; \\quad \\Sigma _4={2540 \\over 49}; \\quad \\Sigma _5={793}; \\quad \\Sigma _6=16370;\r\n\\end{eqnarray*}$$The generalization of the one-point cumulants i.e the SN parameters to the two-point cumulant correlators $C_{pq} = \\langle \\delta ^p_1\\delta _2^q\\rangle _c\/\\langle \\delta ^2\\rangle _c^{p+q-1}\\langle \\delta _1\\delta _2\\rangle _c$ or Cpq parameters was introduced in Bernardeau (1996a). The lower order normalized cumulant correlators can also be expressed in terms of the tree-level vertices νN just as the one-point cumulants introduced in equation (20)\n(24)$$\\begin{eqnarray*}\r\n&& C_{21} = 2\\nu _2; \\quad C_{31} = 3\\nu _3+ 6\\nu _2^2; \\quad C_{41} = 4\\nu _4 + 36 \\nu _3\\nu _2 + 24 \\nu _2^3.\r\n\\end{eqnarray*}$$The corresponding quantities for convergence maps can be defined in an analogous manner and are denoted with a superscript κ i.e. $C^{\\kappa }_{pq}$. To compare with observed or simulated data smoothing of the field is necessary. The smoothed generating function ${\\cal G}^s_{\\delta }$ can be computed from the unsmoothed generating function ${\\cal G}_{\\delta }$. The generating functions ${\\cal G}^s_{\\delta }$ and ${\\cal G}_{\\delta }$ are related by the following implicit relation (Bernardeau 1995):\n(25)$$\\begin{eqnarray*}\r\n&& {\\cal G}_{\\delta }^s(\\tau)= {\\cal G}_{\\delta }(\\tau [1+ {\\cal G}_{\\delta }^s]^{-(2+n)\/4}).\r\n\\end{eqnarray*}$$A top hat smoothing window is assumed and the power spectrum is approximated locally as a power law P(k) ∝ kn (Bernardeau 1995; Munshi et al. 1999b). For other window functions, e.g. Gaussian window generic results are not possible for arbitrary N. However, an order-by-order approach can be adopted to obtain the lower order cumulants (Matsubara 2003). Notice that the smoothed power law depends on the spectral index while unsmoothed vertices depend solely on the gravitational collapse in 3D spherical or cylindrical in 2D. The smoothed vertices can be recovered by Taylor-expanding the smoothed generating function ${\\cal G}^s$. Using these vertices, it is possible to now compute the 2D skewness Σ3 and kurtosis Σ4 can be computed (Munshi et al. 1999b)\n(26a)$$\\begin{eqnarray*}\r\n&& \\Sigma _3 = {36 \\over 7} -{3\\over 2} (n+2);\r\n\\end{eqnarray*}$$(26b)$$\\begin{eqnarray*}\r\n&& \\Sigma _4 = {2540 \\over 49} - 33(n+2) + {21 \\over 4}(n+2)^2.\r\n\\end{eqnarray*}$$","Citation Text":["Munshi et al. 1999b"],"Citation Start End":[[3944,3963]]} {"Identifier":"2015MNRAS.454.2003P__Baruteau_&_Masset_2008_Instance_1","Paragraph":"Interestingly, the presence of such an underdense librating region at the leading side of the planet has also been observed in simulations of giant planets which undergo inward runaway migration (Artymowicz 2004; D'angelo & Lubow 2008). Here, it is worth noting that the low-density region does not result from the gap opening process but is rather due to radiative effects. Never the less, using the terminology employed in the framework of Type III migration, Fig. 3 shows that radiative effects can give rise to a coorbital mass deficit given by (Masset & Papaloizou 2003)\n\n(8)\n\n\\begin{equation}\n\\delta \\mathrm{m}=4\\pi a x_\\mathrm{s}\\left(\\Sigma _\\mathrm{s}-\\Sigma _h\\right),\n\\end{equation}\n\nwhere Σs is the surface density at the upstream separatrix and Σh the mean surface density in the librating region. In order to provide an estimation for the coorbital mass deficit in the librating region, we make in the following the assumption that the only contribution to the density perturbation in the librating region results from entropy advection. In reality, however, the density perturbation features an additional contribution linked to the production of vortensity at the outgoing separatrix (Paardekooper et al. 2011). Ignoring this contribution gives the following expression for the surface density Σ− in the librating region (Baruteau & Masset 2008; Paardekooper et al. 2011):\n\n(9)\n\n\\begin{equation}\n\\Sigma _-=\\Sigma _\\mathrm{s}\\left(1-2\\frac{\\mid \\xi \\mid x}{\\gamma a}\\right) \\quad \\mathrm{for} \\quad 0 \\dot{a_f}$, however, the expression for the unsaturated corotation torque given by equation (12) is no longer valid and should be modified (Papaloizou et al. 2007). In that case, we expect the corotation torque to be prevented from saturation since the horseshoe region does not longer extend to the full 2π in azimuth, so that phase-mixing cannot occur. In isothermal discs with a large-scale vortensity gradient, Ogilvie & Lubow (2006) found that drift rates with $\\dot{a} > \\dot{a_f}$ can even lead to torques that are much larger than the unsaturated value in absence of migration. They showed that this arises due to corotational torques caused by a vortensity asymmetry in the coorbital region between gas on the leading and trailing sides of the planet. In the limit of low viscosity, the trapped material tends to conserve its initial vortensity as the planet migrates, leading to a possibly significant vortensity contrast between the librating region and the local disc. In that case, the impact on migration depends in fact on the sign of the vortensity deficit (Paardekooper 2014) which is defined as\n\n(14)\n\n\\begin{equation}\n\\delta (\\omega \/\\Sigma )=1-\\frac{\\omega _a\/\\Sigma _a}{\\omega _{0}\/\\Sigma _{0}},\n\\end{equation}\n\nwhere ωa\/Σa is the local disc vortensity at the position of the planet and ω0\/Σ0 the vortensity at the initial location of the planet. In the case where the planet migrates in the direction set by the vortensity-related horseshoe drag, the vortensity deficit is positive and this yields a positive feedback on migration, whereas if the planet migrates in the opposite direction to that set by the corotation torque, the vortensity deficit is negative and this gives rise to a negative feedback on migration (Paardekooper 2014).","Citation Text":["Baruteau & Masset 2008"],"Citation Start End":[[1338,1360]]} {"Identifier":"2015MNRAS.454.2003P__Baruteau_&_Masset_2008_Instance_2","Paragraph":"Interestingly, the presence of such an underdense librating region at the leading side of the planet has also been observed in simulations of giant planets which undergo inward runaway migration (Artymowicz 2004; D'angelo & Lubow 2008). Here, it is worth noting that the low-density region does not result from the gap opening process but is rather due to radiative effects. Never the less, using the terminology employed in the framework of Type III migration, Fig. 3 shows that radiative effects can give rise to a coorbital mass deficit given by (Masset & Papaloizou 2003)\n\n(8)\n\n\\begin{equation}\n\\delta \\mathrm{m}=4\\pi a x_\\mathrm{s}\\left(\\Sigma _\\mathrm{s}-\\Sigma _h\\right),\n\\end{equation}\n\nwhere Σs is the surface density at the upstream separatrix and Σh the mean surface density in the librating region. In order to provide an estimation for the coorbital mass deficit in the librating region, we make in the following the assumption that the only contribution to the density perturbation in the librating region results from entropy advection. In reality, however, the density perturbation features an additional contribution linked to the production of vortensity at the outgoing separatrix (Paardekooper et al. 2011). Ignoring this contribution gives the following expression for the surface density Σ− in the librating region (Baruteau & Masset 2008; Paardekooper et al. 2011):\n\n(9)\n\n\\begin{equation}\n\\Sigma _-=\\Sigma _\\mathrm{s}\\left(1-2\\frac{\\mid \\xi \\mid x}{\\gamma a}\\right) \\quad \\mathrm{for} \\quad 0 \\dot{a_f}$, however, the expression for the unsaturated corotation torque given by equation (12) is no longer valid and should be modified (Papaloizou et al. 2007). In that case, we expect the corotation torque to be prevented from saturation since the horseshoe region does not longer extend to the full 2π in azimuth, so that phase-mixing cannot occur. In isothermal discs with a large-scale vortensity gradient, Ogilvie & Lubow (2006) found that drift rates with $\\dot{a} > \\dot{a_f}$ can even lead to torques that are much larger than the unsaturated value in absence of migration. They showed that this arises due to corotational torques caused by a vortensity asymmetry in the coorbital region between gas on the leading and trailing sides of the planet. In the limit of low viscosity, the trapped material tends to conserve its initial vortensity as the planet migrates, leading to a possibly significant vortensity contrast between the librating region and the local disc. In that case, the impact on migration depends in fact on the sign of the vortensity deficit (Paardekooper 2014) which is defined as\n\n(14)\n\n\\begin{equation}\n\\delta (\\omega \/\\Sigma )=1-\\frac{\\omega _a\/\\Sigma _a}{\\omega _{0}\/\\Sigma _{0}},\n\\end{equation}\n\nwhere ωa\/Σa is the local disc vortensity at the position of the planet and ω0\/Σ0 the vortensity at the initial location of the planet. In the case where the planet migrates in the direction set by the vortensity-related horseshoe drag, the vortensity deficit is positive and this yields a positive feedback on migration, whereas if the planet migrates in the opposite direction to that set by the corotation torque, the vortensity deficit is negative and this gives rise to a negative feedback on migration (Paardekooper 2014).","Citation Text":["Baruteau & Masset 2008"],"Citation Start End":[[2778,2800]]} {"Identifier":"2017AandA...608A.120A__Bertin_&_Arnouts_(1996)_Instance_1","Paragraph":"Standard data reduction was applied to the data taken with HIPO (red and blue) and FPI+. This includes bias and dark subtraction, and in the case of FPI+ also flat field correction. For FLITECAM we did not acquire bias frames, as bias contributions are generally very low for this type of NIR detector array. Furthermore, it is complicated and time consuming to obtain a reliable flat field on such a narrow band filter as the 1.9 μm Paschen-α continuum filter. Since it was not possible to take long enough exposures during this campaign, we used K-band flat fields taken on the same flight before our observation run, which, however, did not improve the photometric precision significantly. Similarly, dark subtraction did not show any improvement in photometric precision. Additionally, we corrected for the sky background using dithered images taken during the observation run. Stars were detected with the Source Extractor by Bertin & Arnouts (1996). Aperture photometry was applied using Image Reduction and Analysis Facility’s (IRAF Tody 1993) DAOPHOT (Stetson 1987) using circular apertures. The optimal aperture radius with the lowest noise level was found to be six pixels for FLITECAM and 12 pixel for HIPO and FPI+. As part of the DAOPHOT routine, an annulus around the target was used to estimate the sky background in each exposure. Next to GJ 1214, we extracted the light curves of two additional bright stars within our field of view (see Table 1 and Fig. 1). To identify stars in the images we calculated a rough astrometric solution for each image using data provided by Astrometry.net (Barron et al. 2008). In the FLIPO setup SOFIA does not provide an image rotator to compensate field rotation during long integrations. This introduces a rotation of the images over time. Due to SOFIA’s unique setup, the telescope must periodically undergo so-called “line-of-sight (LOS) rewinds”. The required frequency of LOS rewinds depends on the rate of field rotation experienced by the target, which is a complex function of the position of the target in the sky relative to that of the aircraft heading. These need to be carefully timed with regard to the transit observation, to not interfere with, for example, ingress or egress. While we kept the target star, GJ 1214, in boresight, the comparison stars moved over the CCD due to this field rotation. This is one of the main factors introducing systematic noise and limiting the photometric precision of the instrument and is another reason why reliable flat fields are crucial for this kind of time series observation. After comparing the light curves, the brighter star was selected as comparison star to correct for first-order systematic effects present in all light curves. ","Citation Text":["Bertin & Arnouts (1996)"],"Citation Start End":[[931,954]]} {"Identifier":"2017AandA...608A.12Barron_et_al._2008_Instance_1","Paragraph":"Standard data reduction was applied to the data taken with HIPO (red and blue) and FPI+. This includes bias and dark subtraction, and in the case of FPI+ also flat field correction. For FLITECAM we did not acquire bias frames, as bias contributions are generally very low for this type of NIR detector array. Furthermore, it is complicated and time consuming to obtain a reliable flat field on such a narrow band filter as the 1.9 μm Paschen-α continuum filter. Since it was not possible to take long enough exposures during this campaign, we used K-band flat fields taken on the same flight before our observation run, which, however, did not improve the photometric precision significantly. Similarly, dark subtraction did not show any improvement in photometric precision. Additionally, we corrected for the sky background using dithered images taken during the observation run. Stars were detected with the Source Extractor by Bertin & Arnouts (1996). Aperture photometry was applied using Image Reduction and Analysis Facility’s (IRAF Tody 1993) DAOPHOT (Stetson 1987) using circular apertures. The optimal aperture radius with the lowest noise level was found to be six pixels for FLITECAM and 12 pixel for HIPO and FPI+. As part of the DAOPHOT routine, an annulus around the target was used to estimate the sky background in each exposure. Next to GJ 1214, we extracted the light curves of two additional bright stars within our field of view (see Table 1 and Fig. 1). To identify stars in the images we calculated a rough astrometric solution for each image using data provided by Astrometry.net (Barron et al. 2008). In the FLIPO setup SOFIA does not provide an image rotator to compensate field rotation during long integrations. This introduces a rotation of the images over time. Due to SOFIA’s unique setup, the telescope must periodically undergo so-called “line-of-sight (LOS) rewinds”. The required frequency of LOS rewinds depends on the rate of field rotation experienced by the target, which is a complex function of the position of the target in the sky relative to that of the aircraft heading. These need to be carefully timed with regard to the transit observation, to not interfere with, for example, ingress or egress. While we kept the target star, GJ 1214, in boresight, the comparison stars moved over the CCD due to this field rotation. This is one of the main factors introducing systematic noise and limiting the photometric precision of the instrument and is another reason why reliable flat fields are crucial for this kind of time series observation. After comparing the light curves, the brighter star was selected as comparison star to correct for first-order systematic effects present in all light curves. ","Citation Text":["Barron et al. 2008"],"Citation Start End":[[1605,1623]]} {"Identifier":"2016MNRAS.462.2777G__Draine_&_Salpeter_1979_Instance_1","Paragraph":"Dust grains are modelled using Lagrangian tracer particles, where each simulated particle represents a collection of dust grains with similar properties and motions. Trajectories of the particles are integrated using the fully implicit method of Bai & Stone (2010), which we have incorporated into the VL integrator in Athena. In a Cartesian coordinate system, Athena solves an equation of motion for each particle given by\n\n(12)\n\n\\begin{equation}\n\\frac{{\\rm d} {{\\boldsymbol v}_i}}{{\\rm d}t} = -\\frac{{{\\boldsymbol v}_i} - {\\boldsymbol u}}{t_{\\rm stop}},\n\\end{equation}\n\nwith ${{\\boldsymbol v}_i}$ the velocity vector of particle i, ${\\boldsymbol u}$ the local gas velocity vector, and tstop the particle stopping time due to gas drag. Neglecting grain charges and assuming only pure hydrogen gas, the (collisional) drag law is given by (Draine & Salpeter 1979)\n\n(13)\n\n\\begin{equation}\n\\frac{{\\rm d} {\\boldsymbol v}_i}{{\\rm d}t} \\approx -\\frac{2 \\pi a^2 n k_{\\rm B} T G_0(s)}{(4\/3)\\pi \\rho _{\\rm d} a^3},\n\\end{equation}\n\nwith\n\n(14)\n\n\\begin{equation}\nG_0(s) \\approx \\frac{8 s}{3 \\sqrt{\\pi }} \\left(1 + \\frac{9\\pi }{64} s^2\\right)^{1\/2}\n\\end{equation}\n\nand\n\n(15)\n\n\\begin{equation}\ns \\equiv \\left(\\frac{m_{\\rm H} {\\boldsymbol v}_{\\rm rel}^2}{2 k_{\\rm B} T}\\right)^{1\/2},\n\\end{equation}\n\nwhere a is the dust grain radius, kB is the Boltzmann constant, T is the temperature of the gas, n is the gas number density, ρd is the internal density of the dust (which we treat as constant at ρd = 3.0 g cm−3), mH is the mass of hydrogen, and ${\\boldsymbol v}_{\\rm rel} \\equiv {{\\boldsymbol v}_i} - {\\boldsymbol u}$ is the relative velocity difference between the dust and gas. The stopping distance is evaluated as\n\n(16)\n\n\\begin{equation}\nt_{\\rm stop} = \\frac{\\sqrt{\\pi }}{2\\sqrt{2}} \\frac{a \\rho _{\\rm d}}{n \\sqrt{m_{\\rm H} k_{\\rm B} T}} \\left(1 + \\frac{9\\pi m_{\\rm H}}{128 k_{\\rm B} T} {\\boldsymbol v}^2_{\\rm rel}\\right)^{-1\/2}.\n\\end{equation}\n\nThe gas properties (n, T, ${\\boldsymbol u}$) at each particle's location are calculated from nearby grid points using a triangular-shaped cloud (TSC) interpolation scheme (Hockney & Eastwood 1988). There is no momentum feedback from the particles on the gas.","Citation Text":["Draine & Salpeter 1979"],"Citation Start End":[[839,861]]} {"Identifier":"2020MNRAS.497..829F__McKee_&_Tan_2008_Instance_1","Paragraph":"The bottom panel of Fig. 9 shows the mass accretion histories for Z = 10−2 (-2Sol), 10−1, (-1Sol_from-2Sol), and Z⊙ (Sol_from-2Sol), starting from the envelope structure of Z = 10−2 Z⊙. In the early phase of M* ≲ 100 M⊙, while radiative feedback is still weak, the accretion histories are mostly determined by the initial condition and very similar to each other. At later time, radiative feedback starts operating and the accretion history depends on the metallicity in a way that the final mass is lower, or the feedback is stronger, at lower metallicities. This metallicity dependence comes from the dust attenuation of ionizing photons, which can be seen in the following analytic argument. The photoionization feedback quenches the accretion by the photoevaporation of an accretion disc, which proceeds most efficiently near the gravitational radius\n(19)$$\\begin{eqnarray*}\r\nr_{\\rm g} &=& \\frac{GM_{*}}{c_{\\rm i}^2} \\nonumber \\\\\r\n&\\simeq & 1.1 \\times 10^3 ~{\\rm au} \\left(\\frac{M_*}{500~\\mathrm{ M}_{\\odot }} \\right)\r\n\\end{eqnarray*}$$(e.g. Hollenbach et al. 1994; McKee & Tan 2008), where ci is the sound speed of the ionized gas for which we assume T = 3 × 104 K. Equations (15) and (19) indicate that the gravitational radius is located outside the dust destruction front and thus the ionizing photons around the gravitational radius is attenuated by dust grains. Using the disc surface density at r ∼ rg set by the ionization balance,\n(20)$$\\begin{eqnarray*}\r\nn_0 &=& \\left(\\frac{3 S_*}{4 \\pi r_{\\rm g}^3 \\alpha _{\\rm B}} \\right)^{1\/2} \\nonumber \\\\\r\n&\\simeq & 2 \\times 10^{7} ~{\\rm cm^{-3}} \\left(\\frac{S_*}{10^{51} ~{\\rm s^{-1}}} \\right)^{1\/2} \\left(\\frac{M_*}{500~\\mathrm{ M}_{\\odot }} \\right)^{-3\/2},\r\n\\end{eqnarray*}$$where S* is the stellar emissivity of ionizing photons, we find the optical depth from the star to the gravitational radius,\n(21)$$\\begin{eqnarray*}\r\n\\tau _{\\rm d} &=& \\rho \\kappa _{\\rm d} r_{\\rm g} \\nonumber \\\\\r\n&=& 3.0 \\left(\\frac{S_*}{10^{51} ~{\\rm s^{-1}}} \\right)^{1\/2} \\left(\\frac{M_*}{200~M_{\\odot }} \\right)^{-1\/2} \\left(\\frac{\\kappa _{\\rm d}}{350~{\\rm cm^2 g^{-1}}} \\right) \\nonumber\\\\\r\n&&\\times \\,\\left(\\frac{Z}{10^{-2}~Z_{\\odot }} \\right),\r\n\\end{eqnarray*}$$larger than unity for Z ≳ 10−2 Z⊙, where κd is the dust opacity for Lyman-limit frequency at the solar metallicity, meaning that the photoionizing radiation is substantially attenuated by the dust, especially at higher metallicity. This explains the trend of weaker feedback at higher metallicity seen in Fig. 9. According to recent studies (Tanaka, Tan & Zhang 2017; Kuiper & Hosokawa 2018; Tanaka et al. 2018), the impact of photoionization is significantly diminished by the dust attenuation at the solar metallicity. In fact, in our cases with Z = 0.1 (-1Sol_from-2Sol) and 1 Z⊙ (Sol_from-2Sol), the photoionization effect being disabled by this process, the accretion continues until the star becomes very massive with >300 M⊙ and the radiation-pressure feedback finally shuts off the inflow. In this process, the radiation force by the infrared dust re-emission also contributes in terminating the accretion (see equation 17). In particular, it can also repel the flow coming from the shade of the disc, for which the radiation force by the stellar direct light is ineffective (e.g. Yorke & Bodenheimer 1999; Kuiper et al. 2010b; Kuiper & Yorke 2013). Our results suggest that the metallicity dependence of the radiation-pressure effect is weaker than that of the photoionization owing to the dust attenuation in metal-enriched environments. As a result, the final stellar mass increases with increasing metallicity for Z > 10−2 Z⊙.","Citation Text":["McKee & Tan 2008"],"Citation Start End":[[1086,1102]]} {"Identifier":"2016AandA...591A...7G__Iannuzzi_&_Athanassoula_(2015)_Instance_1","Paragraph":"We scale the maps of NGC 4710 to a system that can be directly compared with the Milky Way bulge and compare the resulting maps with those constructed by Zoccali et al. (2014) based on interpolation of the GIBS survey rotational curves. In this comparison we found that the rotation map of NGC 4710 and the rotation map of the Milky Way bulge show a remarkable similarity. Although the velocity dispersion map of the bulge of NGC 4710 appears noisier than that of the Milky Way bulge, owing to the way the maps are constructed, we see that the velocity dispersion map of the Milky Way bulge is more vertically elongated in the centre than in the velocity dispersion map of NGC 4710. We see a similar change in the velocity dispersion maps constructed using different bar orientation angles in the simulation from Cole et al. (2014). This is also in good agreement with the features identified in the LOS kinematic maps of BP bulges modelled by Iannuzzi & Athanassoula (2015). We thus suggest that central increase in the velocity dispersion profile of the Milky Way bulge can be partially the consequence of the Milky Way bar and BP bulge viewing angle of 27° with respect to the Sun-Galactic centre LOS. However, a comparison of the rotation and velocity dispersion curves at different heights from the plane, used by Zoccali et al. (2014) to obtain the rotation maps, are very similar to those of the bulge of NGC 4710. These 1D rotation profiles are also in good agreement with the simulation of a galaxy hosting a pure BP bulge. The differences identified between the inner regions of the σ maps of the Milky Way and NGC 4710 are not seen in the 1D curves. This suggests that the vertical elongation observed in the central region of the σ map of the Milky Way bulge could be an artefact from the plane interpolation method to account for the σ peak observed at b = −2. Instead, the σ peak in the Milky Way bulge would be limited to Galactic latitudes | b | 2 (~0.28 kpc). ","Citation Text":["Iannuzzi & Athanassoula (2015)"],"Citation Start End":[[944,974]]} {"Identifier":"2016AandA...591A...Zoccali_et_al._(2014)_Instance_1","Paragraph":"We scale the maps of NGC 4710 to a system that can be directly compared with the Milky Way bulge and compare the resulting maps with those constructed by Zoccali et al. (2014) based on interpolation of the GIBS survey rotational curves. In this comparison we found that the rotation map of NGC 4710 and the rotation map of the Milky Way bulge show a remarkable similarity. Although the velocity dispersion map of the bulge of NGC 4710 appears noisier than that of the Milky Way bulge, owing to the way the maps are constructed, we see that the velocity dispersion map of the Milky Way bulge is more vertically elongated in the centre than in the velocity dispersion map of NGC 4710. We see a similar change in the velocity dispersion maps constructed using different bar orientation angles in the simulation from Cole et al. (2014). This is also in good agreement with the features identified in the LOS kinematic maps of BP bulges modelled by Iannuzzi & Athanassoula (2015). We thus suggest that central increase in the velocity dispersion profile of the Milky Way bulge can be partially the consequence of the Milky Way bar and BP bulge viewing angle of 27° with respect to the Sun-Galactic centre LOS. However, a comparison of the rotation and velocity dispersion curves at different heights from the plane, used by Zoccali et al. (2014) to obtain the rotation maps, are very similar to those of the bulge of NGC 4710. These 1D rotation profiles are also in good agreement with the simulation of a galaxy hosting a pure BP bulge. The differences identified between the inner regions of the σ maps of the Milky Way and NGC 4710 are not seen in the 1D curves. This suggests that the vertical elongation observed in the central region of the σ map of the Milky Way bulge could be an artefact from the plane interpolation method to account for the σ peak observed at b = −2. Instead, the σ peak in the Milky Way bulge would be limited to Galactic latitudes | b | 2 (~0.28 kpc). ","Citation Text":["Zoccali et al. (2014)"],"Citation Start End":[[154,175]]} {"Identifier":"2016AandA...591A...Zoccali_et_al._(2014)_Instance_2","Paragraph":"We scale the maps of NGC 4710 to a system that can be directly compared with the Milky Way bulge and compare the resulting maps with those constructed by Zoccali et al. (2014) based on interpolation of the GIBS survey rotational curves. In this comparison we found that the rotation map of NGC 4710 and the rotation map of the Milky Way bulge show a remarkable similarity. Although the velocity dispersion map of the bulge of NGC 4710 appears noisier than that of the Milky Way bulge, owing to the way the maps are constructed, we see that the velocity dispersion map of the Milky Way bulge is more vertically elongated in the centre than in the velocity dispersion map of NGC 4710. We see a similar change in the velocity dispersion maps constructed using different bar orientation angles in the simulation from Cole et al. (2014). This is also in good agreement with the features identified in the LOS kinematic maps of BP bulges modelled by Iannuzzi & Athanassoula (2015). We thus suggest that central increase in the velocity dispersion profile of the Milky Way bulge can be partially the consequence of the Milky Way bar and BP bulge viewing angle of 27° with respect to the Sun-Galactic centre LOS. However, a comparison of the rotation and velocity dispersion curves at different heights from the plane, used by Zoccali et al. (2014) to obtain the rotation maps, are very similar to those of the bulge of NGC 4710. These 1D rotation profiles are also in good agreement with the simulation of a galaxy hosting a pure BP bulge. The differences identified between the inner regions of the σ maps of the Milky Way and NGC 4710 are not seen in the 1D curves. This suggests that the vertical elongation observed in the central region of the σ map of the Milky Way bulge could be an artefact from the plane interpolation method to account for the σ peak observed at b = −2. Instead, the σ peak in the Milky Way bulge would be limited to Galactic latitudes | b | 2 (~0.28 kpc). ","Citation Text":["Zoccali et al. (2014)"],"Citation Start End":[[1319,1340]]} {"Identifier":"2022ApJ...933..219Y__Gaelzer_et_al._2003_Instance_1","Paragraph":"The third and higher harmonic plasma emissions, at the frequency of multiples of the local plasma frequency, were also observed in SRBs (Takakura & Yousef 1974; Cairns 1986; Reiner & MacDowall 2019). Various schemes have been proposed to explain the formation of higher harmonic plasma emission. Zlotnik (1978) put forward that the third harmonic emission H\n3 is generated by the coalescence process of the Langmuir waves and the harmonic emission H, i.e., L + H → H\n3. Cairns (1988) generalized this idea to explain higher harmonics of transverse wave emissions, claiming that nth harmonic waves H\n\nn\n could be generated by a coalescence of beam-generated Langmuir waves L and adjacent transverse waves H\n\nn−1, i.e., L + H\n\nn−1 → H\n\nn\n. An alternative way for the generation of harmonic transverse waves would be an interaction of Langmuir waves L and harmonic electrostatic waves L\n\nn−1, i.e., L + L\n\nn−1 → H\n\nn\n (Gaelzer et al. 2003; Yi et al. 2007). Ziebell et al. (2015) numerically solved the weak-turbulence equations and theoretically demonstrate the process of multiple-harmonic plasma emission, including the nonlinear conversion from Langmuir turbulence to electromagnetic radiation. Rhee et al. (2009), Ziebell et al. (2015), Yao et al. (2021) investigated both schemes of multiple-harmonic plasma emissions by means of Particle-In-Cell (PIC) code simulations. They found that Cairns (1988)'s scheme can qualitatively explain the third and fourth harmonic emissions while Yi et al. (2007)'s theory is appropriate to explain the simultaneously generated harmonics of electrostatic waves. PIC code simulations of electron beams demonstrated that fundamental transverse waves at the plasma frequency can be generated because of the wave–wave interaction processes involving ion-acoustic waves (Thurgood & Tsiklauri 2015; Henri et al. 2019). The PIC simulations of ring-beam EVDFs by Zhou et al. (2020) also provided evidence for the generation of the second and third harmonic emission via wave–wave interactions. Annenkov et al. (2019) used PIC code simulations to describe localized beams and found that the emissions at harmonics of the plasma frequency can be generated due to an antenna mechanism.","Citation Text":["Gaelzer et al. 2003"],"Citation Start End":[[916,935]]} {"Identifier":"2022ApJ...936...78M__Li_et_al._2018_Instance_1","Paragraph":"Measurements of the scale length (h\n\nR\n) and scale height (h\n\nZ\n) are important to trace the structure, size, mass distribution, and radial luminosity profile of the Galactic disk components (e.g., Dehnen & Binney 1998). In order to calculate h\n\nR\n and h\n\nZ\n of our Atari disk sample, we solve the fundamental collisionless Boltzmann equation of axisymmetric systems, which is expressed as follows (see Equation (4.12) in Binney & Tremaine 2008):\n10\n\n\n\n∂f∂t+vR∂f∂R+vϕR2∂f∂ϕ+vz∂f∂z−∂Φ∂R−vϕ2R3∂f∂vR−∂Φ∂ϕ∂f∂vϕ−∂Φ∂z∂f∂vz=0,\n\nwhere f is the number of objects in a small volume and Φ is the gravitational potential. It is then convenient to derive the Jeans equation from the Boltzmann equation in the radial and Z-component directions as follows (see Equation (9) in Gilmore et al. 1989):\n11\n\n\n\nρKR=1R∂(RρσVR2)∂R+∂(ρσVR,Z2)∂Z−ρσVϕ2R−ρRVϕ¯2\n\n\n\n12\n\n\n\nρKZ=∂(ρσVZ2)∂Z+1R∂(RρσVR,Z2)∂R,\n\nwhere ρ(R, Z) is the space density of the stars in the thick disk and K\n\nR\n = \n\n\n\n∂ϕ∂R\n\n and K\n\nZ\n = \n\n\n\n∂ϕ∂Z\n\n are the derivatives of the potential. Assuming an exponential density profile, the radial Jeans equation can be rewritten as follows (Li et al. 2018):\n13\n\n\n\nσVϕ2σVR2−2+2RhR−Vc2−Vϕ¯2σVR2+σVZ2σVR2=0,\n\nwhere h\n\nR\n is the scale length. By substituting our calculated velocity dispersions from the Atari disk sample, within ≈3 kpc of the Sun in the cylindrical R coordinate and ≈2 kpc above or below the Galactic plane (6347 stars), into Equation (13), we obtain a radial scale length of h\n\nR\n = 2.48 kpc. Calculating the scale length using different metallicity bins shows a small increase from 2.38 kpc among the higher-metallicity stars up to 2.91 kpc for the low-metallicity stars. The results are detailed in Table 3. In general, these results point to the Atari disk being comparable in size in the radial direction to the thick and thin disk. For reference, the scale length of the canonical thick disk has been measured as 2.0 kpc (Bensby et al. 2011), 2.2 kpc (Carollo et al. 2010), and 2.31 kpc (Sanders & Binney 2015), although larger values have also been reported previously (Chiba & Beers 2000; de Jong et al. 2010). Thin disk values refer to an overall similar spatial distribution, although it is likely somewhat more extended (h\n\nR\n > 3.0 kpc; e.g., Bensby et al. 2011; Sanders & Binney 2015). See Table 2 for further details.","Citation Text":["Li et al. 2018"],"Citation Start End":[[1123,1137]]} {"Identifier":"2021ApJ...922...22L__Feng_&_Dai_2011_Instance_1","Paragraph":"Our fitting is performed based on the Markov Chain Monte Carlo (MCMC) method to produce posterior predictions for the model parameters. The MCMC method is widely used in finding the best set of parameters for a specified model, e.g., GRB 080413B (Geng et al. 2016); GRBs 100418A, 100901A, 120326A, and 120404A (Laskar et al. 2015). In our work, fitting the afterglows of the four bursts with the MCMC method is to test whether or not the late simultaneous bumps followed by a steep decay can be explained with an external-forward shock in a free-to-shocked wind environment. The posterior probability density functions for the physical parameters, i.e., Ek,iso,on, Γ0, θc, θjet\/θc, θv\/θc, p, ϵe, ϵB, A*, and Rtr, are presented in Figure 6, where only the fitting result of GRB 120326A is shown as an example. The optimal result from MCMC fitting is shown in Figure 5 with the blue line (XRT) and red line (optical), and the obtained parameters at the 1σ confidence level are reported in Table 1, where the values of the transition radius \n\n\n\n\n\n\nR\n\n\ntr\n\n\n\n\n (i.e., 1.05 × 1017, 1.91 × 1017, 3.98 ×1017, and 6.31 × 1016 cm for GRBs 120326A, 100901A, 100814A, and 120404A, respectively) are consistent with those found in other bursts (e.g., Ramirez-Ruiz et al. 2001; Kong et al. 2010; Feng & Dai 2011; Li et al. 2020). It can be found that both the X-ray afterglow and the optical afterglow of these bumps can be well modeled with an external-forward shock in a free-to-shocked wind environment.\n\n1.\nThe theoretical light curves do not well fit the transition behavior from the free-wind phase to the shocked-wind phase in the afterglows of GRB 120326A. This may imply that the density jump factor ξ from the free-wind medium to the shocked-wind medium may be less than 4, i.e., ξ 4. Figure 1 reveals that the external-forward shock propagating in a shocked-wind environment can yield a plateau before the late simultaneous bumps in the case of θv = 4θc. Then, we try to fit the afterglows of GRB 120326A with the emission of the external-forward shock propagating in a homogeneous medium, where the priors of \n\n\n\n\n\nlog\n10\n\n(\n\nE\n\nk\n,\niso\n,\non\n\n\n\n\nerg\n\n-\n1\n\n\n)\n\n\n, \n\n\n\n\n\n\nlog\n\n\n10\n\n\n\n\nΓ\n\n\n0\n\n\n\n\n, θc, θjet\/θc, θv\/θc, p, \n\n\n\n\n\n\nlog\n\n\n10\n\n\n\n\nϵ\n\n\ne\n\n\n\n\n, \n\n\n\n\n\n\nlog\n\n\n10\n\n\n\n\nϵ\n\n\nB\n\n\n\n\n, and \n\n\n\n\n\n\nlog\n\n\n10\n\n\n\n\nn\n\n\n0\n\n\n\n\n are set as a uniform distribution in the range of (52, 55), (1.5, 3.0), (0.3, 8.0), (2.5, 4.5), (0.0, 8.0), (2.1, 2.9), (−3.2, −0.5), (−6.5, −2.0), and (0.0, 1.7) in our MCMC fittings, respectively. However, no well-fitting result is found. The fitting result with minimum reduced χ2 is shown with dashed lines in the top left panel of Figure 5. It can be found that the early plateau of GRB 120326A could not be well fitted based on the emission of the external-forward shock in a homogeneous medium.\n\n\n2.\nThere seems to be a plateau at tobs ∼ 600 s in the optical afterglow of GRB 100814A, which may indicate an energy injection into the external shock. If so, our model could not well describe the afterglows of GRB 100814A in its early phase. This may be the reason for the deviation in our theoretical results relative to the observations in the early phase. In addition, the X-ray and optical afterglows of GRB 100814A show achromatic behavior, which could not be explained only by our scenario (i.e., an off-core observed structured jet propagating into a free-to-shocked wind environment) since the appearance of the late simultaneous bump\/plateau in our scenario is achromatic. Other emission rather than that of the external-forward shock may contribute to the long X-ray shallow decay. In addition, our model could not well describe the X-ray emission at tobs ≳ 3 × 105 s in GRB 100901A, which seems to be another component in this phase.\n\n\n3.\nThe fitting result of GRB 120404A shows that this burst is observed in the core. Based on the fitting result of this burst, the deceleration radius of the (0, 0) jet can be estimated and is 2.43 × 1016 cm, which is at around the transition radius \n\n\n\n\n\n\nR\n\n\ntr\n\n\n=\n6.31\n×\n\n\n10\n\n\n16\n\n\n\n\n cm of this burst.\n\n\n","Citation Text":["Feng & Dai 2011"],"Citation Start End":[[1283,1298]]} {"Identifier":"2015AandA...583A..52M__Ma_&_Scott_2013_Instance_1","Paragraph":"For the cosmic variance term, any two samples are correlated so the off-diagonal\n element of Gij\n (i ≠\n j) is non-zero. But for the measurement noise term,\n small scale, and intrinsic dispersion, the two samples are not correlated, so they only\n contribute to the diagonal term in the Gij matrix. The first\n term is the real space velocity correlation function, which is related to the matter\n power spectrum in Fourier space (Watkins et al.\n 2009; Ma & Scott 2013),\n (10)\\begin{eqnarray} \\bigl\\langle \\bigl(\\hat{{\\vec r}}_{i} \\cdot {\\vec v}({\\vec r}_{i})\\bigr) \\bigl(\\hat{{\\vec r}}_{j} \\cdot {\\vec v}({\\vec r}_{j})\\bigr) \\bigr\\rangle =\\frac{H^{2}_{0}f^{2}(z=0)}{2 \\pi^{2}}\\int \\mathrm{\\ } \\der k \\mathrm{\\ } P(k) \\mathrm{\\ } F_{ij}(k), \\label{vel_rnrm1} \\end{eqnarray}\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nr\n\n\nˆ\n\n\ni\n\n·\n\n\nv\n\n\n(\n\n\n\nr\n\n\n\ni\n\n\n)\n\n\n\n\n\n\n\n\n\n\n\n\n\nr\n\n\nˆ\n\n\nj\n\n·\n\n\nv\n\n\n(\n\n\n\nr\n\n\n\nj\n\n\n)\n\n\n\n\n\n\n\n\n\n\n=\n\n\n\n\n\n\nH\n\n0\n\n\n2\n\n\n\nf\n\n2\n\n\n(\nz\n=\n0\n)\n\n\n2\n\nπ\n\n2\n\n\n\n\n\n\n\n\n∫\n\n\n\n\nd\nk\n\n\n\nP\n(\nk\n)\n\n\n\n\nF\n\nij\n\n\n(\nk\n)\n,\n\n\n\n\n\n\n\n\n\n\nwhere P(k) is\n the matter power spectrum that we output from public code camb (Lewis et al. 2000). The f(z) =\n dlnD\/ dlna is\n the growth rate function that characterizes how fast the structures grow at different\n epochs of the Universe. Since the Cosmicflows-2  samples peak at the redshift\n z ≃\n 0.0167 (lower panel of Fig. 2),\n we use the zero-redshift growth function \\hbox{$f(z=0)=\\Omega_{\\rm m}^{0.55}$}\nf\n(\nz\n=\n0\n)\n=\n\nΩ\nm\n0.55\n\n (Watkins\n et al. 2009; Ma & Scott 2013) in Eq.\n (10). In the future, if the survey\n probes deeper region of the space, one should use the corresponding growth function\n f(z) in Eq. (10), so that the joint constraints on\n f(z)σ8\n can be obtained, which constitutes a sensitive test of modify gravity models (Hudson & Turnbull 2012; Planck Collaboration XIII 2015). ","Citation Text":["Ma & Scott 2013"],"Citation Start End":[[543,558]]} {"Identifier":"2015AandA...583A..52M__Ma_&_Scott_2013_Instance_2","Paragraph":"For the cosmic variance term, any two samples are correlated so the off-diagonal\n element of Gij\n (i ≠\n j) is non-zero. But for the measurement noise term,\n small scale, and intrinsic dispersion, the two samples are not correlated, so they only\n contribute to the diagonal term in the Gij matrix. The first\n term is the real space velocity correlation function, which is related to the matter\n power spectrum in Fourier space (Watkins et al.\n 2009; Ma & Scott 2013),\n (10)\\begin{eqnarray} \\bigl\\langle \\bigl(\\hat{{\\vec r}}_{i} \\cdot {\\vec v}({\\vec r}_{i})\\bigr) \\bigl(\\hat{{\\vec r}}_{j} \\cdot {\\vec v}({\\vec r}_{j})\\bigr) \\bigr\\rangle =\\frac{H^{2}_{0}f^{2}(z=0)}{2 \\pi^{2}}\\int \\mathrm{\\ } \\der k \\mathrm{\\ } P(k) \\mathrm{\\ } F_{ij}(k), \\label{vel_rnrm1} \\end{eqnarray}\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nr\n\n\nˆ\n\n\ni\n\n·\n\n\nv\n\n\n(\n\n\n\nr\n\n\n\ni\n\n\n)\n\n\n\n\n\n\n\n\n\n\n\n\n\nr\n\n\nˆ\n\n\nj\n\n·\n\n\nv\n\n\n(\n\n\n\nr\n\n\n\nj\n\n\n)\n\n\n\n\n\n\n\n\n\n\n=\n\n\n\n\n\n\nH\n\n0\n\n\n2\n\n\n\nf\n\n2\n\n\n(\nz\n=\n0\n)\n\n\n2\n\nπ\n\n2\n\n\n\n\n\n\n\n\n∫\n\n\n\n\nd\nk\n\n\n\nP\n(\nk\n)\n\n\n\n\nF\n\nij\n\n\n(\nk\n)\n,\n\n\n\n\n\n\n\n\n\n\nwhere P(k) is\n the matter power spectrum that we output from public code camb (Lewis et al. 2000). The f(z) =\n dlnD\/ dlna is\n the growth rate function that characterizes how fast the structures grow at different\n epochs of the Universe. Since the Cosmicflows-2  samples peak at the redshift\n z ≃\n 0.0167 (lower panel of Fig. 2),\n we use the zero-redshift growth function \\hbox{$f(z=0)=\\Omega_{\\rm m}^{0.55}$}\nf\n(\nz\n=\n0\n)\n=\n\nΩ\nm\n0.55\n\n (Watkins\n et al. 2009; Ma & Scott 2013) in Eq.\n (10). In the future, if the survey\n probes deeper region of the space, one should use the corresponding growth function\n f(z) in Eq. (10), so that the joint constraints on\n f(z)σ8\n can be obtained, which constitutes a sensitive test of modify gravity models (Hudson & Turnbull 2012; Planck Collaboration XIII 2015). ","Citation Text":["Ma & Scott 2013"],"Citation Start End":[[1652,1667]]} {"Identifier":"2016ApJ...832...65Z__Pontin_et_al._2016_Instance_1","Paragraph":"Solar flares are one of the most spectacular activities in the solar system. Up to 1029–1032 erg magnetic free energy is impulsively released, accompanied by rapid increases of emissions in various wavelengths (Shibata & Magara 2011). It is generally believed that magnetic reconnection plays a key role in the reconfiguration of magnetic field lines and the conversion of magnetic energy into kinetic and thermal energies of plasma (Forbes & Acton 1996; Priest & Forbes 2000). In the context of the standard solar flare model (Carmichael 1964; Sturrock 1966; Hirayama 1974; Kopp & Pneuman 1976), accelerated nonthermal electrons propagate downward and heat the chromosphere, forming bright flare ribbons in the Hα, Ca ii H, ultraviolet (UV), and extreme-ultraviolet (EUV) wavelengths. The flare ribbons have diverse shapes, with two parallel flare ribbons (PFRs) being the most commonplace (Li & Zhang 2015). Sometimes, circular flare ribbons (CFRs) appear accompanied by remote brightenings, which are generally believed to be associated with a magnetic null point (\n\n\n\n\n\n) and a dome-like spine–fan topology (Masson et al. 2009; Zhang et al. 2012; Pontin et al. 2016). More complex flare ribbons have also been observed (Joshi et al. 2015). Apart from the localized heating, hard X-ray (HXR) emissions are generated via Coulomb collisions (Brown 1971). If open magnetic field lines are involved, it is likely that the nonthermal electrons at speeds of 0.06–0.25c (c is the speed of light) escape from the Sun into interplanetary space and generate type III radio bursts with frequencies ranging from 0.2 to hundreds of MHz (Dulk et al. 1987; Aschwanden et al. 1995; Zhang et al. 2015). Sometimes, the HXR and radio emissions of a flare show quasi-periodic pulsations (QPPs), with their periods ranging from milliseconds (Tan et al. 2010) through a few seconds (Kliem et al. 2000; Asai et al. 2001; Ning et al. 2005; Nakariakov et al. 2010; Hayes et al. 2016) to several minutes (Ofman & Sui 2006; Nakariakov & Melnikov 2009; Sych et al. 2009; Ning 2014). So far, QPPs have been extensively explored using both imaging (Su et al. 2012a, 2012b) and spectral observations (Mariska 2005). Li et al. (2015b) studied the X1.6 flare on 2014 September 10. Four-minute QPPs are evident not only in the HXR, EUV, UV, and radio light curves, but also in the temporal evolutions of the Doppler velocities and line widths of the C i, O iv, Si iv, and Fe xxi lines. Brosius & Daw (2015) studied the M7.3 flare on 2014 April 18. The chromospheric and transition region line emissions show quasi-periodic intensity and velocity fluctuations with periods of ∼3 minutes during the first four peaks and ∼1.5 minutes during the last four peaks.","Citation Text":["Pontin et al. 2016"],"Citation Start End":[[1151,1169]]} {"Identifier":"2021ApJ...910L..21M__Özel_&_Freire_2016_Instance_1","Paragraph":"Figures 2 and 3 demonstrate that the GW alert system is capable of providing GW alerts before merger, but they do not consider the prospects for detection from an astrophysical source population. We generate a population of simulated BNS signals, henceforth referred to as injections, using the TaylorF2 (Sathyaprakash & Dhurandhar 1991; Blanchet et al. 1995, 2005; Buonanno et al. 2009) waveform model. Both source-frame component masses are drawn from a Gaussian distribution between 1.0 M⊙ m1, m2 2.0 M⊙ with mean mass of 1.33 M⊙ and standard deviation of 0.09 M⊙, modeled after observations of galactic BNSs (Özel & Freire 2016).40\n\n40\nNote that if GW190425 is a BNS, then galactic measurements are not representative of neutron star masses.\n The neutron stars in the population are nonspinning, motivated by the low spins of BNSs expected to merge within a Hubble time (Burgay et al. 2003; Zhu et al. 2018). The signals are distributed uniformly in comoving volume up to a redshift of z = 0.2. We consider a network of four GW detectors: LIGO-Hanford, LIGO-Livingston, Virgo, and KAGRA at their projected O4 sensitivities.41\n\n41\n\nhttps:\/\/dcc.ligo.org\/LIGO-T2000012\/public\n\n We simulate the results of an early warning matched-filtering pipeline by considering six different discrete frequency cutoffs: 29, 32, 38, 49, 56, and 1024 Hz to analyze signal recovery at (approximately) 58, 44, 28, 14, 10, and 0 s before merger, motivated by Sachdev et al. (2020). We calculate the network S\/N of each injection at each frequency cutoff and consider the events that pass an S\/N cutoff of 12.0 as “detected.” We then calculate the sky posteriors for each of the detected signals by using BAYESTAR (Singer & Price 2016). We use the most recent BNS local merger rate from Abbott et al. (2020b) of \n\n\n\n\n\n to estimate the number of events detected per year in the detector network. In Figure 4(a) we see that our optimistic scenario predicts \n\n\n\n\n\n GCN will be received 1 s before merger per year, while our pessimistic scenario predicts \n\n\n\n\n\n GCN will be received 1 s before merger per year considering the higher end of the BNS rate. Figure 4(b) predicts that ∼9 events will be detected per year, out of which ∼20% (∼1.3%) will be detected 10 s (60 s) before merger. Further, ∼3% of the detectable events (∼1 BNS every 3–4 yr) will be detected 10 s prior to merger and have a localization less than 100 deg2 at O4 sensitivities. This highlights the need for continued latency improvements in advance of O4 to maximize the potential of capturing prompt emission.","Citation Text":["Özel & Freire 2016"],"Citation Start End":[[614,632]]} {"Identifier":"2021ApJ...923...94Z__Sossi_et_al._2018_Instance_1","Paragraph":"Solar system planetary bodies are generally volatile depleted compared to chondritic meteorites (e.g., O’Neill & Palme 2008; Braukmüller et al. 2019). For example, Rb–Sr and K–U are elemental pairs with similar geochemical behaviors, but Rb and K are much more volatile than Sr and U, and Earth has Rb\/Sr and K\/U ratios that are ∼10 times lower than that of Ivuna-like carbonaceous (CI) chondrites (Allègre et al. 2001; Halliday & Porcelli 2001). However, the mechanisms and conditions that led to this relative volatile-element depletion remain ambiguous. The stable isotopes of elements can be fractionated by volatilization processes and the shifts in their isotopic compositions have been applied to understand volatile-element depletion processes (Humayun & Clayton 1995; Luck et al. 2005; Hin et al. 2017; Kato & Moynier 2017b; Pringle & Moynier 2017; Young et al. 2019; Bloom et al. 2020; Hellmann et al. 2021). Cr is a moderately volatile element (Lodders 2003; Wood et al. 2019) that may show a special behavior during volatilization at higher temperatures. Under moderately reducing to oxidizing conditions (fO2 > IW+1), relevant during evaporation processes from magma oceans on planets (Visscher & Fegley 2013), Cr may be present in the gas as oxide species CrO(g), CrO2(g) and CrO3(g) (Chase 1998). Equilibrium isotopic fractionation between these gas phase species and melt will cause enrichment of the lighter Cr isotopes in the condensed phases, in which Cr is either di- or trivalent, relative to the vapor (Sossi et al. 2018). This contrasts with its speciation under more reduced nebular conditions in which Cr may be present as Cr2+ (major; in silicates) or Cr0 (minor; in Fe–Ni metal) in condensed phases and Cr0 in the gas (Grossman et al. 2008), in which case, through either equilibrium or kinetic fractionation, the condensed phase will be enriched in the heavy Cr isotopes. Solids or magmas that evaporated significant quantities of moderately volatile elements such as Zn, K, Rb, or Ga normally show enrichments of heavy isotopes of these elements, both for kinetic and equilibrium isotope fractionation processes (Paniello et al. 2012; Wang & Jacobsen 2016; Kato & Moynier 2017a; Pringle & Moynier 2017). The behavior of Cr during evaporation has been a motivation to apply this element to study the origin of volatile depletion in the Moon and of the eucrite parent body (likely asteroid 4-Vesta) (Sossi et al. 2018; Zhu et al. 2019b). Both lunar samples and HED meteorites from Vesta are enriched in the lighter isotopes of Cr compared to Earth and chondrites. These isotopic enrichments have been interpreted to reflect equilibrium Cr isotope fractionation between melt (reduced, and enriched in CrO) and gas (oxidized, and enriched in CrO2) during evaporation from a magma ocean. Given that at equilibrium, isotopic fractionation scales with 1\/T\n2, the Cr evaporation from the Moon and Vesta was estimated to have occurred under relatively low temperatures (∼2000 K), which in the case of the Moon is comparable to the surface temperature of a lunar magma ocean (Sossi et al. 2018).","Citation Text":["Sossi et al. 2018"],"Citation Start End":[[1525,1542]]} {"Identifier":"2021ApJ...923...94Z__Sossi_et_al._2018_Instance_2","Paragraph":"Solar system planetary bodies are generally volatile depleted compared to chondritic meteorites (e.g., O’Neill & Palme 2008; Braukmüller et al. 2019). For example, Rb–Sr and K–U are elemental pairs with similar geochemical behaviors, but Rb and K are much more volatile than Sr and U, and Earth has Rb\/Sr and K\/U ratios that are ∼10 times lower than that of Ivuna-like carbonaceous (CI) chondrites (Allègre et al. 2001; Halliday & Porcelli 2001). However, the mechanisms and conditions that led to this relative volatile-element depletion remain ambiguous. The stable isotopes of elements can be fractionated by volatilization processes and the shifts in their isotopic compositions have been applied to understand volatile-element depletion processes (Humayun & Clayton 1995; Luck et al. 2005; Hin et al. 2017; Kato & Moynier 2017b; Pringle & Moynier 2017; Young et al. 2019; Bloom et al. 2020; Hellmann et al. 2021). Cr is a moderately volatile element (Lodders 2003; Wood et al. 2019) that may show a special behavior during volatilization at higher temperatures. Under moderately reducing to oxidizing conditions (fO2 > IW+1), relevant during evaporation processes from magma oceans on planets (Visscher & Fegley 2013), Cr may be present in the gas as oxide species CrO(g), CrO2(g) and CrO3(g) (Chase 1998). Equilibrium isotopic fractionation between these gas phase species and melt will cause enrichment of the lighter Cr isotopes in the condensed phases, in which Cr is either di- or trivalent, relative to the vapor (Sossi et al. 2018). This contrasts with its speciation under more reduced nebular conditions in which Cr may be present as Cr2+ (major; in silicates) or Cr0 (minor; in Fe–Ni metal) in condensed phases and Cr0 in the gas (Grossman et al. 2008), in which case, through either equilibrium or kinetic fractionation, the condensed phase will be enriched in the heavy Cr isotopes. Solids or magmas that evaporated significant quantities of moderately volatile elements such as Zn, K, Rb, or Ga normally show enrichments of heavy isotopes of these elements, both for kinetic and equilibrium isotope fractionation processes (Paniello et al. 2012; Wang & Jacobsen 2016; Kato & Moynier 2017a; Pringle & Moynier 2017). The behavior of Cr during evaporation has been a motivation to apply this element to study the origin of volatile depletion in the Moon and of the eucrite parent body (likely asteroid 4-Vesta) (Sossi et al. 2018; Zhu et al. 2019b). Both lunar samples and HED meteorites from Vesta are enriched in the lighter isotopes of Cr compared to Earth and chondrites. These isotopic enrichments have been interpreted to reflect equilibrium Cr isotope fractionation between melt (reduced, and enriched in CrO) and gas (oxidized, and enriched in CrO2) during evaporation from a magma ocean. Given that at equilibrium, isotopic fractionation scales with 1\/T\n2, the Cr evaporation from the Moon and Vesta was estimated to have occurred under relatively low temperatures (∼2000 K), which in the case of the Moon is comparable to the surface temperature of a lunar magma ocean (Sossi et al. 2018).","Citation Text":["Sossi et al. 2018"],"Citation Start End":[[2427,2444]]} {"Identifier":"2021ApJ...923...94Z__Sossi_et_al._2018_Instance_3","Paragraph":"Solar system planetary bodies are generally volatile depleted compared to chondritic meteorites (e.g., O’Neill & Palme 2008; Braukmüller et al. 2019). For example, Rb–Sr and K–U are elemental pairs with similar geochemical behaviors, but Rb and K are much more volatile than Sr and U, and Earth has Rb\/Sr and K\/U ratios that are ∼10 times lower than that of Ivuna-like carbonaceous (CI) chondrites (Allègre et al. 2001; Halliday & Porcelli 2001). However, the mechanisms and conditions that led to this relative volatile-element depletion remain ambiguous. The stable isotopes of elements can be fractionated by volatilization processes and the shifts in their isotopic compositions have been applied to understand volatile-element depletion processes (Humayun & Clayton 1995; Luck et al. 2005; Hin et al. 2017; Kato & Moynier 2017b; Pringle & Moynier 2017; Young et al. 2019; Bloom et al. 2020; Hellmann et al. 2021). Cr is a moderately volatile element (Lodders 2003; Wood et al. 2019) that may show a special behavior during volatilization at higher temperatures. Under moderately reducing to oxidizing conditions (fO2 > IW+1), relevant during evaporation processes from magma oceans on planets (Visscher & Fegley 2013), Cr may be present in the gas as oxide species CrO(g), CrO2(g) and CrO3(g) (Chase 1998). Equilibrium isotopic fractionation between these gas phase species and melt will cause enrichment of the lighter Cr isotopes in the condensed phases, in which Cr is either di- or trivalent, relative to the vapor (Sossi et al. 2018). This contrasts with its speciation under more reduced nebular conditions in which Cr may be present as Cr2+ (major; in silicates) or Cr0 (minor; in Fe–Ni metal) in condensed phases and Cr0 in the gas (Grossman et al. 2008), in which case, through either equilibrium or kinetic fractionation, the condensed phase will be enriched in the heavy Cr isotopes. Solids or magmas that evaporated significant quantities of moderately volatile elements such as Zn, K, Rb, or Ga normally show enrichments of heavy isotopes of these elements, both for kinetic and equilibrium isotope fractionation processes (Paniello et al. 2012; Wang & Jacobsen 2016; Kato & Moynier 2017a; Pringle & Moynier 2017). The behavior of Cr during evaporation has been a motivation to apply this element to study the origin of volatile depletion in the Moon and of the eucrite parent body (likely asteroid 4-Vesta) (Sossi et al. 2018; Zhu et al. 2019b). Both lunar samples and HED meteorites from Vesta are enriched in the lighter isotopes of Cr compared to Earth and chondrites. These isotopic enrichments have been interpreted to reflect equilibrium Cr isotope fractionation between melt (reduced, and enriched in CrO) and gas (oxidized, and enriched in CrO2) during evaporation from a magma ocean. Given that at equilibrium, isotopic fractionation scales with 1\/T\n2, the Cr evaporation from the Moon and Vesta was estimated to have occurred under relatively low temperatures (∼2000 K), which in the case of the Moon is comparable to the surface temperature of a lunar magma ocean (Sossi et al. 2018).","Citation Text":["Sossi et al. 2018"],"Citation Start End":[[3095,3112]]} {"Identifier":"2020ApJ...896..170R__Fèvre_et_al._2019_Instance_1","Paragraph":"The semiforbidden [C iii] λ1907 + C iii] λ1909 doublet (hereafter C iii] λ1909 or C iii]) is one of the strongest nebular emission line features observed in the rest-frame ultraviolet (rest-UV) spectrum of low-metallicity, 12+log(O\/H) ≤ 8.4 (Z 0.5 Z⊙) star-forming galaxies (SFGs) both locally (Garnett et al. 1995; Rigby et al. 2015; Berg et al. 2016, 2019; Senchyna et al. 2017, 2019) and at high redshifts (Fosbury et al. 2003; Erb et al. 2010; Bayliss et al. 2014; Stark et al. 2014, 2015a, 2017; de Barros et al. 2016; Vanzella et al. 2016; Amorín et al. 2017; Laporte et al. 2017; Maseda et al. 2017; Berg et al. 2018; Hutchison et al. 2019; Le Fèvre et al. 2019). The C iii] emission line is frequently observed in gravitationally lensed SFGs at z > 2–6 as the strongest line after Lyα λ1216 emission. Since the Lyα emission at z > 6 is expected to be severely quenched by the increasingly neutral intergalactic medium (IGM), C iii] is emerging as an alternative redshift indicator for galaxies in the reionization era (Stark et al. 2015a, 2017; Ding et al. 2017). At z > 6, the rest-UV spectrum of galaxies is redshifted to the near-infrared (NIR) wavelengths and is accessible to the spectrographs on upcoming facilities (such as the James Webb Space Telescope (JWST) and the >20 m class Extremely Large Telescopes), which will address the key goal of identifying the sources of reionization. In recent years, there has been considerable effort to develop spectral diagnostics involving the C iii] emission line and other UV spectral features (e.g., C iv λλ1548, 1550, He ii λ1640, and O iii] λλ1661, 1666 (hereafter O iii] λ1663 or O iii])) that can be used to understand the nature of the reionizers, their hard ionizing continua, and the physical conditions in their ISM (Feltre et al. 2016; Gutkin et al. 2016; Jaskot & Ravindranath 2016, hereafter JR16; Byler et al. 2018; Nakajima et al. 2018b). The C iii] emission observed at high redshifts is mostly from strongly lensed low-metallicity (0.5 Z⊙), low-mass (1010 M⊙) galaxies with high specific star formation rates (SSFRs ≳ 2 Gyr−1), and their C iii] equivalent widths (EWs) show a broad range: EW(C iii]) ∼ 3–25 Å (Fosbury et al. 2003; Erb et al. 2010; Bayliss et al. 2014; Stark et al. 2014; de Barros et al. 2016; Vanzella et al. 2016; Berg et al. 2018). The composite rest-UV spectra of Lyman-break galaxies at z ∼ 3 (Shapley et al. 2003) and SFGs at z = 1–2.5 (Steidel et al. 2016; Amorín et al. 2017) also reveal the C iii] λ1909 and O iii] λ1663 nebular lines at subsolar metallicities.","Citation Text":["Le Fèvre et al. 2019"],"Citation Start End":[[649,669]]} {"Identifier":"2016MNRAS.458...84A__Kochanek_2014_Instance_1","Paragraph":"While the properties of the SLSN hosts themselves are of interest, they are most diagnostic when compared to other classes of extragalactic transient whose progenitors are better understood. To this end, we employ a comparison sample of LGRB and CCSN3 host galaxies. In principle, CCSNe should trace all core-collapse events, although the mass function means they will be dominated by stars at the lower mass end (∼8 M⊙ to ∼25 M⊙). There also remains a possibility that some very massive stars can undergo core collapse without yielding a LSNe (e.g. Smartt 2009; Ugliano et al. 2012; Kochanek 2014) such that CCSNe samples might only provide a census of lower mass core collapsing stars (e.g. 8 M* 20 M⊙). Indeed, constraints from explosion parameters have shown the majority of CCSNe to be consistent with lower mass progenitors, as opposed to more massive Wolf–Rayet stars (Cano 2013; Lyman et al. 2016) GRBs likely represent a population with rather larger initial masses (Larsson et al. 2007; Raskin et al. 2008). LGRBs are now known to be associated with the core collapse of massive stars, and broad line SN Ic are near ubiquitously associated with low-z events (where such signatures can be seen; Hjorth et al. 2012). When compared to the hosts of CCSNe they are generally smaller and of lower luminosity, consistent with an origin in galaxies of lower metallicity (Fruchter et al. 2006; Svensson et al. 2010). In relatively local examples, where spatially resolved gas phase metallicities can be obtained, these indeed appear to be lower for GRBs than for CCSNe, even in cases where the luminosity of the galaxy is relatively high (i.e. the GRB host galaxies lie off the mass–metallicity relation; Modjaz et al. 2008; Graham & Fruchter 2013). Hence, comparing the hosts of SLSNe to these events allows us to test the large-scale environments of SLSNe against those of the bulk core-collapse population and a subset which appears to derive largely from massive stars at lower metallicity, although we note that agreement on this matter is not complete (e.g. Podsiadlowski, Joss & Hsu 1992; Eldridge, Izzard & Tout 2008; Smartt 2009; Drout et al. 2011). By exploiting both LGRB and CCSN host samples we can ascertain if there is a strong metallicity dependence in SLSN production, and if this is more or less extreme than that observed in GRB hosts.","Citation Text":["Kochanek 2014"],"Citation Start End":[[584,597]]} {"Identifier":"2016MNRAS.458...84AModjaz_et_al._2008_Instance_1","Paragraph":"While the properties of the SLSN hosts themselves are of interest, they are most diagnostic when compared to other classes of extragalactic transient whose progenitors are better understood. To this end, we employ a comparison sample of LGRB and CCSN3 host galaxies. In principle, CCSNe should trace all core-collapse events, although the mass function means they will be dominated by stars at the lower mass end (∼8 M⊙ to ∼25 M⊙). There also remains a possibility that some very massive stars can undergo core collapse without yielding a LSNe (e.g. Smartt 2009; Ugliano et al. 2012; Kochanek 2014) such that CCSNe samples might only provide a census of lower mass core collapsing stars (e.g. 8 M* 20 M⊙). Indeed, constraints from explosion parameters have shown the majority of CCSNe to be consistent with lower mass progenitors, as opposed to more massive Wolf–Rayet stars (Cano 2013; Lyman et al. 2016) GRBs likely represent a population with rather larger initial masses (Larsson et al. 2007; Raskin et al. 2008). LGRBs are now known to be associated with the core collapse of massive stars, and broad line SN Ic are near ubiquitously associated with low-z events (where such signatures can be seen; Hjorth et al. 2012). When compared to the hosts of CCSNe they are generally smaller and of lower luminosity, consistent with an origin in galaxies of lower metallicity (Fruchter et al. 2006; Svensson et al. 2010). In relatively local examples, where spatially resolved gas phase metallicities can be obtained, these indeed appear to be lower for GRBs than for CCSNe, even in cases where the luminosity of the galaxy is relatively high (i.e. the GRB host galaxies lie off the mass–metallicity relation; Modjaz et al. 2008; Graham & Fruchter 2013). Hence, comparing the hosts of SLSNe to these events allows us to test the large-scale environments of SLSNe against those of the bulk core-collapse population and a subset which appears to derive largely from massive stars at lower metallicity, although we note that agreement on this matter is not complete (e.g. Podsiadlowski, Joss & Hsu 1992; Eldridge, Izzard & Tout 2008; Smartt 2009; Drout et al. 2011). By exploiting both LGRB and CCSN host samples we can ascertain if there is a strong metallicity dependence in SLSN production, and if this is more or less extreme than that observed in GRB hosts.","Citation Text":["Modjaz et al. 2008"],"Citation Start End":[[1708,1726]]} {"Identifier":"2017ApJ...849...63R__Davis_2005_Instance_1","Paragraph":"The distribution of optical depth values at 10 au and 1.3 mm (Figure 7, top) has its maximum at \n\n\n\n\nlog\n\n\nτ\n\n\n1.3\n\nmm\n,\n10\n\nau\n\n\n=\n−\n0.25\n\n\n (corresponding to \n\n\n\n\n\n\nτ\n\n\n1.3\n\nmm\n,\n10\n\nau\n\n\n∼\n0.5\n\n\n), and a secondary peak at \n\n\n\n\nlog\n\n\nτ\n\n\n1.3\n\nmm\n,\n10\n\nau\n\n\n=\n−\n1\n\n\n. We note that the shape of this distribution is determined mostly by Taurus, given the lack of sufficient long-wavelength data for most objects in Chamaeleon I and Ophiuchus, and the distributions in these regions appear to be broader than the one in Taurus (again, this interpretation is limited by the small number statistics in these regions). For comparison, reasonable assumptions about the dust opacity and surface density based on observations of the solar system bodies yield \n\n\n\n\n\n\nτ\n\n\n1\n\nmm\n\n\n=\n1\n\n\n at ∼10 au for the Minimum Mass Solar Nebula (Davis 2005), suggesting that several of the modeled protoplanetary disks may have optical depth profiles (and hence possibly surface densities) similar to that of the parental disk of the solar system. In the case of β, values smaller than the one measured for the ISM (∼1.6–2; see Draine 2006 and references therein) imply some degree of grain growth. Almost the entirety of the Taurus and Ophiuchus distributions (and part of Chamaeleon I) are constrained within that value, in correspondence with the observational result discussed in Section 3.3. As with \n\n\n\n\n\n\nα\n\n\nmm\n\n\n\n\n, Chamaeleon I shows a different behavior (an excess of high β values) that will be discussed further on. We note that the distributions of β should be considered with caution, not only due to the aforementioned caveats, but also because degenerate cases have been removed from the analysis. Because these occur when \n\n\n\n\nα\n=\n2\n\n\n, this procedure inevitably discards objects with \n\n\n\n\nβ\n∼\n0\n\n\n. There is a tentative bimodality in both distributions, especially in the case of β, with a tentative secondary peak occurring at ∼1.4–1.5. Given the limited size of the modeled sample and simplicity of the models used, we do not investigate this issue in detail here. However, we speculate that, if real, it may hint at a quick transition from micron-sized grains (large β values) to mm\/cm-sized dust (smaller β).","Citation Text":["Davis 2005"],"Citation Start End":[[823,833]]} {"Identifier":"2022AandA...664A..63X__Cresci_et_al._2009_Instance_1","Paragraph":"Our SBs and MSs are located in a dense environment. To better understand the environmental effect on gas turbulence, we compare the four cluster members with field galaxies from the literature. The data included in Figs. 5 and 6 contain molecular and ionized gas observations. The ionized gas observations of the star-forming galaxies, sorted by redshifts from the lowest to the highest, are from surveys GHASP (log M*[M⊙]=9.4–11.0; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.6; Epinat et al. 2010), DYNAMO (log M*[M⊙]=9.0–11.8; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.3; Green et al. 2014), MUSE and KMOS (log M*[M⊙]=8.0-11.1; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=9.4, 9.8 at z ∼ 0.7, 1.3; Swinbank et al. 2017), KROSS (log M*[M⊙] = 8.7–11.0; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=9.9; Johnson et al. 2018), KMOS3D (log M*[M⊙]=9.0–11.7; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.5, 10.6, 10.7 at z ∼ 0.9, 1.5, 2.3; Wisnioski et al. 2015; Übler et al. 2019), MASSIV (log M*[M⊙]=9.4–11.0; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.2; Epinat et al. 2012), SIGMA (log M*[M⊙]=9.2–11.8; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.0; Simons et al. 2016), SINS (log M*[M⊙]=9.8–11.5; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.8; Förster Schreiber et al. 2009; Cresci et al. 2009), LAW09 (log M*[M⊙]=9.0–10.9; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.3; Law et al. 2009), AMAZE (log M*[M⊙]=9.2–10.6; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.0; Gnerucci et al. 2011), and KDS (log M*[M⊙]=9.0–10.5; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=9.8; Turner et al. 2017). The molecular gas observations of the star-forming galaxies, sorted by redshifts, are from the HERACLES survey (log M*[M⊙]=7.1–10.9; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=10.5; Leroy et al. 2008, 2009) and the PHIBSS survey (log M*[M⊙]=10.6-11.2; log\n\n\n\nM\n\n\n\n∗\n\n\navg\n\n\n$ M_{\\mathrm{*}}^{\\mathrm{avg}} $\n\n\n[M⊙]=11.0; Tacconi et al. 2013). We note that although the velocity dispersion measured from the molecular gas is ∼10−15 km s−1 lower than from the ionized gas (with extra contributions from thermal broadening and expansion of the HII regions) in the local Universe, this difference becomes smaller with increasing redshift (Übler et al. 2019). Some field SBs with individual CO observations (Calistro Rivera et al. 2018; Barro et al. 2017; Swinbank et al. 2011; Tadaki et al. 2017, 2019) are indicated with blue triangles in Figs. 5 and 6. When possible, we also identified the field starbursts (orange symbols in Figs. 5 and 6) within the above star-forming samples, requiring their SFR to be at least 0.5 dex higher than the MS. In general, the gas in these field starbursts is slightly more turbulent than in main-sequence galaxies, showing a higher σ0, especially at 2   z   4. A similar trend of increasing σ0 as galaxies move above the MS at a fixed stellar mass is shown for star-forming galaxies at z = 0−3 (e.g., Perna et al. 2022; Wisnioski et al. 2015), suggesting that mergers or interactions would increase gas σ0 as they enhance star formation.","Citation Text":["Cresci et al. 2009"],"Citation Start End":[[1447,1465]]} {"Identifier":"2021ApJ...923L...3N__Hama_et_al._2020_Instance_1","Paragraph":"Analytical expressions for the IP and OP spectra obtained by IR–MAIRS are theorized by Itoh et al. (2009) and Shioya et al. (2019). In short, Shioya et al. showed both experimentally and theoretically that the IP spectrum (A\nIP) quantitatively corresponds to the normal-incidence transmission spectrum, \n\n\n\nAthinθ=0\n\n (see the Appendix for details; Shioya et al. 2019).\n5\n\n\n\nAIP=Athinθ=0=8πdaλln102n2k2xy.\n\n\nA\nOP is expressed similarly to A\nIP, while the TO energy-loss function is replaced with a longitudinal optic (LO) energy-loss function: i.e., (2n\n2\nk\n2z\n)\/(\n\n\n\nn22\n\n + k\n2z\n\n2)2 (Shioya et al. 2019; Hama et al. 2020).\n6\n\n\n\nAOP=8πdaHλln10(2n2k2z)n22+k2z22,\n\nwhere H is a substrate-specific correction factor (0.33 for Si) that accounts for the intensity ratio of the electric fields at the optical interface along the surface-parallel and surface-perpendicular directions (Shioya et al. 2019). Because amorphous H2O vapor-deposited at 80–100 K has values of k\n2 that are approximately 2 orders of magnitude smaller than n\n2 (k\n2 ≪n\n2) at 3750–3650 cm−1 in the bulk (Mastrapa et al. 2009), Equation (6) simplifies to\n7\n\n\n\nAOP≈8πdaHλln10(2n2k2z)n24.\n\nFrom Equations (5) and (7), k\n2xy\n and k\n2z\n are derived as\n8\n\n\n\nk2xy=AIPλln1016πdan2\n\n\n\n9\n\n\n\nk2z=n24HAOPλln1016πdan2.\n\nTherefore, optically isotropic k\n2 and σ can be obtained from A\nIP and A\nOP even for a thin sample (Shioya et al. 2020):\n10\n\n\n\nk2=2k2xy+k2z3=2AIP+n24HAOP3λln1016πdan2\n\n\n\n11\n\n\n\nσ=4πdk2λN=4πdλN2AIP+n24HAOP3λln1016πdan2=2AIP+n24HAOP3ln104an2N.\n\nThe band strength β (cm molecule−1) can be also obtained by integrating \n\n\n\nσ(ν˜)\n\n at \n\n\n\nν˜=\n\n 3710–3680 cm−1.\n12\n\n\n\nβ=∫σν˜dν˜=23∫AIPν˜dν˜+n24H3∫AOPν˜dν˜ln104an2N,\n\nwhere \n\n\n\nAIPν˜\n\n and \n\n\n\nAOPν˜\n\n is the IP and OP absorbance at a given wavenumber (\n\n\n\nν˜\n\n), respectively. This study uses n\n1 = 1 for vacuum, n\n2 = 1.26 for amorphous water at 90 K (Kofman et al. 2019), and n\n3=3.41 for Si (Tasumi 2014; Shioya et al. 2019). Hence, a = 0.290 and \n\n\n\nn24\n\n\nH = 0.832. Seven independent measurements for amorphous water formed after 32 minutes of exposure at 90 K gave A\nIP = 0 [\n\n\n\n∫AIPν˜dν˜=0\n\n (cm−1)] and \n\n\n\nn24HAOP\n\n = 6.2 ± 0.4 × 10−5 at 3696 cm−1 [\n\n\n\nn24H∫AOPν˜dν˜\n\n = 8.4 ± 0.4 × 10−4 (cm−1)], considering amorphous water formed on both sides of the Si substrate. Therefore, σ is derived as 1.0 ± 0.2 × 10−18 cm2 at 3696 cm−1 from Equation (11) by adopting N = 3.3 ± 0.6 × 1013 molecules cm−2. β is also derived as 1.4 ± 0.3 × 10−17 cm molecule−1 at \n\n\n\nν̃\n\n = 3710–3680 cm−1 from Equation (12).","Citation Text":["Hama et al. 2020"],"Citation Start End":[[607,623]]} {"Identifier":"2022MNRAS.516.4156D__Sarkar_et_al._2012_Instance_1","Paragraph":"Radio interferometric observations of the redshifted 21-cm signal directly measures the complex visibilities that are the Fourier components of the intensity distribution on the sky. The radio telescope typically has a finite beam that allows us to use the ‘flat-sky’ approximation. Ideally, the fields κ and δT are expanded in the basis of spherical harmonics. For convenience, we use a simplified expression for the angular power spectrum by considering the flat sky approximation whereby we can use the Fourier basis. Using this simplifying assumption, we may approximately write the cross-correlation angular power spectrum as (Dash & Guha Sarkar 2021)\n$$\\begin{eqnarray}\r\nC^{ T \\kappa }_\\ell &=& \\frac{1 }{\\pi (\\chi _2- \\chi _1)} \\sum _{\\chi _1}^{\\chi _2} \\frac{\\Delta \\chi }{\\chi ^2} ~ \\mathcal {A}_T (\\chi) \\mathcal {A}_\\kappa (\\chi) D_{+}^2 (\\chi) \\int _0^{\\infty } \\mathrm{ d}k_{\\parallel }\\\\\r\n&&\\times \\,\\left[ 1 + \\beta _T(\\chi) \\frac{k_{\\parallel }^2}{k^2} \\right] P (k),\r\n\\end{eqnarray}$$where $k = \\sqrt{k_{\\parallel }^2 + \\left(\\frac{\\ell }{\\chi } \\right)^2 }$, D+ is the growing mode of density fluctuations, and βT = f\/bT is the redshift distortion factor – the ratio of the logarithmic growth rate f and the bias function and bT(k, z). The redshift-dependent function $\\mathcal {A}_{T}$ is given by (Bharadwaj & Ali 2005; Datta, Choudhury & Bharadwaj 2007; Guha Sarkar et al. 2012)\n(6)$$\\begin{eqnarray}\r\n\\mathcal {A}_{T} = 4.0 \\, {\\rm {mK}} \\, b_{T} \\, {\\bar{x}_{\\rm H\\,{\\small I}}}(1 + z)^2\\left(\\frac{\\Omega _{b0} h^2}{0.02} \\right) \\left(\\frac{0.7}{h} \\right) \\left(\\frac{H_0}{H(z)} \\right) .\r\n\\end{eqnarray}$$The quantity bT(k, z) is the bias function defined as ratio of H i-21 cm power spectrum to dark matter power spectrum $b_T^2 = P_{\\mathrm{ H}\\,{\\small I}}(z)\/P(z)$. In the post-reionization epoch z 6, the neutral hydrogen fraction remains with a value ${\\bar{x}_{\\rm H\\,{\\small I}}} = 2.45 \\times 10^{-2}$ (adopted from Noterdaeme et al. 2009; Zafar et al. 2013). The clustering of the post-reionization H i is quantified using bT. On sub-Jean’s length, the bias is scale dependent (Fang et al. 1993). However, on large-scale the bias is known to be scale independent. The scale above which the bias is linear, is however sensitive to the redshift. Post-reionization H i bias is studied extensively using N-body simulations (Bagla et al. 2010; Guha Sarkar et al. 2012; Sarkar et al. 2016; Carucci, Villaescusa-Navarro & Viel 2017). These simulations demonstrate that the large-scale linear bias increases with redshift for 1 z 4 (Marín et al. 2010). We have adopted the fitting formula for the bias bT(k, z) as a function of both redshift z and scale k (Guha Sarkar et al. 2012; Sarkar et al. 2016) of the post-reionization signal as\n(7)$$\\begin{eqnarray}\r\nb_{T}(k,z) = \\sum _{m=0}^{4} \\sum _{n=0}^{2} c(m,n) k^{m}z^{n} .\r\n\\end{eqnarray}$$The coefficients c(m, n) in the fit function are adopted from Sarkar et al. (2016).","Citation Text":["Guha Sarkar et al. 2012"],"Citation Start End":[[1391,1414]]} {"Identifier":"2022MNRAS.516.4156D__Sarkar_et_al._2012_Instance_2","Paragraph":"Radio interferometric observations of the redshifted 21-cm signal directly measures the complex visibilities that are the Fourier components of the intensity distribution on the sky. The radio telescope typically has a finite beam that allows us to use the ‘flat-sky’ approximation. Ideally, the fields κ and δT are expanded in the basis of spherical harmonics. For convenience, we use a simplified expression for the angular power spectrum by considering the flat sky approximation whereby we can use the Fourier basis. Using this simplifying assumption, we may approximately write the cross-correlation angular power spectrum as (Dash & Guha Sarkar 2021)\n$$\\begin{eqnarray}\r\nC^{ T \\kappa }_\\ell &=& \\frac{1 }{\\pi (\\chi _2- \\chi _1)} \\sum _{\\chi _1}^{\\chi _2} \\frac{\\Delta \\chi }{\\chi ^2} ~ \\mathcal {A}_T (\\chi) \\mathcal {A}_\\kappa (\\chi) D_{+}^2 (\\chi) \\int _0^{\\infty } \\mathrm{ d}k_{\\parallel }\\\\\r\n&&\\times \\,\\left[ 1 + \\beta _T(\\chi) \\frac{k_{\\parallel }^2}{k^2} \\right] P (k),\r\n\\end{eqnarray}$$where $k = \\sqrt{k_{\\parallel }^2 + \\left(\\frac{\\ell }{\\chi } \\right)^2 }$, D+ is the growing mode of density fluctuations, and βT = f\/bT is the redshift distortion factor – the ratio of the logarithmic growth rate f and the bias function and bT(k, z). The redshift-dependent function $\\mathcal {A}_{T}$ is given by (Bharadwaj & Ali 2005; Datta, Choudhury & Bharadwaj 2007; Guha Sarkar et al. 2012)\n(6)$$\\begin{eqnarray}\r\n\\mathcal {A}_{T} = 4.0 \\, {\\rm {mK}} \\, b_{T} \\, {\\bar{x}_{\\rm H\\,{\\small I}}}(1 + z)^2\\left(\\frac{\\Omega _{b0} h^2}{0.02} \\right) \\left(\\frac{0.7}{h} \\right) \\left(\\frac{H_0}{H(z)} \\right) .\r\n\\end{eqnarray}$$The quantity bT(k, z) is the bias function defined as ratio of H i-21 cm power spectrum to dark matter power spectrum $b_T^2 = P_{\\mathrm{ H}\\,{\\small I}}(z)\/P(z)$. In the post-reionization epoch z 6, the neutral hydrogen fraction remains with a value ${\\bar{x}_{\\rm H\\,{\\small I}}} = 2.45 \\times 10^{-2}$ (adopted from Noterdaeme et al. 2009; Zafar et al. 2013). The clustering of the post-reionization H i is quantified using bT. On sub-Jean’s length, the bias is scale dependent (Fang et al. 1993). However, on large-scale the bias is known to be scale independent. The scale above which the bias is linear, is however sensitive to the redshift. Post-reionization H i bias is studied extensively using N-body simulations (Bagla et al. 2010; Guha Sarkar et al. 2012; Sarkar et al. 2016; Carucci, Villaescusa-Navarro & Viel 2017). These simulations demonstrate that the large-scale linear bias increases with redshift for 1 z 4 (Marín et al. 2010). We have adopted the fitting formula for the bias bT(k, z) as a function of both redshift z and scale k (Guha Sarkar et al. 2012; Sarkar et al. 2016) of the post-reionization signal as\n(7)$$\\begin{eqnarray}\r\nb_{T}(k,z) = \\sum _{m=0}^{4} \\sum _{n=0}^{2} c(m,n) k^{m}z^{n} .\r\n\\end{eqnarray}$$The coefficients c(m, n) in the fit function are adopted from Sarkar et al. (2016).","Citation Text":["Guha Sarkar et al. 2012"],"Citation Start End":[[2393,2416]]} {"Identifier":"2022MNRAS.516.4156D__Sarkar_et_al._2012_Instance_3","Paragraph":"Radio interferometric observations of the redshifted 21-cm signal directly measures the complex visibilities that are the Fourier components of the intensity distribution on the sky. The radio telescope typically has a finite beam that allows us to use the ‘flat-sky’ approximation. Ideally, the fields κ and δT are expanded in the basis of spherical harmonics. For convenience, we use a simplified expression for the angular power spectrum by considering the flat sky approximation whereby we can use the Fourier basis. Using this simplifying assumption, we may approximately write the cross-correlation angular power spectrum as (Dash & Guha Sarkar 2021)\n$$\\begin{eqnarray}\r\nC^{ T \\kappa }_\\ell &=& \\frac{1 }{\\pi (\\chi _2- \\chi _1)} \\sum _{\\chi _1}^{\\chi _2} \\frac{\\Delta \\chi }{\\chi ^2} ~ \\mathcal {A}_T (\\chi) \\mathcal {A}_\\kappa (\\chi) D_{+}^2 (\\chi) \\int _0^{\\infty } \\mathrm{ d}k_{\\parallel }\\\\\r\n&&\\times \\,\\left[ 1 + \\beta _T(\\chi) \\frac{k_{\\parallel }^2}{k^2} \\right] P (k),\r\n\\end{eqnarray}$$where $k = \\sqrt{k_{\\parallel }^2 + \\left(\\frac{\\ell }{\\chi } \\right)^2 }$, D+ is the growing mode of density fluctuations, and βT = f\/bT is the redshift distortion factor – the ratio of the logarithmic growth rate f and the bias function and bT(k, z). The redshift-dependent function $\\mathcal {A}_{T}$ is given by (Bharadwaj & Ali 2005; Datta, Choudhury & Bharadwaj 2007; Guha Sarkar et al. 2012)\n(6)$$\\begin{eqnarray}\r\n\\mathcal {A}_{T} = 4.0 \\, {\\rm {mK}} \\, b_{T} \\, {\\bar{x}_{\\rm H\\,{\\small I}}}(1 + z)^2\\left(\\frac{\\Omega _{b0} h^2}{0.02} \\right) \\left(\\frac{0.7}{h} \\right) \\left(\\frac{H_0}{H(z)} \\right) .\r\n\\end{eqnarray}$$The quantity bT(k, z) is the bias function defined as ratio of H i-21 cm power spectrum to dark matter power spectrum $b_T^2 = P_{\\mathrm{ H}\\,{\\small I}}(z)\/P(z)$. In the post-reionization epoch z 6, the neutral hydrogen fraction remains with a value ${\\bar{x}_{\\rm H\\,{\\small I}}} = 2.45 \\times 10^{-2}$ (adopted from Noterdaeme et al. 2009; Zafar et al. 2013). The clustering of the post-reionization H i is quantified using bT. On sub-Jean’s length, the bias is scale dependent (Fang et al. 1993). However, on large-scale the bias is known to be scale independent. The scale above which the bias is linear, is however sensitive to the redshift. Post-reionization H i bias is studied extensively using N-body simulations (Bagla et al. 2010; Guha Sarkar et al. 2012; Sarkar et al. 2016; Carucci, Villaescusa-Navarro & Viel 2017). These simulations demonstrate that the large-scale linear bias increases with redshift for 1 z 4 (Marín et al. 2010). We have adopted the fitting formula for the bias bT(k, z) as a function of both redshift z and scale k (Guha Sarkar et al. 2012; Sarkar et al. 2016) of the post-reionization signal as\n(7)$$\\begin{eqnarray}\r\nb_{T}(k,z) = \\sum _{m=0}^{4} \\sum _{n=0}^{2} c(m,n) k^{m}z^{n} .\r\n\\end{eqnarray}$$The coefficients c(m, n) in the fit function are adopted from Sarkar et al. (2016).","Citation Text":["Guha Sarkar et al. 2012"],"Citation Start End":[[2705,2728]]} {"Identifier":"2016AandA...585A.125B__Voevodkin_et_al._(2010)_Instance_1","Paragraph":"To investigate this further, we performed an additional test where we froze the slopes for both the fossils and groups to 3.0 and only fit the normalisation for both samples. The value of 3.0 for the slope was chosen as generally most groups and clusters can be described well by this particular slope, after factoring in selection effects. The fossils now have a normalisation of 0.38 ± 0.11 and the groups sample have a normalisation of 0.22 ± 0.13. We now proceeded to remove the influence of selection effects on the normalisation of the scaling relation for both samples by generating mock samples of objects as in Bharadwaj et al. (2015) by varying the input normalisations. For each mock sample, the slope was always fixed to 3 and the intrinsic scatter was fixed to the observed values. Flux and luminosity cuts were applied to both the 400d sample and the groups sample to match the true sample of objects. For the 400d fossil sample, the selection criteria were taken from Voevodkin et al. (2010), and can be described as follows: a lower flux cut of 1.4 × 10-13 erg \/ s \/ cm2, an upper redshift cut of 0.2, and a lower luminosity cut of 1043 erg\/s. Here, fluxes and luminosities are in the ROSAT (0.5–2.0 keV) band. After performing the bias corrections, the fossils scaling relation has a normalisation of 0.30 ± 0.10 vs. 0.0078 ± 0.13 for the groups, indicating that the large normalisations seem to persist even after accounting for selection effects. Despite a nearly 2.3σ higher normalisation for fossils with respect to non-fossils, we still only treat this finding as an indication because on top of the statistical uncertainties in both quantities (which is large currently for the 400d fossils), there could also be an additional systematic uncertainty introduced due to differences in the luminosity determination in the different parent catalogues. Secondly, the archival nature of this subsample of 400d objects is biased towards systems lacking a SCC (Table 2) and, assuming that the remaining systems are SCC, then adding these objects could potentially increase the normalisation for the scaling relation, and the difference between the fossils and the groups sample would be higher than what we demonstrate here. We plan to explore this in greater detail in a future study of fossils scaling relations. ","Citation Text":["Voevodkin et al. (2010)"],"Citation Start End":[[983,1006]]} {"Identifier":"2017MNRAS.464.3679K__Webb_et_al._1999_Instance_1","Paragraph":"In this work, we focus on constraining the variability of the fine-structure constant, α ≡ e2\/ℏc, which represents the coupling strength of the electromagnetic force. In the last 15 years, there have been many attempts to measure this constant in absorption systems along the lines of sight to distant quasars. The approach called the ‘Many Multiplet’ (MM) method, pioneered by Dzuba, Flambaum & Webb (1999) and Webb et al. (1999), compares the relative velocity spacing between different metal ion transitions and relates it to possible variation in α. For example, considering just a single transition, variation in α is related to the velocity shift Δvi of a transition\n\n(1)\n\r\n\\begin{equation}\r\n\\Delta \\alpha \/\\alpha \\equiv \\frac{\\alpha _{\\rm obs}-\\alpha _{\\rm lab}}{\\alpha _{\\rm lab}}\\approx \\frac{-\\Delta v_i}{2c}\\frac{\\omega _i}{q_i},\r\n\\end{equation}\r\n\nwhere c is the speed of light, qi is sensitivity of the transition to α-variation, calculated from many body-relativistic corrections to the energy levels of ions and ωi is its wavenumber measured in the laboratory. There have been two MM method studies of large absorber samples: the Keck High Resolution Echelle Spectrometer (HIRES\/Keck) sample of 143 absorption systems (Webb et al. 1999, 2001; Murphy et al. 2001a, 2004; Murphy, Webb & Flambaum 2003b) and the Ultraviolet and Visual Echelle Spectrograph on the Very Large Telescope (UVES\/VLT) sample of 154 absorption systems (Webb et al. 2011; King et al. 2012). These studies reported weighted mean values of Δα\/α = −5.7 ± 1.1 parts per million (ppm) and 2.29 ± 0.95 ppm, respectively. Webb et al. (2011) and King et al. (2012) also combined both samples and found a 4.1σ statistical preference for a dipole-like variation in α across the sky. Contrary to these studies, several other attempts to measure α from individual absorbers (Quast, Reimers & Levshakov 2004; Levshakov et al. 2005, 2006, 2007; Chand et al. 2006) or smaller samples of absorption systems (Chand et al. 2004; Srianand et al. 2004) reported Δα\/α consistent with zero. However, these analyses contained shortcomings that produced biased values and\/or considerably underestimated error bars (Murphy, Webb & Flambaum 2007a, 2008b; cf. Srianand et al., 2007). For example, a reanalysis, including remodelling of the Chand et al. (2004) spectra by Wilczynska et al. (2015), yielded a weighted mean of Δα\/α = 2.2 ± 2.3 ppm which, given the distribution of the 18 quasars across the sky, was not inconsistent with the evidence for dipole-like α-variation.","Citation Text":["Webb et al. (1999)"],"Citation Start End":[[412,430]]} {"Identifier":"2017MNRAS.464.3679K__Webb_et_al._1999_Instance_2","Paragraph":"In this work, we focus on constraining the variability of the fine-structure constant, α ≡ e2\/ℏc, which represents the coupling strength of the electromagnetic force. In the last 15 years, there have been many attempts to measure this constant in absorption systems along the lines of sight to distant quasars. The approach called the ‘Many Multiplet’ (MM) method, pioneered by Dzuba, Flambaum & Webb (1999) and Webb et al. (1999), compares the relative velocity spacing between different metal ion transitions and relates it to possible variation in α. For example, considering just a single transition, variation in α is related to the velocity shift Δvi of a transition\n\n(1)\n\r\n\\begin{equation}\r\n\\Delta \\alpha \/\\alpha \\equiv \\frac{\\alpha _{\\rm obs}-\\alpha _{\\rm lab}}{\\alpha _{\\rm lab}}\\approx \\frac{-\\Delta v_i}{2c}\\frac{\\omega _i}{q_i},\r\n\\end{equation}\r\n\nwhere c is the speed of light, qi is sensitivity of the transition to α-variation, calculated from many body-relativistic corrections to the energy levels of ions and ωi is its wavenumber measured in the laboratory. There have been two MM method studies of large absorber samples: the Keck High Resolution Echelle Spectrometer (HIRES\/Keck) sample of 143 absorption systems (Webb et al. 1999, 2001; Murphy et al. 2001a, 2004; Murphy, Webb & Flambaum 2003b) and the Ultraviolet and Visual Echelle Spectrograph on the Very Large Telescope (UVES\/VLT) sample of 154 absorption systems (Webb et al. 2011; King et al. 2012). These studies reported weighted mean values of Δα\/α = −5.7 ± 1.1 parts per million (ppm) and 2.29 ± 0.95 ppm, respectively. Webb et al. (2011) and King et al. (2012) also combined both samples and found a 4.1σ statistical preference for a dipole-like variation in α across the sky. Contrary to these studies, several other attempts to measure α from individual absorbers (Quast, Reimers & Levshakov 2004; Levshakov et al. 2005, 2006, 2007; Chand et al. 2006) or smaller samples of absorption systems (Chand et al. 2004; Srianand et al. 2004) reported Δα\/α consistent with zero. However, these analyses contained shortcomings that produced biased values and\/or considerably underestimated error bars (Murphy, Webb & Flambaum 2007a, 2008b; cf. Srianand et al., 2007). For example, a reanalysis, including remodelling of the Chand et al. (2004) spectra by Wilczynska et al. (2015), yielded a weighted mean of Δα\/α = 2.2 ± 2.3 ppm which, given the distribution of the 18 quasars across the sky, was not inconsistent with the evidence for dipole-like α-variation.","Citation Text":["Webb et al. 1999"],"Citation Start End":[[1233,1249]]} {"Identifier":"2017ApJ...845..170B__Emsellem_et_al._2004_Instance_1","Paragraph":"Even when imaged into 40 km s−1 channels, CO(2−1) absorption is apparent in NGC 4374 and IC 4296 against their strong nuclear continuum sources. While extragalactic CO absorption is not frequently observed due to low equivalent widths, ALMA’s high angular resolution and sensitivity allow its detection against some nearby active nuclei (e.g., Davis et al. 2014; Rangwala et al. 2015). To better characterize the central absorption features, we also imaged their visibility data (without continuum subtraction) into cubes with 1.28 km s−1 channels. The primary absorption in IC 4296 is consistent with the galaxy’s assumed systemic velocity (Table 1), although there may be a small secondary absorption feature ∼15 km s−1 redward of \n\n\n\n\n\n. The CO(1−2) transition seen in the nucleus of NGC 4374, however, is redshifted by ∼100 km s−1 from the \n\n\n\n\n\n value derived using stellar kinematics (Emsellem et al. 2004) and by ∼50 km s−1 with respect to the best-fitting \n\n\n\n\n\n from ionized gas dynamical modeling (e.g., Walsh et al. 2010). The absorption lines in these two galaxies have narrow widths (≲7 km s−1 FWHM) that are only slightly smaller than the minimum line widths in our CO-bright subsample. Maximum absorption depths are (−3.26 ± 0.74) and (−5.25 ± 0.35) K with integrated absorption intensities \n\n\n\n\n\n of (19.4 ± 2.5) and (44.3 ± 1.4) K km s−1 for NGC 4374 and IC 4296, respectively. From these \n\n\n\n\n\n measurements, we estimate corresponding H2 column densities \n\n\n\n\n\n of \n\n\n\n\n\n and \n\n\n\n\n\n cm−2 after assuming an absorption depth ratio CO(1−2)\/CO(0−1) ≈ 0.6 (based on 13CO absorption line ratios; e.g., see Eckart et al. 1990) and a CO-to-H2 conversion factor \n\n\n\n\n\n corresponding to \n\n\n\n\n\n M pc−2 (K km s−1)−1 (see Section 3.1.2; Sandstrom et al. 2013). These \n\n\n\n\n\n estimates are much more uncertain than indicated by the formal associated uncertainties, since the \n\n\n\n\n\n and CO(1−2)\/CO(1−0) values carry large systematic uncertainties, and faint nuclear CO emission may somewhat dilute these equivalent widths.","Citation Text":["Emsellem et al. 2004"],"Citation Start End":[[891,911]]} {"Identifier":"2016ApJ...821...67S__Ruiter_et_al._2013_Instance_1","Paragraph":"In order to examine how our qcr(M1) would affect the brightness distribution of the violent merger scenario, we adopt the same assumptions as in Ruiter et al. (2013) except for qcr(M1). For the primary at the time of merging, we use the same WD mass distribution as Ruiter et al. (2013; see also Ruiter et al. 2011), although it is highly uncertain whether the WD can increase its mass by avoiding the formation of a common envelope during the very rapid accretion from the He star companion. We also assume the same \n\n\n\n\n\n\nm\n\n\nWD\n\n\n–\n\n\nM\n\n\nbol\n\n\n\n\n relation of SNe Ia as Ruiter et al. (2013; see Figure 4 in Ruiter et al. 2013; Sim et al. 2010) and a flat mass ratio distribution of DD systems for simplicity. Using either our critical mass ratio or theirs, we calculated the brightness distribution and compared them with each other (Figure 11). We find that there is no significant difference between them qualitatively. This result implies that the qcr of the violent merger-induced explosion is not so crucial for the brightness distribution of SNe Ia, as mentioned in Ruiter et al. (2013). Our results are closest to the η = 1.5 case among Ruiter et al.'s three cases. In the cases of our qcr and Ruiter et al.'s η = 1.5, the brightness distribution concentrates around −19.0 mag. In Figure 11, we add the observational volume-limited brightness distributions of SNe Ia. One in panel (a) is derived by the Lick Observatory Supernova Search (LOSS; Li et al. 2011), and the other in panel (b) is obtained by ROTSE-IIIb (see Table 1 in Quimby et al. 2012). The fraction of faint events in our models is lower than the observation of LOSS. This discrepancy might decrease if we consider the viewing angle effects (see also the discussion in Ruiter et al. 2013), which might be increasingly important especially for a large value of qcr. On the other hand, the results of ROTSE-IIIb are consistent with ours, except most luminous (≲−19.5 mag) events. It should be noted, however, that there are large uncertainties for the observational brightness distribution (e.g., Quimby et al. 2012) and our models are too simple to be compared with the observational results. More detailed studies are required to reach a definitive conclusion.","Citation Text":["Ruiter et al. (2013)"],"Citation Start End":[[145,165]]} {"Identifier":"2016ApJ...821...67S__Ruiter_et_al._2013_Instance_2","Paragraph":"In order to examine how our qcr(M1) would affect the brightness distribution of the violent merger scenario, we adopt the same assumptions as in Ruiter et al. (2013) except for qcr(M1). For the primary at the time of merging, we use the same WD mass distribution as Ruiter et al. (2013; see also Ruiter et al. 2011), although it is highly uncertain whether the WD can increase its mass by avoiding the formation of a common envelope during the very rapid accretion from the He star companion. We also assume the same \n\n\n\n\n\n\nm\n\n\nWD\n\n\n–\n\n\nM\n\n\nbol\n\n\n\n\n relation of SNe Ia as Ruiter et al. (2013; see Figure 4 in Ruiter et al. 2013; Sim et al. 2010) and a flat mass ratio distribution of DD systems for simplicity. Using either our critical mass ratio or theirs, we calculated the brightness distribution and compared them with each other (Figure 11). We find that there is no significant difference between them qualitatively. This result implies that the qcr of the violent merger-induced explosion is not so crucial for the brightness distribution of SNe Ia, as mentioned in Ruiter et al. (2013). Our results are closest to the η = 1.5 case among Ruiter et al.'s three cases. In the cases of our qcr and Ruiter et al.'s η = 1.5, the brightness distribution concentrates around −19.0 mag. In Figure 11, we add the observational volume-limited brightness distributions of SNe Ia. One in panel (a) is derived by the Lick Observatory Supernova Search (LOSS; Li et al. 2011), and the other in panel (b) is obtained by ROTSE-IIIb (see Table 1 in Quimby et al. 2012). The fraction of faint events in our models is lower than the observation of LOSS. This discrepancy might decrease if we consider the viewing angle effects (see also the discussion in Ruiter et al. 2013), which might be increasingly important especially for a large value of qcr. On the other hand, the results of ROTSE-IIIb are consistent with ours, except most luminous (≲−19.5 mag) events. It should be noted, however, that there are large uncertainties for the observational brightness distribution (e.g., Quimby et al. 2012) and our models are too simple to be compared with the observational results. More detailed studies are required to reach a definitive conclusion.","Citation Text":["Ruiter et al. (2013"],"Citation Start End":[[266,285]]} {"Identifier":"2016ApJ...821...67S__Ruiter_et_al._2013_Instance_4","Paragraph":"In order to examine how our qcr(M1) would affect the brightness distribution of the violent merger scenario, we adopt the same assumptions as in Ruiter et al. (2013) except for qcr(M1). For the primary at the time of merging, we use the same WD mass distribution as Ruiter et al. (2013; see also Ruiter et al. 2011), although it is highly uncertain whether the WD can increase its mass by avoiding the formation of a common envelope during the very rapid accretion from the He star companion. We also assume the same \n\n\n\n\n\n\nm\n\n\nWD\n\n\n–\n\n\nM\n\n\nbol\n\n\n\n\n relation of SNe Ia as Ruiter et al. (2013; see Figure 4 in Ruiter et al. 2013; Sim et al. 2010) and a flat mass ratio distribution of DD systems for simplicity. Using either our critical mass ratio or theirs, we calculated the brightness distribution and compared them with each other (Figure 11). We find that there is no significant difference between them qualitatively. This result implies that the qcr of the violent merger-induced explosion is not so crucial for the brightness distribution of SNe Ia, as mentioned in Ruiter et al. (2013). Our results are closest to the η = 1.5 case among Ruiter et al.'s three cases. In the cases of our qcr and Ruiter et al.'s η = 1.5, the brightness distribution concentrates around −19.0 mag. In Figure 11, we add the observational volume-limited brightness distributions of SNe Ia. One in panel (a) is derived by the Lick Observatory Supernova Search (LOSS; Li et al. 2011), and the other in panel (b) is obtained by ROTSE-IIIb (see Table 1 in Quimby et al. 2012). The fraction of faint events in our models is lower than the observation of LOSS. This discrepancy might decrease if we consider the viewing angle effects (see also the discussion in Ruiter et al. 2013), which might be increasingly important especially for a large value of qcr. On the other hand, the results of ROTSE-IIIb are consistent with ours, except most luminous (≲−19.5 mag) events. It should be noted, however, that there are large uncertainties for the observational brightness distribution (e.g., Quimby et al. 2012) and our models are too simple to be compared with the observational results. More detailed studies are required to reach a definitive conclusion.","Citation Text":["Ruiter et al. 2013"],"Citation Start End":[[609,627]]} {"Identifier":"2016ApJ...821...67S__Ruiter_et_al._2013_Instance_3","Paragraph":"In order to examine how our qcr(M1) would affect the brightness distribution of the violent merger scenario, we adopt the same assumptions as in Ruiter et al. (2013) except for qcr(M1). For the primary at the time of merging, we use the same WD mass distribution as Ruiter et al. (2013; see also Ruiter et al. 2011), although it is highly uncertain whether the WD can increase its mass by avoiding the formation of a common envelope during the very rapid accretion from the He star companion. We also assume the same \n\n\n\n\n\n\nm\n\n\nWD\n\n\n–\n\n\nM\n\n\nbol\n\n\n\n\n relation of SNe Ia as Ruiter et al. (2013; see Figure 4 in Ruiter et al. 2013; Sim et al. 2010) and a flat mass ratio distribution of DD systems for simplicity. Using either our critical mass ratio or theirs, we calculated the brightness distribution and compared them with each other (Figure 11). We find that there is no significant difference between them qualitatively. This result implies that the qcr of the violent merger-induced explosion is not so crucial for the brightness distribution of SNe Ia, as mentioned in Ruiter et al. (2013). Our results are closest to the η = 1.5 case among Ruiter et al.'s three cases. In the cases of our qcr and Ruiter et al.'s η = 1.5, the brightness distribution concentrates around −19.0 mag. In Figure 11, we add the observational volume-limited brightness distributions of SNe Ia. One in panel (a) is derived by the Lick Observatory Supernova Search (LOSS; Li et al. 2011), and the other in panel (b) is obtained by ROTSE-IIIb (see Table 1 in Quimby et al. 2012). The fraction of faint events in our models is lower than the observation of LOSS. This discrepancy might decrease if we consider the viewing angle effects (see also the discussion in Ruiter et al. 2013), which might be increasingly important especially for a large value of qcr. On the other hand, the results of ROTSE-IIIb are consistent with ours, except most luminous (≲−19.5 mag) events. It should be noted, however, that there are large uncertainties for the observational brightness distribution (e.g., Quimby et al. 2012) and our models are too simple to be compared with the observational results. More detailed studies are required to reach a definitive conclusion.","Citation Text":["Ruiter et al. (2013"],"Citation Start End":[[572,591]]} {"Identifier":"2016ApJ...821...67S__Ruiter_et_al._2013_Instance_5","Paragraph":"In order to examine how our qcr(M1) would affect the brightness distribution of the violent merger scenario, we adopt the same assumptions as in Ruiter et al. (2013) except for qcr(M1). For the primary at the time of merging, we use the same WD mass distribution as Ruiter et al. (2013; see also Ruiter et al. 2011), although it is highly uncertain whether the WD can increase its mass by avoiding the formation of a common envelope during the very rapid accretion from the He star companion. We also assume the same \n\n\n\n\n\n\nm\n\n\nWD\n\n\n–\n\n\nM\n\n\nbol\n\n\n\n\n relation of SNe Ia as Ruiter et al. (2013; see Figure 4 in Ruiter et al. 2013; Sim et al. 2010) and a flat mass ratio distribution of DD systems for simplicity. Using either our critical mass ratio or theirs, we calculated the brightness distribution and compared them with each other (Figure 11). We find that there is no significant difference between them qualitatively. This result implies that the qcr of the violent merger-induced explosion is not so crucial for the brightness distribution of SNe Ia, as mentioned in Ruiter et al. (2013). Our results are closest to the η = 1.5 case among Ruiter et al.'s three cases. In the cases of our qcr and Ruiter et al.'s η = 1.5, the brightness distribution concentrates around −19.0 mag. In Figure 11, we add the observational volume-limited brightness distributions of SNe Ia. One in panel (a) is derived by the Lick Observatory Supernova Search (LOSS; Li et al. 2011), and the other in panel (b) is obtained by ROTSE-IIIb (see Table 1 in Quimby et al. 2012). The fraction of faint events in our models is lower than the observation of LOSS. This discrepancy might decrease if we consider the viewing angle effects (see also the discussion in Ruiter et al. 2013), which might be increasingly important especially for a large value of qcr. On the other hand, the results of ROTSE-IIIb are consistent with ours, except most luminous (≲−19.5 mag) events. It should be noted, however, that there are large uncertainties for the observational brightness distribution (e.g., Quimby et al. 2012) and our models are too simple to be compared with the observational results. More detailed studies are required to reach a definitive conclusion.","Citation Text":["Ruiter et al. (2013)"],"Citation Start End":[[1074,1094]]} {"Identifier":"2016ApJ...821...67S__Ruiter_et_al._2013_Instance_6","Paragraph":"In order to examine how our qcr(M1) would affect the brightness distribution of the violent merger scenario, we adopt the same assumptions as in Ruiter et al. (2013) except for qcr(M1). For the primary at the time of merging, we use the same WD mass distribution as Ruiter et al. (2013; see also Ruiter et al. 2011), although it is highly uncertain whether the WD can increase its mass by avoiding the formation of a common envelope during the very rapid accretion from the He star companion. We also assume the same \n\n\n\n\n\n\nm\n\n\nWD\n\n\n–\n\n\nM\n\n\nbol\n\n\n\n\n relation of SNe Ia as Ruiter et al. (2013; see Figure 4 in Ruiter et al. 2013; Sim et al. 2010) and a flat mass ratio distribution of DD systems for simplicity. Using either our critical mass ratio or theirs, we calculated the brightness distribution and compared them with each other (Figure 11). We find that there is no significant difference between them qualitatively. This result implies that the qcr of the violent merger-induced explosion is not so crucial for the brightness distribution of SNe Ia, as mentioned in Ruiter et al. (2013). Our results are closest to the η = 1.5 case among Ruiter et al.'s three cases. In the cases of our qcr and Ruiter et al.'s η = 1.5, the brightness distribution concentrates around −19.0 mag. In Figure 11, we add the observational volume-limited brightness distributions of SNe Ia. One in panel (a) is derived by the Lick Observatory Supernova Search (LOSS; Li et al. 2011), and the other in panel (b) is obtained by ROTSE-IIIb (see Table 1 in Quimby et al. 2012). The fraction of faint events in our models is lower than the observation of LOSS. This discrepancy might decrease if we consider the viewing angle effects (see also the discussion in Ruiter et al. 2013), which might be increasingly important especially for a large value of qcr. On the other hand, the results of ROTSE-IIIb are consistent with ours, except most luminous (≲−19.5 mag) events. It should be noted, however, that there are large uncertainties for the observational brightness distribution (e.g., Quimby et al. 2012) and our models are too simple to be compared with the observational results. More detailed studies are required to reach a definitive conclusion.","Citation Text":["Ruiter et al. 2013"],"Citation Start End":[[1743,1761]]} {"Identifier":"2022ApJ...936...81B__Ye_et_al._2018_Instance_1","Paragraph":"Since its discovery in 1983, Phaethon has remained a well-studied yet poorly understood object, known to exhibit both cometary and asteroidal characteristics, and widely presumed to be the parent to the Earth-crossing Geminid meteor shower (Green & Kowal 1983; Gustafson 1989; Williams & Wu 1993). Significant efforts have been made to study the physical properties of the asteroid such as size (6 km in diameter, Taylor et al. 2019), spectral shape (B type, e.g., Licandro et al. 2007), and albedo (0.11, Green et al. 1985), as well as the Geminids (e.g., Hughes & McBride 1989; Jenniskens 1994; Arlt & Rendtel 2006; Blaauw 2017), their relationship to one another (e.g., Gustafson 1989; de León et al. 2010), and the proposed relationship to asteroids 2005 UD and 1999 YC (e.g., Ohtsuka et al. 2006, 2008; Kareta et al. 2021). Several Earth-based studies of Phaethon have sought to investigate the perihelion activity of the asteroid, attempting—but failing—to detect small fragments (Jewitt et al. 2018; Ye et al. 2018) or nearby dust grains (Jewitt et al. 2019) released during its close (0.14 au) passage by the Sun. Despite this, spacecraft observations of Phaethon’s activity at perihelion obtained by the Sun-Earth Connection Coronal and Heliospheric Investigation (Howard et al. 2008) on NASA’s Solar Terrestrial Relations Observatory (Kaiser et al. 2008) during the asteroid’s perihelion passages in 2009, 2012, 2016, and 2022, have shown that the asteroid is clearly active at perihelion, displaying a short tail and reported to be releasing mass on the order ∼2.5 × 108\na\n1 kg (where a\n1 is the grain radius in millimeters, and noting that the size of dust released at perihelion remains unknown; Jewitt & Li 2010; Jewitt et al. 2013; Hui & Li 2017). This is insufficient by orders of magnitude to support the best estimates for the mass of the Geminids. Shortly before submission of this manuscript, Phaethon was also observed by the Solar and Heliospheric Observatory Large Angle Spectrometric Coronagraph (Brueckner et al. 1995) C2 coronagraph during its 2022 May 15 perihelion passage, constituting the first known detection of Phaethon by this instrument.","Citation Text":["Ye et al. 2018"],"Citation Start End":[[1007,1021]]} {"Identifier":"2022ApJ...936...81BGreen_&_Kowal_1983_Instance_1","Paragraph":"Since its discovery in 1983, Phaethon has remained a well-studied yet poorly understood object, known to exhibit both cometary and asteroidal characteristics, and widely presumed to be the parent to the Earth-crossing Geminid meteor shower (Green & Kowal 1983; Gustafson 1989; Williams & Wu 1993). Significant efforts have been made to study the physical properties of the asteroid such as size (6 km in diameter, Taylor et al. 2019), spectral shape (B type, e.g., Licandro et al. 2007), and albedo (0.11, Green et al. 1985), as well as the Geminids (e.g., Hughes & McBride 1989; Jenniskens 1994; Arlt & Rendtel 2006; Blaauw 2017), their relationship to one another (e.g., Gustafson 1989; de León et al. 2010), and the proposed relationship to asteroids 2005 UD and 1999 YC (e.g., Ohtsuka et al. 2006, 2008; Kareta et al. 2021). Several Earth-based studies of Phaethon have sought to investigate the perihelion activity of the asteroid, attempting—but failing—to detect small fragments (Jewitt et al. 2018; Ye et al. 2018) or nearby dust grains (Jewitt et al. 2019) released during its close (0.14 au) passage by the Sun. Despite this, spacecraft observations of Phaethon’s activity at perihelion obtained by the Sun-Earth Connection Coronal and Heliospheric Investigation (Howard et al. 2008) on NASA’s Solar Terrestrial Relations Observatory (Kaiser et al. 2008) during the asteroid’s perihelion passages in 2009, 2012, 2016, and 2022, have shown that the asteroid is clearly active at perihelion, displaying a short tail and reported to be releasing mass on the order ∼2.5 × 108\na\n1 kg (where a\n1 is the grain radius in millimeters, and noting that the size of dust released at perihelion remains unknown; Jewitt & Li 2010; Jewitt et al. 2013; Hui & Li 2017). This is insufficient by orders of magnitude to support the best estimates for the mass of the Geminids. Shortly before submission of this manuscript, Phaethon was also observed by the Solar and Heliospheric Observatory Large Angle Spectrometric Coronagraph (Brueckner et al. 1995) C2 coronagraph during its 2022 May 15 perihelion passage, constituting the first known detection of Phaethon by this instrument.","Citation Text":["Green & Kowal 1983"],"Citation Start End":[[241,259]]} {"Identifier":"2022ApJ...936...81BOhtsuka_et_al._2006_Instance_1","Paragraph":"Since its discovery in 1983, Phaethon has remained a well-studied yet poorly understood object, known to exhibit both cometary and asteroidal characteristics, and widely presumed to be the parent to the Earth-crossing Geminid meteor shower (Green & Kowal 1983; Gustafson 1989; Williams & Wu 1993). Significant efforts have been made to study the physical properties of the asteroid such as size (6 km in diameter, Taylor et al. 2019), spectral shape (B type, e.g., Licandro et al. 2007), and albedo (0.11, Green et al. 1985), as well as the Geminids (e.g., Hughes & McBride 1989; Jenniskens 1994; Arlt & Rendtel 2006; Blaauw 2017), their relationship to one another (e.g., Gustafson 1989; de León et al. 2010), and the proposed relationship to asteroids 2005 UD and 1999 YC (e.g., Ohtsuka et al. 2006, 2008; Kareta et al. 2021). Several Earth-based studies of Phaethon have sought to investigate the perihelion activity of the asteroid, attempting—but failing—to detect small fragments (Jewitt et al. 2018; Ye et al. 2018) or nearby dust grains (Jewitt et al. 2019) released during its close (0.14 au) passage by the Sun. Despite this, spacecraft observations of Phaethon’s activity at perihelion obtained by the Sun-Earth Connection Coronal and Heliospheric Investigation (Howard et al. 2008) on NASA’s Solar Terrestrial Relations Observatory (Kaiser et al. 2008) during the asteroid’s perihelion passages in 2009, 2012, 2016, and 2022, have shown that the asteroid is clearly active at perihelion, displaying a short tail and reported to be releasing mass on the order ∼2.5 × 108\na\n1 kg (where a\n1 is the grain radius in millimeters, and noting that the size of dust released at perihelion remains unknown; Jewitt & Li 2010; Jewitt et al. 2013; Hui & Li 2017). This is insufficient by orders of magnitude to support the best estimates for the mass of the Geminids. Shortly before submission of this manuscript, Phaethon was also observed by the Solar and Heliospheric Observatory Large Angle Spectrometric Coronagraph (Brueckner et al. 1995) C2 coronagraph during its 2022 May 15 perihelion passage, constituting the first known detection of Phaethon by this instrument.","Citation Text":["Ohtsuka et al. 2006"],"Citation Start End":[[781,800]]} {"Identifier":"2022ApJ...937L..34K__McKinney_et_al._2012_Instance_1","Paragraph":"We consider a radio galaxy of SMBH mass M = 109\nM\n9\nM\n⊙ with a mass accretion rate of \n\n\n\nṀ=ṁLEdd\/c2≃1.4×1022M9ṁ−4gcm−2\n\n, where c is the speed of light and L\nEdd is the Eddington luminosity. The gravitational radius of the BH is r\n\ng\n = GM\/c\n2 ≃ 1.5 × 1014\nM\n9 cm. We consider that the accretion flow is in the MAD state, and then the magnetic field strength around the SMBH is estimated to be \n\n\n\nBmad=ṀcΦmad2\/(4π2rg2)≃1.1×103M9−1\/2ṁ−41\/2Φmad,1.7G\n\n (e.g., Yuan & Narayan 2014), where Φmad ≈ 50Φmad,1.7 is the saturated magnetic flux (Tchekhovskoy et al. 2011; Narayan et al. 2012; McKinney et al. 2012; White et al. 2019). The high-resolution GRMHD simulation with a BH spin parameter a = 0.9375 suggests that magnetic reconnection occurs at a distance of r\nrec ∼ 2r\n\ng\n (Ripperda et al. 2022). The value of r\nrec could depend on a or other parameters, but we fix r\nrec = 2r\n\ng\n throughout this paper for simplicity. We estimate the reconnecting magnetic field strength to be (see Appendix A)\n1\n\n\n\nBrec≈2Bmadrrecrg−2≃3.9×102M9−1\/2ṁ−41\/2Φrec,1.2G,\n\nwhere \n\n\n\nΦrec=2Φmad(rrec\/rg)−2\n\n is the effective magnetic flux at the reconnection region. The magnetosphere will be formed around the SMBH. The minimum number density of the magnetosphere that can maintain the electric current for the BZ process is (Goldreich & Julian 1969; Levinson & Cerutti 2018)\n2\n\n\n\nnGJ=BrecΩF2πec≈Brec8πerg≃2.2×10−4M9−3\/2ṁ−41\/2Φrec,1.2cm−3,\n\nwhere Ω\nF\n ≈ ac\/(4r\n\ng\n) is the field line angular velocity (Tchekhovskoy et al. 2010; Nathanail & Contopoulos 2014; Ogihara et al. 2021; Camilloni et al. 2022) and we assume the BH spin parameter as a ∼ 1. For the magnetosphere, which consists of e\n+\ne\n− pair plasma with the density n\nGJ, the magnetization parameter is\n3\n\n\n\nσB,GJ=Brec24πnGJmec2≈6.8×1013M91\/2ṁ−41\/2Φrec,1.2.\n\nThis value should be regarded as an upper limit, because the number density of the magnetosphere can be higher than n\nGJ. Various mechanisms of particle injection into the BH magnetosphere have been proposed (see Appendix B), which can lead to multiplicity of κ\n± ≡ n\/n\nGJ ∼ 1 − 103. This results in the magnetization parameter of σ\n\nB\n ≳ 1010.","Citation Text":["McKinney et al. 2012"],"Citation Start End":[[589,609]]} {"Identifier":"2021MNRAS.503.5473A__Enßlin_&_Kaiser_2000_Instance_1","Paragraph":"It is well known that energetic electrons can boost the CMB photons to higher energy through inverse Compton scattering creating a distortion in the CMB blackbody spectrum. If the energy distribution of the electrons is non-relativistic and thermal, then the distortion has y-distortion shape (Zeldovich & Sunyaev 1969) (see Section 6 for further discussions on corrections to y-distortion). For relativistic electrons, with a Lorentz factor γ, a photon with energy ϵ gets boosted to γ2ϵ. In this case, the spectral distortion shape will be a function of the electron energy distribution. The intensity of the CMB spectrum per frequency is given by,\n(9)$$\\begin{eqnarray*}\r\nI_{\\nu }(x)=2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^3}{({hc})^2}\\frac{x^3}{e^x-1}=I_0I(x),\r\n\\end{eqnarray*}$$where $I(x)=\\frac{x^3}{e^x-1}$, I(x) is the dimensionless intensity, x is the dimensional frequency which is given by $x=\\frac{E_{\\gamma }}{k_{\\rm {B}}T_{\\rm {CMB}}}$, where Eγ is the energy of photon, kB is the Boltzmann constant, TCMB is the CMB temperature, and other symbols have usual meanings. The intensity of distorted CMB spectrum is independent of redshift for a given population of electrons. The CMB distortion in the optically thin limit can be written as (Zeldovich & Sunyaev 1969; Birkinshaw 1999),\n(10)$$\\begin{eqnarray*}\r\n\\Delta I(x)=(j(x)-i(x))\\tau ,\r\n\\end{eqnarray*}$$where j(x) is the spectral intensity of photons at frequency x after being upscattered while i(x) is the intensity of photons at frequency x before upscattering, τ = σT∫nedl where ne is the electron number density and dl is the line-of-sight width of this electron population. i(x) is non-zero over the range of x where the CMB photons are present. Equation (10) can be recast to include a y-parameter as ΔI(x) = yg(x), where $y=\\frac{\\sigma _{\\rm {T}}}{m_{\\rm {e}}\\rm {c}^2}\\int n_{\\rm {e}}k_{\\rm {B}}\\overset{\\sim }{T_{\\rm {e}}}\\mathrm{ d}l$ with $k_{\\rm {B}}\\overset{\\sim }{T_{\\rm {e}}}=\\frac{P_{\\rm {e}}}{n_{\\rm {e}}}$. Here $\\overset{\\sim }{T_{\\rm {e}}}$ refers to a fictitious temperature scale for a non-thermal distribution to make the equations look suggestively similar to thermal SZ (more details can be found in Enßlin & Kaiser 2000). In order to distinguish non-thermal spectral distortion shape from y-type distortion (the well-known thermal $\\rm {SZ}$ effect), we will refer to non-thermal distortion amplitude as yNT, such that,\n(11)$$\\begin{eqnarray*}\r\n\\Delta I_{\\rm {NT}}(x)=y_{\\rm {NT}}g_{\\rm {NT}}(x),\r\n\\end{eqnarray*}$$where gNT(x) is the spectral distortion function resulting from scattering of the CMB in a non-thermal population of clusters. We use the formalism of Enßlin & Kaiser (2000) to compute gNT(x) and we refer the reader to the paper for details. The pressure for a distribution of relativistic electrons is given by,\n(12)$$\\begin{eqnarray*}\r\nP_{\\rm {e}}=n_{\\rm {e}}\\int \\mathrm{ d}p f_{\\rm {e}}(p)\\frac{1}{3}p{v}(p)m_{\\rm {e}}c,\r\n\\end{eqnarray*}$$where fe(p) is the normalized electron spectrum i.e. ∫fe(p)dp = 1 with electron dimension-less momentum $p=\\sqrt{(\\gamma ^2-1)}$, v = βc, where γ is the Lorentz factor and β is the boost factor of energetic electrons. The number of CMB photons which get upscattered from energy x′ to x is given by,\n(13)$$\\begin{eqnarray*}\r\nN(x^{\\prime }-\\gt x)= P(t,p)\\times 2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^2}{({hc})^2}\\frac{x^{\\prime 2}\\mathrm{ d}x^{\\prime }}{e^{x^{\\prime }}-1},\r\n\\end{eqnarray*}$$where P(t, p) is the kernel of the inverse Compton scattering which captures the kinematics of photon scattering with the electrons with electron energy p, $t=\\frac{x}{x^{\\prime }}$. The number of CMB photons within energy x′ and x′ + dx′ is $2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^2}{({hc})^2}\\frac{x^{\\prime 2}dx^{\\prime }}{e^{x^{\\prime }}-1}$ and ∫dtP(t, p) = 1, which conserves the number of photons. The formula for P(t, p) is given by (Enßlin & Kaiser 2000),\n(14)$$\\begin{eqnarray*}\r\nP(t;p)&=&\\frac{-3\\left|(1-t)\\right|}{32p^6t}[1+(10+8p^2+4p^4)t+t^2]+\\frac{3(1+t)}{8p^5}\\nonumber\\\\\r\n&&\\times \\left[\\frac{3+3p^2+p^4}{\\sqrt{1+p^2}}-\\frac{3+2p^2}{2p}(2\\operatorname{arcsinh}{p}-\\left| \\ln {t}\\right|)\\right],\\nonumber\\\\\r\n\\end{eqnarray*}$$The spectral intensity of upscattered photons per frequency, in frequency bin x and x + Δx, is given by,\n(15)$$\\begin{eqnarray*}\r\nj(x)=\\frac{\\int \\int f_{\\rm {e}}(p)\\mathrm{ d}p P(t,p)\\frac{x^{\\prime 2}\\mathrm{ d}x^{\\prime }}{e^{x^{\\prime }}-1}x}{\\Delta x}.\r\n\\end{eqnarray*}$$","Citation Text":["Enßlin & Kaiser 2000"],"Citation Start End":[[2188,2208]]} {"Identifier":"2021MNRAS.503.5473A__Enßlin_&_Kaiser_2000_Instance_2","Paragraph":"It is well known that energetic electrons can boost the CMB photons to higher energy through inverse Compton scattering creating a distortion in the CMB blackbody spectrum. If the energy distribution of the electrons is non-relativistic and thermal, then the distortion has y-distortion shape (Zeldovich & Sunyaev 1969) (see Section 6 for further discussions on corrections to y-distortion). For relativistic electrons, with a Lorentz factor γ, a photon with energy ϵ gets boosted to γ2ϵ. In this case, the spectral distortion shape will be a function of the electron energy distribution. The intensity of the CMB spectrum per frequency is given by,\n(9)$$\\begin{eqnarray*}\r\nI_{\\nu }(x)=2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^3}{({hc})^2}\\frac{x^3}{e^x-1}=I_0I(x),\r\n\\end{eqnarray*}$$where $I(x)=\\frac{x^3}{e^x-1}$, I(x) is the dimensionless intensity, x is the dimensional frequency which is given by $x=\\frac{E_{\\gamma }}{k_{\\rm {B}}T_{\\rm {CMB}}}$, where Eγ is the energy of photon, kB is the Boltzmann constant, TCMB is the CMB temperature, and other symbols have usual meanings. The intensity of distorted CMB spectrum is independent of redshift for a given population of electrons. The CMB distortion in the optically thin limit can be written as (Zeldovich & Sunyaev 1969; Birkinshaw 1999),\n(10)$$\\begin{eqnarray*}\r\n\\Delta I(x)=(j(x)-i(x))\\tau ,\r\n\\end{eqnarray*}$$where j(x) is the spectral intensity of photons at frequency x after being upscattered while i(x) is the intensity of photons at frequency x before upscattering, τ = σT∫nedl where ne is the electron number density and dl is the line-of-sight width of this electron population. i(x) is non-zero over the range of x where the CMB photons are present. Equation (10) can be recast to include a y-parameter as ΔI(x) = yg(x), where $y=\\frac{\\sigma _{\\rm {T}}}{m_{\\rm {e}}\\rm {c}^2}\\int n_{\\rm {e}}k_{\\rm {B}}\\overset{\\sim }{T_{\\rm {e}}}\\mathrm{ d}l$ with $k_{\\rm {B}}\\overset{\\sim }{T_{\\rm {e}}}=\\frac{P_{\\rm {e}}}{n_{\\rm {e}}}$. Here $\\overset{\\sim }{T_{\\rm {e}}}$ refers to a fictitious temperature scale for a non-thermal distribution to make the equations look suggestively similar to thermal SZ (more details can be found in Enßlin & Kaiser 2000). In order to distinguish non-thermal spectral distortion shape from y-type distortion (the well-known thermal $\\rm {SZ}$ effect), we will refer to non-thermal distortion amplitude as yNT, such that,\n(11)$$\\begin{eqnarray*}\r\n\\Delta I_{\\rm {NT}}(x)=y_{\\rm {NT}}g_{\\rm {NT}}(x),\r\n\\end{eqnarray*}$$where gNT(x) is the spectral distortion function resulting from scattering of the CMB in a non-thermal population of clusters. We use the formalism of Enßlin & Kaiser (2000) to compute gNT(x) and we refer the reader to the paper for details. The pressure for a distribution of relativistic electrons is given by,\n(12)$$\\begin{eqnarray*}\r\nP_{\\rm {e}}=n_{\\rm {e}}\\int \\mathrm{ d}p f_{\\rm {e}}(p)\\frac{1}{3}p{v}(p)m_{\\rm {e}}c,\r\n\\end{eqnarray*}$$where fe(p) is the normalized electron spectrum i.e. ∫fe(p)dp = 1 with electron dimension-less momentum $p=\\sqrt{(\\gamma ^2-1)}$, v = βc, where γ is the Lorentz factor and β is the boost factor of energetic electrons. The number of CMB photons which get upscattered from energy x′ to x is given by,\n(13)$$\\begin{eqnarray*}\r\nN(x^{\\prime }-\\gt x)= P(t,p)\\times 2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^2}{({hc})^2}\\frac{x^{\\prime 2}\\mathrm{ d}x^{\\prime }}{e^{x^{\\prime }}-1},\r\n\\end{eqnarray*}$$where P(t, p) is the kernel of the inverse Compton scattering which captures the kinematics of photon scattering with the electrons with electron energy p, $t=\\frac{x}{x^{\\prime }}$. The number of CMB photons within energy x′ and x′ + dx′ is $2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^2}{({hc})^2}\\frac{x^{\\prime 2}dx^{\\prime }}{e^{x^{\\prime }}-1}$ and ∫dtP(t, p) = 1, which conserves the number of photons. The formula for P(t, p) is given by (Enßlin & Kaiser 2000),\n(14)$$\\begin{eqnarray*}\r\nP(t;p)&=&\\frac{-3\\left|(1-t)\\right|}{32p^6t}[1+(10+8p^2+4p^4)t+t^2]+\\frac{3(1+t)}{8p^5}\\nonumber\\\\\r\n&&\\times \\left[\\frac{3+3p^2+p^4}{\\sqrt{1+p^2}}-\\frac{3+2p^2}{2p}(2\\operatorname{arcsinh}{p}-\\left| \\ln {t}\\right|)\\right],\\nonumber\\\\\r\n\\end{eqnarray*}$$The spectral intensity of upscattered photons per frequency, in frequency bin x and x + Δx, is given by,\n(15)$$\\begin{eqnarray*}\r\nj(x)=\\frac{\\int \\int f_{\\rm {e}}(p)\\mathrm{ d}p P(t,p)\\frac{x^{\\prime 2}\\mathrm{ d}x^{\\prime }}{e^{x^{\\prime }}-1}x}{\\Delta x}.\r\n\\end{eqnarray*}$$","Citation Text":["Enßlin & Kaiser (2000)"],"Citation Start End":[[2655,2677]]} {"Identifier":"2021MNRAS.503.5473A__Enßlin_&_Kaiser_2000_Instance_4","Paragraph":"It is well known that energetic electrons can boost the CMB photons to higher energy through inverse Compton scattering creating a distortion in the CMB blackbody spectrum. If the energy distribution of the electrons is non-relativistic and thermal, then the distortion has y-distortion shape (Zeldovich & Sunyaev 1969) (see Section 6 for further discussions on corrections to y-distortion). For relativistic electrons, with a Lorentz factor γ, a photon with energy ϵ gets boosted to γ2ϵ. In this case, the spectral distortion shape will be a function of the electron energy distribution. The intensity of the CMB spectrum per frequency is given by,\n(9)$$\\begin{eqnarray*}\r\nI_{\\nu }(x)=2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^3}{({hc})^2}\\frac{x^3}{e^x-1}=I_0I(x),\r\n\\end{eqnarray*}$$where $I(x)=\\frac{x^3}{e^x-1}$, I(x) is the dimensionless intensity, x is the dimensional frequency which is given by $x=\\frac{E_{\\gamma }}{k_{\\rm {B}}T_{\\rm {CMB}}}$, where Eγ is the energy of photon, kB is the Boltzmann constant, TCMB is the CMB temperature, and other symbols have usual meanings. The intensity of distorted CMB spectrum is independent of redshift for a given population of electrons. The CMB distortion in the optically thin limit can be written as (Zeldovich & Sunyaev 1969; Birkinshaw 1999),\n(10)$$\\begin{eqnarray*}\r\n\\Delta I(x)=(j(x)-i(x))\\tau ,\r\n\\end{eqnarray*}$$where j(x) is the spectral intensity of photons at frequency x after being upscattered while i(x) is the intensity of photons at frequency x before upscattering, τ = σT∫nedl where ne is the electron number density and dl is the line-of-sight width of this electron population. i(x) is non-zero over the range of x where the CMB photons are present. Equation (10) can be recast to include a y-parameter as ΔI(x) = yg(x), where $y=\\frac{\\sigma _{\\rm {T}}}{m_{\\rm {e}}\\rm {c}^2}\\int n_{\\rm {e}}k_{\\rm {B}}\\overset{\\sim }{T_{\\rm {e}}}\\mathrm{ d}l$ with $k_{\\rm {B}}\\overset{\\sim }{T_{\\rm {e}}}=\\frac{P_{\\rm {e}}}{n_{\\rm {e}}}$. Here $\\overset{\\sim }{T_{\\rm {e}}}$ refers to a fictitious temperature scale for a non-thermal distribution to make the equations look suggestively similar to thermal SZ (more details can be found in Enßlin & Kaiser 2000). In order to distinguish non-thermal spectral distortion shape from y-type distortion (the well-known thermal $\\rm {SZ}$ effect), we will refer to non-thermal distortion amplitude as yNT, such that,\n(11)$$\\begin{eqnarray*}\r\n\\Delta I_{\\rm {NT}}(x)=y_{\\rm {NT}}g_{\\rm {NT}}(x),\r\n\\end{eqnarray*}$$where gNT(x) is the spectral distortion function resulting from scattering of the CMB in a non-thermal population of clusters. We use the formalism of Enßlin & Kaiser (2000) to compute gNT(x) and we refer the reader to the paper for details. The pressure for a distribution of relativistic electrons is given by,\n(12)$$\\begin{eqnarray*}\r\nP_{\\rm {e}}=n_{\\rm {e}}\\int \\mathrm{ d}p f_{\\rm {e}}(p)\\frac{1}{3}p{v}(p)m_{\\rm {e}}c,\r\n\\end{eqnarray*}$$where fe(p) is the normalized electron spectrum i.e. ∫fe(p)dp = 1 with electron dimension-less momentum $p=\\sqrt{(\\gamma ^2-1)}$, v = βc, where γ is the Lorentz factor and β is the boost factor of energetic electrons. The number of CMB photons which get upscattered from energy x′ to x is given by,\n(13)$$\\begin{eqnarray*}\r\nN(x^{\\prime }-\\gt x)= P(t,p)\\times 2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^2}{({hc})^2}\\frac{x^{\\prime 2}\\mathrm{ d}x^{\\prime }}{e^{x^{\\prime }}-1},\r\n\\end{eqnarray*}$$where P(t, p) is the kernel of the inverse Compton scattering which captures the kinematics of photon scattering with the electrons with electron energy p, $t=\\frac{x}{x^{\\prime }}$. The number of CMB photons within energy x′ and x′ + dx′ is $2\\frac{(k_{\\rm {B}}T_{\\rm {CMB}})^2}{({hc})^2}\\frac{x^{\\prime 2}dx^{\\prime }}{e^{x^{\\prime }}-1}$ and ∫dtP(t, p) = 1, which conserves the number of photons. The formula for P(t, p) is given by (Enßlin & Kaiser 2000),\n(14)$$\\begin{eqnarray*}\r\nP(t;p)&=&\\frac{-3\\left|(1-t)\\right|}{32p^6t}[1+(10+8p^2+4p^4)t+t^2]+\\frac{3(1+t)}{8p^5}\\nonumber\\\\\r\n&&\\times \\left[\\frac{3+3p^2+p^4}{\\sqrt{1+p^2}}-\\frac{3+2p^2}{2p}(2\\operatorname{arcsinh}{p}-\\left| \\ln {t}\\right|)\\right],\\nonumber\\\\\r\n\\end{eqnarray*}$$The spectral intensity of upscattered photons per frequency, in frequency bin x and x + Δx, is given by,\n(15)$$\\begin{eqnarray*}\r\nj(x)=\\frac{\\int \\int f_{\\rm {e}}(p)\\mathrm{ d}p P(t,p)\\frac{x^{\\prime 2}\\mathrm{ d}x^{\\prime }}{e^{x^{\\prime }}-1}x}{\\Delta x}.\r\n\\end{eqnarray*}$$","Citation Text":["Enßlin & Kaiser 2000"],"Citation Start End":[[3869,3889]]} {"Identifier":"2020MNRAS.498.1801K__Kimura,_Ishimoto_&_Mukai_1997_Instance_1","Paragraph":"Hosler et al. (1957) measured pull-off forces of spherical water-ice particles with radius r0 = 7.366 mm in either air or nitrogen vapour. Prior to their measurements, the two spheres suspended by cotton threads were brought into contact at the position of just touching, resembling the experimental setup of Nakaya & Matsumoto (1954). Therefore, we assume zero indentation indicating that equation (21) applies to their pull-off force measurements, although Hosler et al. (1957) did not report whether or not the particles rotate prior to separation. Since their experiments were carried out in a wide range of temperatures from T = 193 to 273 K and the saturated vapour pressure exponentially decreases with the inverse of the temperature, we may need to consider a variation of relative humidity with the temperature. The saturated vapour pressure psat of water molecules is given by (Kimura, Ishimoto & Mukai 1997)\n(22)$$\\begin{eqnarray*}\r\np_\\mathrm{sat}(T) &=& p_\\infty \\exp \\left({-\\frac{\\Delta H_\\mathrm{s}}{k_\\mathrm{B} T}}\\right) ,\r\n\\end{eqnarray*}$$where $p_\\infty = \\displaystyle \\lim _{T \\rightarrow \\infty } p_\\mathrm{sat}(T)$ and ΔHs denotes the enthalpy of sublimation. According to Prialnik (1992), we assume the following form:\n(23)$$\\begin{eqnarray*}\r\np_\\mathrm{sat}(T) &=& 3.56 \\times {10}^{12}~\\mathrm{Pa} \\, \\exp \\left[{-\\left({\\frac{T}{6141.667~\\mathrm{K}}}\\right)^{-1}}\\right] .\r\n\\end{eqnarray*}$$Fig. 10 depicts the experimental data of Hosler et al. (1957) with open circles for their measurements in air and open squares for those in nitrogen vapour. Also plotted are the temperature variations of equation (21) with the vapour pressure pv = 63.2 in air and 468 Pa in nitrogen vapour. Although the assumption of a constant pv value may be too crude to reproduce the experimental data, equation (21) approximates the experimental data of Hosler et al. (1957) in air and nitrogen vapour within a factor of 2.","Citation Text":["Kimura, Ishimoto & Mukai 1997"],"Citation Start End":[[888,917]]} {"Identifier":"2021ApJ...915...69D__Metzger_et_al._2010_Instance_1","Paragraph":"NR simulations of BH–NS mergers are computationally intensive and typically conclude a few ms after the merger. To follow the post-merger dynamics, the unbound ejecta must be transferred to a hydrodynamics simulation that can accommodate the rapid expansion of the distance scale. Few studies have explored the long-term evolution of the unbound component while incorporating the effect of r-process radioactive heating, which can affect the evolution; as an estimate, the total radioactive energy deposited over the first ∼10−4 d is Erad ∼ 1049 erg (Metzger et al. 2010), which is nontrivial compared to the total kinetic energy \n\n\n\n\n\n\nE\n\n\nkin\n\n\n∼\n\n\nM\n\n\nd\n\n\n\n\nv\n\n\nd\n\n\n2\n\n\n\n\/\n\n2\n∼\nfew\n×\n\n\n10\n\n\n50\n\n\n\n\n erg. Fernández et al. (2015) studied the long-term behavior using Newtonian hydrodynamics with a prescription for r-process heating; they found that heating enlarges the ejecta and smooths small-scale irregularities. This corroborated earlier work in the NS–NS merger context by Rosswog et al. (2014), who used a Newtonian smoothed particle hydrodynamics (SPH) code with heating and a nuclear network and additionally found that the ejecta reaches homology at the ≲1% level by ∼102 s and the abundance of nucleosynthesis products remains roughly unaffected by heating. These two studies used Newtonian merger simulations to initialize the unbound ejecta. Roberts et al. (2017) simulated the hydrodynamic evolution of the BH–NS merger unbound component to generate thermodynamic trajectories as inputs for a nuclear reaction network; since their main aim was to study r-process abundances, they did not study the back-reaction of the nuclear heating on the ejecta structure. Kawaguchi et al. (2021) recently examined the NS–NS post-merger evolution using 2D axisymmetric hydrodynamics with radioactive heating. They found that heating only modestly affects the ejecta structure and hydrodynamics minimally impacts the nucleosynthesis, results that are dependent on the details of the NR handoff. The overall ejecta remains mildly prolate with a lanthanide-present torus and some matter falls back to the BH-disk system.","Citation Text":["Metzger et al. 2010"],"Citation Start End":[[551,570]]} {"Identifier":"2016ApJ...831...39B__Shen_et_al._2016_Instance_1","Paragraph":"From our MUSE \n\n\n\n\n\n and quasar spectra, we can estimate how many of our nebulae would have been missed by NB filter observations because of filter losses. For this thought experiment, we will assume that quasars would have been selected for NB observations if their estimated systemic redshift from corrected broad-line emission (C iv in our case, but typically Mg ii at \n\n\n\n\n\n) would have placed the expected \n\n\n\n\n\n emission at the peak of the NB filter transmission. In reality, the selection is made on a range of systemic redshifts (typically within 500 km s−1 from the filter center), but we will assume that this range is absorbed by the intrinsic scatter in the C iv-corrected redshift estimation (\n\n\n\n\n\n km s−1 at 1σ, Shen et al. 2016). Assuming a typical NB filter width of 3000 km s−1 (FWHM), we can notice from Figure 2 that two nebulae would have been totally missed by NB observations (#2, #6) while for the other five (#1, #10, #11, #12, #16) the displacement between the \n\n\n\n\n\n emission and the filter transmission peak would have resulted in a substantial flux loss that would likely have compromised the detectability of the nebulae, especially in the faintest but most extended regions. However, at least nine nebulae (#3, #4, #5, #7, #8, #9, #13, #14, #15, #17), which is at least 50% of the sample, have \n\n\n\n\n\n emission so close to the estimated systemic redshift that they would not have been missed by NB observations, including also the systemic redshift errors from C iv or Mg ii. This factor is much larger than the 10% detection rate estimated from NB imaging. Therefore, we conclude that filter losses cannot completely explain the discrepancy between MUSE detection rates and those of NB surveys, though they can certainly reduce the NB detection rate significantly. We note that radio-loud quasars typically have much broader \n\n\n\n\n\n emission and therefore filter losses would be even less important for these systems. This may partially explain the higher detection rate of radio-loud nebulae versus radio-quiet ones.","Citation Text":["Shen et al. 2016"],"Citation Start End":[[727,743]]} {"Identifier":"2015ApJ...807..148G__Daigne_&_Mochkovitch_1998_Instance_1","Paragraph":"The fireball model remains the most popular scenario for the gamma-ray burst (GRB) phenomenon (Cavallo & Rees 1978; Goodman 1986; Paczynski 1986; Shemi & Piran 1990; Rees & Mészáros 1992, 1994; Mészáros & Rees 1993). In this model, the GRB central engine is a stellar-mass black hole or a rapidly spinning and highly magnetized neutron star formed by either the collapse of a supermassive star (collapsar; Woosley 1993; MacFadyen & Woosley 1999; Woosley & Heger 2006) or the merger of two compact objects (Paczynski 1986; Fryer et al. 1999; Rosswog 2003). In both cases, the original explosion creates a bipolar collimated jet composed mainly of photons, electrons, positrons, and a small fraction of baryons. The relativistic explosion ejecta within the jet are not homogeneous—they form multiple high density layers, which propagate at various velocities. When the fastest layers catch up with the slowest, the charged particles contained in the layers are accelerated through mildly relativistic collisionless shocks (internal shocks; Rees & Mészáros 1994; Kobayashi et al. 1997; Daigne & Mochkovitch 1998). The particles subsequently cool via emission processes such as synchrotron, Synchrotron Self Compton (SSC), and Inverse Compton (IC). The internal shock phase is usually associated with the so-called GRB prompt emission,17\n\n17\nSee Pe’er (2015) for a recent review of GRB prompt emission.\n mainly observed in the keV−MeV energy range (see, e.g., the spectral catalogs by Gruber et al. 2014; von Kienlin et al. 2014) and usually lasting from a few ms up to several tens to hundreds of seconds. As the ejecta interact with the interstellar medium they slow down via relativistic collisionless shocks (external shocks; Rees & Mészáros 1992; Mészáros & Rees 1993), accelerating charged particles, which then emit non-thermal synchrotron photons. This external shock phase is usually associated with the so-called GRB afterglow emission observed at radio wavelengths up to X-rays and in some cases even up to the GeV regime hours after the prompt phase, and days and even years for the lowest frequencies. The detailed origin of the gamma-ray emission, however, is not fully understood and many theoretical difficulties remain, such as the composition of the jet, the energy dissipation mechanisms, as well as the radiation mechanisms (e.g., Zhang 2011).","Citation Text":["Daigne & Mochkovitch 1998"],"Citation Start End":[[1083,1108]]} {"Identifier":"2015ApJ...807..148GCavallo_&_Rees_1978_Instance_1","Paragraph":"The fireball model remains the most popular scenario for the gamma-ray burst (GRB) phenomenon (Cavallo & Rees 1978; Goodman 1986; Paczynski 1986; Shemi & Piran 1990; Rees & Mészáros 1992, 1994; Mészáros & Rees 1993). In this model, the GRB central engine is a stellar-mass black hole or a rapidly spinning and highly magnetized neutron star formed by either the collapse of a supermassive star (collapsar; Woosley 1993; MacFadyen & Woosley 1999; Woosley & Heger 2006) or the merger of two compact objects (Paczynski 1986; Fryer et al. 1999; Rosswog 2003). In both cases, the original explosion creates a bipolar collimated jet composed mainly of photons, electrons, positrons, and a small fraction of baryons. The relativistic explosion ejecta within the jet are not homogeneous—they form multiple high density layers, which propagate at various velocities. When the fastest layers catch up with the slowest, the charged particles contained in the layers are accelerated through mildly relativistic collisionless shocks (internal shocks; Rees & Mészáros 1994; Kobayashi et al. 1997; Daigne & Mochkovitch 1998). The particles subsequently cool via emission processes such as synchrotron, Synchrotron Self Compton (SSC), and Inverse Compton (IC). The internal shock phase is usually associated with the so-called GRB prompt emission,17\n\n17\nSee Pe’er (2015) for a recent review of GRB prompt emission.\n mainly observed in the keV−MeV energy range (see, e.g., the spectral catalogs by Gruber et al. 2014; von Kienlin et al. 2014) and usually lasting from a few ms up to several tens to hundreds of seconds. As the ejecta interact with the interstellar medium they slow down via relativistic collisionless shocks (external shocks; Rees & Mészáros 1992; Mészáros & Rees 1993), accelerating charged particles, which then emit non-thermal synchrotron photons. This external shock phase is usually associated with the so-called GRB afterglow emission observed at radio wavelengths up to X-rays and in some cases even up to the GeV regime hours after the prompt phase, and days and even years for the lowest frequencies. The detailed origin of the gamma-ray emission, however, is not fully understood and many theoretical difficulties remain, such as the composition of the jet, the energy dissipation mechanisms, as well as the radiation mechanisms (e.g., Zhang 2011).","Citation Text":["Cavallo & Rees 1978"],"Citation Start End":[[95,114]]} {"Identifier":"2015ApJ...807..148GMacFadyen_&_Woosley_1999_Instance_1","Paragraph":"The fireball model remains the most popular scenario for the gamma-ray burst (GRB) phenomenon (Cavallo & Rees 1978; Goodman 1986; Paczynski 1986; Shemi & Piran 1990; Rees & Mészáros 1992, 1994; Mészáros & Rees 1993). In this model, the GRB central engine is a stellar-mass black hole or a rapidly spinning and highly magnetized neutron star formed by either the collapse of a supermassive star (collapsar; Woosley 1993; MacFadyen & Woosley 1999; Woosley & Heger 2006) or the merger of two compact objects (Paczynski 1986; Fryer et al. 1999; Rosswog 2003). In both cases, the original explosion creates a bipolar collimated jet composed mainly of photons, electrons, positrons, and a small fraction of baryons. The relativistic explosion ejecta within the jet are not homogeneous—they form multiple high density layers, which propagate at various velocities. When the fastest layers catch up with the slowest, the charged particles contained in the layers are accelerated through mildly relativistic collisionless shocks (internal shocks; Rees & Mészáros 1994; Kobayashi et al. 1997; Daigne & Mochkovitch 1998). The particles subsequently cool via emission processes such as synchrotron, Synchrotron Self Compton (SSC), and Inverse Compton (IC). The internal shock phase is usually associated with the so-called GRB prompt emission,17\n\n17\nSee Pe’er (2015) for a recent review of GRB prompt emission.\n mainly observed in the keV−MeV energy range (see, e.g., the spectral catalogs by Gruber et al. 2014; von Kienlin et al. 2014) and usually lasting from a few ms up to several tens to hundreds of seconds. As the ejecta interact with the interstellar medium they slow down via relativistic collisionless shocks (external shocks; Rees & Mészáros 1992; Mészáros & Rees 1993), accelerating charged particles, which then emit non-thermal synchrotron photons. This external shock phase is usually associated with the so-called GRB afterglow emission observed at radio wavelengths up to X-rays and in some cases even up to the GeV regime hours after the prompt phase, and days and even years for the lowest frequencies. The detailed origin of the gamma-ray emission, however, is not fully understood and many theoretical difficulties remain, such as the composition of the jet, the energy dissipation mechanisms, as well as the radiation mechanisms (e.g., Zhang 2011).","Citation Text":["MacFadyen & Woosley 1999"],"Citation Start End":[[420,444]]} {"Identifier":"2015ApJ...807..148GPe’er_(2015)_Instance_1","Paragraph":"The fireball model remains the most popular scenario for the gamma-ray burst (GRB) phenomenon (Cavallo & Rees 1978; Goodman 1986; Paczynski 1986; Shemi & Piran 1990; Rees & Mészáros 1992, 1994; Mészáros & Rees 1993). In this model, the GRB central engine is a stellar-mass black hole or a rapidly spinning and highly magnetized neutron star formed by either the collapse of a supermassive star (collapsar; Woosley 1993; MacFadyen & Woosley 1999; Woosley & Heger 2006) or the merger of two compact objects (Paczynski 1986; Fryer et al. 1999; Rosswog 2003). In both cases, the original explosion creates a bipolar collimated jet composed mainly of photons, electrons, positrons, and a small fraction of baryons. The relativistic explosion ejecta within the jet are not homogeneous—they form multiple high density layers, which propagate at various velocities. When the fastest layers catch up with the slowest, the charged particles contained in the layers are accelerated through mildly relativistic collisionless shocks (internal shocks; Rees & Mészáros 1994; Kobayashi et al. 1997; Daigne & Mochkovitch 1998). The particles subsequently cool via emission processes such as synchrotron, Synchrotron Self Compton (SSC), and Inverse Compton (IC). The internal shock phase is usually associated with the so-called GRB prompt emission,17\n\n17\nSee Pe’er (2015) for a recent review of GRB prompt emission.\n mainly observed in the keV−MeV energy range (see, e.g., the spectral catalogs by Gruber et al. 2014; von Kienlin et al. 2014) and usually lasting from a few ms up to several tens to hundreds of seconds. As the ejecta interact with the interstellar medium they slow down via relativistic collisionless shocks (external shocks; Rees & Mészáros 1992; Mészáros & Rees 1993), accelerating charged particles, which then emit non-thermal synchrotron photons. This external shock phase is usually associated with the so-called GRB afterglow emission observed at radio wavelengths up to X-rays and in some cases even up to the GeV regime hours after the prompt phase, and days and even years for the lowest frequencies. The detailed origin of the gamma-ray emission, however, is not fully understood and many theoretical difficulties remain, such as the composition of the jet, the energy dissipation mechanisms, as well as the radiation mechanisms (e.g., Zhang 2011).","Citation Text":["Pe’er (2015)"],"Citation Start End":[[1342,1354]]} {"Identifier":"2015ApJ...807..148GZhang_2011_Instance_1","Paragraph":"The fireball model remains the most popular scenario for the gamma-ray burst (GRB) phenomenon (Cavallo & Rees 1978; Goodman 1986; Paczynski 1986; Shemi & Piran 1990; Rees & Mészáros 1992, 1994; Mészáros & Rees 1993). In this model, the GRB central engine is a stellar-mass black hole or a rapidly spinning and highly magnetized neutron star formed by either the collapse of a supermassive star (collapsar; Woosley 1993; MacFadyen & Woosley 1999; Woosley & Heger 2006) or the merger of two compact objects (Paczynski 1986; Fryer et al. 1999; Rosswog 2003). In both cases, the original explosion creates a bipolar collimated jet composed mainly of photons, electrons, positrons, and a small fraction of baryons. The relativistic explosion ejecta within the jet are not homogeneous—they form multiple high density layers, which propagate at various velocities. When the fastest layers catch up with the slowest, the charged particles contained in the layers are accelerated through mildly relativistic collisionless shocks (internal shocks; Rees & Mészáros 1994; Kobayashi et al. 1997; Daigne & Mochkovitch 1998). The particles subsequently cool via emission processes such as synchrotron, Synchrotron Self Compton (SSC), and Inverse Compton (IC). The internal shock phase is usually associated with the so-called GRB prompt emission,17\n\n17\nSee Pe’er (2015) for a recent review of GRB prompt emission.\n mainly observed in the keV−MeV energy range (see, e.g., the spectral catalogs by Gruber et al. 2014; von Kienlin et al. 2014) and usually lasting from a few ms up to several tens to hundreds of seconds. As the ejecta interact with the interstellar medium they slow down via relativistic collisionless shocks (external shocks; Rees & Mészáros 1992; Mészáros & Rees 1993), accelerating charged particles, which then emit non-thermal synchrotron photons. This external shock phase is usually associated with the so-called GRB afterglow emission observed at radio wavelengths up to X-rays and in some cases even up to the GeV regime hours after the prompt phase, and days and even years for the lowest frequencies. The detailed origin of the gamma-ray emission, however, is not fully understood and many theoretical difficulties remain, such as the composition of the jet, the energy dissipation mechanisms, as well as the radiation mechanisms (e.g., Zhang 2011).","Citation Text":["Zhang 2011"],"Citation Start End":[[2347,2357]]} {"Identifier":"2021AandA...646A..21C__Rocchetto_2017_Instance_1","Paragraph":"Once relatively high-resolution cross sections have been computed, it is reasonably simple to produce k-tables using what is known as the correlated k-distribution method; this method is well described in the literature (see, e.g. Lacis & Oinas 1991; Pierrehumbert 2010), and is extensively used for radiative transfer calculations in the context of planetary and substellar atmospheres (see, e.g. Irwin et al. 2008; Showman et al. 2009; Freedman et al. 2008, 2014; Lee et al. 2019; Mollière et al. 2015; Amundsen et al. 2014; Sharp & Burrows 2007; Malik et al. 2017; Drummond et al. 2016; Phillips et al. 2020). K-tables are generally considered faster (and more accurate for the same \n\n\n\nR\n\n=\n\n\nλ\n\nΔ\nλ\n\n\n\n\n$ R~=~\\frac{\\lambda}{\\Delta \\lambda} $\n\n\n) than cross sections, but they also come with their own assumptions and therefore limitations (see, e.g. Rocchetto 2017). However, these can be assumed to be negligible when compared to other unknowns. The general principle is to order spectral lines within a given spectral bin, producing a smooth cumulative distribution function to represent opacity, which can be more efficiently sampled. The number of points used for sampling within a given spectral bin is determined by a set of Gaussian quadrature points, which are assigned corresponding weights. These are often chosen so as to sample the extremes of the bin more finely so as not to miss the weakest and strongest lines (i.e. the distance between sampling points within a bin is not constant). One of the methods used in this work, for example, is based on the use of Gauss Legendre polynomials (see Sect. 4 for details of the opacities produced for individual retrieval codes). K-tables are produced using a method of opacity sampling which enables low-resolution computations while still taking strong opacity fluctuations at high resolution into account; see, for example, Min (2017). The assumption made for the k-distribution method that the k-coefficients at each Guassian quadrature point are correlated, breaks down for inhomogeneous atmospheres (Lee et al. 2019)","Citation Text":["Rocchetto 2017"],"Citation Start End":[[855,869]]} {"Identifier":"2021MNRAS.508.3125F__Krause_et_al._2017_Instance_1","Paragraph":"Our starting point of modelling the different two-point functions in the 3×2pt data vector is the three-dimensional (3D) non-linear matter power spectrum P(k, z) at a given wavenumber k and redshift z. We obtain it by using either of the Boltzmann solvers CLASS11 or CAMB12 to calculate the linear power spectrum and the HALOFIT fitting formula (Smith et al. 2003) in its updated version (Takahashi et al. 2012) to turn this into the late-time non-linear power spectrum. From this 3D power spectrum, the angular power spectra required for our three two-point functions [cosmic shear (κκ), galaxy–galaxy lensing (δgκ), and galaxy–galaxy clustering (δgδg)] in the Limber approximation are given by (e.g. Limber 1953; Krause et al. 2017):\n(4)$$\\begin{eqnarray*}\r\nC^{ij}_{\\kappa \\kappa }(\\ell) = \\int \\mathrm{ d}\\chi \\frac{q^i_\\kappa (\\chi) q^j_\\kappa (\\chi)}{\\chi ^2} P\\left(\\frac{\\ell +\\frac{1}{2}}{\\chi }, z(\\chi)\\right),\r\n\\end{eqnarray*}$$(5)$$\\begin{eqnarray*}\r\nC^{ij}_{\\delta _\\mathrm{ g} \\kappa }(\\ell) = \\int \\mathrm{ d}\\chi \\frac{q^i_\\delta \\left(\\frac{\\ell +\\frac{1}{2}}{\\chi },\\chi \\right) q^j_\\kappa (\\chi)}{\\chi ^2} P\\left(\\frac{\\ell +\\frac{1}{2}}{\\chi }, z(\\chi)\\right),\r\n\\end{eqnarray*}$$(6)$$\\begin{eqnarray*}\r\nC^{ij}_{\\delta _\\mathrm{ g} \\delta _\\mathrm{ g}}(\\ell) = \\int \\mathrm{ d}\\chi \\frac{q^i_\\delta \\left(\\frac{\\ell +\\frac{1}{2}}{\\chi },\\chi \\right) q^j_\\delta \\left(\\frac{\\ell +\\frac{1}{2}}{\\chi },\\chi \\right)}{\\chi ^2} P\\left(\\frac{\\ell +\\frac{1}{2}}{\\chi }, z(\\chi)\\right)\\ ,\r\n\\end{eqnarray*}$$where χ is the comoving radial distance, i and j denote different combinations of pairs of redshift bins, and the lensing efficiency $q^i_\\kappa$ and the radial weight function for clustering $q^i_\\delta$ are, respectively, given by\n(7)$$\\begin{eqnarray*}\r\nq^i_\\kappa (\\chi) &=& \\frac{3H_0^2 \\Omega _\\mathrm{ m}\\chi }{2a(\\chi)} \\int _{\\chi }^{\\chi _\\mathrm{ h}} \\mathrm{ d}\\chi ^\\prime \\left(\\frac{\\chi ^\\prime - \\chi }{\\chi }\\right) n^i_\\kappa (z(\\chi ^\\prime)) \\frac{\\mathrm{ d} z}{\\mathrm{ d}\\chi ^\\prime } , \\nonumber \\\\\r\nq^i_\\delta (k,\\chi) &=& b^i(k, z(\\chi))\\ n^i_\\delta (z(\\chi)) \\frac{\\mathrm{ d} z}{\\mathrm{ d}\\chi }\\ .\r\n\\end{eqnarray*}$$Here, H0 is the Hubble parameter today, Ωm is the ratio of today’s matter density to today’s critical density of the Universe, a(χ) is the Universe’s scale factor at comoving distance χ, and bi(k, z) is a scale- and redshift-dependent galaxy bias. Furthermore, $n^i_{\\kappa , \\mathrm{ g}}(z)$ denote the redshift distributions of the different DES-Y3 redshift bins of source and lens galaxies, respectively, normalized such that\n(8)$$\\begin{eqnarray*}\r\n\\int \\mathrm{ d}z \\,\\, n^i_{\\kappa , \\mathrm{ g}}(z) = 1\\ .\r\n\\end{eqnarray*}$$Note that on large angular scales the DES-Y3 analysis does not make use of the Limber approximation for galaxy clustering but instead employs the method derived in Fang, Eifler & Krause (2020a).","Citation Text":["Krause et al. 2017"],"Citation Start End":[[715,733]]} {"Identifier":"2015ApJ...809L..20M__Ida_&_Lin_2004_Instance_1","Paragraph":"In this Letter we propose to address these apparent difficulties and account for many of the observed differences between the properties of planets in cool and hot stars by postulating that, in addition to the tidal interaction with existing close-in planets, a large fraction of the stellar hosts—both cool and hot—ingest a hot Jupiter early on in their evolution. This proposal is motivated by the expectation that a large fraction (up to 80% according to Trilling et al. 2002) of solar-type stars possess giant planets during their pre-MS phase, and that a large fraction of the giant planets that form in a protoplanetary disk on scales \n\n\n\n\n\n migrate close to their host star before the disk is dispersed (e.g., Ida & Lin 2004). Numerical simulations incorporating an N-body code and a 1D α-viscosity disk model (Thommes et al. 2008) demonstrated that this behavior can be expected for disks with \n\n\n\n\n\n that are sufficiently massive. The inward planet migration is likely stopped by the strong (\n\n\n\n\n\n kG) protostellar magnetic field that truncates the disk at a radius (rin) of a few stellar radii (e.g., Lin et al. 1996). Gravitational interaction with the disk causes a planet reaching rin to penetrate into the magnetospheric cavity and, if it is massive enough, to undergo eccentricity excitation that can rapidly lead to a collision with the star (e.g., Rice et al. 2008). It was, however, inferred that if Mp is sufficiently small (\n\n\n\n\n\n), the planet would remain stranded at a distance where its orbital period is ∼0.5 of that at rin until well after the gas disk disappears (on a timescale of ∼ 106–107 years). In our proposed scenario, the primordial disk orientations span a broad angular range that is reflected in the orbital orientations of the stranded planets. When the latter are ingested by tidal interaction with the host star (on a timescale \n\n\n\n\n\n Gyr), the absorbed angular momentum is sufficient to align a solar-mass star in that general direction, but not an MS star with \n\n\n\n\n\n K. This is because cool stars have significantly lower angular momenta at the time of ingestion than hot stars as a result of a more efficient magnetic braking process and of a lower moment of inertia. Given the proximity of the stranded HJs (SHJs) to their host stars (\n\n\n\n\n\ndays), they can be expected to have been ingested by the time their parent planetary systems are observed; however, giant planets farther out can continue to interact with their host stars and potentially affect their measured obliquities. In our simplified formulation, we model the SHJs using as parameters their characteristic mass MSHJ and the fraction p of systems that initially harbored an SHJ. By comparing the predictions of this model with the observational data, we infer \n\n\n\n\n\n and \n\n\n\n\n\n.","Citation Text":["Ida & Lin 2004"],"Citation Start End":[[717,731]]} {"Identifier":"2016ApJ...825..144W__Fechner_&_Reimers_2007_Instance_1","Paragraph":"For the five He ii sightlines recorded at sufficiently high spectral resolution (\n\n\n\n\n\n), coeval spectra of the optically thin H i Lyα forest provide estimates of the number density ratio \n\n\n\n\n\n. In a fully reionized IGM \n\n\n\n\n\n probes the spectral shape of the UV background and its source population (e.g., Miralda-Escudé & Ostriker 1990; Madau & Meiksin 1994; Fardal et al. 1998; Haardt & Madau 2012), so observational constraints are of great astrophysical interest. The patches of strong quasi-continuous He ii absorption at \n\n\n\n\n\n typically require \n\n\n\n\n\n (Reimers et al. 1997, 2005; Heap et al. 2000; Smette et al. 2002; Shull et al. 2010; Syphers & Shull 2014), whereas the \n\n\n\n\n\n He ii Lyα forest revealed order-of-magnitude fluctuations around \n\n\n\n\n\n on scales down to ∼1 Mpc (Kriss et al. 2001; Shull et al. 2004; Zheng et al. 2004b; Fechner et al. 2006; Fechner & Reimers 2007). However, these studies were affected by various systematics, most importantly by uncertainty in the zero level of the FUSE data (Fechner & Reimers 2007) and H i continuum uncertainty (e.g., Heap et al. 2000). We recently showed that by accounting for H i continuum systematics with realistic mock spectra from numerical simulations, the higher-quality COS spectra from the two sightlines sampling \n\n\n\n\n\n are consistent with \n\n\n\n\n\n without the need for fluctuations exceeding a factor of two (McQuinn & Worseck 2014). This implies that in the post-reionization IGM, radiative transfer effects (Maselli & Ferrara 2005; Tittley & Meiksin 2007; Meiksin & Tittley 2012) or Poisson fluctuations in the number density of quasars (Bolton et al. 2006) generate only modest UV background fluctuations. However, all existing inferences on the epoch of He ii reionization have been tempered by the very small sample of sightlines available to study He ii Lyα absorption. Indeed, expanding the data set has been the most pressing need to advance our understanding of He ii reionization.","Citation Text":["Fechner & Reimers 2007"],"Citation Start End":[[865,887]]} {"Identifier":"2016ApJ...825..144W__Fechner_&_Reimers_2007_Instance_2","Paragraph":"For the five He ii sightlines recorded at sufficiently high spectral resolution (\n\n\n\n\n\n), coeval spectra of the optically thin H i Lyα forest provide estimates of the number density ratio \n\n\n\n\n\n. In a fully reionized IGM \n\n\n\n\n\n probes the spectral shape of the UV background and its source population (e.g., Miralda-Escudé & Ostriker 1990; Madau & Meiksin 1994; Fardal et al. 1998; Haardt & Madau 2012), so observational constraints are of great astrophysical interest. The patches of strong quasi-continuous He ii absorption at \n\n\n\n\n\n typically require \n\n\n\n\n\n (Reimers et al. 1997, 2005; Heap et al. 2000; Smette et al. 2002; Shull et al. 2010; Syphers & Shull 2014), whereas the \n\n\n\n\n\n He ii Lyα forest revealed order-of-magnitude fluctuations around \n\n\n\n\n\n on scales down to ∼1 Mpc (Kriss et al. 2001; Shull et al. 2004; Zheng et al. 2004b; Fechner et al. 2006; Fechner & Reimers 2007). However, these studies were affected by various systematics, most importantly by uncertainty in the zero level of the FUSE data (Fechner & Reimers 2007) and H i continuum uncertainty (e.g., Heap et al. 2000). We recently showed that by accounting for H i continuum systematics with realistic mock spectra from numerical simulations, the higher-quality COS spectra from the two sightlines sampling \n\n\n\n\n\n are consistent with \n\n\n\n\n\n without the need for fluctuations exceeding a factor of two (McQuinn & Worseck 2014). This implies that in the post-reionization IGM, radiative transfer effects (Maselli & Ferrara 2005; Tittley & Meiksin 2007; Meiksin & Tittley 2012) or Poisson fluctuations in the number density of quasars (Bolton et al. 2006) generate only modest UV background fluctuations. However, all existing inferences on the epoch of He ii reionization have been tempered by the very small sample of sightlines available to study He ii Lyα absorption. Indeed, expanding the data set has been the most pressing need to advance our understanding of He ii reionization.","Citation Text":["Fechner & Reimers 2007"],"Citation Start End":[[1019,1041]]} {"Identifier":"2017ApJ...837..130V__Bragaglia_&_Tosi_2006_Instance_1","Paragraph":"In order to improve the census of X-ray sources in old open clusters, we are undertaking a survey with Chandra of open clusters with ages between 3.5 and 10 Gyr. The observations are designed to reach a limiting luminosity of \n\n\n\n\n\n (0.3–7 keV), or better, at the distance of the clusters. As part of this survey, we have carried out the first X-ray study of Collinder 261 (Cr 261), and we present the results of our efforts in this paper. With an estimated age of 6–7 Gyr (Bragaglia & Tosi 2006), Cr 261 is one of the oldest open clusters in the Galaxy, being superseded in age by NGC 6791 (8–9 Gyr) and Berkeley 17 (8.5–10 Gyr) only. The cluster metallicity is close to solar (Drazdauskas et al. 2016), and reported values for the distance and reddening lie between 2.2–2.7 kpc and \n\n\n\n\n\n, respectively (see, e.g., Gozzoli et al. 1996; Carraro et al. 1999; Bragaglia & Tosi 2006), with a higher value of the reddening considered more plausible (Friel et al. 2003). In this paper, we adopt a distance of 2.5 kpc and \n\n\n\n\n\n, unless stated otherwise. The latter corresponds to a V-band extinction AV = 1.05 for the canonical ratio \n\n\n\n\n\n, and a neutral hydrogen column density \n\n\n\n\n\n (Predehl & Schmitt 1995). The Galactic coordinates of Cr 261 are \n\n\n\n\n\n, \n\n\n\n\n\n due to its low Galactic latitude and location toward the bulge, the number of foreground and background stars projected onto the cluster is high. Cluster membership is poorly constrained for the majority of stars in the field. Cr 261 is included in the star cluster catalog of Kharchenko et al. (2013), which lists structural parameters such as the overall size of the cluster and the radius of its central region. In this work, we present an estimate for the half-mass radius rh and the approximate mass of Cr 261, which, to our knowledge, have not been reported in the literature before. These parameters facilitate a uniform comparison with the X-ray properties of other old Galactic clusters.","Citation Text":["Bragaglia & Tosi 2006"],"Citation Start End":[[474,495]]} {"Identifier":"2017ApJ...837..130V__Bragaglia_&_Tosi_2006_Instance_2","Paragraph":"In order to improve the census of X-ray sources in old open clusters, we are undertaking a survey with Chandra of open clusters with ages between 3.5 and 10 Gyr. The observations are designed to reach a limiting luminosity of \n\n\n\n\n\n (0.3–7 keV), or better, at the distance of the clusters. As part of this survey, we have carried out the first X-ray study of Collinder 261 (Cr 261), and we present the results of our efforts in this paper. With an estimated age of 6–7 Gyr (Bragaglia & Tosi 2006), Cr 261 is one of the oldest open clusters in the Galaxy, being superseded in age by NGC 6791 (8–9 Gyr) and Berkeley 17 (8.5–10 Gyr) only. The cluster metallicity is close to solar (Drazdauskas et al. 2016), and reported values for the distance and reddening lie between 2.2–2.7 kpc and \n\n\n\n\n\n, respectively (see, e.g., Gozzoli et al. 1996; Carraro et al. 1999; Bragaglia & Tosi 2006), with a higher value of the reddening considered more plausible (Friel et al. 2003). In this paper, we adopt a distance of 2.5 kpc and \n\n\n\n\n\n, unless stated otherwise. The latter corresponds to a V-band extinction AV = 1.05 for the canonical ratio \n\n\n\n\n\n, and a neutral hydrogen column density \n\n\n\n\n\n (Predehl & Schmitt 1995). The Galactic coordinates of Cr 261 are \n\n\n\n\n\n, \n\n\n\n\n\n due to its low Galactic latitude and location toward the bulge, the number of foreground and background stars projected onto the cluster is high. Cluster membership is poorly constrained for the majority of stars in the field. Cr 261 is included in the star cluster catalog of Kharchenko et al. (2013), which lists structural parameters such as the overall size of the cluster and the radius of its central region. In this work, we present an estimate for the half-mass radius rh and the approximate mass of Cr 261, which, to our knowledge, have not been reported in the literature before. These parameters facilitate a uniform comparison with the X-ray properties of other old Galactic clusters.","Citation Text":["Bragaglia & Tosi 2006"],"Citation Start End":[[859,880]]} {"Identifier":"2015AandA...581A..73L__Faherty_et_al._(2014)_Instance_1","Paragraph":"We determined the luminosity of the L and T components using J-, H-, and K-band bolometric corrections (Golimowski et al. 2004b; Nakajima et al. 2004; Vrba et al. 2004) valid for field dwarfs and the spectral intervals L6–L8 (Luhman 16A) and L9–T1 (Luhman 16B), which accounts for the spectral types of the pair members and their associated uncertainties. Note that the H-band bolometric correction (BC) shows the smallest dispersion among the three bands. We also used a solar bolometric luminosity of 4.73 mag and the trigonometric distance of 2.02 ± 0.02 pc determined for the system by Boffin et al. (2014). The near-infrared magnitudes of each pair member provided by Burgasser et al. (2013) and Kniazev et al. (2013) were averaged. We derived the following values: log L\/L⊙ = −4.68 ± 0.08 (L component) and −4.66 ± 0.08 dex (T component). The luminosity error bars consider the uncertainties in the photometry (typically ±0.03 mag), the distance modulus (±0.02 mag), and the corresponding BCs (typically ±0.15 mag for J and K, and ±0.08 for H). Our determination for the L component broadly agrees with Faherty et al. (2014), who found log L\/L⊙ = −4.67 ± 0.04 dex after the integration over their optical (0.6−0.9 μm) and near-infrared (0.8−2.5 μm) spectra supplemented with synthetic spectra for wavelengths longer than 2.5 μm. This supports the reliability of the BCs for these spectral types. Our luminosity determination for the T component is consistent with that of Faherty et al. (2014, −4.71 ± 0.10 at the 1σ level, although our measurement suggests a slightly brighter luminosity. In a similar manner as described in Faherty et al. (2014), we also integrated our X-Shooter spectra and found that the L and T dwarfs have nearly identical luminosity, with the T object being 0.01 dex more luminous than the L dwarf, in agreement with the luminosities inferred from the BCs. The T component has been reported to show stronger variability than the L source at optical and near-infrared wavelengths with peak-to-peak amplitudes of 11−13.5% in continuous observations and strong night-to-night evolution according to Gillon et al. (2013), Biller et al. (2013), and Burgasser et al. (2014). This might affect the luminosity determination for this particular dwarf. To account for the observed variability amplitude, an uncertainty of ±0.05 dex should be added to the error bar in the luminosity derivation of the T pair member, thus yielding log L\/L⊙ = −4.66 ± 0.13 dex. One striking result is that, despite the differing spectral classifications, both objects, Luhman 16A and B, have consistent L\/L⊙ values at the 1σ level. ","Citation Text":["Faherty et al. (2014)"],"Citation Start End":[[1114,1135]]} {"Identifier":"2015AandA...581A..73L__Faherty_et_al._(2014)_Instance_2","Paragraph":"We determined the luminosity of the L and T components using J-, H-, and K-band bolometric corrections (Golimowski et al. 2004b; Nakajima et al. 2004; Vrba et al. 2004) valid for field dwarfs and the spectral intervals L6–L8 (Luhman 16A) and L9–T1 (Luhman 16B), which accounts for the spectral types of the pair members and their associated uncertainties. Note that the H-band bolometric correction (BC) shows the smallest dispersion among the three bands. We also used a solar bolometric luminosity of 4.73 mag and the trigonometric distance of 2.02 ± 0.02 pc determined for the system by Boffin et al. (2014). The near-infrared magnitudes of each pair member provided by Burgasser et al. (2013) and Kniazev et al. (2013) were averaged. We derived the following values: log L\/L⊙ = −4.68 ± 0.08 (L component) and −4.66 ± 0.08 dex (T component). The luminosity error bars consider the uncertainties in the photometry (typically ±0.03 mag), the distance modulus (±0.02 mag), and the corresponding BCs (typically ±0.15 mag for J and K, and ±0.08 for H). Our determination for the L component broadly agrees with Faherty et al. (2014), who found log L\/L⊙ = −4.67 ± 0.04 dex after the integration over their optical (0.6−0.9 μm) and near-infrared (0.8−2.5 μm) spectra supplemented with synthetic spectra for wavelengths longer than 2.5 μm. This supports the reliability of the BCs for these spectral types. Our luminosity determination for the T component is consistent with that of Faherty et al. (2014, −4.71 ± 0.10 at the 1σ level, although our measurement suggests a slightly brighter luminosity. In a similar manner as described in Faherty et al. (2014), we also integrated our X-Shooter spectra and found that the L and T dwarfs have nearly identical luminosity, with the T object being 0.01 dex more luminous than the L dwarf, in agreement with the luminosities inferred from the BCs. The T component has been reported to show stronger variability than the L source at optical and near-infrared wavelengths with peak-to-peak amplitudes of 11−13.5% in continuous observations and strong night-to-night evolution according to Gillon et al. (2013), Biller et al. (2013), and Burgasser et al. (2014). This might affect the luminosity determination for this particular dwarf. To account for the observed variability amplitude, an uncertainty of ±0.05 dex should be added to the error bar in the luminosity derivation of the T pair member, thus yielding log L\/L⊙ = −4.66 ± 0.13 dex. One striking result is that, despite the differing spectral classifications, both objects, Luhman 16A and B, have consistent L\/L⊙ values at the 1σ level. ","Citation Text":["Faherty et al. (2014"],"Citation Start End":[[1484,1504]]} {"Identifier":"2015AandA...581A..73L__Faherty_et_al._(2014)_Instance_3","Paragraph":"We determined the luminosity of the L and T components using J-, H-, and K-band bolometric corrections (Golimowski et al. 2004b; Nakajima et al. 2004; Vrba et al. 2004) valid for field dwarfs and the spectral intervals L6–L8 (Luhman 16A) and L9–T1 (Luhman 16B), which accounts for the spectral types of the pair members and their associated uncertainties. Note that the H-band bolometric correction (BC) shows the smallest dispersion among the three bands. We also used a solar bolometric luminosity of 4.73 mag and the trigonometric distance of 2.02 ± 0.02 pc determined for the system by Boffin et al. (2014). The near-infrared magnitudes of each pair member provided by Burgasser et al. (2013) and Kniazev et al. (2013) were averaged. We derived the following values: log L\/L⊙ = −4.68 ± 0.08 (L component) and −4.66 ± 0.08 dex (T component). The luminosity error bars consider the uncertainties in the photometry (typically ±0.03 mag), the distance modulus (±0.02 mag), and the corresponding BCs (typically ±0.15 mag for J and K, and ±0.08 for H). Our determination for the L component broadly agrees with Faherty et al. (2014), who found log L\/L⊙ = −4.67 ± 0.04 dex after the integration over their optical (0.6−0.9 μm) and near-infrared (0.8−2.5 μm) spectra supplemented with synthetic spectra for wavelengths longer than 2.5 μm. This supports the reliability of the BCs for these spectral types. Our luminosity determination for the T component is consistent with that of Faherty et al. (2014, −4.71 ± 0.10 at the 1σ level, although our measurement suggests a slightly brighter luminosity. In a similar manner as described in Faherty et al. (2014), we also integrated our X-Shooter spectra and found that the L and T dwarfs have nearly identical luminosity, with the T object being 0.01 dex more luminous than the L dwarf, in agreement with the luminosities inferred from the BCs. The T component has been reported to show stronger variability than the L source at optical and near-infrared wavelengths with peak-to-peak amplitudes of 11−13.5% in continuous observations and strong night-to-night evolution according to Gillon et al. (2013), Biller et al. (2013), and Burgasser et al. (2014). This might affect the luminosity determination for this particular dwarf. To account for the observed variability amplitude, an uncertainty of ±0.05 dex should be added to the error bar in the luminosity derivation of the T pair member, thus yielding log L\/L⊙ = −4.66 ± 0.13 dex. One striking result is that, despite the differing spectral classifications, both objects, Luhman 16A and B, have consistent L\/L⊙ values at the 1σ level. ","Citation Text":["Faherty et al. (2014)"],"Citation Start End":[[1638,1659]]} {"Identifier":"2019MNRAS.486.5838R__Kruijssen_et_al._2019a_Instance_1","Paragraph":"Despite the differences between the methods used to determine GC ages, they paint a similar picture: GC populations are typically older than field stars, as they mostly formed before the peak of the cosmic star formation history (z ≃ 2, Madau & Dickinson 2014), and metal-poor GCs seem to have formed coevally to or earlier than the metal-rich ones. In the Milky Way, the population of massive (M > 105 M⊙) GCs with metallicities −2.5 [Fe\/H] −0.5 is ≃12.2 Gyr old (z ∼ 4, Kruijssen et al. 2019a, based on measurements from Forbes & Bridges 2010; Dotter et al. 2010; Dotter, Sarajedini & Anderson 2011; VandenBerg et al. 2013), which is older than the inferred mean star formation time based on the star formation history of the Milky Way, τf = 10.5 ± 1.5 Gyr (Snaith et al. 2014). Despite the relatively large uncertainties (∼1 Gyr), several studies find an age–metallicity relation among the GCs in the Milky Way, with metal-poor GCs being the oldest and younger objects having higher metallicities. The exact age offset between both subpopulations depends on the catalogue considered and the metallicity range, but overall metal-poor GCs are found to be coeval to or older (by up to ∼1.25 Gyr) than the metal-rich subpopulation within the uncertainties (considering $\\rm [Fe\/H]\\gtrless -1.2$ between the metal-poor and metal-rich subpopulations; Dotter et al. 2010; Forbes & Bridges 2010; Dotter et al. 2011; VandenBerg et al. 2013). Subsamples of GCs in different metallicity intervals are also observed to have radial age gradients, as seen in M31 (Beasley et al. 2005) and in 11 early-type galaxies from the SLUGGS survey (Forbes et al. 2015). The implied differences in formation epoch have been proposed to explain the observed differences in spatial distributions and kinematics between these metallicity GC subpopulations (Brodie & Strader 2006), and some authors also suggest they indicate different formation mechanisms (Griffen et al. 2010).","Citation Text":["Kruijssen et al. 2019a"],"Citation Start End":[[474,496]]} {"Identifier":"2022MNRAS.516.5887F__Chen,_Donoho_&_Saunders_1998_Instance_1","Paragraph":"The first step of the main process aims at selecting as few modes as possible to model the magnetic topology of the star, using sparse approximation. We begin by combining the sequence of observed Stokes V profiles in sliding subsets of n consecutive profiles (with n ≪ q, the total number of observed profiles) and we associate each group of profiles to the mean date over the corresponding subset. This date is then converted into a rotation cycle using the stellar rotation period, assumed to be known or derived from the GPR modelling of the longitudinal field (see Section 2.3.2). We assume that the magnetic field we want to reconstruct is not too strong, to ensure that the relation between the Stokes V data and the magnetic map remains linear. We come back in Section 5 on this limitation. Our problem thus amounts to look for the simplest linear combination of data base profiles that can reproduce the selected subset of observations to a given precision σ. In practice, this is achieved through sparse approximation (e.g. Mallat & Zhang 1993; Tibshirani 1996; Donoho & Elad 2003; Donoho, Elad & Temlyakov 2006), this problem being known as Basis Pursuit denoizing (Chen, Donoho & Saunders 1998) and formalized as follows:\n(9)$$\\begin{eqnarray}\r\n\\rm minimize \\, \\, \\, \\Vert \\boldsymbol {X}\\Vert _1 \\, \\, \\, \\rm s.t. \\, \\, \\, \\Vert \\boldsymbol{ \\mathsf {A}}\\boldsymbol{X}-\\boldsymbol{ \\boldsymbol {B}}\\Vert _2 \\le \\sigma ,\r\n\\end{eqnarray}$$where $\\boldsymbol{ B}$ is a vector containing the N data points in the group of n profiles, $\\boldsymbol{ \\mathsf {A}}$ the dictionary, an N × p matrix for which each column contains the spectral signatures of each mode (included in the data base) taken at the observed phases, and σ the level at which we wish the data to be fitted. The components Xi of the vector $\\boldsymbol {X}$ are directly associated with the modes to be reconstructed, i.e. proportional to the real or imaginary part of one of the αℓ,m, βℓ,m, and γℓ,m coefficients describing the field (up to a degree ℓmax ). Taking into account the noise in the data, the previous problem can be generalized by including an N × N diagonal matrix $\\boldsymbol{ \\mathsf {W}}$ containing the inverse of the errors on the spectral points. Problem (9) then becomes:\n(10)$$\\begin{eqnarray}\r\n\\rm minimize \\, \\, \\, \\Vert \\boldsymbol {X}\\Vert _1 \\, \\, \\, \\rm s.t. \\, \\, \\, \\Vert\\boldsymbol{ \\mathsf {W}}(\\boldsymbol{ \\mathsf {A}}\\boldsymbol{X}- \\boldsymbol {B})\\Vert _2 \\le \\tau\r\n\\end{eqnarray}$$with τ2 being the chi-square (χ2) level at which we wish the data to be fitted.","Citation Text":["Chen, Donoho & Saunders 1998"],"Citation Start End":[[1177,1205]]} {"Identifier":"2018ApJ...856..107S__Visbal_&_Loeb_2010_Instance_1","Paragraph":"CO emission is derived for each object in the catalog by converting infrared luminosity to CO line strength with the well-established LIR–\n\n\n\n\n\n correlation (e.g., Carilli & Walter 2013, hereafter CW13; Greve et al. 2014, hereafter G14; Dessauges-Zavadsky et al. 2015). We can then use the measured stellar mass functions of galaxies at 0 z 2 to calculate the power of CO line foregrounds, with the ability of monitoring different subsets (e.g., different stellar mass bins, quiescent versus star-forming galaxies, etc.) Now the total mean intensity of CO contamination can be expressed as\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n, 3 ≤ Jupp ≤ 6, representing all CO transitions acting as foregrounds and \n\n\n\n\n\n being the stellar mass function measured by the COSMOS\/UltraVISTA Survey (Muzzin et al. 2013b). \n\n\n\n\n\n represents an evolving mass cut that measures the depth of foreground masking (see Section 4.3 for a detailed discussion) and is set to \n\n\n\n\n\n when no masking is applied. The factor \n\n\n\n\n\n accounts for the mapping of frequency into distance along the line of sight (Visbal & Loeb 2010). The comoving radial distance χ, the comoving angular diameter distance DA, and the luminosity distance DL are related by \n\n\n\n\n\n. In the presence of scatter (as is always the case), the expectation value of a function \n\n\n\n\n\n of CO luminosity at a best-fit \n\n\n\n\n\n given by simstack can be written as\n8\n\n\n\n\n\nand\n9\n\n\n\n\n\nwhere\n10\n\n\n\n\n\nis derived from the best-fit \n\n\n\n\n\n correlation, with rJ being some scaling factor for different J. Consequently, in the presence of scatter, Equation (7) becomes \n\n\n\n\n\n, which describes the expectation value of the total CO mean intensity, averaged over the probability distribution of \n\n\n\n\n\n as specified by μ and \n\n\n\n\n\n. In our calculation, we consider two prescriptions: (i) CW13, who give α = 1.37 ± 0.04, β = −1.74 ± 0.40, and scaling relations appropriate for sub-millimeter galaxies which are used to convert to transitions higher than \n\n\n\n\n\n, and (ii) G14, who provide α and β coefficients for each individual J transition (i.e., rJ = 1) based on samples of low-z ultra-luminous infrared galaxies and high-z dusty star-forming galaxies comparable to CW13. Since the total CO foreground consists of multiple J transitions, we deem the G14 prescription more appropriate for our purposes, because it treats both the slope and intercept as free parameters when fitting to galaxies observed in different J. Henceforth, we present our results based on the G14 model unless otherwise stated.","Citation Text":["Visbal & Loeb 2010"],"Citation Start End":[[1061,1079]]} {"Identifier":"2018AandA...620L...8H__Vokrouhlický_et_al._(2017)_Instance_1","Paragraph":"We applied the convex inversion method of Kaasalainen et al. (2001) and Kaasalainen & Torppa (2001) to the optical dataset of 70 light curves (described in Appendix A and listed in Table A.1) following exactly the procedure of Hanuš et al. (2016). Specifically, we scanned rotation periods in the proximity of the expected value while testing ten initial pole solutions for each sampled period. Four poles were selected on the equator with 90° difference in longitude, and three poles in each hemisphere with the latitude ±60° and with 120° difference in longitude. We assumed that all solutions within a 3σ uncertainty interval had \n\n\n\n\nχ\n2\n\n\n\n(\n1\n+\n3\n\n\n2\n\/\nν\n\n\n)\n\n\n\nχ\nmin\n2\n\n\n\n$ \\chi^2 < (1+3\\sqrt{2\/\\nu})\\,\\chi^{2}_{\\mathrm{min}} $\n\n\n\n, where \n\n\n\n\nχ\n\nmin\n\n2\n\n\n\n$ \\chi _{{\\rm{min}}}^2 $\n\n\n is the χ2 of the best-fitting solution and ν is the number of degrees of freedom. This threshold to consider the solution acceptable was used before in Vokrouhlický et al. (2017) or Ďurech et al. (2018)\n3 and corresponded to a ∼7% increase in \n\n\n\n\nχ\n\nmin\n\n2\n\n\n\n$ \\chi _{{\\rm{min}}}^2 $\n\n\n value. Only the best-fitting solution fulfilled the 3σ condition on the χ2. To further verify that the best-fitting solution was the only one acceptable, we also visually inspected the light-curve fit with the second-best-fitting period, similarly as in Hanuš et al. (2016), see their Figs. 3 and 4 for illustration. This solution was already inconsistent with several individual light-curves. Therefore, we considered the difference in χ2 as significant and rejected all periods except for the best-fitting one. Next, we ran the convex inversion with the unique period and multiple pole orientations (isotropically distributed on a sphere with a 30° difference) as starting points of the optimization procedure and derived a single solution within the 3σ uncertainty interval defined above. Again, we visually inspected the light-curve fit with the second-best-fitting pole orientation and rejected this solution and also considered all other solutions as non-acceptable. The final solution is given in Table 1 together with the previous determinations. It is notable that our analysis and the recent study of Kim et al. (2018) provide for the first time a unique shape and spin solution that is consistent with the preferred solution of Hanuš et al. (2016). There are two differences between our old and revised models: (i) the relative dimension along the rotation axis (or the c\/a ratio) is now smaller by ∼10%, which is expected because this dimension is generally the least constrained by the optical data, and (ii) the pole directions are about 8° apart.","Citation Text":["Vokrouhlický et al. (2017)"],"Citation Start End":[[944,970]]} {"Identifier":"2022ApJ...937...31G__Kamraj_et_al._2022_Instance_1","Paragraph":"We note that Mrk 590 does not fit this description. The soft excesses in obs1 and obs2 were described by a nonrotating black hole (r\nin fixed at 6r\n\ng\n) and a slightly ionized accretion disk. This result contradicts recent studies of other type 1 AGNs, where the reflection model favors a rotating black hole and the inner part of the disk approaches the innermost stable circular orbit (1.25r\n\ng\n; García et al. 2019; Ghosh & Laha2020, 2021). We note a significant increase in disk ionization between observations (from \n\n\n\nlogξ=0.52−0.30+0.77\n\n in obs2 to \n\n\n\nlogξ∼3\n\n in obs3). We also found a significant decrease in Γ value from obs1 to obs8, indicating a spectral hardening. For obs7 and obs8, we found a well-constrained, high-energy cutoff of \n\n\n\n92−25+55keV\n\n and \n\n\n\n60−8+10keV\n\n, respectively, better described by the relxill model. Although these values are relatively lower compared to other Seyfert 1 galaxies (200–300 keV; Ghosh et al. 2016; Ricci et al. 2017; Fabian et al. 2017; Akylas & Georgantopoulos 2021), similar low values of E\ncut have been found in recent sample studies of Swift\/BAT-selected AGNs (Kamraj et al. 2022). This low-energy cutoff may indicate a decrease in the plasma temperature of the corona only if it was higher during obs1 and obs2. But we cannot test this scenario owing to the nonavailability of data beyond 10 keV. Now hard X-ray photons illuminate the disk, so less energetic photons mean low illumination. However, we note that the disk is still moderately ionized and is capable of Ross & Fabian (2005) producing fluorescent emission lines. More importantly, we did not find any broad Fe emission line or Compton hump in any of the source spectra. The reflected flux and reflection fraction do not show statistically significant variation and remain within the 3σ value. When we plotted the soft excess flux versus the power-law flux (2–10 keV), we did not find any significant correlation (see Figure 8). This result is consistent with Boissay et al. (2016), where the shape of reflection at hard X-rays stays constant when the soft excess varies, showing an absence of a link between reflection and soft excess. In Mrk 590, the power law, the Fe line emission, and UV monochromatic flux follow the same temporal pattern (Figure 3). This result suggests that the disk and corona are most likely evolving together. However, the soft excess is not responding to this change in disk–corona properties. Hence, the soft excess emission observed in Mrk 590 is not due to ionized reflection from the disk.","Citation Text":["Kamraj et al. 2022"],"Citation Start End":[[1126,1144]]} {"Identifier":"2017ApJ...836..183S__Mateos_et_al._2015_Instance_1","Paragraph":"We also note that we do not have reason to think that we may be underestimating the stellar mass of Was 49b due to dust obscuration. We examined this possibility by measuring the K-band light ratio of Was 49b to Was 49a using an image from the UKIRT Infrared Deep Sky Survey (UKIDSS; Lawrence et al. 2007), taken on 2010 February 27. At 2.2 μm the AGN is manifest as a dominant, unresolved source in Was 49b (Figure 6, left). Because of the dominance of the AGN and the shallowness of the UKIDSS image, it was difficult to model any extended emission in Was 49b using galfit, as was done for the DCT images. We instead subtracted the AGN and measured the remaining emission by determining the expected K-band AGN luminosity given its intrinsic luminosity found in Section 3.1. Using five bright stars within a few arcminutes of Was 49, we made an empirical template of the PSF. We found that we could accurately model the stars in the image with a PSF with three Gaussian components. With our PSF template, we fit the unresolved source in Was 49b, allowing only the amplitude and position to vary (Figure 6, middle). We found a PSF K-band magnitude of 13.52, which corresponds to \n\n\n\n\n\n erg s−1. Before subtracting this unresolved source from the K-band image, we performed a check to ensure that it is consistent with the expected AGN emission. Using the value of AV ∼ 12 for the direct AGN continuum calculated above and the extinction curve of Cardelli et al. (1989), we found AK ∼ 1.3, which implies an intrinsic AGN luminosity of LK ∼ 1044 erg s−1. If we assume that the intrinsic spectral energy distribution is approximately flat in the near-IR to the mid-IR for luminous AGNs, then we can use LK ∼ L6 μm ∼ \n\n\n\n\n\n (e.g., Mateos et al. 2015) to calculate \n\n\n\n\n\n erg s−1, consistent with the intrinsic value, given the scatter on EB–V\/\n\n\n\n\n\n and L6 μm\/\n\n\n\n\n\n. As the observed unresolved source in Was 49b is consistent with expectations for the AGN, we subtracted it from the background-subtracted K-band image and photometered the remaining emission in Was 49b for comparison with Was 49a. We did not attempt to model any contribution to the K-band emission from the AGN in Was 49a, as the faint, soft X-ray source in Was 49a (Section 3.1) suggests that the 2–10 keV luminosity and therefore the expected K-band luminosity are negligible. We used the position and inclination angle for the disk of Was 49a (Table 2) to build an elliptical isophotal profile of Was 49a, which we interpolated across the position of Was 49b using a low-order polynomial and by taking the median isophotal value. Subtracting this profile and estimating the variance from a source-free region in the UKIDSS image, we found that the K-band light ratio is consistent with the Was 49 system being a \n\n\n\n\n\n merger, where the confidence intervals are ∼90%. We emphasize that these confidence intervals assume that the AGN has been accurately subtracted from Was 49b. This may not be the case, as there is scatter in the relationship between the intrinsic X-ray luminosity and intrinsic IR luminosity of AGNs. If our model of the AGN overestimated the observed K-band luminosity of the AGN, then the K-band light ratio would be somewhat lower. It is less likely, however, that our model underestimated the observed K-band luminosity of the AGN, as increasing the modeled luminosity would quickly lead to negative flux values when subtracting it from the K-band data. With these considerations, we consider Was 49 to be a minor merger, with a mass ratio between ∼1:7 and ∼1:15.","Citation Text":["Mateos et al. 2015"],"Citation Start End":[[1728,1746]]} {"Identifier":"2022ApJ...939...22Z__Allain_et_al._1996a_Instance_1","Paragraph":"How does excitation affect 6.2 μm\/7.7 μm? A harder illuminating spectrum contains more UV photons at higher energy and hence directly enhances PAH emission at shorter wavelengths relative to that at longer wavelengths (Draine et al. 2021; Rigopoulou et al. 2021). If this were true, the 11.3 μm\/7.7 μm band ratio should decrease strictly with increasing excitation, because a harder radiation field preferentially enhances PAH emission at shorter wavelengths and would boost the fraction of ionized PAH molecules. However, as explained above, the variation of 11.3 μm\/7.7 μm with [Ne iii]\/[Ne ii] is not monotonic. Alternatively, a harder radiation field can modify PAH size distribution through preferential photo erosion of smaller PAH grains (Allain et al. 1996a; Micelotta et al. 2010a, 2010b; Murga et al. 2016). The normally narrow peak size distribution of 150 C atoms for astronomical PAHs (Weingartner & Draine 2001a; Draine & Li 2007) would shift with photo erosion toward sizes of fewer than 100 C atoms (with the total amount of smaller PAHs reduced as well). This effect also can potentially account for the increase of 6.2 μm\/7.7 μm, but it cannot explain why 11.3 μm\/7.7 μm does not simultaneously increase in lockstep. The 11.3 μm\/7.7 μm band ratio first decreases and then increases with [Ne iii]\/[Ne ii]. To account for this peculiar behavior, we propose that, during the photo erosion process, a harder radiation field first elevates the ionization fraction of the PAH molecules up to a certain threshold, which results in the decrease of 11.3 μm\/7.7 μm, beyond which photo erosion proceeds to dominate by modifying the PAH size distribution, which results in the increase of 6.2 μm\/7.7 μm and 11.3 μm\/7.7 μm. In addition, preferential photodestruction of the ionized PAH grains, which are more vulnerable relative to the neutral ones (Allain et al. 1996b; Holm et al. 2011), also may contribute to the increase of 11.3 μm\/7.7 μm. This scenario further provides a plausible explanation for the severe depletion of the overall PAH emission among the dwarf galaxies with the hardest radiation field (Figure 6(a)).","Citation Text":["Allain et al. 1996a"],"Citation Start End":[[746,765]]} {"Identifier":"2022ApJ...939...22ZDraine_et_al._2021_Instance_1","Paragraph":"How does excitation affect 6.2 μm\/7.7 μm? A harder illuminating spectrum contains more UV photons at higher energy and hence directly enhances PAH emission at shorter wavelengths relative to that at longer wavelengths (Draine et al. 2021; Rigopoulou et al. 2021). If this were true, the 11.3 μm\/7.7 μm band ratio should decrease strictly with increasing excitation, because a harder radiation field preferentially enhances PAH emission at shorter wavelengths and would boost the fraction of ionized PAH molecules. However, as explained above, the variation of 11.3 μm\/7.7 μm with [Ne iii]\/[Ne ii] is not monotonic. Alternatively, a harder radiation field can modify PAH size distribution through preferential photo erosion of smaller PAH grains (Allain et al. 1996a; Micelotta et al. 2010a, 2010b; Murga et al. 2016). The normally narrow peak size distribution of 150 C atoms for astronomical PAHs (Weingartner & Draine 2001a; Draine & Li 2007) would shift with photo erosion toward sizes of fewer than 100 C atoms (with the total amount of smaller PAHs reduced as well). This effect also can potentially account for the increase of 6.2 μm\/7.7 μm, but it cannot explain why 11.3 μm\/7.7 μm does not simultaneously increase in lockstep. The 11.3 μm\/7.7 μm band ratio first decreases and then increases with [Ne iii]\/[Ne ii]. To account for this peculiar behavior, we propose that, during the photo erosion process, a harder radiation field first elevates the ionization fraction of the PAH molecules up to a certain threshold, which results in the decrease of 11.3 μm\/7.7 μm, beyond which photo erosion proceeds to dominate by modifying the PAH size distribution, which results in the increase of 6.2 μm\/7.7 μm and 11.3 μm\/7.7 μm. In addition, preferential photodestruction of the ionized PAH grains, which are more vulnerable relative to the neutral ones (Allain et al. 1996b; Holm et al. 2011), also may contribute to the increase of 11.3 μm\/7.7 μm. This scenario further provides a plausible explanation for the severe depletion of the overall PAH emission among the dwarf galaxies with the hardest radiation field (Figure 6(a)).","Citation Text":["Draine et al. 2021"],"Citation Start End":[[219,237]]} {"Identifier":"2022ApJ...939...22ZAllain_et_al._1996b_Instance_1","Paragraph":"How does excitation affect 6.2 μm\/7.7 μm? A harder illuminating spectrum contains more UV photons at higher energy and hence directly enhances PAH emission at shorter wavelengths relative to that at longer wavelengths (Draine et al. 2021; Rigopoulou et al. 2021). If this were true, the 11.3 μm\/7.7 μm band ratio should decrease strictly with increasing excitation, because a harder radiation field preferentially enhances PAH emission at shorter wavelengths and would boost the fraction of ionized PAH molecules. However, as explained above, the variation of 11.3 μm\/7.7 μm with [Ne iii]\/[Ne ii] is not monotonic. Alternatively, a harder radiation field can modify PAH size distribution through preferential photo erosion of smaller PAH grains (Allain et al. 1996a; Micelotta et al. 2010a, 2010b; Murga et al. 2016). The normally narrow peak size distribution of 150 C atoms for astronomical PAHs (Weingartner & Draine 2001a; Draine & Li 2007) would shift with photo erosion toward sizes of fewer than 100 C atoms (with the total amount of smaller PAHs reduced as well). This effect also can potentially account for the increase of 6.2 μm\/7.7 μm, but it cannot explain why 11.3 μm\/7.7 μm does not simultaneously increase in lockstep. The 11.3 μm\/7.7 μm band ratio first decreases and then increases with [Ne iii]\/[Ne ii]. To account for this peculiar behavior, we propose that, during the photo erosion process, a harder radiation field first elevates the ionization fraction of the PAH molecules up to a certain threshold, which results in the decrease of 11.3 μm\/7.7 μm, beyond which photo erosion proceeds to dominate by modifying the PAH size distribution, which results in the increase of 6.2 μm\/7.7 μm and 11.3 μm\/7.7 μm. In addition, preferential photodestruction of the ionized PAH grains, which are more vulnerable relative to the neutral ones (Allain et al. 1996b; Holm et al. 2011), also may contribute to the increase of 11.3 μm\/7.7 μm. This scenario further provides a plausible explanation for the severe depletion of the overall PAH emission among the dwarf galaxies with the hardest radiation field (Figure 6(a)).","Citation Text":["Allain et al. 1996b"],"Citation Start End":[[1855,1874]]} {"Identifier":"2022ApJ...939...22ZDraine_&_Li_2007_Instance_1","Paragraph":"How does excitation affect 6.2 μm\/7.7 μm? A harder illuminating spectrum contains more UV photons at higher energy and hence directly enhances PAH emission at shorter wavelengths relative to that at longer wavelengths (Draine et al. 2021; Rigopoulou et al. 2021). If this were true, the 11.3 μm\/7.7 μm band ratio should decrease strictly with increasing excitation, because a harder radiation field preferentially enhances PAH emission at shorter wavelengths and would boost the fraction of ionized PAH molecules. However, as explained above, the variation of 11.3 μm\/7.7 μm with [Ne iii]\/[Ne ii] is not monotonic. Alternatively, a harder radiation field can modify PAH size distribution through preferential photo erosion of smaller PAH grains (Allain et al. 1996a; Micelotta et al. 2010a, 2010b; Murga et al. 2016). The normally narrow peak size distribution of 150 C atoms for astronomical PAHs (Weingartner & Draine 2001a; Draine & Li 2007) would shift with photo erosion toward sizes of fewer than 100 C atoms (with the total amount of smaller PAHs reduced as well). This effect also can potentially account for the increase of 6.2 μm\/7.7 μm, but it cannot explain why 11.3 μm\/7.7 μm does not simultaneously increase in lockstep. The 11.3 μm\/7.7 μm band ratio first decreases and then increases with [Ne iii]\/[Ne ii]. To account for this peculiar behavior, we propose that, during the photo erosion process, a harder radiation field first elevates the ionization fraction of the PAH molecules up to a certain threshold, which results in the decrease of 11.3 μm\/7.7 μm, beyond which photo erosion proceeds to dominate by modifying the PAH size distribution, which results in the increase of 6.2 μm\/7.7 μm and 11.3 μm\/7.7 μm. In addition, preferential photodestruction of the ionized PAH grains, which are more vulnerable relative to the neutral ones (Allain et al. 1996b; Holm et al. 2011), also may contribute to the increase of 11.3 μm\/7.7 μm. This scenario further provides a plausible explanation for the severe depletion of the overall PAH emission among the dwarf galaxies with the hardest radiation field (Figure 6(a)).","Citation Text":["Draine & Li 2007"],"Citation Start End":[[927,943]]} {"Identifier":"2016ApJ...831....7S__Shen_&_Ho_2014_Instance_1","Paragraph":"It has been known for more than 30 years that quasar emission lines are often shifted from the systemic velocity. Most notable is the average blueshift of the high-ionization broad C iv line (e.g., Gaskell 1982; Wilkes & Carswell 1982; Tytler & Fan 1992; Richards et al. 2002) by hundreds of \n\n\n\n\n\n from systemic, with a strong dependence on luminosity (e.g., Richards et al. 2011). Low-ionization broad lines (such as Mg ii), however, are observed to have an average velocity closer to the systemic velocity (e.g., Hewett & Wild 2010). While high-ionization narrow emission lines such as [O iii] are not as blueshifted as high-ionization broad lines, they can have line peak shifts18\n\n18\n[O iii] often shows a blue asymmetry (e.g., the “blue wing”) that depends on the properties of the quasar (e.g., Heckman et al. 1981; Peterson et al. 1981; Whittle 1985; Veilleux 1991; Zhang et al. 2011; Shen & Ho 2014). The velocity offset of this wing [O iii] component appears to increase with luminosity and Eddington ratio (e.g., Zhang et al. 2011; Shen & Ho 2014), and can reach extreme values of ≳1000 \n\n\n\n\n\n at the highest quasar luminosities (e.g., Shen 2016; Zakamska et al. 2016). However, the velocity offset of the core [O iii] component or the [O iii] peak is generally more stable and lies within ∼50 \n\n\n\n\n\n of the systemic velocity, with only mild dependences on quasar luminosity and Eddington ratio (e.g., Figure 2 and Figure E2 in Shen & Ho 2014, also see, Hewett & Wild 2010).\n of tens of \n\n\n\n\n\n, with some extreme cases exceeding a hundred \n\n\n\n\n\n (e.g., the so-called “blue outliers,” Zamanov et al. 2002; Boroson 2005; Komossa et al. 2008; Marziani et al. 2015). These average trends have been generally confirmed with recent large spectroscopic quasar samples (e.g., Vanden Berk et al. 2001; Richards et al. 2002, 2011; Shen et al. 2007, 2008, 2011; Hewett & Wild 2010; Zhang et al. 2011; Shen & Ho 2014), although differences in measuring the line center and the reference line used for systemic velocity will affect the exact value of the inferred velocity shifts.","Citation Text":["Shen & Ho 2014"],"Citation Start End":[[893,907]]} {"Identifier":"2016ApJ...831....7S__Shen_&_Ho_2014_Instance_2","Paragraph":"It has been known for more than 30 years that quasar emission lines are often shifted from the systemic velocity. Most notable is the average blueshift of the high-ionization broad C iv line (e.g., Gaskell 1982; Wilkes & Carswell 1982; Tytler & Fan 1992; Richards et al. 2002) by hundreds of \n\n\n\n\n\n from systemic, with a strong dependence on luminosity (e.g., Richards et al. 2011). Low-ionization broad lines (such as Mg ii), however, are observed to have an average velocity closer to the systemic velocity (e.g., Hewett & Wild 2010). While high-ionization narrow emission lines such as [O iii] are not as blueshifted as high-ionization broad lines, they can have line peak shifts18\n\n18\n[O iii] often shows a blue asymmetry (e.g., the “blue wing”) that depends on the properties of the quasar (e.g., Heckman et al. 1981; Peterson et al. 1981; Whittle 1985; Veilleux 1991; Zhang et al. 2011; Shen & Ho 2014). The velocity offset of this wing [O iii] component appears to increase with luminosity and Eddington ratio (e.g., Zhang et al. 2011; Shen & Ho 2014), and can reach extreme values of ≳1000 \n\n\n\n\n\n at the highest quasar luminosities (e.g., Shen 2016; Zakamska et al. 2016). However, the velocity offset of the core [O iii] component or the [O iii] peak is generally more stable and lies within ∼50 \n\n\n\n\n\n of the systemic velocity, with only mild dependences on quasar luminosity and Eddington ratio (e.g., Figure 2 and Figure E2 in Shen & Ho 2014, also see, Hewett & Wild 2010).\n of tens of \n\n\n\n\n\n, with some extreme cases exceeding a hundred \n\n\n\n\n\n (e.g., the so-called “blue outliers,” Zamanov et al. 2002; Boroson 2005; Komossa et al. 2008; Marziani et al. 2015). These average trends have been generally confirmed with recent large spectroscopic quasar samples (e.g., Vanden Berk et al. 2001; Richards et al. 2002, 2011; Shen et al. 2007, 2008, 2011; Hewett & Wild 2010; Zhang et al. 2011; Shen & Ho 2014), although differences in measuring the line center and the reference line used for systemic velocity will affect the exact value of the inferred velocity shifts.","Citation Text":["Shen & Ho 2014"],"Citation Start End":[[1043,1057]]} {"Identifier":"2016ApJ...831....7S__Shen_&_Ho_2014_Instance_3","Paragraph":"It has been known for more than 30 years that quasar emission lines are often shifted from the systemic velocity. Most notable is the average blueshift of the high-ionization broad C iv line (e.g., Gaskell 1982; Wilkes & Carswell 1982; Tytler & Fan 1992; Richards et al. 2002) by hundreds of \n\n\n\n\n\n from systemic, with a strong dependence on luminosity (e.g., Richards et al. 2011). Low-ionization broad lines (such as Mg ii), however, are observed to have an average velocity closer to the systemic velocity (e.g., Hewett & Wild 2010). While high-ionization narrow emission lines such as [O iii] are not as blueshifted as high-ionization broad lines, they can have line peak shifts18\n\n18\n[O iii] often shows a blue asymmetry (e.g., the “blue wing”) that depends on the properties of the quasar (e.g., Heckman et al. 1981; Peterson et al. 1981; Whittle 1985; Veilleux 1991; Zhang et al. 2011; Shen & Ho 2014). The velocity offset of this wing [O iii] component appears to increase with luminosity and Eddington ratio (e.g., Zhang et al. 2011; Shen & Ho 2014), and can reach extreme values of ≳1000 \n\n\n\n\n\n at the highest quasar luminosities (e.g., Shen 2016; Zakamska et al. 2016). However, the velocity offset of the core [O iii] component or the [O iii] peak is generally more stable and lies within ∼50 \n\n\n\n\n\n of the systemic velocity, with only mild dependences on quasar luminosity and Eddington ratio (e.g., Figure 2 and Figure E2 in Shen & Ho 2014, also see, Hewett & Wild 2010).\n of tens of \n\n\n\n\n\n, with some extreme cases exceeding a hundred \n\n\n\n\n\n (e.g., the so-called “blue outliers,” Zamanov et al. 2002; Boroson 2005; Komossa et al. 2008; Marziani et al. 2015). These average trends have been generally confirmed with recent large spectroscopic quasar samples (e.g., Vanden Berk et al. 2001; Richards et al. 2002, 2011; Shen et al. 2007, 2008, 2011; Hewett & Wild 2010; Zhang et al. 2011; Shen & Ho 2014), although differences in measuring the line center and the reference line used for systemic velocity will affect the exact value of the inferred velocity shifts.","Citation Text":["Shen & Ho 2014"],"Citation Start End":[[1439,1453]]} {"Identifier":"2016ApJ...831....7S__Shen_&_Ho_2014_Instance_4","Paragraph":"It has been known for more than 30 years that quasar emission lines are often shifted from the systemic velocity. Most notable is the average blueshift of the high-ionization broad C iv line (e.g., Gaskell 1982; Wilkes & Carswell 1982; Tytler & Fan 1992; Richards et al. 2002) by hundreds of \n\n\n\n\n\n from systemic, with a strong dependence on luminosity (e.g., Richards et al. 2011). Low-ionization broad lines (such as Mg ii), however, are observed to have an average velocity closer to the systemic velocity (e.g., Hewett & Wild 2010). While high-ionization narrow emission lines such as [O iii] are not as blueshifted as high-ionization broad lines, they can have line peak shifts18\n\n18\n[O iii] often shows a blue asymmetry (e.g., the “blue wing”) that depends on the properties of the quasar (e.g., Heckman et al. 1981; Peterson et al. 1981; Whittle 1985; Veilleux 1991; Zhang et al. 2011; Shen & Ho 2014). The velocity offset of this wing [O iii] component appears to increase with luminosity and Eddington ratio (e.g., Zhang et al. 2011; Shen & Ho 2014), and can reach extreme values of ≳1000 \n\n\n\n\n\n at the highest quasar luminosities (e.g., Shen 2016; Zakamska et al. 2016). However, the velocity offset of the core [O iii] component or the [O iii] peak is generally more stable and lies within ∼50 \n\n\n\n\n\n of the systemic velocity, with only mild dependences on quasar luminosity and Eddington ratio (e.g., Figure 2 and Figure E2 in Shen & Ho 2014, also see, Hewett & Wild 2010).\n of tens of \n\n\n\n\n\n, with some extreme cases exceeding a hundred \n\n\n\n\n\n (e.g., the so-called “blue outliers,” Zamanov et al. 2002; Boroson 2005; Komossa et al. 2008; Marziani et al. 2015). These average trends have been generally confirmed with recent large spectroscopic quasar samples (e.g., Vanden Berk et al. 2001; Richards et al. 2002, 2011; Shen et al. 2007, 2008, 2011; Hewett & Wild 2010; Zhang et al. 2011; Shen & Ho 2014), although differences in measuring the line center and the reference line used for systemic velocity will affect the exact value of the inferred velocity shifts.","Citation Text":["Shen & Ho 2014"],"Citation Start End":[[1902,1916]]} {"Identifier":"2018ApJ...869...23Z__Hunana_&_Zank_2010_Instance_1","Paragraph":"To evaluate the turbulence heating term St, we need to describe the transport and dissipation of turbulence throughout the heliosphere, ensuring that the appropriate sources of turbulence are identified as well as that associated with pickup ion creation in the distant solar wind. The turbulence transport model we use is that of Zank et al. (2017). The current paradigm for fully developed turbulence in the solar wind is that it is a superposition of a majority quasi-2D component and a minority slab component, e.g., Matthaeus et al. (1995). The nearly incompressible (NI) reduction of MHD in the plasma beta \n\n\n\n\n\n regime, appropriate to most of the solar wind, shows that such a decomposition (quasi-2D plus slab) arises naturally in the presence of a sufficiently strong guide magnetic field (Zank & Matthaeus 1992, 1993; Hunana & Zank 2010). The stationary form of the NI MHD transport equations describing the evolution of the majority quasi-2D component in a spherically symmetric solar wind with an azimuthal magnetic field can be expressed as (Adhikari et al. 2017; Zank et al. 2017)\n22\n\n\n\n\n\n\n\n23\n\n\n\n\n\n\n\n24\n\n\n\n\n\n\n\n25\n\n\n\n\n\nHere, \n\n\n\n\n\n are the forward and backward Elsässer variables, combining the quasi-2D fluctuating velocity field \n\n\n\n\n\n and the fluctuating magnetic field \n\n\n\n\n\n through the fluctuating (turbulent) Alfvén velocity \n\n\n\n\n\n. The variance of the fluctuating Elsässer variables is denoted by \n\n\n\n\n\n, where the operator \n\n\n\n\n\n averages over small scales and high frequencies. The quasi-2D residual energy (or energy difference) is defined by \n\n\n\n\n\n. The total fluctuating quasi-2D energy is denoted by \n\n\n\n\n\n, and the quasi-2D correlation lengths \n\n\n\n\n\n are related to the correlation functions \n\n\n\n\n\n through \n\n\n\n\n\n. Finally, \n\n\n\n\n\n is a correlation function related to the residual energy. The energy for the forward and backward slab Elsässer variables \n\n\n\n\n\n and the slab correlation length \n\n\n\n\n\n are discussed further below. However, we note that the quasi-2D and slab components are coupled, capturing the 3-mode coupling (Shebalin et al. 1983; Zank et al. 2017) that governs spectral transfer in the inertial range. This is expressed by the source-like terms in Equations (22) and (23) that contain the slab variables. Equations (22) and (23) contain genuine source terms associated with stream shear (Adhikari et al. 2017; Zank et al. 2017), where \n\n\n\n\n\n denotes the strength of the stream-shear source of forward or backward quasi-2D fluctuations, \n\n\n\n\n\n the characteristic velocity jump across the stream, and VA the large-scale Alfvén speed. A lengthy derivation and discussion of these equations can be found in Zank et al. (2017) and specific solutions appropriate to a prescribed large-scale solar wind can be found in Adhikari et al. (2017).","Citation Text":["Hunana & Zank 2010"],"Citation Start End":[[829,847]]} {"Identifier":"2022AandA...659A..81B__Immer_et_al._(2019)_Instance_1","Paragraph":"To characterize the motions of the deeply embedded gas that could reveal signatures of rotation and infall and that would help us to understand the formation of massive stars, for many years we have been carrying out multiple high angular resolution studies of hot molecular cores (HMCs), first with the IRAM Plateau de Bure (PdB) and Submillimeter Array (SMA) interferometers (Beltrán et al. 2004, 2005, 2011a,b), and later on with the Atacama Large Millimeter\/submillimeter Array (ALMA, Cesaroni et al. 2017; Beltrán et al. 2018, 2021; Moscadelli et al. 2018, 2021; Goddi et al. 2020) and the IRAM NOrthern Extended Millimeter Array (NOEMA, Gieser et al. 2019, 2021). Cesaroni et al. (2017) carried out an extensive and systematic search for circumstellar disks around O-type stars by observing a sample of HMCs at 1.4 mm and 0.′′2 resolution with ALMA. One of the HMCs of the sample is G31.41+0.31 (hereafter G31), which is located at 3.75 kpc Immer et al. (2019), has a luminosity of ~ 5 × 104 L⊙ Osorio et al. (2009), and displays a clear NE–SW velocity gradient suggestive of rotation (e.g., Beltrán et al. 2004). Among the HMCs studied, G31 stands out as the only source that displays accelerating infall and rotational spin-up (Beltrán et al. 2018). This characteristic suggests that the source is in an earlier evolutionary stage compared to all other targets in the Cesaroni et al. sample. At an angular resolution of 0.′′2 (~ 750 au), the dust continuum emission traces a well-resolved, monolithic, and featureless core, called Main by Beltrán et al. (2018), with no hint of fragmentation despite the high mass (~ 70 M⊙; Cesaroni et al. 2019) and the diameter of ~8000 au. However, new ALMA observations at 1.4 and 3.5 mm at a higher angular resolution of ~ 0.′′1 (~ 375 au), and Very Large Array (VLA) observations at 7 mm and ~ 0.′′05 (~ 190 au) resolution have resolved for the first time the HMC into a small protocluster composed of at least four massive sources, named A, B, C, and D and with masses ranging from ~15 to ~ 26 M⊙, within the central 1″ (~ 3750 au) region of the core (Beltrán et al. 2021). These observations have revealed that the homogeneous appearance previously observed at 1.4 mm and 0.′′2 is a consequence of both high dust opacity and insufficient angular resolution. Besides the four sources embedded in the Main core, there are six additional millimeter sources located very close to the core which appear to outline streams or filaments of matter pointing to the HMC (Beltrán et al. 2021).","Citation Text":["Immer et al. (2019)"],"Citation Start End":[[947,966]]} {"Identifier":"2022AandA...659A..8Beltrán_et_al._2018_Instance_1","Paragraph":"To characterize the motions of the deeply embedded gas that could reveal signatures of rotation and infall and that would help us to understand the formation of massive stars, for many years we have been carrying out multiple high angular resolution studies of hot molecular cores (HMCs), first with the IRAM Plateau de Bure (PdB) and Submillimeter Array (SMA) interferometers (Beltrán et al. 2004, 2005, 2011a,b), and later on with the Atacama Large Millimeter\/submillimeter Array (ALMA, Cesaroni et al. 2017; Beltrán et al. 2018, 2021; Moscadelli et al. 2018, 2021; Goddi et al. 2020) and the IRAM NOrthern Extended Millimeter Array (NOEMA, Gieser et al. 2019, 2021). Cesaroni et al. (2017) carried out an extensive and systematic search for circumstellar disks around O-type stars by observing a sample of HMCs at 1.4 mm and 0.′′2 resolution with ALMA. One of the HMCs of the sample is G31.41+0.31 (hereafter G31), which is located at 3.75 kpc Immer et al. (2019), has a luminosity of ~ 5 × 104 L⊙ Osorio et al. (2009), and displays a clear NE–SW velocity gradient suggestive of rotation (e.g., Beltrán et al. 2004). Among the HMCs studied, G31 stands out as the only source that displays accelerating infall and rotational spin-up (Beltrán et al. 2018). This characteristic suggests that the source is in an earlier evolutionary stage compared to all other targets in the Cesaroni et al. sample. At an angular resolution of 0.′′2 (~ 750 au), the dust continuum emission traces a well-resolved, monolithic, and featureless core, called Main by Beltrán et al. (2018), with no hint of fragmentation despite the high mass (~ 70 M⊙; Cesaroni et al. 2019) and the diameter of ~8000 au. However, new ALMA observations at 1.4 and 3.5 mm at a higher angular resolution of ~ 0.′′1 (~ 375 au), and Very Large Array (VLA) observations at 7 mm and ~ 0.′′05 (~ 190 au) resolution have resolved for the first time the HMC into a small protocluster composed of at least four massive sources, named A, B, C, and D and with masses ranging from ~15 to ~ 26 M⊙, within the central 1″ (~ 3750 au) region of the core (Beltrán et al. 2021). These observations have revealed that the homogeneous appearance previously observed at 1.4 mm and 0.′′2 is a consequence of both high dust opacity and insufficient angular resolution. Besides the four sources embedded in the Main core, there are six additional millimeter sources located very close to the core which appear to outline streams or filaments of matter pointing to the HMC (Beltrán et al. 2021).","Citation Text":["Beltrán et al. 2018"],"Citation Start End":[[511,530]]} {"Identifier":"2022AandA...659A..8Beltrán_et_al._2018_Instance_2","Paragraph":"To characterize the motions of the deeply embedded gas that could reveal signatures of rotation and infall and that would help us to understand the formation of massive stars, for many years we have been carrying out multiple high angular resolution studies of hot molecular cores (HMCs), first with the IRAM Plateau de Bure (PdB) and Submillimeter Array (SMA) interferometers (Beltrán et al. 2004, 2005, 2011a,b), and later on with the Atacama Large Millimeter\/submillimeter Array (ALMA, Cesaroni et al. 2017; Beltrán et al. 2018, 2021; Moscadelli et al. 2018, 2021; Goddi et al. 2020) and the IRAM NOrthern Extended Millimeter Array (NOEMA, Gieser et al. 2019, 2021). Cesaroni et al. (2017) carried out an extensive and systematic search for circumstellar disks around O-type stars by observing a sample of HMCs at 1.4 mm and 0.′′2 resolution with ALMA. One of the HMCs of the sample is G31.41+0.31 (hereafter G31), which is located at 3.75 kpc Immer et al. (2019), has a luminosity of ~ 5 × 104 L⊙ Osorio et al. (2009), and displays a clear NE–SW velocity gradient suggestive of rotation (e.g., Beltrán et al. 2004). Among the HMCs studied, G31 stands out as the only source that displays accelerating infall and rotational spin-up (Beltrán et al. 2018). This characteristic suggests that the source is in an earlier evolutionary stage compared to all other targets in the Cesaroni et al. sample. At an angular resolution of 0.′′2 (~ 750 au), the dust continuum emission traces a well-resolved, monolithic, and featureless core, called Main by Beltrán et al. (2018), with no hint of fragmentation despite the high mass (~ 70 M⊙; Cesaroni et al. 2019) and the diameter of ~8000 au. However, new ALMA observations at 1.4 and 3.5 mm at a higher angular resolution of ~ 0.′′1 (~ 375 au), and Very Large Array (VLA) observations at 7 mm and ~ 0.′′05 (~ 190 au) resolution have resolved for the first time the HMC into a small protocluster composed of at least four massive sources, named A, B, C, and D and with masses ranging from ~15 to ~ 26 M⊙, within the central 1″ (~ 3750 au) region of the core (Beltrán et al. 2021). These observations have revealed that the homogeneous appearance previously observed at 1.4 mm and 0.′′2 is a consequence of both high dust opacity and insufficient angular resolution. Besides the four sources embedded in the Main core, there are six additional millimeter sources located very close to the core which appear to outline streams or filaments of matter pointing to the HMC (Beltrán et al. 2021).","Citation Text":["Beltrán et al. 2018"],"Citation Start End":[[1236,1255]]} {"Identifier":"2022AandA...659A..8Beltrán_et_al._(2018)_Instance_3","Paragraph":"To characterize the motions of the deeply embedded gas that could reveal signatures of rotation and infall and that would help us to understand the formation of massive stars, for many years we have been carrying out multiple high angular resolution studies of hot molecular cores (HMCs), first with the IRAM Plateau de Bure (PdB) and Submillimeter Array (SMA) interferometers (Beltrán et al. 2004, 2005, 2011a,b), and later on with the Atacama Large Millimeter\/submillimeter Array (ALMA, Cesaroni et al. 2017; Beltrán et al. 2018, 2021; Moscadelli et al. 2018, 2021; Goddi et al. 2020) and the IRAM NOrthern Extended Millimeter Array (NOEMA, Gieser et al. 2019, 2021). Cesaroni et al. (2017) carried out an extensive and systematic search for circumstellar disks around O-type stars by observing a sample of HMCs at 1.4 mm and 0.′′2 resolution with ALMA. One of the HMCs of the sample is G31.41+0.31 (hereafter G31), which is located at 3.75 kpc Immer et al. (2019), has a luminosity of ~ 5 × 104 L⊙ Osorio et al. (2009), and displays a clear NE–SW velocity gradient suggestive of rotation (e.g., Beltrán et al. 2004). Among the HMCs studied, G31 stands out as the only source that displays accelerating infall and rotational spin-up (Beltrán et al. 2018). This characteristic suggests that the source is in an earlier evolutionary stage compared to all other targets in the Cesaroni et al. sample. At an angular resolution of 0.′′2 (~ 750 au), the dust continuum emission traces a well-resolved, monolithic, and featureless core, called Main by Beltrán et al. (2018), with no hint of fragmentation despite the high mass (~ 70 M⊙; Cesaroni et al. 2019) and the diameter of ~8000 au. However, new ALMA observations at 1.4 and 3.5 mm at a higher angular resolution of ~ 0.′′1 (~ 375 au), and Very Large Array (VLA) observations at 7 mm and ~ 0.′′05 (~ 190 au) resolution have resolved for the first time the HMC into a small protocluster composed of at least four massive sources, named A, B, C, and D and with masses ranging from ~15 to ~ 26 M⊙, within the central 1″ (~ 3750 au) region of the core (Beltrán et al. 2021). These observations have revealed that the homogeneous appearance previously observed at 1.4 mm and 0.′′2 is a consequence of both high dust opacity and insufficient angular resolution. Besides the four sources embedded in the Main core, there are six additional millimeter sources located very close to the core which appear to outline streams or filaments of matter pointing to the HMC (Beltrán et al. 2021).","Citation Text":["Beltrán et al. (2018)"],"Citation Start End":[[1547,1568]]} {"Identifier":"2016AandA...590A.101B__Lambrechts_&_Johansen_2012_Instance_1","Paragraph":"The efficiency of pebble accretion is determined by the pebble scale height in the disc given by (5)\\begin{equation} \\label{eq:Hpebble} H_{\\rm peb} = H\\sqrt{\\alpha\/\\tau_{\\rm f}} , \\end{equation}Hpeb=Hα\/τf,where τf is the Stokes number of the particles. If the planetary seed’s Hill radius is larger than the pebble scale height, the planetary seed can accrete efficiently in a 2D manner (6)\\begin{equation} \\label{eq:Mdotpebble} \\dot{M}_{\\rm c, 2D} = 2 \\left(\\frac{\\tau_{\\rm f}}{0.1}\\right)^{2\/3} r_{\\rm H} v_{\\rm H} \\Sigma_{\\rm peb} , \\end{equation}Ṁc,2D=2τf0.12\/3rHvHΣpeb,where rH = r [Mc\/ (3M⋆)] 1\/3 is the Hill radius, vH = ΩKrH the Hill speed, and Σpeb the pebble surface density. For Stokes numbers larger than 0.1, the (τf\/ 0.1)2\/3 term vanishes in Eq. (6), because the planetary seed cannot accrete particles from outside its Hill radius (Lambrechts & Johansen 2012). However for small planetary seeds, the Hill sphere can be smaller than the pebble scale height, so that the seed accretes in a slow 3D fashion (7)\\begin{equation} \\dot{M}_{\\rm c, 3D} = \\dot{M}_{\\rm c, 2D} \\left( \\frac{\\pi (\\tau_{\\rm f}\/0.1)^{1\/3} r_{\\rm H}}{2 \\sqrt{2 \\pi} H_{\\rm peb}} \\right) \\cdot \\end{equation}Ṁc,3D=Ṁc,2Dπ(τf\/0.1)1\/3rH22πHpeb·The transition from 3D to 2D pebble accretion is then reached (Morbidelli et al. 2015) when (8)\\begin{equation} \\label{eq:2D3D} \\frac{\\pi (\\tau_{\\rm f}\/0.1)^{1\/3} r_{\\rm H}}{2 \\sqrt{2 \\pi}} > H_{\\rm peb} . \\end{equation}π(τf\/0.1)1\/3rH22π>Hpeb.Clearly this transition depends on the scale height of the pebbles and thus on the scale height of the gas. Therefore, pebble accretion is slower in the initial planetary growth phase in the outer parts of the disc, because the aspect ratio is larger there. The core can then finally reach its pebble isolation mass (Lambrechts et al. 2014) (9)\\begin{equation} \\label{eq:Misolation} M_{\\rm iso} \\sim 20 \\left( \\frac{H\/r}{0.05}\\right)^3~{M}_{\\rm Earth} , \\end{equation}Miso~20H\/r0.053MEarth,where pebble accretion is terminated and the contraction of the gaseous envelope can start. We use for the contraction of the gaseous envelope the semi-analytical model described by Piso & Youdin (2014), where the contraction phase becomes shorter for more massive planetary cores. This contraction phase additionally depends on the opacity inside the of the planetary envelope, as this determines the cooling and with this the contraction rate of the envelope. Our nominal opacity in the envelope corresponds to similar values as in Movshovitz & Podolak (2008). We discuss the influence of a slower contraction rate in Appendix B. As soon as Menv = Mcore, rapid gas accretion can start. ","Citation Text":["Lambrechts & Johansen 2012"],"Citation Start End":[[850,876]]} {"Identifier":"2022ApJ...929....2L__Myers_et_al._2015_Instance_1","Paragraph":"Solar flares and coronal mass ejections (CMEs) are the most energetic phenomena in the solar coronae, which are considered as different manifestations of the same physical process (Zhang et al. 2001; Priest & Forbes 2002; Zhang et al. 2004; Shibata & Magara 2011). However, flares that are associated with no CMEs are known as “confined flares” or “failed eruptions” (e.g., Ji et al. 2003; Liu et al. 2014; Zhou et al. 2019; Mrozek et al. 2020). Whether an eruption is successful or not is heavily dependent on the strapping force exerted by the overlying magnetic field on the eruptive structure (e.g., Török & Kliem 2005; Guo et al. 2010; Cheng et al. 2011; Zuccarello et al. 2014; Myers et al. 2015; Sun et al. 2015; Amari et al. 2018), which is often a magnetic flux rope (MFR; Vourlidas et al. 2013; Liu 2020). A flux rope undergoes the torus instability (Bateman 1978; Kliem & Török 2006), when the magnitude of the overlying field decreases with height at a sufficiently steep rate, quantified by the decay index \n\n\n\nn=−dlnB\/dlnh\n\n (Bateman 1978), exceeding about 1.5; the corresponding height is referred to as the critical height. Nevertheless, one should bear in mind that the theoretical critical value of n\ncr = 1.5 adopted in many studies, as well as in this study, is derived from a thin, toroidal current ring (Bateman 1978; Kliem & Török 2006). In practice, n\ncr typically scatters around in a range as large as [0.8, 2] for different theoretical considerations (e.g., Démoulin & Aulanier 2010; Olmedo & Zhang 2010), observational studies (e.g., Jing et al. 2018; Duan et al. 2019), numerical simulations (e.g., Fan & Gibson 2007; Török & Kliem 2007), and laboratory experiments (e.g., Myers et al. 2015; Alt et al. 2021). Obviously, n\ncr is a function of the flux-rope parameters including the geometry and internal current profile, yet the discrepancy in different studies is also affected by where the decay index is computed (Zuccarello et al. 2016; Alt et al. 2021).","Citation Text":["Myers et al. 2015","Myers et al. 2015"],"Citation Start End":[[684,701],[1702,1719]]} {"Identifier":"2021ApJ...912L..19P__Heyer_et_al._2016_Instance_1","Paragraph":"A natural experiment for deciding between these possibilities is to search for a KS relation within individual molecular clouds using counts of the recently formed stars or protostars identified by their bright infrared emission from circumstellar dust. The rarity of massive stars and their disruptive effect on their host cloud means they are poor tracers on cloud scales. Protostars, by contrast, have the advantage that they sample a much shorter time interval and therefore provide a much better estimate of the “instantaneous” star formation rate (SFR), and they allow measurements of the SFR even in clouds that lack massive stars and have not been significantly affected by feedback. Studies based on this method generally do find a reasonable correlation between the number of young stellar objects (YSOs) in a cloud and its gas mass above a certain density, or its gas mass divided by its mean-density freefall time (Krumholz et al. 2012a, 2019; Lada et al. 2012; Heyer et al. 2016). Within molecular clouds, several studies have found a power-law correlation between the surface densities of YSOs and gas (Gutermuth et al. 2011; Lada et al. 2013; Willis et al. 2015). Most recently, Pokhrel et al. (2020) used high-accuracy YSO catalogs and high dynamic range gas column densities to show the presence of these laws in 12 nearby clouds. This correlation is consistent with a star formation surface density being proportional to the gas surface density squared. The scaling of this law, however, varies significantly between clouds. Moreover, their analysis technique examines the density of gas around stars on a star-by-star basis, and therefore cannot easily determine whether there is a KS relation based on the volume density of gas. Using the same data, we apply a different approach to determine the star formation law that includes a dependence on the volume density of the gas. We find that the star formation law can be recast as an effectively universal linear dependence of the surface densities between star formation rate and gas mass per freefall time, with much less scatter between clouds.","Citation Text":["Heyer et al. 2016"],"Citation Start End":[[974,991]]} {"Identifier":"2021ApJ...912L..19PGutermuth_et_al._2011_Instance_1","Paragraph":"A natural experiment for deciding between these possibilities is to search for a KS relation within individual molecular clouds using counts of the recently formed stars or protostars identified by their bright infrared emission from circumstellar dust. The rarity of massive stars and their disruptive effect on their host cloud means they are poor tracers on cloud scales. Protostars, by contrast, have the advantage that they sample a much shorter time interval and therefore provide a much better estimate of the “instantaneous” star formation rate (SFR), and they allow measurements of the SFR even in clouds that lack massive stars and have not been significantly affected by feedback. Studies based on this method generally do find a reasonable correlation between the number of young stellar objects (YSOs) in a cloud and its gas mass above a certain density, or its gas mass divided by its mean-density freefall time (Krumholz et al. 2012a, 2019; Lada et al. 2012; Heyer et al. 2016). Within molecular clouds, several studies have found a power-law correlation between the surface densities of YSOs and gas (Gutermuth et al. 2011; Lada et al. 2013; Willis et al. 2015). Most recently, Pokhrel et al. (2020) used high-accuracy YSO catalogs and high dynamic range gas column densities to show the presence of these laws in 12 nearby clouds. This correlation is consistent with a star formation surface density being proportional to the gas surface density squared. The scaling of this law, however, varies significantly between clouds. Moreover, their analysis technique examines the density of gas around stars on a star-by-star basis, and therefore cannot easily determine whether there is a KS relation based on the volume density of gas. Using the same data, we apply a different approach to determine the star formation law that includes a dependence on the volume density of the gas. We find that the star formation law can be recast as an effectively universal linear dependence of the surface densities between star formation rate and gas mass per freefall time, with much less scatter between clouds.","Citation Text":["Gutermuth et al. 2011"],"Citation Start End":[[1117,1138]]} {"Identifier":"2021ApJ...912L..19PPokhrel_et_al._(2020)_Instance_1","Paragraph":"A natural experiment for deciding between these possibilities is to search for a KS relation within individual molecular clouds using counts of the recently formed stars or protostars identified by their bright infrared emission from circumstellar dust. The rarity of massive stars and their disruptive effect on their host cloud means they are poor tracers on cloud scales. Protostars, by contrast, have the advantage that they sample a much shorter time interval and therefore provide a much better estimate of the “instantaneous” star formation rate (SFR), and they allow measurements of the SFR even in clouds that lack massive stars and have not been significantly affected by feedback. Studies based on this method generally do find a reasonable correlation between the number of young stellar objects (YSOs) in a cloud and its gas mass above a certain density, or its gas mass divided by its mean-density freefall time (Krumholz et al. 2012a, 2019; Lada et al. 2012; Heyer et al. 2016). Within molecular clouds, several studies have found a power-law correlation between the surface densities of YSOs and gas (Gutermuth et al. 2011; Lada et al. 2013; Willis et al. 2015). Most recently, Pokhrel et al. (2020) used high-accuracy YSO catalogs and high dynamic range gas column densities to show the presence of these laws in 12 nearby clouds. This correlation is consistent with a star formation surface density being proportional to the gas surface density squared. The scaling of this law, however, varies significantly between clouds. Moreover, their analysis technique examines the density of gas around stars on a star-by-star basis, and therefore cannot easily determine whether there is a KS relation based on the volume density of gas. Using the same data, we apply a different approach to determine the star formation law that includes a dependence on the volume density of the gas. We find that the star formation law can be recast as an effectively universal linear dependence of the surface densities between star formation rate and gas mass per freefall time, with much less scatter between clouds.","Citation Text":["Pokhrel et al. (2020)"],"Citation Start End":[[1194,1215]]} {"Identifier":"2021ApJ...917...19Z__Yuan_et_al._2012a_Instance_1","Paragraph":"In the above equations, ρ is the mass density, v is the velocity, ψ(= −GM\/r) is the Newtonian potential (where r is the distance from the central black hole, M is the black hole mass, and G is the gravitational constant), pgas is the gas pressure, σ is the viscous stress tensor, e is the gas internal energy, and Fc is the thermal conduction. Here, d\/dt ≡ ∂\/∂t + v · ∇ represents the Lagrangian or comoving derivative. The equation of state of the ideal gas is considered as \n\n\n\n\n\n\np\n\n\ngas\n\n\n=\n\n\nγ\n−\n1\n\n\nρ\ne\n\n\n, with γ = 5\/3 being the adiabatic index. In the purely HD limit, like our case, Fc is defined as\n4\n\n\n\n\n\n\nF\n\n\nc\n\n\n=\n−\nλ\n∇\nT\n,\n\n\nwhere λ is the thermal diffusivity and T is the gas temperature. We use spherical coordinates (r, θ, ϕ) to solve the above set of equations. In most previous semianalytical studies on hot accretion flow, they assumed that the system is in a steady state and axisymmetric, i.e., ∂\/∂ϕ = ∂\/∂t = 0. These assumptions imply that all physical quantities are independent of the azimuthal angle, ϕ, and the time, t. Following numerical simulations of hot accretion flow (e.g., Stone et al. 1999; Yuan et al. 2012a), we consider the following components of the viscous stress tensor:\n5\n\n\n\n\n\n\nσ\n\n\nr\nθ\n\n\n=\nρ\nν\n\n\nr\n\n\n\n∂\n\n\n∂\nr\n\n\n\n\n\n\n\n\n\n\nv\n\n\nθ\n\n\n\n\nr\n\n\n\n\n\n+\n\n\n\n1\n\n\nr\n\n\n\n\n\n\n∂\n\n\nv\n\n\nr\n\n\n\n\n∂\nθ\n\n\n\n\n\n,\n\n\n\n\n6\n\n\n\n\n\n\nσ\n\n\nr\nϕ\n\n\n=\nρ\nν\n\n\nr\n\n\n\n∂\n\n\n∂\nr\n\n\n\n\n\n\n\n\n\n\nv\n\n\nϕ\n\n\n\n\nr\n\n\n\n\n\n\n\n,\n\n\n\n\n7\n\n\n\n\n\n\nσ\n\n\nθ\nϕ\n\n\n=\nρ\nν\n\n\n\n\n\nsin\nθ\n\n\nr\n\n\n\n\n\n\n∂\n\n\n∂\nθ\n\n\n\n\n\n\n\n\n\n\nv\n\n\nϕ\n\n\n\n\nsin\nθ\n\n\n\n\n\n\n\n,\n\n\nwhere ν is called the kinematic viscosity coefficient. By substituting all the above assumptions and definitions into Equations (1)–(3), we obtain following partial differential equations (PDEs) in spherical coordinates. Hence, the continuity equation is reduced to the following form\n8\n\n\n\n\n\n\n\n1\n\n\n\n\nr\n\n\n2\n\n\n\n\n\n\n\n\n∂\n\n\n∂\nr\n\n\n\n\n\n\n\nr\n\n\n2\n\n\nρ\n\n\nv\n\n\nr\n\n\n\n\n+\n\n\n\n1\n\n\nr\nsin\nθ\n\n\n\n\n\n\n∂\n\n\n∂\nθ\n\n\n\n\n\nρ\n\n\nv\n\n\nθ\n\n\nsin\nθ\n\n\n=\n0\n.\n\n\nThe three components of the momentum equation are as follows:\n9\n\n\n\n\n\n\n\nρ\n\n\n\n\nv\n\n\nr\n\n\n\n\n\n∂\n\n\nv\n\n\nr\n\n\n\n\n∂\nr\n\n\n\n+\n\n\n\n\n\nv\n\n\nθ\n\n\n\n\nr\n\n\n\n\n\n\n\n\n∂\n\n\nv\n\n\nr\n\n\n\n\n∂\nθ\n\n\n\n−\n\n\nv\n\n\nθ\n\n\n\n\n−\n\n\n\n\n\nv\n\n\nϕ\n\n\n2\n\n\n\n\nr\n\n\n\n\n\n\n\n\n\n\n=\n\n−\n\n\n\nGM\nρ\n\n\n\n\nr\n\n\n2\n\n\n\n\n\n−\n\n\n\n∂\n\n\np\n\n\ngas\n\n\n\n\n∂\nr\n\n\n\n+\n\n\n\n1\n\n\nr\nsin\nθ\n\n\n\n\n\n\n∂\n\n\n∂\nθ\n\n\n\n\n\nsin\nθ\n\n\nσ\n\n\nr\nθ\n\n\n\n\n,\n\n\n\n\n\n\n\n10\n\n\n\n\n\n\n\nρ\n\n\n\n\nv\n\n\nr\n\n\n\n\n\n∂\n\n\nv\n\n\nθ\n\n\n\n\n∂\nr\n\n\n\n+\n\n\n\n\n\nv\n\n\nθ\n\n\n\n\nr\n\n\n\n\n\n\n\n\n∂\n\n\nv\n\n\nθ\n\n\n\n\n∂\nθ\n\n\n\n+\n\n\nv\n\n\nr\n\n\n\n\n−\n\n\n\n\n\nv\n\n\nϕ\n\n\n2\n\n\n\n\nr\n\n\n\ncot\nθ\n\n\n\n\n\n\n\n=\n\n−\n\n\n\n1\n\n\nr\n\n\n\n\n\n\n∂\n\n\np\n\n\ngas\n\n\n\n\n∂\nθ\n\n\n\n+\n\n\n\n1\n\n\n\n\nr\n\n\n3\n\n\n\n\n\n\n\n\n∂\n\n\n∂\nr\n\n\n\n\n\n\n\nr\n\n\n3\n\n\n\n\nσ\n\n\nr\nθ\n\n\n\n\n,\n\n\n\n\n\n\n\n11\n\n\n\n\n\n\n\nρ\n\n\n\n\nv\n\n\nr\n\n\n\n\n\n∂\n\n\nv\n\n\nϕ\n\n\n\n\n∂\nr\n\n\n\n+\n\n\n\n\n\nv\n\n\nθ\n\n\n\n\nr\n\n\n\n\n\n\n∂\n\n\nv\n\n\nϕ\n\n\n\n\n∂\nθ\n\n\n\n+\n\n\n\n\n\nv\n\n\nϕ\n\n\n\n\nr\n\n\n\n\n\n\n\nv\n\n\nr\n\n\n+\n\n\nv\n\n\nθ\n\n\ncot\nθ\n\n\n\n\n\n\n\n\n\n=\n\n\n\n\n1\n\n\n\n\nr\n\n\n2\n\n\n\n\n\n\n\n\n∂\n\n\n∂\nr\n\n\n\n\n\n\n\nr\n\n\n2\n\n\n\n\nσ\n\n\nr\nϕ\n\n\n\n\n+\n\n\n\n1\n\n\nr\nsin\nθ\n\n\n\n\n\n\n∂\n\n\n∂\nθ\n\n\n\n\n\nsin\nθ\n\n\nσ\n\n\nθ\nϕ\n\n\n\n\n\n\n\n\n\n+\n\n\n\n\n1\n\n\nr\n\n\n\n\n\n\n\nσ\n\n\nr\nϕ\n\n\n+\n\n\nσ\n\n\nθ\nϕ\n\n\ncot\nθ\n\n\n.\n\n\n\n\n\nThe energy equation is written as\n12\n\n\n\n\n\n\n\nρ\n\n\n\n\nv\n\n\nr\n\n\n\n\n\n∂\ne\n\n\n∂\nr\n\n\n\n+\n\n\n\n\n\nv\n\n\nθ\n\n\n\n\nr\n\n\n\n\n\n\n∂\ne\n\n\n∂\nθ\n\n\n\n\n\n−\n\n\n\n\n\np\n\n\ngas\n\n\n\n\nρ\n\n\n\n\n\n\n\nv\n\n\nr\n\n\n\n\n\n∂\nρ\n\n\n∂\nr\n\n\n\n+\n\n\n\n\n\nv\n\n\nθ\n\n\n\n\nr\n\n\n\n\n\n\n∂\nρ\n\n\n∂\nθ\n\n\n\n\n\n\n\n\n\n\n=\n\n\n\n\n∂\n\n\nv\n\n\nθ\n\n\n\n\n∂\nr\n\n\n\n\n\nσ\n\n\nr\nθ\n\n\n+\n\n\n\n∂\n\n\nv\n\n\nϕ\n\n\n\n\n∂\nr\n\n\n\n\n\nσ\n\n\nr\nϕ\n\n\n+\n\n\n\n1\n\n\nr\n\n\n\n\n\n\n\n\n∂\n\n\nv\n\n\nr\n\n\n\n\n∂\nθ\n\n\n\n−\n\n\nv\n\n\nθ\n\n\n\n\n\n\nσ\n\n\nr\nθ\n\n\n\n\n\n\n\n+\n\n\n\n\n1\n\n\nr\n\n\n\n\n\n\n∂\n\n\nv\n\n\nϕ\n\n\n\n\n∂\nθ\n\n\n\n\n\nσ\n\n\nθ\nϕ\n\n\n−\n\n\n\n\n\nv\n\n\nϕ\n\n\n\n\nr\n\n\n\n\n\n\n\nσ\n\n\nr\nϕ\n\n\n+\n\n\nσ\n\n\nθ\nϕ\n\n\ncot\nθ\n\n\n\n\n\n\n\n+\n\n\n\n\n1\n\n\n\n\nr\n\n\n2\n\n\n\n\n\n\n\n\n∂\n\n\n∂\nr\n\n\n\n\n\n\n\nr\n\n\n2\n\n\nλ\n\n\n\n∂\nT\n\n\n∂\nr\n\n\n\n\n\n+\n\n\n\n1\n\n\nr\nsin\nθ\n\n\n\n\n\n\n∂\n\n\n∂\nθ\n\n\n\n\n\n\n\n\nλ\nsin\nθ\n\n\nr\n\n\n\n\n\n\n∂\nT\n\n\n∂\nθ\n\n\n\n\n\n.\n\n\n\n\n\n\n","Citation Text":["Yuan et al. 2012a"],"Citation Start End":[[1127,1144]]} {"Identifier":"2015AandA...581A..90T__Winget_et_al._(2009)_Instance_1","Paragraph":"NGC 6397 is the second-nearest globular cluster to the Sun and has been thoroughly observed by the Hubble Space Telescope. Thus, we have high-quality deep images for it that have allowed us to study not only the lower main sequence, but also the white dwarf cooling sequence. NGC 6397 is old and metal-poor, its metallicity is [ Fe\/H ] = −1.8 (Hansen et al. 2013), although there exists some discrepancy about its precise value (Richer et al. 2008) in the recent literature. The same is true for the age of the cluster. For instance, Hansen et al. (2007) analyzed the position of the cutoff of the white dwarf luminosity function and, comparing this with theoretical cooling models, derived an age Tc = 11.47 ± 0.47 Gyr. Similarly, Winget et al. (2009) simultaneously fitted the main-sequence, the pre-white dwarf, and the white dwarf regions of the color–magnitude diagram, and obtained an age \\hbox{$T_{\\rm c}=12.0^{+0.5}_{-1.0}$}Tc=12.0-1.0+0.5 Gyr. These ages, which are based on white dwarf evolutionary models, need to be compared with those obtained by fitting the luminosity of the main-sequence turn-off (MSTO) – see Richer et al. (2008) for a discussion of different methods and age estimates of NGC 6397. In particular, it is worth highlighting that using this method, Gratton et al. (2003) derived an age of 13.9 ± 1.1 Gyr. This prompted Strickler et al. (2009) to claim that this age determination was compatible with the possible existence of a putative population of very old helium white dwarfs. On the other hand, Anthony-Twarog & Twarog (2000) obtained 12.0 ± 0.8 Gyr and Chaboyer et al. (2001) derived 13.4 ± 0.8 Gyr. Thus, the precise age of NGC 6397 remains unclear and needs to be independently evaluated using the most recent white dwarf evolutionary tracks of the appropriate metallicity. To this we add that NGC 6397 shares some other interesting characteristics with other Galactic globular clusters, such as the unusual lithium enhancement of some of their stars – see Pasquini et al. (2014) and references therein – or the possible existence of multiple populations (di Criscienzo et al. 2010; Milone et al. 2012). Thus, deriving an independent white dwarf cooling age for this globular cluster is of crucial importance. ","Citation Text":["Winget et al. (2009)"],"Citation Start End":[[734,754]]} {"Identifier":"2015ApJ...798..107K__Neidig_et_al._1993_Instance_1","Paragraph":"As reported in Section 2.4, the uncertainties introduced by chromatic aberration in our observations prevented an unambiguous determination of the detailed characteristics of the spectral slope at wavelengths in the Balmer continuum range (λ 3646 Å). However, we do note the apparent lack of a jump in excess intensity or flare contrast at λ   3646 Å relative to the intensity at redder wavelengths (Figure 9). A dominant optically thin 10,000 K spectrum would have produced a large Balmer jump ratio (i.e., the ratio of intensity at blue wavelengths to that at red wavelengths of 3646 Å) that is ∼14 (Kunkel 1970; Neidig et al. 1993); we think that this should have been noticeable even with the data quality degraded due to chromatic aberration at λ   3646 Å. It is possible that in our spectra the blending of Stark-broadened high-order Balmer lines77The spectral region from 3654–3674 Å contains the rapidly converging hydrogen Balmer lines H23 through at least H40; the center wavelengths of H23 and H24 are separated by ∼2.5 Å whereas H39 and H40 are separated by only 0.5 Å. combined with the Stark broadening of the Balmer recombination edge could smear the Balmer jump making it non-detectable. Still, we note that other WL flares reported in the literature either did not display a Balmer jump, or had other properties not readily explained by a Hydrogen recombination spectrum. In particular, a strong blue continuum emission at λ 4000 Å has been often reported (Hiei 1982; Neidig & Wiborg 1984), and shown by Donati-Falchi et al. (1985) as the result of the blending of Stark-broadened high-order Balmer lines in a dense chromosphere. In the model of Donati-Falchi et al. (1985), this “bump” in the blue continuum peaks at λ  ∼  3675 Å and becomes more prominent and shifts to redder wavelengths as electron density in the flare region increases. Existing models of Stark broadening imply that such blue “continuum” emission originates from a location with electron density in excess of 1013 cm−3 and electron temperature between 7000 and 10,000 K. Interestingly, in our excess spectra we observe a relatively featureless, broad bump peaking at λ ∼ 3675 Å (Figure 9). Taken at face value, the electron densities inferred from interpreting this feature via Stark broadening appear at odd with those derived in Section 5.2, unless more optically thin features such as the higher order Balmer lines probe different portions of the flaring atmosphere. However, additional spectra that are not affected by chromatic aberration will be needed to confirm and understand this feature.","Citation Text":["Neidig et al. 1993"],"Citation Start End":[[635,653]]} {"Identifier":"2019AandA...631A..90L__Christiansen_et_al._(2018)_Instance_1","Paragraph":"K2-138 is a remarkable dynamical system with five planets in a chain close to the 3:2 resonance. In addition, these planets form a chain of three-body Laplace resonances (Christiansen et al. 2018). This makes K2-138 an ideal target to study transit timing variations. We estimated the transit timing variations using the TTVFaster code (Agol & Deck 2016). We first assumed zero eccentricities for the six planets and took the median masses from Table A.2. We found amplitudes of the order of 2.0, 4.1, 7.3,4.5, 6.4, and 0.02 min for planets from b to g, respectively. Then, assuming median eccentricities from Table A.2, we obtained amplitudes of the order 34, 42, 66, 37, and 41 min for planets b to f (Fig. 9). These amplitudes are excluded by K2 observations which do not show any significant variations at the level of 8–10 min, asdemonstrated by Christiansen et al. (2018). Therefore, the planets are likely close to circular orbits, which is compatible with the posterior distributions we obtained. This is also in line with results showing that tightly packed multi-transiting planets have low eccentricities (Van Eylen et al. 2019). Finally, using the upper limits derived for the masses of planets f and g, we computed the corresponding TTVs of planets e and f. Planet g does not impact TTVs of planet f in a significant (detectable) way as it is far from resonance, being located after a double gap in the chain of resonance. Therefore, it is not possible to use TTVs of planet f to constrain the mass of planet g even if there are undetected and non-transiting planets filling the gap in the chain. Still assuming circular orbits, TTVs of planet e reach an amplitude of the order eight minutes only for masses of planet f above 12 M⊕, which is above the upper limit we derived. However, as we cannot exclude an absorption of the signal of planet f by the GP, it is more conservative to include masses for planet f up to around 12 M⊕. Using the upper limit mass for planet f, the predicted TTVs of planet e are of the order of 6.4 min, and using the median mass they are of 4.5 min. Both are well within reach of space mission like CHEOPS which has a cadence of up to 60 s. Observations of transits of planet e using CHEOPS would be beneficial to constrain further the mass of planet f through a photodynamical analysis (Barros et al. 2015). Additionally, more transit observations, with a higher cadence, of planets b, c and d would allow to constrain the masses of planets c, d and e from TTVs which would make K2-138 an interesting benchmark system for comparing RV and TTV masses. This would allow to better calibrate the two mass measurement techniques. Nevertheless, at this stage, and without more precise photometric observationsof planets e and f, an analysis including TTVs would not allow to measure the masses of planets f and g.","Citation Text":["Christiansen et al. 2018"],"Citation Start End":[[171,195]]} {"Identifier":"2019AandA...631A..90L__Christiansen_et_al._(2018)_Instance_2","Paragraph":"K2-138 is a remarkable dynamical system with five planets in a chain close to the 3:2 resonance. In addition, these planets form a chain of three-body Laplace resonances (Christiansen et al. 2018). This makes K2-138 an ideal target to study transit timing variations. We estimated the transit timing variations using the TTVFaster code (Agol & Deck 2016). We first assumed zero eccentricities for the six planets and took the median masses from Table A.2. We found amplitudes of the order of 2.0, 4.1, 7.3,4.5, 6.4, and 0.02 min for planets from b to g, respectively. Then, assuming median eccentricities from Table A.2, we obtained amplitudes of the order 34, 42, 66, 37, and 41 min for planets b to f (Fig. 9). These amplitudes are excluded by K2 observations which do not show any significant variations at the level of 8–10 min, asdemonstrated by Christiansen et al. (2018). Therefore, the planets are likely close to circular orbits, which is compatible with the posterior distributions we obtained. This is also in line with results showing that tightly packed multi-transiting planets have low eccentricities (Van Eylen et al. 2019). Finally, using the upper limits derived for the masses of planets f and g, we computed the corresponding TTVs of planets e and f. Planet g does not impact TTVs of planet f in a significant (detectable) way as it is far from resonance, being located after a double gap in the chain of resonance. Therefore, it is not possible to use TTVs of planet f to constrain the mass of planet g even if there are undetected and non-transiting planets filling the gap in the chain. Still assuming circular orbits, TTVs of planet e reach an amplitude of the order eight minutes only for masses of planet f above 12 M⊕, which is above the upper limit we derived. However, as we cannot exclude an absorption of the signal of planet f by the GP, it is more conservative to include masses for planet f up to around 12 M⊕. Using the upper limit mass for planet f, the predicted TTVs of planet e are of the order of 6.4 min, and using the median mass they are of 4.5 min. Both are well within reach of space mission like CHEOPS which has a cadence of up to 60 s. Observations of transits of planet e using CHEOPS would be beneficial to constrain further the mass of planet f through a photodynamical analysis (Barros et al. 2015). Additionally, more transit observations, with a higher cadence, of planets b, c and d would allow to constrain the masses of planets c, d and e from TTVs which would make K2-138 an interesting benchmark system for comparing RV and TTV masses. This would allow to better calibrate the two mass measurement techniques. Nevertheless, at this stage, and without more precise photometric observationsof planets e and f, an analysis including TTVs would not allow to measure the masses of planets f and g.","Citation Text":["Christiansen et al. (2018)"],"Citation Start End":[[851,877]]} {"Identifier":"2019AandA...631A..9Agol_&_Deck_2016_Instance_1","Paragraph":"K2-138 is a remarkable dynamical system with five planets in a chain close to the 3:2 resonance. In addition, these planets form a chain of three-body Laplace resonances (Christiansen et al. 2018). This makes K2-138 an ideal target to study transit timing variations. We estimated the transit timing variations using the TTVFaster code (Agol & Deck 2016). We first assumed zero eccentricities for the six planets and took the median masses from Table A.2. We found amplitudes of the order of 2.0, 4.1, 7.3,4.5, 6.4, and 0.02 min for planets from b to g, respectively. Then, assuming median eccentricities from Table A.2, we obtained amplitudes of the order 34, 42, 66, 37, and 41 min for planets b to f (Fig. 9). These amplitudes are excluded by K2 observations which do not show any significant variations at the level of 8–10 min, asdemonstrated by Christiansen et al. (2018). Therefore, the planets are likely close to circular orbits, which is compatible with the posterior distributions we obtained. This is also in line with results showing that tightly packed multi-transiting planets have low eccentricities (Van Eylen et al. 2019). Finally, using the upper limits derived for the masses of planets f and g, we computed the corresponding TTVs of planets e and f. Planet g does not impact TTVs of planet f in a significant (detectable) way as it is far from resonance, being located after a double gap in the chain of resonance. Therefore, it is not possible to use TTVs of planet f to constrain the mass of planet g even if there are undetected and non-transiting planets filling the gap in the chain. Still assuming circular orbits, TTVs of planet e reach an amplitude of the order eight minutes only for masses of planet f above 12 M⊕, which is above the upper limit we derived. However, as we cannot exclude an absorption of the signal of planet f by the GP, it is more conservative to include masses for planet f up to around 12 M⊕. Using the upper limit mass for planet f, the predicted TTVs of planet e are of the order of 6.4 min, and using the median mass they are of 4.5 min. Both are well within reach of space mission like CHEOPS which has a cadence of up to 60 s. Observations of transits of planet e using CHEOPS would be beneficial to constrain further the mass of planet f through a photodynamical analysis (Barros et al. 2015). Additionally, more transit observations, with a higher cadence, of planets b, c and d would allow to constrain the masses of planets c, d and e from TTVs which would make K2-138 an interesting benchmark system for comparing RV and TTV masses. This would allow to better calibrate the two mass measurement techniques. Nevertheless, at this stage, and without more precise photometric observationsof planets e and f, an analysis including TTVs would not allow to measure the masses of planets f and g.","Citation Text":["Agol & Deck 2016"],"Citation Start End":[[337,353]]} {"Identifier":"2019AandA...631A..9Van_Eylen_et_al._2019_Instance_1","Paragraph":"K2-138 is a remarkable dynamical system with five planets in a chain close to the 3:2 resonance. In addition, these planets form a chain of three-body Laplace resonances (Christiansen et al. 2018). This makes K2-138 an ideal target to study transit timing variations. We estimated the transit timing variations using the TTVFaster code (Agol & Deck 2016). We first assumed zero eccentricities for the six planets and took the median masses from Table A.2. We found amplitudes of the order of 2.0, 4.1, 7.3,4.5, 6.4, and 0.02 min for planets from b to g, respectively. Then, assuming median eccentricities from Table A.2, we obtained amplitudes of the order 34, 42, 66, 37, and 41 min for planets b to f (Fig. 9). These amplitudes are excluded by K2 observations which do not show any significant variations at the level of 8–10 min, asdemonstrated by Christiansen et al. (2018). Therefore, the planets are likely close to circular orbits, which is compatible with the posterior distributions we obtained. This is also in line with results showing that tightly packed multi-transiting planets have low eccentricities (Van Eylen et al. 2019). Finally, using the upper limits derived for the masses of planets f and g, we computed the corresponding TTVs of planets e and f. Planet g does not impact TTVs of planet f in a significant (detectable) way as it is far from resonance, being located after a double gap in the chain of resonance. Therefore, it is not possible to use TTVs of planet f to constrain the mass of planet g even if there are undetected and non-transiting planets filling the gap in the chain. Still assuming circular orbits, TTVs of planet e reach an amplitude of the order eight minutes only for masses of planet f above 12 M⊕, which is above the upper limit we derived. However, as we cannot exclude an absorption of the signal of planet f by the GP, it is more conservative to include masses for planet f up to around 12 M⊕. Using the upper limit mass for planet f, the predicted TTVs of planet e are of the order of 6.4 min, and using the median mass they are of 4.5 min. Both are well within reach of space mission like CHEOPS which has a cadence of up to 60 s. Observations of transits of planet e using CHEOPS would be beneficial to constrain further the mass of planet f through a photodynamical analysis (Barros et al. 2015). Additionally, more transit observations, with a higher cadence, of planets b, c and d would allow to constrain the masses of planets c, d and e from TTVs which would make K2-138 an interesting benchmark system for comparing RV and TTV masses. This would allow to better calibrate the two mass measurement techniques. Nevertheless, at this stage, and without more precise photometric observationsof planets e and f, an analysis including TTVs would not allow to measure the masses of planets f and g.","Citation Text":["Van Eylen et al. 2019"],"Citation Start End":[[1117,1138]]} {"Identifier":"2019AandA...631A..9Barros_et_al._2015_Instance_1","Paragraph":"K2-138 is a remarkable dynamical system with five planets in a chain close to the 3:2 resonance. In addition, these planets form a chain of three-body Laplace resonances (Christiansen et al. 2018). This makes K2-138 an ideal target to study transit timing variations. We estimated the transit timing variations using the TTVFaster code (Agol & Deck 2016). We first assumed zero eccentricities for the six planets and took the median masses from Table A.2. We found amplitudes of the order of 2.0, 4.1, 7.3,4.5, 6.4, and 0.02 min for planets from b to g, respectively. Then, assuming median eccentricities from Table A.2, we obtained amplitudes of the order 34, 42, 66, 37, and 41 min for planets b to f (Fig. 9). These amplitudes are excluded by K2 observations which do not show any significant variations at the level of 8–10 min, asdemonstrated by Christiansen et al. (2018). Therefore, the planets are likely close to circular orbits, which is compatible with the posterior distributions we obtained. This is also in line with results showing that tightly packed multi-transiting planets have low eccentricities (Van Eylen et al. 2019). Finally, using the upper limits derived for the masses of planets f and g, we computed the corresponding TTVs of planets e and f. Planet g does not impact TTVs of planet f in a significant (detectable) way as it is far from resonance, being located after a double gap in the chain of resonance. Therefore, it is not possible to use TTVs of planet f to constrain the mass of planet g even if there are undetected and non-transiting planets filling the gap in the chain. Still assuming circular orbits, TTVs of planet e reach an amplitude of the order eight minutes only for masses of planet f above 12 M⊕, which is above the upper limit we derived. However, as we cannot exclude an absorption of the signal of planet f by the GP, it is more conservative to include masses for planet f up to around 12 M⊕. Using the upper limit mass for planet f, the predicted TTVs of planet e are of the order of 6.4 min, and using the median mass they are of 4.5 min. Both are well within reach of space mission like CHEOPS which has a cadence of up to 60 s. Observations of transits of planet e using CHEOPS would be beneficial to constrain further the mass of planet f through a photodynamical analysis (Barros et al. 2015). Additionally, more transit observations, with a higher cadence, of planets b, c and d would allow to constrain the masses of planets c, d and e from TTVs which would make K2-138 an interesting benchmark system for comparing RV and TTV masses. This would allow to better calibrate the two mass measurement techniques. Nevertheless, at this stage, and without more precise photometric observationsof planets e and f, an analysis including TTVs would not allow to measure the masses of planets f and g.","Citation Text":["Barros et al. 2015"],"Citation Start End":[[2331,2349]]} {"Identifier":"2022AandA...657A..53B__Baraffe_et_al._2015_Instance_1","Paragraph":"The de-reddened photometry of TYC 8252-533-1 B and its host star are presented in Table 5. The listed Gaia photometry is directly obtained from the EDR3 catalog and the infrared photometry originates from our high-contrast imaging data. We applied the previously determined extinction of AV = 0.13 mag to correct the presented fluxes. As the SPHERE H band data from 2017-04-02 were collected in poor atmospheric conditions and with a very unstable AO performance, we disregarded the photometry that was extracted from these observations in our further analysis. We fitted the full optical and infraredSED of the companion utilizing the MCMC approach described in Bohn et al. (2020b). We used a linearly interpolated grid of BT-Settl models (Allard et al. 2012; Baraffe et al. 2015) with effective temperatures, Teff, between 1500 K and 4000 K, surface gravity in the range of \n\n$0<\\log\\left(g\\right)<6$0log(g)6\n, and solar metallicity. We further allowed object radii R from 0.5 RJup to 5 RJup. The MCMC sampler was implemented in the emcee framework (Foreman-Mackey et al. 2013) and we used 100 walkers with 10 000 steps to sample the posterior distribution. In accordance with the computed autocorrelation time of approximately 200 steps, the first 1000 samples of each chain were discarded as burn-in phase and we further continued using each twentieth step of the remaining chains. This provided 45 000 samples for our posterior distribution in (Teff, \n\n$\\log\\left(g\\right)$log(g)\n, R), which are visualized in Fig. D.1. From these distributions we derived an effective temperature of \n\n$T_{\\textrm{eff}}=3092^{+186}_{-91}\\,K$Teff=3092−91+186 K\n, a surface gravity of \n\n$\\log\\left(g\\right)=3.41^{+1.07}_{-0.31}$log(g)=3.41−0.31+1.07\n dex, and a radius of \n\n$R=3.5^{+0.3}_{-0.4}\\,R_{\\textrm{Jup}}$R=3.5−0.4+0.3 RJup\n for TYC 8252-533-1 B. These values were obtained as the 95% confidence intervals around the medians of the posterior distributions. From these three parameters we derived the object luminosity as \n\n$\\log\\left(L_*\/L_{\\odot}\\right)=-1.99^{+0.01}_{-0.02}$log(L*\/L⊙)=−1.99−0.02+0.01\n. The results of this SED fit are presented in Fig. 9. Interestingly, the derived object radius is markedly larger than usual radii of field brown dwarfs of this mass, which are on the order of 1 RJup (e.g., Chabrier et al. 2009). This inflated photometric radius, however, is nothing unusual for sub-stellar companions at this young age, and similarly large values have been reported for various planetary-mass objects (e.g., Schmidt et al. 2008; Bohn et al. 2019; Stolker et al. 2020).","Citation Text":["Baraffe et al. 2015"],"Citation Start End":[[761,780]]} {"Identifier":"2015ApJ...805...88Y__Geng_et_al._2013_Instance_1","Paragraph":"In our study, the central engine of GRB 100814A is assumed to be a newborn magnetar with spin evolution. The early-time optical shallow decay phase and X-ray plateau come from the initial spin-down process and the late-time optical rebrightening results from the enhanced energy injection generated by the spinning up of the magnetar. When calculating the dynamic process of the multi-band afterglow of GRB 100814A, we use the Equations for beamed GRB outflows developed by Huang et al. (1999, 2000) considering continuous energy injection from the central magnetar with spin evolution. The bulk Lorentz factor (γ) of the shocked interstellar medium is described by the following differential Equation (for details, see Huang et al. 1999):\n6\n\n\n\n\n\nwhere Mej is the initial ejecta mass, m is the swept-up interstellar medium mass, and is the radiative efficiency. When the energy injection due to the magnetic dipole radiation from the central magnetar is taken into account, the above differential Equation can be modified to be (Kong & Huang 2010; Geng et al. 2013)\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n can be calculated from Equation (1). In our calculations, several effects, such as lateral expansion, electron synchrotron cooling, and equal arrival time surfaces, have been incorporated. In the absence of electron synchrotron cooling, the comoving frame distribution of the shock-accelerated electrons is usually assumed to be a power-law function, \n\n\n\n\n\n, where p is the power-law index. After considering the electron synchrotron cooling effect, the distribution function will be changed to \n\n\n\n\n\n for electrons above a critical Lorentz factor \n\n\n\n\n\n (Sari et al. 1998). For detailed description of electron distribution, see Huang et al. (2000) and Huang & Cheng (2003). We neglect the adiabatic pressure and energy losses due to adiabatic expansion, which might also have a minor effect on the dynamical evolution of the blast wave (van Eerten et al. 2010; Pe’er 2012; Nava et al. 2013). For radiative process, the multi-band afterglow emission mainly comes from synchrotron radiation of the shock-accelerated electrons due to their interaction with the magnetic field (Sari et al. 1998; Sari & Piran 1999). We present our numerical results below.","Citation Text":["Geng et al. 2013"],"Citation Start End":[[1049,1065]]} {"Identifier":"2022ApJ...933..111T__Fujimoto_et_al._2007_Instance_1","Paragraph":"For the first step, we adopted the nucleosynthesis calculation for around 4070 nuclei performed by Fujimoto et al. (2007), which was cooled using the adiabatic expansion modeled from Freiburghaus et al. (1999) to provide the elemental composition ratios of nuclei for Y\ne = 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, and 0.45. This estimation assumes that the initial environment has a temperature of 9 × 109 K, a radius of 100 km, entropy per baryon of 10 k\nB, where k\nB is the Boltzmann constant, and a velocity of 2 × 109 cm s−1, along with the initial abundances of the 4070 nuclei in nuclear statistical equilibrium. As a result, the calculation provides the mass fractions at t = 1 yr evaluated with the nuclear reaction network (network A in Fujimoto et al. 2007), by using Y\ne = 0.10–0.45 in steps of 0.05. To set up the mass distribution of nuclei for the NSMs at t = 1 yr, we blended the nuclei with the mass fraction using the Y\ne provided in Wanajo et al. (2014). Specifically, the fractions are 4.54%, 4.85%, 14.6%, 29.7%, 10.3%, 25.1%, 10.5%, and 0.33% for Y\ne = 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, and 0.45, respectively. Note that this Y\ne-fraction model by Wanajo et al. (2014) describes a slightly less neutron-rich environment than those by the recent dynamical-ejecta models after the kilonova observations of the gravitational event GW170817, such as four models in Kullmann et al. (2022) under two kinds of equations of state, density dependent 2 (DD2; Hempel & Schaffner-Bielich 2010; Typel et al. 2010), and SFHo (Steiner et al. 2013). In this paper, we adopted the first one by Wanajo et al. (2014) as a pessimistic case for the r-process site, but changing the Y\ne-fraction models does not change the conclusions from the gamma-ray spectra as tested in Section 3. Figure 1 shows the mass fraction of multiple nuclei at t = 1 yr generated in an NSM case, information that is given in the table of nuclides (neutron number N versus atomic number Z). Using the same data set, Figure 2 summarizes the distribution of nuclei with mass number A at t = 1 yr, showing the contributions of Y\ne. This plot demonstrates that the environment with lower Y\ne contributes to the generation of heavier elements.","Citation Text":["Fujimoto et al. (2007)"],"Citation Start End":[[99,121]]} {"Identifier":"2022ApJ...933..111T__Fujimoto_et_al._2007_Instance_2","Paragraph":"For the first step, we adopted the nucleosynthesis calculation for around 4070 nuclei performed by Fujimoto et al. (2007), which was cooled using the adiabatic expansion modeled from Freiburghaus et al. (1999) to provide the elemental composition ratios of nuclei for Y\ne = 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, and 0.45. This estimation assumes that the initial environment has a temperature of 9 × 109 K, a radius of 100 km, entropy per baryon of 10 k\nB, where k\nB is the Boltzmann constant, and a velocity of 2 × 109 cm s−1, along with the initial abundances of the 4070 nuclei in nuclear statistical equilibrium. As a result, the calculation provides the mass fractions at t = 1 yr evaluated with the nuclear reaction network (network A in Fujimoto et al. 2007), by using Y\ne = 0.10–0.45 in steps of 0.05. To set up the mass distribution of nuclei for the NSMs at t = 1 yr, we blended the nuclei with the mass fraction using the Y\ne provided in Wanajo et al. (2014). Specifically, the fractions are 4.54%, 4.85%, 14.6%, 29.7%, 10.3%, 25.1%, 10.5%, and 0.33% for Y\ne = 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, and 0.45, respectively. Note that this Y\ne-fraction model by Wanajo et al. (2014) describes a slightly less neutron-rich environment than those by the recent dynamical-ejecta models after the kilonova observations of the gravitational event GW170817, such as four models in Kullmann et al. (2022) under two kinds of equations of state, density dependent 2 (DD2; Hempel & Schaffner-Bielich 2010; Typel et al. 2010), and SFHo (Steiner et al. 2013). In this paper, we adopted the first one by Wanajo et al. (2014) as a pessimistic case for the r-process site, but changing the Y\ne-fraction models does not change the conclusions from the gamma-ray spectra as tested in Section 3. Figure 1 shows the mass fraction of multiple nuclei at t = 1 yr generated in an NSM case, information that is given in the table of nuclides (neutron number N versus atomic number Z). Using the same data set, Figure 2 summarizes the distribution of nuclei with mass number A at t = 1 yr, showing the contributions of Y\ne. This plot demonstrates that the environment with lower Y\ne contributes to the generation of heavier elements.","Citation Text":["Fujimoto et al. 2007"],"Citation Start End":[[749,769]]} {"Identifier":"2021MNRAS.503.5473A__Illarionov_&_Siuniaev_1975_Instance_1","Paragraph":"In this section, we study the feasibility of detecting non-thermal SZ with future CMB experiments. The distortion in intensity Iν of CMB at a frequency ν and towards a localized concentration of hot electrons can be written as,\n(19)$$\\begin{eqnarray*}\r\n\\Delta I_{\\nu }=\\Delta I_{\\rm {y}}+\\Delta I_{\\rm {\\mu }}+\\Delta I_{\\rm {kSZ}}+\\Delta I_{\\rm {rSZ}}+\\Delta I_{\\rm {NT}},\r\n\\end{eqnarray*}$$where ΔIy is the typically dominant non-relativistic y distortion, ΔIμ is the μ distortion, ΔIkSZ is the temperature shift of the CMB blackbody due to kSZ effect (Sunyaev & Zeldovich 1980), ΔIrSZ is the relativistic SZ signal from a massive galaxy cluster, and ΔINT is the non-thermal SZ distortion. The expression for ΔIy, ΔIμ, and ΔIkSZ are given by (Zeldovich & Sunyaev 1969; Sunyaev & Zeldovich 1970; Illarionov & Siuniaev 1975),\n(20)$$\\begin{eqnarray*}\r\n\\Delta I_{\\rm {y}}=y\\frac{2\\rm {h}{\\nu }^3}{\\rm {c^2}}\\frac{x\\rm {e^x}}{(\\rm {e^x}-1)^2}\\left[x\\frac{\\rm {e^x}+1}{\\rm {e^x}-1}-4\\right]\r\n\\end{eqnarray*}$$(21)$$\\begin{eqnarray*}\r\n\\Delta I_{\\rm {\\mu }}=\\mu \\frac{2\\rm {h}{\\nu }^3}{\\rm {c^2}}\\frac{\\rm {e^x}}{(\\rm {e^x}-1)^2}\\left[\\frac{x}{2.19}-1\\right]\r\n\\end{eqnarray*}$$(22)$$\\begin{eqnarray*}\r\n\\Delta I_{\\rm {kSZ}}=\\left(\\frac{\\Delta T}{T}\\right)\\frac{2\\rm {h}{\\nu }^3}{\\rm {c^2}}\\frac{\\rm {e^x}}{(\\rm {e^x}-1)^2}\r\n.\r\n\\end{eqnarray*}$$The y-distortion can have contribution from both pre-recombination Universe as well as post-recombination Universe while μ-distortion can only be created at redshifts greater than 2 × 105. The SZ spectrum from electrons with energy ≳keV is obtained by including Klein–Nishina corrections for Compton scattering which can be calculated perturbatively as an expansion in $\\frac{T_{\\rm {e}}}{m_{\\rm {e}}}$ (Challinor & Lasenby 1998; Itoh, Kohyama & Nozawa 1998; Sazonov & Sunyaev 1998; Dolgov et al. 2001). For example, the temperature of massive galaxy cluster with mass 1014 times solar mass can be ∼5 keV (Erler et al. 2018), and with a typical y ∼ 10−5.","Citation Text":["Illarionov & Siuniaev 1975"],"Citation Start End":[[796,822]]} {"Identifier":"2022ApJ...924...39M__Mapelli_et_al._2021_Instance_1","Paragraph":"Stars with masses 130 M\n⊙ ≲ M\nZAMS ≲ 250 M\n⊙ are subject to the pair instability, which disrupts them completely, and hence no BH forms. Stars with M\nZAMS ≳ 250 M\n⊙ can collapse directly to IMBHs with a mass ≳135 M\n⊙. Thus, in the standard picture, there should be an upper stellar-mass BH gap in the range [65, 135] M\n⊙, and any BHs observed in this range (e.g., the primary BH of GW190521) have to form via other formation channels—for example, through hierarchical coalescence of smaller BHs or direct collapse of a stellar merger between an evolved star and a main-sequence companion (e.g., Quinlan & Shapiro 1989; Portegies Zwart & McMillan 2000; Ebisuzaki et al. 2001; Miller & Hamilton 2002; O’Leary et al. 2006; Gerosa & Berti 2017; Antonini et al. 2019; Di Carlo et al. 2019, 2020; Rodriguez et al. 2019; Gayathri et al. 2020a; Kimball et al. 2021; Mapelli et al. 2021). However, the exact mass boundaries of the gap depend on parameters that are uncertain. For example, the 12C(α, γ)16O nuclear reaction rate, which converts carbon to oxygen in the core, can affect the boundary significantly (Takahashi 2018; Farmer et al. 2020; Costa et al. 2021; Woosley & Heger 2021). Here, to better determine whether future GW observations will be able to observe BHs in the mass gap, we recompute the mass-gap boundaries with updated 12C(α, γ)16O reaction rates and increased mass and temporal resolution. The complexity of this system has made a reliable analysis of the reaction a decades-old challenge.\n7\n\n\n7\nThe reaction rate for 12C(α, γ)16O is determined by the quantum structure of the compound nucleus 16O as an α cluster system. It is characterized by the interfering ℓ = 1 waves of the J\n\nπ\n = 1− resonances and sub-threshold levels defining an E1 component for the reaction cross section as well as by the ℓ = 2 components and interference from broad J\n\nπ\n = 2+ resonances and the nonresonant E2 external capture to the ground state of 16O. In addition to these two main E1 and E2 ground-state components, transitions to higher lying excited states occur that also add to the total cross section (see, e.g., Buchmann & Barnes 2006; deBoer et al. 2017). The rapidly declining cross section at low energies has prohibited a direct measurement of the reaction at stellar temperatures, and the reaction rate is entirely based on the theoretical analysis and extrapolation of the experimental data toward lower energies. The rate newly derived by deBoer et al. (2017), using a multichannel analysis approach, derives for the first time a reliable prediction for the interference patterns within the reaction components by taking into account all available experimental data sets that cover the near-threshold energy range of the 12C(α, γ)16O process.","Citation Text":["Mapelli et al. 2021"],"Citation Start End":[[858,877]]} {"Identifier":"2016MNRAS.463..696L__Yadav_et_al._2008_Instance_1","Paragraph":"Another possible explanation for the peculiar solar composition is that some of the dust in the pre-solar nebula was radiatively cleansed by luminous hot stars in the solar neighbourhood before the formation of the Sun and its planets. This dust-cleansing scenario is supported by the finding that the open cluster M67 seems to have a chemical composition closer to the solar composition than most solar twins (Önehag et al. 2011, hereafter O11 and Önehag, Gustafsson & Korn 2014, hereafter O14). They suggested that the proto-solar nebula was dust-cleansed by massive stars, similar to what happened for the proto-cluster cloud of M67, while the majority of solar twins in the field would presumably have formed in less massive clusters where no nearby high-mass star (≥15 M⊙) was formed. M67 offers the possibility for studying the solar-type stars in a dense cluster environment. This cluster has about solar metallicity ([Fe\/H] in the range −0.04 to +0.03, e.g. Hobbs & Thorburn 1991; Yong, Carney & Teixera de Almeida 2005; Randich et al. 2006; Pasquini et al. 2008). The age of M67 is also comparable with that of the Sun: 3.5–4.8 Gyr (Yadav et al. 2008). Pasquini et al. (2008) listed 10 solar-twin candidates in M67, including M67-1194 which hosts a hot Jupiter with a period of 6.9 d and a minimum mass of 0.34 MJup (Brucalassi et al. 2014). M67-1194 was studied by O11 and re-visited by O14. They found that unlike nearby solar twins, which were systematically analysed by Meléndez et al. (2009) and Ramírez, Meléndez & Asplund (2009), the chemical composition of M67-1194 is more solar-like and therefore suggested that the Sun may have been formed in a similar cluster environment, perhaps even in M67. While this scenario is plausible when considering chemical abundances and ages, the dynamics are problematic: the Sun has an orbit close to the Galactic plane, while M67 is presently some 450 pc above the plane. The probability that the Sun, if formed in M67 with an orbit similar to the present cluster orbit, was scattered or diffused out of the cluster into the present solar orbit, is found to be quite low, if the existence of the outer planetary system is taken into account (Pichardo et al. 2012). Gustafsson et al. (2016) suggested that the high-altitude metal-rich clusters (such as M67) were formed in orbits close to the Galactic plane and later scattered to higher orbits by interaction with giant molecular clouds and spiral arms. Thus, it is possible, though not very probable, that the Sun formed in such a cluster before scattering occurred. Currently, only one solar twin in M67 (M67-1194) was spectroscopically analysed with high precision (∼0.02 dex). It is thus crucial to analyse the chemical composition of additional solar-type stars in M67 of very high precision.","Citation Text":["Yadav et al. 2008"],"Citation Start End":[[1142,1159]]} {"Identifier":"2015MNRAS.446...38G__Binney_&_Tremaine_1987_Instance_1","Paragraph":"Let us consider a SMBH with mass MBH kicked with velocity vk from the galactic centre (r = 0). The SMBH will be ejected from the galactic halo if vk exceeds the escape velocity of the system:\n\n(33)\n\n\\begin{eqnarray}\nv_{\\rm esc}= \\sqrt{2G\\left( \\frac{M_{\\rm BCG}}{r_{\\rm H}} + c \\,g_{\\rm c} \\frac{M_{\\rm DM}}{r_{\\rm v}}\\right)} \\,.\n\\end{eqnarray}\n\nIf vk vesc, the SMBH will stop at a distance rmax from the centre. Gualandris & Merritt (2008) showed that the maximum displacement rmax can be estimated simply through energy conservation neglecting star friction (see their fig. 2):\n\n(34)\n\n\\begin{eqnarray}\n\\frac{1}{2} v_{\\rm k}^{2}+\\phi (0)=\\phi (r_{\\rm max})\\,.\n\\end{eqnarray}\n\nThe initial displacement is reached in a time which is typically 100 times smaller than the sinking time-scale (Gualandris & Merritt 2008) and will be therefore neglected. Here, we estimate the time needed to sink back to r = 0 integrating the DF equation on quasi-circular orbits. The frictional force exerted on to the black hole is given by (e.g. Binney & Tremaine 1987)\n\n(35)\n\n\\begin{eqnarray}\nF(r)=\\frac{4 \\pi G^2 M_{\\rm BH}^2 \\rho (r)\\,\\xi (r) \\ln \\Lambda }{v_{\\rm c}^2(r)}\\,,\n\\end{eqnarray}\n\nwhere $v_{\\rm c}(r)=\\sqrt{r\\, {\\rm d}\\phi \/{\\rm d}r}$ is the circular velocity, ln Λ is the Coulomb logarithm and the factor ξ(r) depends on the stellar velocity distribution. We take ln Λ = 2.5, as observed by Gualandris & Merritt (2008) in the very first phase of their simulated orbits (see also Escala et al. 2004). We assume the velocity distribution to be locally Maxwellian, with velocity dispersion σ(r). Although not exact, the Maxwellian distribution is approached as a consequence of collisionless relaxation processes (Lynden-Bell 1967). Under this assumption, the ξ factor in equation (35) reads (Binney & Tremaine 1987)\n\n(36)\n\n\\begin{eqnarray}\n\\xi (r) = {\\rm erf}\\left[\\frac{v_{\\rm c}(r)}{\\sqrt{2} \\sigma (r)}\\right] - \\sqrt{\\frac{2}{\\pi }}\\frac{v_{\\rm c}(r)}{\\sigma (r)}\\exp \\left[-\\frac{v_{\\rm c}^2(r)}{2\\sigma ^2(r)}\\right]\\,.\n\\end{eqnarray}\n\nThe velocity dispersion σ(r) is computed from our galactic potential using the expression provided by Binney (1980) when isotropy is assumed. The frictional force F(r) is tangential and directed opposite to the SMBH velocity. The SMBH angular momentum L(r) = MBHrvc(r) is lost at the rate dL(r)\/dt = −rF(r) by Newton's third law, causing the SMBH to slowly inspiral while remaining on a quasi-circular orbit. The DF time-scale, over which the SMBH sinks back to the galactic centre r = 0 from its initial position rmax , is thus given by6\n(37)\n\n\\begin{eqnarray}\nt_{\\rm DF}=-\\int _{r_{\\rm max}}^0 \\frac{\\mathrm{d} L(r)}{\\mathrm{d}r} \\frac{1}{r F(r)} \\mathrm{d}r\\,.\n\\end{eqnarray}\n\n","Citation Text":["Binney & Tremaine 1987"],"Citation Start End":[[1029,1051]]} {"Identifier":"2015MNRAS.446...38G__Binney_&_Tremaine_1987_Instance_2","Paragraph":"Let us consider a SMBH with mass MBH kicked with velocity vk from the galactic centre (r = 0). The SMBH will be ejected from the galactic halo if vk exceeds the escape velocity of the system:\n\n(33)\n\n\\begin{eqnarray}\nv_{\\rm esc}= \\sqrt{2G\\left( \\frac{M_{\\rm BCG}}{r_{\\rm H}} + c \\,g_{\\rm c} \\frac{M_{\\rm DM}}{r_{\\rm v}}\\right)} \\,.\n\\end{eqnarray}\n\nIf vk vesc, the SMBH will stop at a distance rmax from the centre. Gualandris & Merritt (2008) showed that the maximum displacement rmax can be estimated simply through energy conservation neglecting star friction (see their fig. 2):\n\n(34)\n\n\\begin{eqnarray}\n\\frac{1}{2} v_{\\rm k}^{2}+\\phi (0)=\\phi (r_{\\rm max})\\,.\n\\end{eqnarray}\n\nThe initial displacement is reached in a time which is typically 100 times smaller than the sinking time-scale (Gualandris & Merritt 2008) and will be therefore neglected. Here, we estimate the time needed to sink back to r = 0 integrating the DF equation on quasi-circular orbits. The frictional force exerted on to the black hole is given by (e.g. Binney & Tremaine 1987)\n\n(35)\n\n\\begin{eqnarray}\nF(r)=\\frac{4 \\pi G^2 M_{\\rm BH}^2 \\rho (r)\\,\\xi (r) \\ln \\Lambda }{v_{\\rm c}^2(r)}\\,,\n\\end{eqnarray}\n\nwhere $v_{\\rm c}(r)=\\sqrt{r\\, {\\rm d}\\phi \/{\\rm d}r}$ is the circular velocity, ln Λ is the Coulomb logarithm and the factor ξ(r) depends on the stellar velocity distribution. We take ln Λ = 2.5, as observed by Gualandris & Merritt (2008) in the very first phase of their simulated orbits (see also Escala et al. 2004). We assume the velocity distribution to be locally Maxwellian, with velocity dispersion σ(r). Although not exact, the Maxwellian distribution is approached as a consequence of collisionless relaxation processes (Lynden-Bell 1967). Under this assumption, the ξ factor in equation (35) reads (Binney & Tremaine 1987)\n\n(36)\n\n\\begin{eqnarray}\n\\xi (r) = {\\rm erf}\\left[\\frac{v_{\\rm c}(r)}{\\sqrt{2} \\sigma (r)}\\right] - \\sqrt{\\frac{2}{\\pi }}\\frac{v_{\\rm c}(r)}{\\sigma (r)}\\exp \\left[-\\frac{v_{\\rm c}^2(r)}{2\\sigma ^2(r)}\\right]\\,.\n\\end{eqnarray}\n\nThe velocity dispersion σ(r) is computed from our galactic potential using the expression provided by Binney (1980) when isotropy is assumed. The frictional force F(r) is tangential and directed opposite to the SMBH velocity. The SMBH angular momentum L(r) = MBHrvc(r) is lost at the rate dL(r)\/dt = −rF(r) by Newton's third law, causing the SMBH to slowly inspiral while remaining on a quasi-circular orbit. The DF time-scale, over which the SMBH sinks back to the galactic centre r = 0 from its initial position rmax , is thus given by6\n(37)\n\n\\begin{eqnarray}\nt_{\\rm DF}=-\\int _{r_{\\rm max}}^0 \\frac{\\mathrm{d} L(r)}{\\mathrm{d}r} \\frac{1}{r F(r)} \\mathrm{d}r\\,.\n\\end{eqnarray}\n\n","Citation Text":["Binney & Tremaine 1987"],"Citation Start End":[[1788,1810]]} {"Identifier":"2022ApJ...935..135B__Miyamoto_&_Nagai_1975_Instance_1","Paragraph":"We consider the MW satellites with parallax and proper-motion measurements from Gaia DR2 (Gaia Collaboration et al. 2018c) and the corresponding galactocentric coordinates and velocities computed and documented by Riley et al. (2019, their Table A.2; see also Li et al. 2020) and Vasiliev & Belokurov (2020). Of these, we only consider the satellites with known dynamical mass estimates (Simon & Geha 2007; Bekki & Stanimirović 2009; Łokas 2009; Erkal et al. 2019). Adopting the initial conditions for galactocentric positions (R, z, ϕ) and velocities (v\n\nR\n, v\n\nz\n, v\n\nϕ\n) as the median values quoted by Riley et al. (2019) and Vasiliev & Belokurov (2020), we simulate the orbits of the galaxies in the combined gravitational potential of the MW halo, disk, and bulge, which are respectively modeled by a spherical NFW (Navarro et al. 1997) profile (virial mass M\n\nh\n = 9.78 × 1011\nM\n⊙, scale radius r\n\nh\n = 16 kpc, and concentration c = 15.3), a Miyamoto−Nagai (Miyamoto & Nagai 1975) profile (mass M\n\nd\n = 9.5 × 1010\nM\n⊙, scale radius a = 4 kpc, and scale height b = 0.3 kpc), and a spherical Hernquist (1990) profile (mass M\n\nb\n = 6.5 × 109\nM\n⊙ and scale radius r\n\nb\n = 0.6 kpc).\n5\n\n\n5\nOur MW potential is similar to GALPY MWPOTENTIAL2014 (Bovy 2015) except for the power-law bulge, which has been replaced by an equivalent Hernquist bulge. The total mass of our fiducial MW model is thus 1.08 × 1012\nM\n⊙. We evolve the positions and velocities of the satellites both forward and backward in time from the present day, using a second-order leap-frog integrator. For simplicity, we ignore the effect of dynamical friction.\n6\n\n\n6\nDynamical friction might play an important role in the orbital evolution of massive satellites like the Large Magellanic Cloud (LMC) and Sgr, pushing their orbital radius farther out in the past. From each individual orbit, we note the time, t\ncross, when the satellite crosses the disk (i.e., crosses z = 0) and record the corresponding distance, x\nP, from the Sun, which we integrate backward\/forward in time using a purely circular orbit up to t\ncross. We also record the velocity, \n\n\n\nvP=vR2+vz2+vϕ2\n\n, and the angle of impact with respect to the disk normal, \n\n\n\nθP=cos−1(vz\/vP)\n\n. Finally, we compute the disk response to the satellite encounter using Equation (49). Results are summarized in Table 1 and Figures 6 and 7.","Citation Text":["Miyamoto & Nagai 1975"],"Citation Start End":[[964,985]]} {"Identifier":"2020MNRAS.491..560D__Trigilio,_Umana_&_Migenes_1993_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Trigilio, Umana & Migenes 1993"],"Citation Start End":[[1107,1137]]} {"Identifier":"2020MNRAS.491..560DOsten_2008_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Osten 2008"],"Citation Start End":[[134,144]]} {"Identifier":"2020MNRAS.491..560DVilladsen_&_Hallinan_(2019)_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Villadsen & Hallinan (2019)"],"Citation Start End":[[289,316]]} {"Identifier":"2020MNRAS.491..560DZic_et_al._(2019)_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Zic et al. (2019)"],"Citation Start End":[[407,424]]} {"Identifier":"2020MNRAS.491..560DHall_1976_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Hall 1976"],"Citation Start End":[[777,786]]} {"Identifier":"2020MNRAS.491..560DGunn_1996_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Gunn 1996"],"Citation Start End":[[1206,1215]]} {"Identifier":"2020MNRAS.491..560DCoppejans_et_al._2016_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Coppejans et al. 2016"],"Citation Start End":[[1368,1389]]} {"Identifier":"2020MNRAS.491..560DMooley_et_al._2017_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["Mooley et al. 2017"],"Citation Start End":[[1552,1570]]} {"Identifier":"2020MNRAS.491..560DO’Brien_et_al._2015_Instance_1","Paragraph":"One type of radio transient expected to be found in image plane transient searches is flares from stars and stellar systems (see e.g. Osten 2008, for a summary). Radio flare stars are usually M-type dwarf stars that emit coherent radio bursts on time-scales of minutes to hours. Recently, Villadsen & Hallinan (2019) detected 22 coherent radio bursts from M dwarfs using the VLA at 300 MHz and 1–6 GHz, and Zic et al. (2019) detected several pulses from the M-dwarf UV Ceti with ASKAP. As well as flare stars, binary systems such as RS Canum Venaticorum (RS CVn), cataclysmic variables (CVs), and symbiotic binaries are known to flare in the radio. RS CVn are binary systems consisting of a late-type giant or sub-giant star with a late-type main-sequence star companion (e.g. Hall 1976; Craig et al. 1997; García-Sánchez, Paredes & Ribó 2003). RS CVn are chromospherically active and the giant or sub-giant rotates quasi-synchronously with the orbital period. Periods for RS CVn are typically 1–20 d, and radio flares on RS CVn systems have been observed to last up to a few days (e.g. Walter et al. 1987; Trigilio, Umana & Migenes 1993). RS CVn emit in both the radio and X-ray while in quiescence (e.g. Gunn 1996). CVs are binary systems with a white dwarf primary accreting matter from Roche lobe overflow of the secondary star, usually a main-sequence star (e.g. Coppejans et al. 2016). Dwarf novae from magnetic CVs have been observed to exhibit radio outbursts that can last for weeks, with rapid radio flaring on time-scales less than an hour (Mooley et al. 2017). Symbiotic binaries also have a white dwarf primary, but the companion is a red giant star and the orbit is wide. In these systems, mass is accreted on to the white dwarf via stellar winds (O’Brien et al. 2015). Radio variability over time-scales of a few hours have been detected on symbiotic binaries, for example RX Puppis (Seaquist 1977). AR Scorpii is another stellar binary that is observed in the radio, it consists of a white dwarf primary and an M-dwarf companion. AR Scorpii has an orbital period of 3.56 h, is observed to pulsate in the optical, radio and X-ray with a period of 1.97 min (Marsh et al. 2016; Takata et al. 2018), and is highly polarized (e.g. Buckley et al. 2017). Radio flaring stellar systems vary on a variety of time-scales, making it difficult to detect when these systems are in outburst (e.g. Osten & Bastian 2008). This means that wide-field monitoring is an important method for discovering and investigating these sources in the radio.","Citation Text":["O’Brien et al. 2015"],"Citation Start End":[[1762,1781]]} {"Identifier":"2020MNRAS.494.5008W__Kocifaj_et_al._2019_Instance_1","Paragraph":"It has been shown by Kocifaj et al. (2019) that night-sky luminance due to a ground-based light source (city or town) can be approximated for intermediate and\/or long distances $D$ by the formula\n(1)$$\\begin{eqnarray*}\r\nJ \\left( z \\right) = {I_0}\\ \\frac{9}{{32\\pi }}\\frac{{\\tilde{\\tau }{\\mathrm{ e}^{ - D\\tilde{\\tau }\/\\left( {3\\tilde{H}} \\right)}}}}{{\\mu \\tilde{H}D}}\\left\\{ {Ci\\left( {aD} \\right)\\sin\\left( {aD} \\right) + \\left[ {\\frac{\\pi }{2} - Si\\left( {aD} \\right)} \\right]\\cos\\left( {aD} \\right)} \\right\\},\r\n\\end{eqnarray*}$$where $z$ is the observational zenith angle, $\\mu = \\cos( z )$, ${I_0}$ the luminance of a city normalized to its area, i.e. the city interpreted as a point light source (${I_0}$ is measured in cd or lm sr−1). The functions $Si( x )$ and $Ci( x )$ introduced above are sine and cosine integrals, respectively (Press et al. 2007).The argument $x$ is the product of distance $\\ D$ and parameter $a$, with\n(2)$$\\begin{eqnarray*}\r\na\\ = \\frac{{\\tilde{\\tau }}}{{\\tilde{H}}}\\ \\left( {1 + \\frac{{{{\\tilde{\\mu }}_0}}}{\\mu }} \\right),\r\n\\end{eqnarray*}$$where ${\\mu _0}$ is the mean effective cosine of the emission angle (see section 2 of Kocifaj et al. 2019) and $\\tilde{H}\\ $ is the altitude up to which a homogeneous atmosphere would extend. Here we assume that $\\tilde{H}\\ $ is composed of the weighed contributions of molecular and aerosol constituents, i.e.\n(3)$$\\begin{eqnarray*}\r\n\\tilde{H} = \\frac{{{H_\\mathrm{ R}}{{\\tilde{\\tau }}_\\mathrm{ R}} + {H_\\mathrm{ a}}{{\\tilde{\\tau }}_\\mathrm{ a}}}}{{{{\\tilde{\\tau }}_\\mathrm{ R}} + {{\\tilde{\\tau }}_\\mathrm{ a}}}},\r\n\\end{eqnarray*}$$where ${\\tilde{\\tau }_\\mathrm{ R}}$ and ${\\tilde{\\tau }_\\mathrm{ a}}$ are the Rayleigh and aerosol components of the total optical depth of a cloudless atmosphere except for ozone or water-vapour absorption bands, i.e. $\\tilde{\\tau } = {\\tilde{\\tau }_\\mathrm{ R}} + {\\tilde{\\tau }_\\mathrm{ a}}$ (Utrillas et al. 2000). Here, ${H_\\mathrm{ R}}$ and ${H_\\mathrm{ a}}$ are the Rayleigh and aerosol components of the atmospheric scaleheights. Aerosol scaleheight typically ranges from 1–3 km (Wu et al. 2011), while ${H_\\mathrm{ R}}$ = 8 km is a commonly accepted value in many studies (see e.g. Waquet et al. 2009). The emission function for a city, i.e. the luminous intensity emitted by that city, is generally unknown, so an isotropic-like radiator appears to be a useful zero-order approximation, resulting in the following formula:\n(4)$$\\begin{eqnarray*}\r\nJ \\left( z \\right) = {W_0}\\ \\frac{9}{{64{\\pi ^2}}}\\frac{{\\tilde{\\tau }{\\mathrm{ e}^{ - D\\tilde{\\tau }\/\\left( {3\\tilde{H}} \\right)}}}}{{\\mu \\tilde{H}D}}\\left\\{ {Ci\\left( {aD} \\right)\\sin\\left( {aD} \\right) + \\left[ {\\frac{\\pi }{2} - Si\\left( {aD} \\right)} \\right]\\cos\\left( {aD} \\right)} \\right\\},\r\n\\end{eqnarray*}$$where ${W_0}$ (lm) is the total amount of lumens directed above the horizontal; consequently, it is obtained as a superposition of both direct emission upwards and isotropic reflection from the ground. If the entirety of light approaching the sky is due only to diffuse reflection from the ground, then ${W_0} = G \\cdot W_0^{\\rm installed}$, where $G$ is the diffuse reflectance and $W_0^{\\rm installed}$ is the total lumen output from all light sources in the city.","Citation Text":["Kocifaj et al. (2019)"],"Citation Start End":[[21,42]]} {"Identifier":"2020MNRAS.494.5008W__Kocifaj_et_al._2019_Instance_2","Paragraph":"It has been shown by Kocifaj et al. (2019) that night-sky luminance due to a ground-based light source (city or town) can be approximated for intermediate and\/or long distances $D$ by the formula\n(1)$$\\begin{eqnarray*}\r\nJ \\left( z \\right) = {I_0}\\ \\frac{9}{{32\\pi }}\\frac{{\\tilde{\\tau }{\\mathrm{ e}^{ - D\\tilde{\\tau }\/\\left( {3\\tilde{H}} \\right)}}}}{{\\mu \\tilde{H}D}}\\left\\{ {Ci\\left( {aD} \\right)\\sin\\left( {aD} \\right) + \\left[ {\\frac{\\pi }{2} - Si\\left( {aD} \\right)} \\right]\\cos\\left( {aD} \\right)} \\right\\},\r\n\\end{eqnarray*}$$where $z$ is the observational zenith angle, $\\mu = \\cos( z )$, ${I_0}$ the luminance of a city normalized to its area, i.e. the city interpreted as a point light source (${I_0}$ is measured in cd or lm sr−1). The functions $Si( x )$ and $Ci( x )$ introduced above are sine and cosine integrals, respectively (Press et al. 2007).The argument $x$ is the product of distance $\\ D$ and parameter $a$, with\n(2)$$\\begin{eqnarray*}\r\na\\ = \\frac{{\\tilde{\\tau }}}{{\\tilde{H}}}\\ \\left( {1 + \\frac{{{{\\tilde{\\mu }}_0}}}{\\mu }} \\right),\r\n\\end{eqnarray*}$$where ${\\mu _0}$ is the mean effective cosine of the emission angle (see section 2 of Kocifaj et al. 2019) and $\\tilde{H}\\ $ is the altitude up to which a homogeneous atmosphere would extend. Here we assume that $\\tilde{H}\\ $ is composed of the weighed contributions of molecular and aerosol constituents, i.e.\n(3)$$\\begin{eqnarray*}\r\n\\tilde{H} = \\frac{{{H_\\mathrm{ R}}{{\\tilde{\\tau }}_\\mathrm{ R}} + {H_\\mathrm{ a}}{{\\tilde{\\tau }}_\\mathrm{ a}}}}{{{{\\tilde{\\tau }}_\\mathrm{ R}} + {{\\tilde{\\tau }}_\\mathrm{ a}}}},\r\n\\end{eqnarray*}$$where ${\\tilde{\\tau }_\\mathrm{ R}}$ and ${\\tilde{\\tau }_\\mathrm{ a}}$ are the Rayleigh and aerosol components of the total optical depth of a cloudless atmosphere except for ozone or water-vapour absorption bands, i.e. $\\tilde{\\tau } = {\\tilde{\\tau }_\\mathrm{ R}} + {\\tilde{\\tau }_\\mathrm{ a}}$ (Utrillas et al. 2000). Here, ${H_\\mathrm{ R}}$ and ${H_\\mathrm{ a}}$ are the Rayleigh and aerosol components of the atmospheric scaleheights. Aerosol scaleheight typically ranges from 1–3 km (Wu et al. 2011), while ${H_\\mathrm{ R}}$ = 8 km is a commonly accepted value in many studies (see e.g. Waquet et al. 2009). The emission function for a city, i.e. the luminous intensity emitted by that city, is generally unknown, so an isotropic-like radiator appears to be a useful zero-order approximation, resulting in the following formula:\n(4)$$\\begin{eqnarray*}\r\nJ \\left( z \\right) = {W_0}\\ \\frac{9}{{64{\\pi ^2}}}\\frac{{\\tilde{\\tau }{\\mathrm{ e}^{ - D\\tilde{\\tau }\/\\left( {3\\tilde{H}} \\right)}}}}{{\\mu \\tilde{H}D}}\\left\\{ {Ci\\left( {aD} \\right)\\sin\\left( {aD} \\right) + \\left[ {\\frac{\\pi }{2} - Si\\left( {aD} \\right)} \\right]\\cos\\left( {aD} \\right)} \\right\\},\r\n\\end{eqnarray*}$$where ${W_0}$ (lm) is the total amount of lumens directed above the horizontal; consequently, it is obtained as a superposition of both direct emission upwards and isotropic reflection from the ground. If the entirety of light approaching the sky is due only to diffuse reflection from the ground, then ${W_0} = G \\cdot W_0^{\\rm installed}$, where $G$ is the diffuse reflectance and $W_0^{\\rm installed}$ is the total lumen output from all light sources in the city.","Citation Text":["Kocifaj et al. 2019"],"Citation Start End":[[1160,1179]]} {"Identifier":"2015ApJ...806..184D__Gilmore_et_al._2012_Instance_1","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Gilmore et al. 2012"],"Citation Start End":[[1244,1263]]} {"Identifier":"2015ApJ...806..184DAartsen_et_al._(2015)_Instance_1","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Aartsen et al. (2015)"],"Citation Start End":[[518,539]]} {"Identifier":"2015ApJ...806..184DAartsen_et_al._2015_Instance_2","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Aartsen et al. 2015"],"Citation Start End":[[1494,1513]]} {"Identifier":"2015ApJ...806..184DAartsen_et_al._2015_Instance_3","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Aartsen et al. 2015"],"Citation Start End":[[2238,2257]]} {"Identifier":"2015ApJ...806..184DAartsen_et_al._(2014b)_Instance_1","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Aartsen et al. (2014b)"],"Citation Start End":[[405,427]]} {"Identifier":"2015ApJ...806..184DAartsen_et_al._(2014b)_Instance_2","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Aartsen et al. (2014b)"],"Citation Start End":[[713,735]]} {"Identifier":"2015ApJ...806..184DAartsen_et_al._(2014b)_Instance_3","Paragraph":"Assuming that some or the entire detected high-energy neutrino flux originates from cosmic rays accelerated in structure-formation accretion shocks, we find the corresponding gamma-ray flux and determine its contribution to the EGRB for different assumed cosmic-ray spectra and plot these results in Figure 1. Panels on the left show SFCR curves after normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b), and panels on the right use normalization to the latest αν = 2.46 neutrino spectrum from Aartsen et al. (2015). Top panels represent SFCR curves (dot–dashed line) derived for the case of strong shocks, i.e., for cosmic-ray spectral index α = 2.0, which matches that of neutrinos from Aartsen et al. (2014b). Normalization to the αν = 2.0 neutrino spectrum from Aartsen et al. (2014b) yields an upper limit to the SFCR contribution of ≈46% of the EGRB observed by Fermi, which is around the contribution of some of the major components, such as unresolved star-forming galaxies contributing ≲50% (Fields et al. 2010; dashed line), or blazars contributing ≈16% (Abdo et al. 2010a; dotted line). If, for this same SFCR model, the attenuation of highest-energy gamma-ray photons by extragalactic background light (EBL; Gilmore et al. 2012) is included (thin red solid line), we find that this reduces the SFCR contribution to ≲18% of the observed EGRB. The sum of all components is shown with a thick blue solid line. Using the latest neutrino spectrum with αν = 2.46 (Aartsen et al. 2015) as the upper limit constraint, we find that for SFCRs accelerated in strong shocks, i.e., with spectral index α = 2.0, their contribution to the EGRB can be ≈29%, or ≲12% after the EBL attenuation was included. However, SFCRs with such a spectrum cannot explain the entire detected high-energy neutrino flux, and additional sources would be needed. If, on the other hand, SFCRs are assumed to have softer spectra with indices α > 2.0, their resulting fluxes would quickly violate the Fermi EGRB observations. The middle panels of Figure 1 show SFCR gamma-ray fluxes for source spectra α = 2.3, while the bottom panels correspond to α = 2.6. Here we point out that using the latest neutrino fluxes with spectrum αν = 2.46 (Aartsen et al. 2015) is more constraining in the sense that it does not allow for this entire neutrino flux to be of the SFCR origin because the accompanying gamma-ray flux quickly violates the observed EGRB, as we can see in the bottom two panels on the right side of Figure 1. Such a soft neutrino spectrum, together with gamma-ray observations from Fermi, allows for only a small fraction of its flux to be made by SFCRs with hard spectra α ≲ 2.2.","Citation Text":["Aartsen et al. (2014b)"],"Citation Start End":[[790,812]]} {"Identifier":"2022AandA...658A..78S__Green_et_al._(2007)_Instance_1","Paragraph":"The polarized emission of these OH masers was studied several times in the past (e.g., Fish et al. 2005, 2006; Green et al. 2007; Fish & Reid 2007; Fish & Sjouwerman 2010). Fish et al. (2005) detected linearly polarized emission toward 24 OH maser spots at 1.665 GHz with the VLBA (⟨Pl⟩ = 36%). From these detections, they measured a mean polarization angle of + 59°. Under the assumption that the magnetic field is perpendicular to the linear polarization vectors, the magnetic field is orientated on the plane of the sky with an angle \n\n$\\Phi_{\\rm{B}}^{\\rm{1.6~GHz~OH}}={-}31$\n\n\n\nΦ\nB\n\n1.6 GHz OH\n\n=−31\n\n°. From the 6.0 GHz OH masers, the linearly polarized emission was also detected, which led Green et al. (2007) and Fish & Sjouwerman (2010) to measure ⟨Pl⟩ = 13.6% and 19%, respectively. Green et al. (2007) measured a mean linear polarization angle of − 58° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}32$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+32\n\n°) with the Multi-Element Radio Linked Interferometer Network (MERLIN), while Fish & Sjouwerman (2010) measured ⟨χ⟩ = −60° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}30$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+30\n\n°) with a global VLBI network. In addition, from the right circular and left circular polarization spectra of the 1.6 and 6.0 GHz OH masers, it was possible to measure the magnetic field strength. From 11 and 10 Zeeman pairs of 1.7 GHz OH masers, a magnetic field on the plane of the sky B|| = −3.3 mG (Fish et al. 2005) and −4.5 mG (Fish & Reid 2007) was measured, respectively; while from 7, 6, and 11 Zeeman pairs of 6.0 GHz OH masers, B|| = −5.6 mG (Fish et al. 2006), − 3.5 mG (Green et al. 2007), and −4.8 mG (Fish & Sjouwerman 2010) was estimated, respectively. Green et al. (2007) reported a linearly polarized emission from two 6.7 GHz CH3OH maser features with the MERLIN (beam size 43 mas× 43 mas). In particular, for their features C (\n\n$V_{\\rm{lsr}}^{\\rm{C}}={+}14.62$\n\n\n\nV\n\nlsr\nC\n\n=+14.62\n\n km s−1, IC = 53.56 Jy beam−1, \n\n$\\Delta v{_{\\textrm{L}}}^{\\rm{C}}=0.27$\n\n\nΔv{_L}^C=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{C}}=0.2\\%$\n\n\n\nP\nl\nC\n\n=0.2%\n\n) and D (\n\n$V_{\\rm{lsr}}^{\\rm{D}}={+}14.62$\n\n\n\nV\n\nlsr\nD\n\n=+14.62\n\n km s−1, ID = 20.03 Jy beam−1, \n\n$\\Delta v_{\\textrm{L}}^{\\rm{D}}=0.27$\n\n\nΔ\nv\nL\nD\n\n=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{D}}=1.3\\%$\n\n\n\nP\nl\nD\n\n=1.3%\n\n), they measured a linear polarization angle of χC = +20.6° and χD = −76.7°, respectively.Green et al. (2007) also reported the very first Zeeman-splitting measurement for 6.7 GHz CH3OH maser emission using the cross-correlation method (Modjaz et al. 2005); for maser feature D, they measured \n\n$P_{\\rm{V}}^{\\rm{D}}=0.6\\%$\n\n\n\nP\nV\nD\n\n=0.6%\n\n and ΔVZD = 0.9 ± 0.3 m s−1.","Citation Text":["Green et al. 2007"],"Citation Start End":[[111,128]]} {"Identifier":"2022AandA...658A..78S__Green_et_al._(2007)_Instance_2","Paragraph":"The polarized emission of these OH masers was studied several times in the past (e.g., Fish et al. 2005, 2006; Green et al. 2007; Fish & Reid 2007; Fish & Sjouwerman 2010). Fish et al. (2005) detected linearly polarized emission toward 24 OH maser spots at 1.665 GHz with the VLBA (⟨Pl⟩ = 36%). From these detections, they measured a mean polarization angle of + 59°. Under the assumption that the magnetic field is perpendicular to the linear polarization vectors, the magnetic field is orientated on the plane of the sky with an angle \n\n$\\Phi_{\\rm{B}}^{\\rm{1.6~GHz~OH}}={-}31$\n\n\n\nΦ\nB\n\n1.6 GHz OH\n\n=−31\n\n°. From the 6.0 GHz OH masers, the linearly polarized emission was also detected, which led Green et al. (2007) and Fish & Sjouwerman (2010) to measure ⟨Pl⟩ = 13.6% and 19%, respectively. Green et al. (2007) measured a mean linear polarization angle of − 58° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}32$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+32\n\n°) with the Multi-Element Radio Linked Interferometer Network (MERLIN), while Fish & Sjouwerman (2010) measured ⟨χ⟩ = −60° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}30$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+30\n\n°) with a global VLBI network. In addition, from the right circular and left circular polarization spectra of the 1.6 and 6.0 GHz OH masers, it was possible to measure the magnetic field strength. From 11 and 10 Zeeman pairs of 1.7 GHz OH masers, a magnetic field on the plane of the sky B|| = −3.3 mG (Fish et al. 2005) and −4.5 mG (Fish & Reid 2007) was measured, respectively; while from 7, 6, and 11 Zeeman pairs of 6.0 GHz OH masers, B|| = −5.6 mG (Fish et al. 2006), − 3.5 mG (Green et al. 2007), and −4.8 mG (Fish & Sjouwerman 2010) was estimated, respectively. Green et al. (2007) reported a linearly polarized emission from two 6.7 GHz CH3OH maser features with the MERLIN (beam size 43 mas× 43 mas). In particular, for their features C (\n\n$V_{\\rm{lsr}}^{\\rm{C}}={+}14.62$\n\n\n\nV\n\nlsr\nC\n\n=+14.62\n\n km s−1, IC = 53.56 Jy beam−1, \n\n$\\Delta v{_{\\textrm{L}}}^{\\rm{C}}=0.27$\n\n\nΔv{_L}^C=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{C}}=0.2\\%$\n\n\n\nP\nl\nC\n\n=0.2%\n\n) and D (\n\n$V_{\\rm{lsr}}^{\\rm{D}}={+}14.62$\n\n\n\nV\n\nlsr\nD\n\n=+14.62\n\n km s−1, ID = 20.03 Jy beam−1, \n\n$\\Delta v_{\\textrm{L}}^{\\rm{D}}=0.27$\n\n\nΔ\nv\nL\nD\n\n=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{D}}=1.3\\%$\n\n\n\nP\nl\nD\n\n=1.3%\n\n), they measured a linear polarization angle of χC = +20.6° and χD = −76.7°, respectively.Green et al. (2007) also reported the very first Zeeman-splitting measurement for 6.7 GHz CH3OH maser emission using the cross-correlation method (Modjaz et al. 2005); for maser feature D, they measured \n\n$P_{\\rm{V}}^{\\rm{D}}=0.6\\%$\n\n\n\nP\nV\nD\n\n=0.6%\n\n and ΔVZD = 0.9 ± 0.3 m s−1.","Citation Text":["Green et al. (2007)"],"Citation Start End":[[697,716]]} {"Identifier":"2022AandA...658A..78S__Green_et_al._(2007)_Instance_3","Paragraph":"The polarized emission of these OH masers was studied several times in the past (e.g., Fish et al. 2005, 2006; Green et al. 2007; Fish & Reid 2007; Fish & Sjouwerman 2010). Fish et al. (2005) detected linearly polarized emission toward 24 OH maser spots at 1.665 GHz with the VLBA (⟨Pl⟩ = 36%). From these detections, they measured a mean polarization angle of + 59°. Under the assumption that the magnetic field is perpendicular to the linear polarization vectors, the magnetic field is orientated on the plane of the sky with an angle \n\n$\\Phi_{\\rm{B}}^{\\rm{1.6~GHz~OH}}={-}31$\n\n\n\nΦ\nB\n\n1.6 GHz OH\n\n=−31\n\n°. From the 6.0 GHz OH masers, the linearly polarized emission was also detected, which led Green et al. (2007) and Fish & Sjouwerman (2010) to measure ⟨Pl⟩ = 13.6% and 19%, respectively. Green et al. (2007) measured a mean linear polarization angle of − 58° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}32$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+32\n\n°) with the Multi-Element Radio Linked Interferometer Network (MERLIN), while Fish & Sjouwerman (2010) measured ⟨χ⟩ = −60° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}30$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+30\n\n°) with a global VLBI network. In addition, from the right circular and left circular polarization spectra of the 1.6 and 6.0 GHz OH masers, it was possible to measure the magnetic field strength. From 11 and 10 Zeeman pairs of 1.7 GHz OH masers, a magnetic field on the plane of the sky B|| = −3.3 mG (Fish et al. 2005) and −4.5 mG (Fish & Reid 2007) was measured, respectively; while from 7, 6, and 11 Zeeman pairs of 6.0 GHz OH masers, B|| = −5.6 mG (Fish et al. 2006), − 3.5 mG (Green et al. 2007), and −4.8 mG (Fish & Sjouwerman 2010) was estimated, respectively. Green et al. (2007) reported a linearly polarized emission from two 6.7 GHz CH3OH maser features with the MERLIN (beam size 43 mas× 43 mas). In particular, for their features C (\n\n$V_{\\rm{lsr}}^{\\rm{C}}={+}14.62$\n\n\n\nV\n\nlsr\nC\n\n=+14.62\n\n km s−1, IC = 53.56 Jy beam−1, \n\n$\\Delta v{_{\\textrm{L}}}^{\\rm{C}}=0.27$\n\n\nΔv{_L}^C=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{C}}=0.2\\%$\n\n\n\nP\nl\nC\n\n=0.2%\n\n) and D (\n\n$V_{\\rm{lsr}}^{\\rm{D}}={+}14.62$\n\n\n\nV\n\nlsr\nD\n\n=+14.62\n\n km s−1, ID = 20.03 Jy beam−1, \n\n$\\Delta v_{\\textrm{L}}^{\\rm{D}}=0.27$\n\n\nΔ\nv\nL\nD\n\n=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{D}}=1.3\\%$\n\n\n\nP\nl\nD\n\n=1.3%\n\n), they measured a linear polarization angle of χC = +20.6° and χD = −76.7°, respectively.Green et al. (2007) also reported the very first Zeeman-splitting measurement for 6.7 GHz CH3OH maser emission using the cross-correlation method (Modjaz et al. 2005); for maser feature D, they measured \n\n$P_{\\rm{V}}^{\\rm{D}}=0.6\\%$\n\n\n\nP\nV\nD\n\n=0.6%\n\n and ΔVZD = 0.9 ± 0.3 m s−1.","Citation Text":["Green et al. (2007)"],"Citation Start End":[[793,812]]} {"Identifier":"2022AandA...658A..78S__Green_et_al._(2007)_Instance_5","Paragraph":"The polarized emission of these OH masers was studied several times in the past (e.g., Fish et al. 2005, 2006; Green et al. 2007; Fish & Reid 2007; Fish & Sjouwerman 2010). Fish et al. (2005) detected linearly polarized emission toward 24 OH maser spots at 1.665 GHz with the VLBA (⟨Pl⟩ = 36%). From these detections, they measured a mean polarization angle of + 59°. Under the assumption that the magnetic field is perpendicular to the linear polarization vectors, the magnetic field is orientated on the plane of the sky with an angle \n\n$\\Phi_{\\rm{B}}^{\\rm{1.6~GHz~OH}}={-}31$\n\n\n\nΦ\nB\n\n1.6 GHz OH\n\n=−31\n\n°. From the 6.0 GHz OH masers, the linearly polarized emission was also detected, which led Green et al. (2007) and Fish & Sjouwerman (2010) to measure ⟨Pl⟩ = 13.6% and 19%, respectively. Green et al. (2007) measured a mean linear polarization angle of − 58° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}32$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+32\n\n°) with the Multi-Element Radio Linked Interferometer Network (MERLIN), while Fish & Sjouwerman (2010) measured ⟨χ⟩ = −60° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}30$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+30\n\n°) with a global VLBI network. In addition, from the right circular and left circular polarization spectra of the 1.6 and 6.0 GHz OH masers, it was possible to measure the magnetic field strength. From 11 and 10 Zeeman pairs of 1.7 GHz OH masers, a magnetic field on the plane of the sky B|| = −3.3 mG (Fish et al. 2005) and −4.5 mG (Fish & Reid 2007) was measured, respectively; while from 7, 6, and 11 Zeeman pairs of 6.0 GHz OH masers, B|| = −5.6 mG (Fish et al. 2006), − 3.5 mG (Green et al. 2007), and −4.8 mG (Fish & Sjouwerman 2010) was estimated, respectively. Green et al. (2007) reported a linearly polarized emission from two 6.7 GHz CH3OH maser features with the MERLIN (beam size 43 mas× 43 mas). In particular, for their features C (\n\n$V_{\\rm{lsr}}^{\\rm{C}}={+}14.62$\n\n\n\nV\n\nlsr\nC\n\n=+14.62\n\n km s−1, IC = 53.56 Jy beam−1, \n\n$\\Delta v{_{\\textrm{L}}}^{\\rm{C}}=0.27$\n\n\nΔv{_L}^C=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{C}}=0.2\\%$\n\n\n\nP\nl\nC\n\n=0.2%\n\n) and D (\n\n$V_{\\rm{lsr}}^{\\rm{D}}={+}14.62$\n\n\n\nV\n\nlsr\nD\n\n=+14.62\n\n km s−1, ID = 20.03 Jy beam−1, \n\n$\\Delta v_{\\textrm{L}}^{\\rm{D}}=0.27$\n\n\nΔ\nv\nL\nD\n\n=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{D}}=1.3\\%$\n\n\n\nP\nl\nD\n\n=1.3%\n\n), they measured a linear polarization angle of χC = +20.6° and χD = −76.7°, respectively.Green et al. (2007) also reported the very first Zeeman-splitting measurement for 6.7 GHz CH3OH maser emission using the cross-correlation method (Modjaz et al. 2005); for maser feature D, they measured \n\n$P_{\\rm{V}}^{\\rm{D}}=0.6\\%$\n\n\n\nP\nV\nD\n\n=0.6%\n\n and ΔVZD = 0.9 ± 0.3 m s−1.","Citation Text":["Green et al. (2007)"],"Citation Start End":[[1694,1713]]} {"Identifier":"2022AandA...658A..78S__Green_et_al._(2007)_Instance_4","Paragraph":"The polarized emission of these OH masers was studied several times in the past (e.g., Fish et al. 2005, 2006; Green et al. 2007; Fish & Reid 2007; Fish & Sjouwerman 2010). Fish et al. (2005) detected linearly polarized emission toward 24 OH maser spots at 1.665 GHz with the VLBA (⟨Pl⟩ = 36%). From these detections, they measured a mean polarization angle of + 59°. Under the assumption that the magnetic field is perpendicular to the linear polarization vectors, the magnetic field is orientated on the plane of the sky with an angle \n\n$\\Phi_{\\rm{B}}^{\\rm{1.6~GHz~OH}}={-}31$\n\n\n\nΦ\nB\n\n1.6 GHz OH\n\n=−31\n\n°. From the 6.0 GHz OH masers, the linearly polarized emission was also detected, which led Green et al. (2007) and Fish & Sjouwerman (2010) to measure ⟨Pl⟩ = 13.6% and 19%, respectively. Green et al. (2007) measured a mean linear polarization angle of − 58° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}32$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+32\n\n°) with the Multi-Element Radio Linked Interferometer Network (MERLIN), while Fish & Sjouwerman (2010) measured ⟨χ⟩ = −60° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}30$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+30\n\n°) with a global VLBI network. In addition, from the right circular and left circular polarization spectra of the 1.6 and 6.0 GHz OH masers, it was possible to measure the magnetic field strength. From 11 and 10 Zeeman pairs of 1.7 GHz OH masers, a magnetic field on the plane of the sky B|| = −3.3 mG (Fish et al. 2005) and −4.5 mG (Fish & Reid 2007) was measured, respectively; while from 7, 6, and 11 Zeeman pairs of 6.0 GHz OH masers, B|| = −5.6 mG (Fish et al. 2006), − 3.5 mG (Green et al. 2007), and −4.8 mG (Fish & Sjouwerman 2010) was estimated, respectively. Green et al. (2007) reported a linearly polarized emission from two 6.7 GHz CH3OH maser features with the MERLIN (beam size 43 mas× 43 mas). In particular, for their features C (\n\n$V_{\\rm{lsr}}^{\\rm{C}}={+}14.62$\n\n\n\nV\n\nlsr\nC\n\n=+14.62\n\n km s−1, IC = 53.56 Jy beam−1, \n\n$\\Delta v{_{\\textrm{L}}}^{\\rm{C}}=0.27$\n\n\nΔv{_L}^C=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{C}}=0.2\\%$\n\n\n\nP\nl\nC\n\n=0.2%\n\n) and D (\n\n$V_{\\rm{lsr}}^{\\rm{D}}={+}14.62$\n\n\n\nV\n\nlsr\nD\n\n=+14.62\n\n km s−1, ID = 20.03 Jy beam−1, \n\n$\\Delta v_{\\textrm{L}}^{\\rm{D}}=0.27$\n\n\nΔ\nv\nL\nD\n\n=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{D}}=1.3\\%$\n\n\n\nP\nl\nD\n\n=1.3%\n\n), they measured a linear polarization angle of χC = +20.6° and χD = −76.7°, respectively.Green et al. (2007) also reported the very first Zeeman-splitting measurement for 6.7 GHz CH3OH maser emission using the cross-correlation method (Modjaz et al. 2005); for maser feature D, they measured \n\n$P_{\\rm{V}}^{\\rm{D}}=0.6\\%$\n\n\n\nP\nV\nD\n\n=0.6%\n\n and ΔVZD = 0.9 ± 0.3 m s−1.","Citation Text":["Green et al. 2007"],"Citation Start End":[[1608,1625]]} {"Identifier":"2022AandA...658A..78S__Green_et_al._(2007)_Instance_6","Paragraph":"The polarized emission of these OH masers was studied several times in the past (e.g., Fish et al. 2005, 2006; Green et al. 2007; Fish & Reid 2007; Fish & Sjouwerman 2010). Fish et al. (2005) detected linearly polarized emission toward 24 OH maser spots at 1.665 GHz with the VLBA (⟨Pl⟩ = 36%). From these detections, they measured a mean polarization angle of + 59°. Under the assumption that the magnetic field is perpendicular to the linear polarization vectors, the magnetic field is orientated on the plane of the sky with an angle \n\n$\\Phi_{\\rm{B}}^{\\rm{1.6~GHz~OH}}={-}31$\n\n\n\nΦ\nB\n\n1.6 GHz OH\n\n=−31\n\n°. From the 6.0 GHz OH masers, the linearly polarized emission was also detected, which led Green et al. (2007) and Fish & Sjouwerman (2010) to measure ⟨Pl⟩ = 13.6% and 19%, respectively. Green et al. (2007) measured a mean linear polarization angle of − 58° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}32$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+32\n\n°) with the Multi-Element Radio Linked Interferometer Network (MERLIN), while Fish & Sjouwerman (2010) measured ⟨χ⟩ = −60° (\n\n$\\Phi_{\\rm{B}}^{\\rm{6.0~GHz~OH}}={+}30$\n\n\n\nΦ\nB\n\n6.0 GHz OH\n\n=+30\n\n°) with a global VLBI network. In addition, from the right circular and left circular polarization spectra of the 1.6 and 6.0 GHz OH masers, it was possible to measure the magnetic field strength. From 11 and 10 Zeeman pairs of 1.7 GHz OH masers, a magnetic field on the plane of the sky B|| = −3.3 mG (Fish et al. 2005) and −4.5 mG (Fish & Reid 2007) was measured, respectively; while from 7, 6, and 11 Zeeman pairs of 6.0 GHz OH masers, B|| = −5.6 mG (Fish et al. 2006), − 3.5 mG (Green et al. 2007), and −4.8 mG (Fish & Sjouwerman 2010) was estimated, respectively. Green et al. (2007) reported a linearly polarized emission from two 6.7 GHz CH3OH maser features with the MERLIN (beam size 43 mas× 43 mas). In particular, for their features C (\n\n$V_{\\rm{lsr}}^{\\rm{C}}={+}14.62$\n\n\n\nV\n\nlsr\nC\n\n=+14.62\n\n km s−1, IC = 53.56 Jy beam−1, \n\n$\\Delta v{_{\\textrm{L}}}^{\\rm{C}}=0.27$\n\n\nΔv{_L}^C=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{C}}=0.2\\%$\n\n\n\nP\nl\nC\n\n=0.2%\n\n) and D (\n\n$V_{\\rm{lsr}}^{\\rm{D}}={+}14.62$\n\n\n\nV\n\nlsr\nD\n\n=+14.62\n\n km s−1, ID = 20.03 Jy beam−1, \n\n$\\Delta v_{\\textrm{L}}^{\\rm{D}}=0.27$\n\n\nΔ\nv\nL\nD\n\n=0.27\n\n km s−1, \n\n$P_{\\rm{l}}^{\\rm{D}}=1.3\\%$\n\n\n\nP\nl\nD\n\n=1.3%\n\n), they measured a linear polarization angle of χC = +20.6° and χD = −76.7°, respectively.Green et al. (2007) also reported the very first Zeeman-splitting measurement for 6.7 GHz CH3OH maser emission using the cross-correlation method (Modjaz et al. 2005); for maser feature D, they measured \n\n$P_{\\rm{V}}^{\\rm{D}}=0.6\\%$\n\n\n\nP\nV\nD\n\n=0.6%\n\n and ΔVZD = 0.9 ± 0.3 m s−1.","Citation Text":["Green et al. (2007)"],"Citation Start End":[[2376,2395]]} {"Identifier":"2019MNRAS.490.3987W__Rybicki_&_Lightman_1986_Instance_1","Paragraph":"We compute the integrated polarized emission of our radio relic following the formalism of Burn (1966): \n(6)$$\\begin{eqnarray*}\r\nP_{\\mathrm{pol}}(\\lambda ^2) = \\frac{\\sum \\limits _{\\mathrm{los}} P_{\\mathrm{tot}} \\Pi \\exp \\left(2i \\left(\\epsilon _{\\mathrm{int}} + \\mathrm{RM}\\lambda ^2 \\right) \\right) \\mathrm{d}s}{\\sum \\limits _{\\mathrm{los}} P_{\\mathrm{tot}} \\mathrm{d}s},\\end{eqnarray*}$$using the emission per volume in each simulation cell Ptot, the intrinsic degree of polarization Π and the intrinsic angle of polarization ϵint. RMλ2 accounts for Faraday rotation. The intrinsic degree of polarization Π at observing frequency νobs is computed using the parallel and perpendicular components of the radio emission, equations (3) and (4) (e.g. Rybicki & Lightman 1986): \n(7)$$\\begin{eqnarray*}\r\n\\Pi = \\frac{P_{\\parallel }-P_{\\perp }}{P_{\\parallel }+P_{\\perp }}.\\end{eqnarray*}$$The intrinsic angle of polarization, ϵint, is computed with respect to the horizontal axis of the projected maps. Each simulation cell can be considered to be filled with a uniform magnetic field and, in this case, the intrinsic angle of polarization is perpendicular to the direction of the projected magnetic field. If the emission is going through a magnetized medium, the intrinsic angle of polarization is Faraday rotated. In equation (6), RMλ2 determines the amount of Faraday rotation. Here, λ is the wavelength corresponding to the observation frequency and RM is the rotation measure (RM) of the ambient medium. The RM at a distance x from the observer is computed as: \n(8)$$\\begin{eqnarray*}\r\n\\mathrm{RM}= 812 \\int _{0}^x \\frac{n_\\mathrm{e}}{10^{-3} \\ \\mathrm{cm}^{-3}} \\frac{B_{\\mathrm{para}}}{\\mu \\mathrm{G}} \\frac{\\mathrm{d}l}{\\mathrm{kpc}} \\ \\left[\\mathrm{\\frac{rad}{m^2}}\\right].\\end{eqnarray*}$$The integral is taken along the LoS. ne and Bpara are the thermal electron number density and parallel magnetic field component, respectively, along the LoS. Faraday rotation occurs either outside of the emitting region, external Faraday rotation, or inside the source, internal Faraday rotation.","Citation Text":["Rybicki & Lightman 1986"],"Citation Start End":[[749,772]]} {"Identifier":"2017ApJ...839..105W__Koyama_et_al._2007_Instance_1","Paragraph":"Table 1 provides the details of the X-ray observations of Holmberg IX X-1 presented in this work. Our data reduction largely follows the procedures outlined in Walton et al. (2014). The XMM-Newton data for epochs 1 and 2 were re-reduced using SAS v14.0.0 in exactly the same manner as described in our previous work for both the EPIC-pn and EPIC-MOS detectors (Strüder et al. 2001; Turner et al. 2001), using more recent calibration files (up to date as of 2015 July). Our new Suzaku observations (epochs 3–6) were also reduced with HEASOFT v6.18 in the same manner as the epoch 1 data; as before, we only used the XIS detectors (Koyama et al. 2007) given the high-energy NuSTAR coverage. The only major update to our data reduction procedure in comparison to Walton et al. (2014) is for the NuSTAR data. The standard science data (mode 1) were reduced with NUSTARDAS v1.5.1 in the same manner as in that work, again with updated calibration files (NuSTAR CALDB 20150316). However, in order to maximize the signal-to-noise ratio (S\/N), in this work we also make use of the spacecraft science data (mode 6) following the procedure outlined in Walton et al. (2016c; see also the NuSTAR Users Guide11\n\n11\n\nhttp:\/\/heasarc.gsfc.nasa.gov\/docs\/nustar\/analysis\/nustar_swguide.pdf\n\n). In brief, spacecraft science mode refers to data recorded during periods of the observation in which the X-ray source is still visible, but the star tracker on the optics bench cannot return a good aspect solution. During such times, the star trackers on the spacecraft bus are used instead. For these observations, this provides an additional ∼20%–40% good exposure (depending on the observation). The inclusion of the mode 6 data allows us to fit the NuSTAR data for Holmberg IX X-1 from 3 to 40 keV for all epochs. As in Walton et al. (2014), we model the XMM-Newton spectra over the 0.3–10.0 keV range, and the Suzaku data over the 0.6–10.0 keV range for the front-illuminated XIS units (XIS0, XIS3) and the 0.7–9.0 keV range for the back-illuminated XIS1, excluding 1.7–2.1 keV owing to known calibration issues around the instrumental edges.","Citation Text":["Koyama et al. 2007"],"Citation Start End":[[631,649]]} {"Identifier":"2016MNRAS.461..877V__Feroci_et_al._2001_Instance_1","Paragraph":"The shape of the fireball is an open question. Thompson & Duncan (2001) considered spherical or cylindrical structures, but the exact shape trapped in a realistic magnetar field structure, which may sustain local twists, is unclear. Feroci et al. (2001) showed that the time-dependence of the X-ray luminosity Lx(t) for the light curve of the giant flare from SGR 1900+14 on 1998 August 27 was well fit by the following function:\n\n(1)\n\n\\begin{equation}\nL_{\\rm x}(t) = L_{\\rm x}(0)\\left(1 - \\frac{t}{\\tau _\\mathrm{evap}}\\right)^\\chi ,\n\\end{equation}\n\nwhere τevap is an evaporation time-scale. The parameter χ = a\/(1 − a) can be related, in a simple model where the fireball has uniform energy density and surface flux, to the shape of the fireball (Thompson & Duncan 2001). For the 1998 giant flare from SGR 1900+14, the best-fitting value was a = 0.75 (Feroci et al. 2001), while for the 2004 December 27 giant flare of SGR 1806–20, Hurley et al. (2005) found a = 0.6. A homogeneous fireball cannot have a value higher than a = 2\/3, which is also the value for a homogeneous sphere, so these results show that the SGR 1900+14 fireball may have a more complex structure (Thompson & Duncan 2001). In this paper, we choose to model the magnetic field as a pure dipole, which is sufficient to explore the generic character of outflows and fireballs, and their coupling. This choice leads to a torus-shaped fireball, as that is the only shape that can be trapped in the closed field-lines of a dipole field. We use the equations for a dipolar magnetic field in full general relativity given by Wasserman & Shapiro (1983). When considered in two dimensions (as our model geometry has rotational symmetry) the boundary of the fireball lies along a single closed field line, which is determined by a single parameter. We choose to use the diameter of the torus-shaped fireball as this parameter, defined as the equatorial radius of the outermost field line minus the radius of the star. We let the diameter vary between one and one hundred kilometres (∼0.1–10 stellar radii), to cover all possible fireball sizes.","Citation Text":["Feroci et al. (2001)"],"Citation Start End":[[233,253]]} {"Identifier":"2016MNRAS.461..877V__Feroci_et_al._2001_Instance_2","Paragraph":"The shape of the fireball is an open question. Thompson & Duncan (2001) considered spherical or cylindrical structures, but the exact shape trapped in a realistic magnetar field structure, which may sustain local twists, is unclear. Feroci et al. (2001) showed that the time-dependence of the X-ray luminosity Lx(t) for the light curve of the giant flare from SGR 1900+14 on 1998 August 27 was well fit by the following function:\n\n(1)\n\n\\begin{equation}\nL_{\\rm x}(t) = L_{\\rm x}(0)\\left(1 - \\frac{t}{\\tau _\\mathrm{evap}}\\right)^\\chi ,\n\\end{equation}\n\nwhere τevap is an evaporation time-scale. The parameter χ = a\/(1 − a) can be related, in a simple model where the fireball has uniform energy density and surface flux, to the shape of the fireball (Thompson & Duncan 2001). For the 1998 giant flare from SGR 1900+14, the best-fitting value was a = 0.75 (Feroci et al. 2001), while for the 2004 December 27 giant flare of SGR 1806–20, Hurley et al. (2005) found a = 0.6. A homogeneous fireball cannot have a value higher than a = 2\/3, which is also the value for a homogeneous sphere, so these results show that the SGR 1900+14 fireball may have a more complex structure (Thompson & Duncan 2001). In this paper, we choose to model the magnetic field as a pure dipole, which is sufficient to explore the generic character of outflows and fireballs, and their coupling. This choice leads to a torus-shaped fireball, as that is the only shape that can be trapped in the closed field-lines of a dipole field. We use the equations for a dipolar magnetic field in full general relativity given by Wasserman & Shapiro (1983). When considered in two dimensions (as our model geometry has rotational symmetry) the boundary of the fireball lies along a single closed field line, which is determined by a single parameter. We choose to use the diameter of the torus-shaped fireball as this parameter, defined as the equatorial radius of the outermost field line minus the radius of the star. We let the diameter vary between one and one hundred kilometres (∼0.1–10 stellar radii), to cover all possible fireball sizes.","Citation Text":["Feroci et al. 2001"],"Citation Start End":[[853,871]]} {"Identifier":"2022AandARv..30....6M__Condon_1992_Instance_1","Paragraph":"Star-forming galaxies 'At all the (relatively low, z≲1\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$z\\lesssim 1$$\\end{document}) redshifts probed by present facilities, radio-emitting star-forming galaxies appear in all respect identical to star-forming galaxies selected at any other wavelength, with spectral types ranging from spirals to irregulars and dwarfs. Although only ≲10-4\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$\\lesssim 10^{-4}$$\\end{document} of the bolometric luminosity produced by a non-AGN powered galaxy is radiated at radio wavelengths (Condon 1992), the importance of radio selection for star-forming galaxies relies on the fact that it can provide estimates of the star-formation activity of such sources in a way which is unaffected by the presence of dust up to the earliest epochs. To do that, a solid calibration of the relation between radio luminosity and infrared luminosity (or alternatively SFR) is mandatory. This is why a lot of effort has been put in the recent years to provide calibrations as precise as possible at all redshifts and for all galaxy types. From an observational point of view, it has been found at least in the local universe that radio and infrared luminosities show an incredibly tight, approximately linear, correlation over more than five orders of magnitude in infrared luminosity (e.g., Helou et al. 1985; De Jong et al. 1985; Condon 1992; Yun et al. 2001), irrespective of galaxy type and level of star-forming activity, as long as the galaxy hosts episodes of star-formation. This relation, originally found at 1.4 GHz, has also been observed to hold at different frequencies (e.g., Delhaize et al. 2017; Gürkan et al. 2018). The theoretical reasons behind it are still not fully understood, as many factors involved in the process of shaping a galaxy should intervene to produce at least some modifications which are not (yet) clearly visible in the available data.","Citation Text":["Condon 1992","Condon 1992"],"Citation Start End":[[1002,1013],[1830,1841]]} {"Identifier":"2020ApJ...896...23W__Bolton_et_al._2011_Instance_1","Paragraph":"Observations of the Lyman series forests in z ≳ 6 quasars indicate that the IGM is already highly ionized by z ∼ 6 (e.g., Fan et al. 2006; Bosman et al. 2018; Eilers et al. 2018, 2019; Yang et al. 2020), although the final completion of reionization might extend down to z ∼ 5.5 (e.g., Becker et al. 2015; Davies et al. 2018a; Kulkarni et al. 2019; Keating et al. 2020; Nasir & D’Aloisio 2020). However, the Lyman series forests are very sensitive to neutral hydrogen and saturate even at low IGM neutral fraction (i.e., \n\n\n\n\n\n). On the other hand, if the neutral fraction is of order unity, one would expect to see appreciable absorption redward of the wavelength of the Lyα emission line, resulting in a damping wing profile (e.g., Miralda-Escudé 1998) due to significant optical depth on the Lorentzian wing of the Lyα absorption. The first quasar with a damping wing detection is ULAS J1120+0641 (Mortlock et al. 2011) at z = 7.09, although different analyses yielded different constraints on \n\n\n\n\n\n (Bolton et al. 2011; Mortlock et al. 2011; Bosman & Becker 2015; Greig et al. 2017; Davies et al. 2018b), ranging from \n\n\n\n\n\n to \n\n\n\n\n\n at z ∼ 7.1. Recently, the spectrum of quasar ULAS J1342+0928 (Bañados et al. 2018) at z = 7.54 shows a robust detection of the damping wing signal (Bañados et al. 2018; Davies et al. 2018b; Greig et al. 2019; Ďurovčíková et al. 2020), yielding \n\n\n\n\n\n at z ∼ 7.5. Compared to other probes of reionization history, such as cosmic microwave background (CMB) polarization (Planck Collaboration et al. 2018) and Lyα emission line visibility in high-redshift galaxies (e.g., Ouchi et al. 2010; Mason et al. 2018), a main advantage of IGM damping wing measurement is that it can be applied to individual quasar sight lines, thereby constraining not only the average neutral fraction, but also its scatter in different regions of the IGM. However, the damping wing experiment is only feasible at very high redshifts where the IGM is relatively neutral, and current damping wing analyses have been limited to these two sight lines due to the lack of bright quasars at z ≳ 7. Thus, it is crucial to investigate the damping wing experiment along more z > 7 quasar sight lines.","Citation Text":["Bolton et al. 2011"],"Citation Start End":[[1005,1023]]} {"Identifier":"2020ApJ...897...38D__Cox_1980_Instance_1","Paragraph":"The linearized equation of motion (see derivation of Equation (A12)) for the unmagnetized case is given by (also refer to Christensen-Dalsgaard 2003):\n9\n\n\n\n\n\nwhere cs(r), ρ0(r), and g(r) are the sound speed, density, and gravity (directed radially inward), respectively, and \n\n\n\n\n\n denotes the covariant spatial derivative operator. For all ensuing calculations and derivations, we write Equation (9) in the form \n\n\n\n\n\n, where the magnetically unperturbed wave operator \n\n\n\n\n\n is self-adjoint (Goedbloed & Poedts 2004). To solve for the eigenmodes of the unperturbed model S, the boundary conditions employed are: (a) \n\n\n\n\n\n and the Eulerian pressure perturbation at r = 0 are finite, and (b) the Lagrangian pressure perturbation at r = R⊙ vanishes (see Section 17.6 in Cox 1980). As already mentioned earlier, the Cowling approximation is used, and hence, the gravitational Poisson equation is not needed while finding the eigenmodes. We suppress the subscript “0” in the unperturbed eigenfunctions \n\n\n\n\n\n and eigenfrequencies ωk,0 for the rest of this paper. Unless specified otherwise, any instance of ωk or \n\n\n\n\n\n should be assumed to imply eigenfrequencies and eigenfunctions of Equation (9), respectively. The Sun is treated as a fluid body with a vanishing shear modulus and, hence, is unable to sustain shear waves (although the presence of magnetic fields complicates this assumption). Thus, the eigenfunctions of the background model contain no toroidal components (see Chapter 8 of Dahlen & Tromp 1998), rendering them purely spheroidal. We write the displacement field \n\n\n\n\n\n in the basis of vector spherical harmonics (and thereafter GSH) as follows:\n10\n\n\n\n\n\n\n\n11\n\n\n\n\n\nHere, \n\n\n\n\n\n denote spherical polar coordinates, with basis vectors \n\n\n\n\n\n and \n\n\n\n\n\n where n is the radial order, ℓ is the angular degree, and m is the azimuthal order. The dimensionless lateral covariant derivative operator is denoted by \n\n\n\n\n\n. The basis vectors in spherical polar coordinates are related to those in the GSH basis via\n12\n\n\n\n\n\n\n","Citation Text":["Cox 1980"],"Citation Start End":[[770,778]]} {"Identifier":"2018AandA...613L...1D__Coulter_et_al._2017_Instance_1","Paragraph":"A gravitational wave (GW) event originated by the merger of a binary neutron star (BNS) system was detected for the first time by aLIGO\/Virgo (GW 170817; Abbott et al. 2017a), and was found to be associated to the weak short gamma-ray burst (GRB) GRB 170817A detected by the Fermi and INTEGRAL satellites (Goldstein et al. 2017; Savchenko et al. 2017), marking the dawn of multi-messenger astronomy (Abbott et al. 2017b). The proximity of the event ~41 Mpc; Hjorth et al. 2017, Cantiello et al. 2018) and the relative accuracy of the localisation (~30 deg2, thanks to the joint LIGO and Virgo operation) led to a rapid (Δt 11 h) identification of a relatively bright optical electromagnetic counterpart (EM), named AT2017gfo, in the galaxy NGC 4993 (Arcavi et al. 2017; Coulter et al. 2017; Lipunov et al. 2017; Melandri et al. 2017; Tanvir et al. 2017; Soares-Santos et al. 2017; Valenti et al. 2017). The analysis and modelling of the spectral characteristics of this source, together with their evolution with time, resulted in a good match with the expectations for a “kilonova” (i.e. the emission due to radioactive decay of heavy nuclei produced through rapid neutron capture; Li & Paczyński 1998), providing the first compelling observational evidence for the existence of such elusive transient sources (Cowperthwaite et al. 2017; Drout et al. 2017; Evans et al. 2017; Kasliwal et al. 2017; Nicholl et al. 2017; Pian et al. 2017; Smartt et al. 2017; Villar et al. 2017). While the bright kilonova associated to GW 170817 has been widely studied and its main properties relatively well determined, the observations of the short GRB 170817A are more challenging for the current theoretical frameworks. Indeed, the properties of this short GRB appear puzzling in the context of observations collected over the past decades (Berger 2014; D’Avanzo 2015; Ghirlanda et al. 2015). The prompt γ-ray luminosity was significantly fainter (by a factor ~2500) than typical short bursts (see, e.g. D’Avanzo et al. 2014). A faint afterglow was detected in the X-ray and radio bands only at relatively late times (starting from ~9 and 16 d after the GW\/GRB trigger, respectively; Alexander et al. 2017; Haggard et al. 2017; Hallinan et al. 2017; Margutti et al. 2017; Troja et al. 2017a), while earlier observations provided only upper limits in these bands (Evans et al. 2017; Hallinan et al. 2017).","Citation Text":["Coulter et al. 2017"],"Citation Start End":[[771,790]]} {"Identifier":"2019MNRAS.487..595H__Houdek_&_Dupret_2015_Instance_1","Paragraph":"Gough’s (1977a) concept of averaging over convective eddies is based on Spiegel’s (1963) finding that the linearized equations of motions for determining the convective growth rate σ of a convective eddy, i.e. the rate with which the convective fluctuations grow with time, satisfy a variational equation for σ, if the locally defined superadiabatic temperature gradient β(r0) is replaced by the averaged, i.e. non-local, value (Gough 1977a,b)\n(2)\r\n\\begin{eqnarray*}\r\n{\\cal B}(r)=\\frac{2}{\\ell }\\int \\beta (r_0)\\cos ^2\\left[\\pi (r_0-r)\/\\ell \\right]\\, {\\rm d}r_0\\, .\r\n\\end{eqnarray*}\r\nIn expression (2), the averaging is obtained by taking account of contributions from convective eddies centred at r0 and the range of integration is the vertical extent ℓ, which scales with the local pressure scale height. Based on Spiegel’s finding on the convective growth rate, Gough (1977a) suggested similar expressions for the averaged, non-local, convective heat, ${\\cal {F_{\\mathrm{c}}}}$, and momentum, $\\mathcal {P}_{\\rm t}$, fluxes, with β(r0) in equation (2) being replaced by the locally computed convective fluxes Fc(r0) and pt(r0), respectively. This would, however, lead to a system of integro-differential equations for the stellar structure, which would be difficult to solve numerically. Gough (1977a) suggested therefore to approximate the kernel ${\\cal K}:=2\\cos ^2[\\pi (r_0-r)\/\\ell ]$ in equation (2) by the expression ${\\cal K}\\simeq a\\exp (-a|r_0-r|\/\\ell)\/2$, and setting the integration limits formally to ±∞, which leads to an integral expression that represents the solution to the second-order differential equation\n(3)\r\n\\begin{eqnarray*}\r\n\\frac{{\\rm d}^2{\\cal {F_{\\mathrm{c}}}}}{{\\rm d}\\ln p^2}=\\frac{a^2}{\\alpha ^2}\\left({\\cal {F_{\\mathrm{c}}}}-{F_{\\mathrm{c}}}\\right)\\,\r\n\\end{eqnarray*}\r\n(Gough 1977a; Balmforth 1992a; Houdek & Dupret 2015) for the non-local convective heat flux, ${\\cal {F_{\\mathrm{c}}}}$, for example, where ln p (p is total pressure) is now the new independent depth variable (as implemented in the calculations), α ≔ −ℓdln p\/dr is the mixing-length parameter, and a is another dimensionless, non-local, parameter. Similar expressions are obtained for the averaged, non-local, superadiabatic temperature gradient, $\\cal B$, and turbulent pressure, $\\cal P_{\\mathrm{t}}$, introducing the remaining non-local (dimensionless) parameters b and c, respectively. These non-local parameters control the spatial coherence of the ensemble of eddies contributing to the total heat (a) and momentum (c) fluxes, and the degree to which the turbulent fluxes are coupled to the local stratification (b). Roughly speaking, the parameters a, b, and c control the degree of ‘non-locality’ of convection; low values imply highly non-local solutions, and in the limit a, b, c → ∞ the system of equations formally reduces to the local formulation (except near the boundaries of convection zones, where the local equations are singular). Theoretical values for the dimensionless, non-local, parameters a, b, and c can be obtained by demanding that the terms in a Taylor expansion about r of the exact, 2cos 2[π(r0 − r)\/ℓ], and approximate, aexp (− a|r0 − r|\/ℓ)\/2, kernels differ only at fourth order, resulting in a theoretical estimate for a ≃ 7.8 (Gough 1977a). The standard mixing-length assumption of assigning a unique scale to turbulent eddies at any given location can, however, cause too much smoothing, leading to larger values for a, b, or c (Houdek & Gough 2002). Therefore, values for a, b, and c, which typically differ, need to be determined from calibration in a similar way as it is common for the mixing-length parameter, α, in stellar evolutionary theory.1It should be mentioned that our adopted non-local convection formulation does not treat the overshoot regions correctly, where the non-local enthalpy flux, $\\cal {F_{\\mathrm{c}}}$, remains positive although it should be negative. The overshoot regions may therefore not be suitable for calibrating the non-local parameters to 3D simulation results (see also discussion in Section 5.2). The effect of such positive $\\cal {F_{\\mathrm{c}}}$ values in the overshoot regions on the damping rates and eigenfrequencies is, however, negligible.","Citation Text":["Houdek & Dupret 2015"],"Citation Start End":[[1834,1854]]} {"Identifier":"2018MNRAS.480L..23R__Romeo_&_Falstad_2013_Instance_1","Paragraph":"To explore the link between angular momentum and local gravitational instability in nearby star-forming spirals, we need a reliable disc instability diagnostic. Contrary to what is commonly assumed, the gas Toomre parameter is not a reliable diagnostic: stars, and not molecular or atomic gas, are the primary driver of disc instabilities in spiral galaxies, at least at the spatial resolution of current extragalactic surveys (Romeo & Mogotsi 2017). This is confirmed by other investigations (Marchuk 2018; Marchuk & Sotnikova 2018; Mogotsi & Romeo 2018), and is true even for a powerful starburst+Seyfert galaxy like NGC 1068 (Romeo & Fathi 2016). The stellar Toomre parameter is a more reliable diagnostic, but it does not include the stabilizing effect of disc thickness, which is important and should be taken into account (Romeo & Falstad 2013). The simplest diagnostic that does this accurately is the Romeo–Falstad $\\mathcal {Q}_{N}$ stability parameter for one-component (N = 1) stellar (⋆) discs, which we consider as a function of galactocentric distance R: \n(1)\r\n\\begin{eqnarray*}\r\n\\mathcal {Q}_{\\star }(R)= Q_{\\star }(R)\\, T_{\\star }\\, ,\r\n\\end{eqnarray*}\r\nwhere Q⋆ = κσ⋆\/πGΣ⋆ is the stellar Toomre parameter (σ denotes the radial velocity dispersion), and T⋆ is a factor that encapsulates the stabilizing effect of disc thickness for the whole range of velocity dispersion anisotropy (σ$z$\/σR) observed in galactic discs: \n(2)\r\n\\begin{eqnarray*}\r\nT_{\\star }= \\left\\lbrace \\begin{array}{ll}\\displaystyle 1+0.6\\left(\\frac{\\sigma _{z}}{\\sigma _{R}}\\right)_{\\star }^{2} &\\quad \\text{if }0\\le (\\sigma _{z}\/\\sigma _{R})_{\\star }\\le 0.5\\, , \\\\\r\n{\\displaystyle 0.8+0.7\\left(\\frac{\\sigma _{z}}{\\sigma _{R}}\\right)_{\\star }} &\\quad \\text{if }0.5\\le (\\sigma _{z}\/\\sigma _{R})_{\\star }\\le 1\\, . \\end{array} \\right.\r\n\\end{eqnarray*}\r\nObservations do not yet constrain the radial variation of (σ$z$\/σR)⋆, hence that of T⋆ (Gerssen & Shapiro Griffin 2012; Marchuk & Sotnikova 2017; Pinna et al. 2018).","Citation Text":["Romeo & Falstad 2013"],"Citation Start End":[[829,849]]} {"Identifier":"2015ApJ...811..132M__Veilleux_et_al._2005_Instance_1","Paragraph":"One of the important findings of the COS-Halos survey is that \n\n\n\n\n\n is omnipresent in the halos of SF galaxies which harbor a major reservoir of galactic metals (i.e., Tumlinson et al. 2011a). Outflows from the SF galaxies are thought to be the origin of highly ionized oxygen in the CGM. However, the outflows need not be active at the time of observations. Active outflows that are detected primarily via low-ions (e.g., \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n) absorption in the spectra of host-galaxies (i.e., the “down-the-barrel” outflows) are also found to be ubiquitous at both high and low redshifts (Shapley et al. 2003; Martin 2005; Rupke et al. 2005; Veilleux et al. 2005; Rubin et al. 2010, 2014). Despite the ubiquity of winds, several basic questions that are key to quantifying galaxy feedback remain unanswered. How far do they propagate? What is the baryon mass that are processed through them? What is the mass-flow rate through winds? What are the mass loading factors and kinetic power of the winds? To what degree are metals processed through them? This is essentially because the location of the outflow with respect to host-galaxy is an unknown in “down-the-barrel” outflows. Galaxy outflow probed by a background QSO has the advantage of having the minimum distance between host-galaxy and outflowing material. For example, by analyzing a post-starburst outflow from a galaxy at \n\n\n\n\n\n detected in the spectra of QSO PG 1206+459 at an impact parameter of ∼68 kpc, Tripp et al. (2011) have shown that the entrained gas mass could be as large as ∼ few \n\n\n\n\n\n Numerous strong and large velocity spread (\n\n\n\n\n\n km s−1) metal absorption lines along with solar to super-solar metallicities in different absorption components suggest that the absorber is tracing an active outflow. Such wide velocity spread \n\n\n\n\n\n absorbers at low-z are also reported by Tumlinson et al. (2011b) and Muzahid (2014). In both these cases metallicity of the \n\n\n\n\n\n bearing gas is low (e.g., \n\n\n\n\n\n) which suggest that \n\n\n\n\n\n is probably tracing an “ancient outflow” (Ford et al. 2014) rather than an active wind. Interestingly, strong \n\n\n\n\n\n is detected in PG 1206+459 which is not present in the latter two systems. We note that the location of the absorbing gas with respect to the host-galaxy’s projected major and minor axes are not known for any of these strong \n\n\n\n\n\n absorbers.","Citation Text":["Veilleux et al. 2005"],"Citation Start End":[[647,667]]} {"Identifier":"2022ApJ...934...66S__Tinsley_1980_Instance_1","Paragraph":"Accreting supermassive BHs can have a profound impact on the evolution of the host galaxies (see review by Alexander & Hickox 2012), as testified by the observed tight relationships between the relic BH masses and the physical properties of the hosts, most noticeably the stellar mass or velocity dispersion of the bulge component (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Gebhardt et al. 2000; Tremaine et al. 2002; Kormendy & Ho 2013; McConnell & Ma 2013; Reines & Volonteri 2015; Shankar et al. 2016, 2020a; Sahu et al. 2019; Zhu et al. 2021). These suggest that (apart from short-time stochastic fluctuations) the BH and the bulge stellar mass must have coevolved over comparable timescales, possibly determined by the energy feedback from the BH itself on the gas\/dust content of the host (see Tinsley 1980; Silk & Rees 1998; Fabian 1999; King 2005; Lapi et al. 2006, 2014, 2018; for a review, see King & Pounds 2015). In fact, targeted X-ray observations in the high-redshift star-forming progenitors of local massive galaxies have started to reveal the early growth of a dust-enshrouded (super)massive BH in their nuclear regions (e.g., Mullaney et al. 2012; Page et al. 2012; Delvecchio et al. 2014; Rodighiero et al. 2015, 2019; Fiore et al. 2017; Stanley et al. 2015, 2017; Massardi et al. 2018; Combes et al. 2019; D’Amato et al. 2020) before it attains a high enough mass and power to manifest as a bright AGN and eventually reduce\/quench star formation and partly evacuate gas and dust from the host (e.g., Granato et al. 2001, 2004; Lapi et al. 2011,2014, 2018). Another, albeit more indirect, indication of coevolution for the bulk of the BH and the host stellar mass comes from the similarity between the activity timescales of the central BH to the transition timescale of (green valley) galaxies from the blue cloud to the red sequence (see Wang et al. 2017; Lin et al. 2021, 2022; this is true apart from rejuvenations at late cosmic times; see Martin-Navarro et al. 2022).","Citation Text":["Tinsley 1980"],"Citation Start End":[[813,825]]} {"Identifier":"2022ApJ...934...66SAlexander_&_Hickox_2012_Instance_1","Paragraph":"Accreting supermassive BHs can have a profound impact on the evolution of the host galaxies (see review by Alexander & Hickox 2012), as testified by the observed tight relationships between the relic BH masses and the physical properties of the hosts, most noticeably the stellar mass or velocity dispersion of the bulge component (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Gebhardt et al. 2000; Tremaine et al. 2002; Kormendy & Ho 2013; McConnell & Ma 2013; Reines & Volonteri 2015; Shankar et al. 2016, 2020a; Sahu et al. 2019; Zhu et al. 2021). These suggest that (apart from short-time stochastic fluctuations) the BH and the bulge stellar mass must have coevolved over comparable timescales, possibly determined by the energy feedback from the BH itself on the gas\/dust content of the host (see Tinsley 1980; Silk & Rees 1998; Fabian 1999; King 2005; Lapi et al. 2006, 2014, 2018; for a review, see King & Pounds 2015). In fact, targeted X-ray observations in the high-redshift star-forming progenitors of local massive galaxies have started to reveal the early growth of a dust-enshrouded (super)massive BH in their nuclear regions (e.g., Mullaney et al. 2012; Page et al. 2012; Delvecchio et al. 2014; Rodighiero et al. 2015, 2019; Fiore et al. 2017; Stanley et al. 2015, 2017; Massardi et al. 2018; Combes et al. 2019; D’Amato et al. 2020) before it attains a high enough mass and power to manifest as a bright AGN and eventually reduce\/quench star formation and partly evacuate gas and dust from the host (e.g., Granato et al. 2001, 2004; Lapi et al. 2011,2014, 2018). Another, albeit more indirect, indication of coevolution for the bulk of the BH and the host stellar mass comes from the similarity between the activity timescales of the central BH to the transition timescale of (green valley) galaxies from the blue cloud to the red sequence (see Wang et al. 2017; Lin et al. 2021, 2022; this is true apart from rejuvenations at late cosmic times; see Martin-Navarro et al. 2022).","Citation Text":["Alexander & Hickox 2012"],"Citation Start End":[[107,130]]} {"Identifier":"2022ApJ...934...66SKormendy_&_Ho_2013___Mullaney_et_al._2012_Instance_1","Paragraph":"Accreting supermassive BHs can have a profound impact on the evolution of the host galaxies (see review by Alexander & Hickox 2012), as testified by the observed tight relationships between the relic BH masses and the physical properties of the hosts, most noticeably the stellar mass or velocity dispersion of the bulge component (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Gebhardt et al. 2000; Tremaine et al. 2002; Kormendy & Ho 2013; McConnell & Ma 2013; Reines & Volonteri 2015; Shankar et al. 2016, 2020a; Sahu et al. 2019; Zhu et al. 2021). These suggest that (apart from short-time stochastic fluctuations) the BH and the bulge stellar mass must have coevolved over comparable timescales, possibly determined by the energy feedback from the BH itself on the gas\/dust content of the host (see Tinsley 1980; Silk & Rees 1998; Fabian 1999; King 2005; Lapi et al. 2006, 2014, 2018; for a review, see King & Pounds 2015). In fact, targeted X-ray observations in the high-redshift star-forming progenitors of local massive galaxies have started to reveal the early growth of a dust-enshrouded (super)massive BH in their nuclear regions (e.g., Mullaney et al. 2012; Page et al. 2012; Delvecchio et al. 2014; Rodighiero et al. 2015, 2019; Fiore et al. 2017; Stanley et al. 2015, 2017; Massardi et al. 2018; Combes et al. 2019; D’Amato et al. 2020) before it attains a high enough mass and power to manifest as a bright AGN and eventually reduce\/quench star formation and partly evacuate gas and dust from the host (e.g., Granato et al. 2001, 2004; Lapi et al. 2011,2014, 2018). Another, albeit more indirect, indication of coevolution for the bulk of the BH and the host stellar mass comes from the similarity between the activity timescales of the central BH to the transition timescale of (green valley) galaxies from the blue cloud to the red sequence (see Wang et al. 2017; Lin et al. 2021, 2022; this is true apart from rejuvenations at late cosmic times; see Martin-Navarro et al. 2022).","Citation Text":["Kormendy & Ho 2013","Mullaney et al. 2012"],"Citation Start End":[[431,449],[1158,1178]]} {"Identifier":"2022ApJ...934...66SGranato_et_al._2001_Instance_1","Paragraph":"Accreting supermassive BHs can have a profound impact on the evolution of the host galaxies (see review by Alexander & Hickox 2012), as testified by the observed tight relationships between the relic BH masses and the physical properties of the hosts, most noticeably the stellar mass or velocity dispersion of the bulge component (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Gebhardt et al. 2000; Tremaine et al. 2002; Kormendy & Ho 2013; McConnell & Ma 2013; Reines & Volonteri 2015; Shankar et al. 2016, 2020a; Sahu et al. 2019; Zhu et al. 2021). These suggest that (apart from short-time stochastic fluctuations) the BH and the bulge stellar mass must have coevolved over comparable timescales, possibly determined by the energy feedback from the BH itself on the gas\/dust content of the host (see Tinsley 1980; Silk & Rees 1998; Fabian 1999; King 2005; Lapi et al. 2006, 2014, 2018; for a review, see King & Pounds 2015). In fact, targeted X-ray observations in the high-redshift star-forming progenitors of local massive galaxies have started to reveal the early growth of a dust-enshrouded (super)massive BH in their nuclear regions (e.g., Mullaney et al. 2012; Page et al. 2012; Delvecchio et al. 2014; Rodighiero et al. 2015, 2019; Fiore et al. 2017; Stanley et al. 2015, 2017; Massardi et al. 2018; Combes et al. 2019; D’Amato et al. 2020) before it attains a high enough mass and power to manifest as a bright AGN and eventually reduce\/quench star formation and partly evacuate gas and dust from the host (e.g., Granato et al. 2001, 2004; Lapi et al. 2011,2014, 2018). Another, albeit more indirect, indication of coevolution for the bulk of the BH and the host stellar mass comes from the similarity between the activity timescales of the central BH to the transition timescale of (green valley) galaxies from the blue cloud to the red sequence (see Wang et al. 2017; Lin et al. 2021, 2022; this is true apart from rejuvenations at late cosmic times; see Martin-Navarro et al. 2022).","Citation Text":["Granato et al. 2001"],"Citation Start End":[[1534,1553]]} {"Identifier":"2022ApJ...934...66SWang_et_al._2017_Instance_1","Paragraph":"Accreting supermassive BHs can have a profound impact on the evolution of the host galaxies (see review by Alexander & Hickox 2012), as testified by the observed tight relationships between the relic BH masses and the physical properties of the hosts, most noticeably the stellar mass or velocity dispersion of the bulge component (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Gebhardt et al. 2000; Tremaine et al. 2002; Kormendy & Ho 2013; McConnell & Ma 2013; Reines & Volonteri 2015; Shankar et al. 2016, 2020a; Sahu et al. 2019; Zhu et al. 2021). These suggest that (apart from short-time stochastic fluctuations) the BH and the bulge stellar mass must have coevolved over comparable timescales, possibly determined by the energy feedback from the BH itself on the gas\/dust content of the host (see Tinsley 1980; Silk & Rees 1998; Fabian 1999; King 2005; Lapi et al. 2006, 2014, 2018; for a review, see King & Pounds 2015). In fact, targeted X-ray observations in the high-redshift star-forming progenitors of local massive galaxies have started to reveal the early growth of a dust-enshrouded (super)massive BH in their nuclear regions (e.g., Mullaney et al. 2012; Page et al. 2012; Delvecchio et al. 2014; Rodighiero et al. 2015, 2019; Fiore et al. 2017; Stanley et al. 2015, 2017; Massardi et al. 2018; Combes et al. 2019; D’Amato et al. 2020) before it attains a high enough mass and power to manifest as a bright AGN and eventually reduce\/quench star formation and partly evacuate gas and dust from the host (e.g., Granato et al. 2001, 2004; Lapi et al. 2011,2014, 2018). Another, albeit more indirect, indication of coevolution for the bulk of the BH and the host stellar mass comes from the similarity between the activity timescales of the central BH to the transition timescale of (green valley) galaxies from the blue cloud to the red sequence (see Wang et al. 2017; Lin et al. 2021, 2022; this is true apart from rejuvenations at late cosmic times; see Martin-Navarro et al. 2022).","Citation Text":["Wang et al. 2017"],"Citation Start End":[[1873,1889]]} {"Identifier":"2015ApJ...811..132M__Martin_2005_Instance_1","Paragraph":"One of the important findings of the COS-Halos survey is that \n\n\n\n\n\n is omnipresent in the halos of SF galaxies which harbor a major reservoir of galactic metals (i.e., Tumlinson et al. 2011a). Outflows from the SF galaxies are thought to be the origin of highly ionized oxygen in the CGM. However, the outflows need not be active at the time of observations. Active outflows that are detected primarily via low-ions (e.g., \n\n\n\n\n\n, \n\n\n\n\n\n, \n\n\n\n\n\n) absorption in the spectra of host-galaxies (i.e., the “down-the-barrel” outflows) are also found to be ubiquitous at both high and low redshifts (Shapley et al. 2003; Martin 2005; Rupke et al. 2005; Veilleux et al. 2005; Rubin et al. 2010, 2014). Despite the ubiquity of winds, several basic questions that are key to quantifying galaxy feedback remain unanswered. How far do they propagate? What is the baryon mass that are processed through them? What is the mass-flow rate through winds? What are the mass loading factors and kinetic power of the winds? To what degree are metals processed through them? This is essentially because the location of the outflow with respect to host-galaxy is an unknown in “down-the-barrel” outflows. Galaxy outflow probed by a background QSO has the advantage of having the minimum distance between host-galaxy and outflowing material. For example, by analyzing a post-starburst outflow from a galaxy at \n\n\n\n\n\n detected in the spectra of QSO PG 1206+459 at an impact parameter of ∼68 kpc, Tripp et al. (2011) have shown that the entrained gas mass could be as large as ∼ few \n\n\n\n\n\n Numerous strong and large velocity spread (\n\n\n\n\n\n km s−1) metal absorption lines along with solar to super-solar metallicities in different absorption components suggest that the absorber is tracing an active outflow. Such wide velocity spread \n\n\n\n\n\n absorbers at low-z are also reported by Tumlinson et al. (2011b) and Muzahid (2014). In both these cases metallicity of the \n\n\n\n\n\n bearing gas is low (e.g., \n\n\n\n\n\n) which suggest that \n\n\n\n\n\n is probably tracing an “ancient outflow” (Ford et al. 2014) rather than an active wind. Interestingly, strong \n\n\n\n\n\n is detected in PG 1206+459 which is not present in the latter two systems. We note that the location of the absorbing gas with respect to the host-galaxy’s projected major and minor axes are not known for any of these strong \n\n\n\n\n\n absorbers.","Citation Text":["Martin 2005"],"Citation Start End":[[615,626]]} {"Identifier":"2020AandA...634A...1G__Barvainis_1987_Instance_1","Paragraph":"Theoretical and observational work argue for a strong correlation between the NIR size and the AGN luminosity (Suganuma et al. 2006; Kishimoto et al. 2011; Koshida et al. 2014; GRAVITY Collaboration 2019). In the standard picture, the NIR emission originates from the dust sublimation region, which is determined by the dust sublimation temperature Tsub. The temperature at which dust sublimates depends on the grain size and composition and ranges from Tsub ≈ 1500 K for silicate (Si) grains to Tsub ≈ 2000 K for graphite (C) grains (Baskin & Laor 2018). By assuming a grain size distribution typical for the interstellar medium (ISM), the mean sublimation distance can be calculated for graphite and silicate dust as \n\n\n\nR\n≈\n\na\nX\n\n×\n\nL\n\n46\n\n\n1\n\/\n2\n\n\n\n\n$ R\\approx a_{\\mathrm{X}}\\times L_{46}^{1\/2} $\n\n\n [pc] with aC = 0.5 and aSi = 1.3 (e.g. Barvainis 1987; Netzer 2015; for grain size dependence see Baskin & Laor 2018). However, there is evidence both from SED fitting (Mor & Netzer 2012) and from dust reverberation mapping (Kishimoto et al. 2007; Koshida et al. 2014) that, close to the AGN, one may find only larger graphite grains. Since, at the same distance from the AGN, large grains are cooler than small grains, one might naturally expect to find a distribution of large graphite grains at the smallest radii. In addition changes in the brightness of the AGN may lead to changes in the dust sublimation radius (Kishimoto et al. 2013) or instead, depending on the dust distribution, its temperature (Schnülle et al. 2015). As such, the sublimation radius is really rather a sublimation region according to grain size and species (e.g. Hönig & Kishimoto 2017; Baskin & Laor 2018). Empirical studies have found R2.2 μm ≈ 0.4 pc × (LAGN\/1046 erg s−1)1\/2 (assuming the V-band to Rsub relation from Koshida et al. 2014, and using the conversion LAGN ∼ 8L5500 Å from Netzer 2015), which corresponds to a good approximation to the sublimation radius of graphite. For NGC 1068 the observed relation from Koshida et al. (2014) predicts a dust sublimation radius in the range R2.2 μm ≈ 0.08–0.27 pc, for the luminosity range quoted in Table 1.","Citation Text":["Barvainis 1987"],"Citation Start End":[[843,857]]} {"Identifier":"2018ApJ...860..153M__Petroff_et_al._2015_Instance_1","Paragraph":"It is expected that the polarization properties produced by the thermal–nonthermal electrons have wide applications to many kinds of synchrotron sources. Here, we propose some examples. Covino et al. (2017) detected the low-level linear polarization of AT 2017gfo\/GW170817 during the kilonova phase. Although the measured polarization seems to be due to the Galactic dust along the line of sight, we think that future synchrotron polarization detections for electromagnetic counterparts of gravitational wave events can be applied to further investigate compact object merger systems and constrain detailed physics of gravitational wave events. Fast radio burst (FRB) 140514 has the linear polarization limit of \n\n\n\n\n\n and the circular polarization degree of 21 ± 7% (Petroff et al. 2015). The development of the radio polarization measurements on FRBs are carried out to reveal the FRB origin. Covino & Götz (2016) summarized the polarization observation of GRB prompt and afterglow emissions, and the GRB jet geometry related to the polarization was also mentioned. Steele et al. (2017) presented the optical polarization results of some GRBs, and the linear polarization degrees are relatively low (see also the recent report of Wiersema & Covino 2018 on GRB 180205A). Moreover, the circular polarization was detected in GRB 121024A (Wiersema et al. 2014). Spectropolarimetric detection of either supernova Ia (SN Ia) or core-collapse supernova was performed (Tanaka et al. 2012; Porter et al. 2016). The polarization properties can be helpful to further explore SN explosion mechanisms. Thermal electrons cannot be ignored in the celestial objects mentioned above, and we should consider the thermal electron contribution to the synchrotron polarization. Moreover, some objects, such as kilonova, GRB, and SN as mentioned above, have dense environments (D’Elia et al. 2007; Kasen et al. 2013; Tanaka & Hotokezaka 2013; Buckey et al. 2018; Yang et al. 2018). Polarization radiative transfer should be taken into account when we consider the polarization measurements in the optical and radio bands. In this paper, we do not attempt to reproduce these different polarization properties with exact modeling parameters. However, these polarization detections of the different populations encourage us to further explore the possibility of applying our scenario, when we assume that all of these kinds of sources are dominated by the synchrotron radiation.","Citation Text":["Petroff et al. 2015"],"Citation Start End":[[768,787]]} {"Identifier":"2016MNRAS.460.1625P__Fialkov_et_al._2012_Instance_1","Paragraph":"Recent work by Tseliakhovich & Hirata (2010) showed that, at the time of recombination, baryons were moving in a coherent manner (on scales of ≲3 Mpc comoving) with respect to the dark matter and had an rms velocity of ∼30 km s−1. Since, on small scales, the baryons effectively displayed a streaming motion with respect to the dark matter component, their relative velocity is usually referred to as a ‘stream velocity’ in the literature, and we adopt this convention throughout this work. Tseliakhovich & Hirata (2010) also argued that, since shortly after recombination the temperature of the baryons (and hence the sound speed) drops precipitously, the streaming motion of the baryons becomes supersonic and it can potentially have a dramatic impact on structure formation. Subsequent studies, both theoretical and numerical, showed that the large stream velocity of baryons has profound implications on the total number density of haloes (Tseliakhovich & Hirata 2010; Maio, Koopman & Ciardi 2011; Stacy, Bromm & Loeb 2011; Tseliakhovich, Barkana & Hirata 2011; Fialkov et al. 2012; Naoz, Yoshida & Gnedin 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013; Tanaka, Li & Haiman 2013; Tanaka & Li 2014; Asaba, Ichiki & Tashiro 2016), the size of the haloes that are able to retain gas at a given redshift (Naoz, Yoshida & Gnedin 2013), the overall gas fraction in haloes (Dalal, Pen & Seljak 2010; Greif et al. 2011; Maio et al. 2011; Tseliakhovich et al. 2011; Fialkov et al. 2012; Naoz et al. 2012, 2013; O'Leary & McQuinn 2012; Richardson, Scannapieco & Thacker 2013; Asaba et al. 2016), the gas density and temperature profiles (Greif et al. 2011; Liu & Wang 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Richardson et al. 2013), the halo mass threshold in which star formation occurs (Liu & Wang 2011; Maio et al. 2011; Greif et al. 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013), as well as black hole evolution (Tanaka et al. 2013; Tanaka & Li 2014; Latif, Niemeyer & Schleicher 2014) and magnetic fields (Naoz & Narayan 2013). A thorough review of the implications of the stream velocity on structure formation is presented in Fialkov (2014).","Citation Text":["Fialkov et al. 2012"],"Citation Start End":[[1066,1085]]} {"Identifier":"2016MNRAS.460.1625P__Fialkov_et_al._2012_Instance_2","Paragraph":"Recent work by Tseliakhovich & Hirata (2010) showed that, at the time of recombination, baryons were moving in a coherent manner (on scales of ≲3 Mpc comoving) with respect to the dark matter and had an rms velocity of ∼30 km s−1. Since, on small scales, the baryons effectively displayed a streaming motion with respect to the dark matter component, their relative velocity is usually referred to as a ‘stream velocity’ in the literature, and we adopt this convention throughout this work. Tseliakhovich & Hirata (2010) also argued that, since shortly after recombination the temperature of the baryons (and hence the sound speed) drops precipitously, the streaming motion of the baryons becomes supersonic and it can potentially have a dramatic impact on structure formation. Subsequent studies, both theoretical and numerical, showed that the large stream velocity of baryons has profound implications on the total number density of haloes (Tseliakhovich & Hirata 2010; Maio, Koopman & Ciardi 2011; Stacy, Bromm & Loeb 2011; Tseliakhovich, Barkana & Hirata 2011; Fialkov et al. 2012; Naoz, Yoshida & Gnedin 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013; Tanaka, Li & Haiman 2013; Tanaka & Li 2014; Asaba, Ichiki & Tashiro 2016), the size of the haloes that are able to retain gas at a given redshift (Naoz, Yoshida & Gnedin 2013), the overall gas fraction in haloes (Dalal, Pen & Seljak 2010; Greif et al. 2011; Maio et al. 2011; Tseliakhovich et al. 2011; Fialkov et al. 2012; Naoz et al. 2012, 2013; O'Leary & McQuinn 2012; Richardson, Scannapieco & Thacker 2013; Asaba et al. 2016), the gas density and temperature profiles (Greif et al. 2011; Liu & Wang 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Richardson et al. 2013), the halo mass threshold in which star formation occurs (Liu & Wang 2011; Maio et al. 2011; Greif et al. 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013), as well as black hole evolution (Tanaka et al. 2013; Tanaka & Li 2014; Latif, Niemeyer & Schleicher 2014) and magnetic fields (Naoz & Narayan 2013). A thorough review of the implications of the stream velocity on structure formation is presented in Fialkov (2014).","Citation Text":["Fialkov et al. 2012"],"Citation Start End":[[1464,1483]]} {"Identifier":"2016MNRAS.460.1625P__Fialkov_et_al._2012_Instance_3","Paragraph":"Recent work by Tseliakhovich & Hirata (2010) showed that, at the time of recombination, baryons were moving in a coherent manner (on scales of ≲3 Mpc comoving) with respect to the dark matter and had an rms velocity of ∼30 km s−1. Since, on small scales, the baryons effectively displayed a streaming motion with respect to the dark matter component, their relative velocity is usually referred to as a ‘stream velocity’ in the literature, and we adopt this convention throughout this work. Tseliakhovich & Hirata (2010) also argued that, since shortly after recombination the temperature of the baryons (and hence the sound speed) drops precipitously, the streaming motion of the baryons becomes supersonic and it can potentially have a dramatic impact on structure formation. Subsequent studies, both theoretical and numerical, showed that the large stream velocity of baryons has profound implications on the total number density of haloes (Tseliakhovich & Hirata 2010; Maio, Koopman & Ciardi 2011; Stacy, Bromm & Loeb 2011; Tseliakhovich, Barkana & Hirata 2011; Fialkov et al. 2012; Naoz, Yoshida & Gnedin 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013; Tanaka, Li & Haiman 2013; Tanaka & Li 2014; Asaba, Ichiki & Tashiro 2016), the size of the haloes that are able to retain gas at a given redshift (Naoz, Yoshida & Gnedin 2013), the overall gas fraction in haloes (Dalal, Pen & Seljak 2010; Greif et al. 2011; Maio et al. 2011; Tseliakhovich et al. 2011; Fialkov et al. 2012; Naoz et al. 2012, 2013; O'Leary & McQuinn 2012; Richardson, Scannapieco & Thacker 2013; Asaba et al. 2016), the gas density and temperature profiles (Greif et al. 2011; Liu & Wang 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Richardson et al. 2013), the halo mass threshold in which star formation occurs (Liu & Wang 2011; Maio et al. 2011; Greif et al. 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013), as well as black hole evolution (Tanaka et al. 2013; Tanaka & Li 2014; Latif, Niemeyer & Schleicher 2014) and magnetic fields (Naoz & Narayan 2013). A thorough review of the implications of the stream velocity on structure formation is presented in Fialkov (2014).","Citation Text":["Fialkov et al. 2012"],"Citation Start End":[[1851,1870]]} {"Identifier":"2016MNRAS.460.1625P__Fialkov_et_al._2012_Instance_4","Paragraph":"Recent work by Tseliakhovich & Hirata (2010) showed that, at the time of recombination, baryons were moving in a coherent manner (on scales of ≲3 Mpc comoving) with respect to the dark matter and had an rms velocity of ∼30 km s−1. Since, on small scales, the baryons effectively displayed a streaming motion with respect to the dark matter component, their relative velocity is usually referred to as a ‘stream velocity’ in the literature, and we adopt this convention throughout this work. Tseliakhovich & Hirata (2010) also argued that, since shortly after recombination the temperature of the baryons (and hence the sound speed) drops precipitously, the streaming motion of the baryons becomes supersonic and it can potentially have a dramatic impact on structure formation. Subsequent studies, both theoretical and numerical, showed that the large stream velocity of baryons has profound implications on the total number density of haloes (Tseliakhovich & Hirata 2010; Maio, Koopman & Ciardi 2011; Stacy, Bromm & Loeb 2011; Tseliakhovich, Barkana & Hirata 2011; Fialkov et al. 2012; Naoz, Yoshida & Gnedin 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013; Tanaka, Li & Haiman 2013; Tanaka & Li 2014; Asaba, Ichiki & Tashiro 2016), the size of the haloes that are able to retain gas at a given redshift (Naoz, Yoshida & Gnedin 2013), the overall gas fraction in haloes (Dalal, Pen & Seljak 2010; Greif et al. 2011; Maio et al. 2011; Tseliakhovich et al. 2011; Fialkov et al. 2012; Naoz et al. 2012, 2013; O'Leary & McQuinn 2012; Richardson, Scannapieco & Thacker 2013; Asaba et al. 2016), the gas density and temperature profiles (Greif et al. 2011; Liu & Wang 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Richardson et al. 2013), the halo mass threshold in which star formation occurs (Liu & Wang 2011; Maio et al. 2011; Greif et al. 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013), as well as black hole evolution (Tanaka et al. 2013; Tanaka & Li 2014; Latif, Niemeyer & Schleicher 2014) and magnetic fields (Naoz & Narayan 2013). A thorough review of the implications of the stream velocity on structure formation is presented in Fialkov (2014).","Citation Text":["Fialkov (2014)"],"Citation Start End":[[2167,2181]]} {"Identifier":"2016MNRAS.460.1625PTseliakhovich_&_Hirata_(2010)_Instance_1","Paragraph":"Recent work by Tseliakhovich & Hirata (2010) showed that, at the time of recombination, baryons were moving in a coherent manner (on scales of ≲3 Mpc comoving) with respect to the dark matter and had an rms velocity of ∼30 km s−1. Since, on small scales, the baryons effectively displayed a streaming motion with respect to the dark matter component, their relative velocity is usually referred to as a ‘stream velocity’ in the literature, and we adopt this convention throughout this work. Tseliakhovich & Hirata (2010) also argued that, since shortly after recombination the temperature of the baryons (and hence the sound speed) drops precipitously, the streaming motion of the baryons becomes supersonic and it can potentially have a dramatic impact on structure formation. Subsequent studies, both theoretical and numerical, showed that the large stream velocity of baryons has profound implications on the total number density of haloes (Tseliakhovich & Hirata 2010; Maio, Koopman & Ciardi 2011; Stacy, Bromm & Loeb 2011; Tseliakhovich, Barkana & Hirata 2011; Fialkov et al. 2012; Naoz, Yoshida & Gnedin 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013; Tanaka, Li & Haiman 2013; Tanaka & Li 2014; Asaba, Ichiki & Tashiro 2016), the size of the haloes that are able to retain gas at a given redshift (Naoz, Yoshida & Gnedin 2013), the overall gas fraction in haloes (Dalal, Pen & Seljak 2010; Greif et al. 2011; Maio et al. 2011; Tseliakhovich et al. 2011; Fialkov et al. 2012; Naoz et al. 2012, 2013; O'Leary & McQuinn 2012; Richardson, Scannapieco & Thacker 2013; Asaba et al. 2016), the gas density and temperature profiles (Greif et al. 2011; Liu & Wang 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Richardson et al. 2013), the halo mass threshold in which star formation occurs (Liu & Wang 2011; Maio et al. 2011; Greif et al. 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013), as well as black hole evolution (Tanaka et al. 2013; Tanaka & Li 2014; Latif, Niemeyer & Schleicher 2014) and magnetic fields (Naoz & Narayan 2013). A thorough review of the implications of the stream velocity on structure formation is presented in Fialkov (2014).","Citation Text":["Tseliakhovich & Hirata (2010)"],"Citation Start End":[[15,44]]} {"Identifier":"2016MNRAS.460.1625PTseliakhovich_&_Hirata_(2010)_Instance_2","Paragraph":"Recent work by Tseliakhovich & Hirata (2010) showed that, at the time of recombination, baryons were moving in a coherent manner (on scales of ≲3 Mpc comoving) with respect to the dark matter and had an rms velocity of ∼30 km s−1. Since, on small scales, the baryons effectively displayed a streaming motion with respect to the dark matter component, their relative velocity is usually referred to as a ‘stream velocity’ in the literature, and we adopt this convention throughout this work. Tseliakhovich & Hirata (2010) also argued that, since shortly after recombination the temperature of the baryons (and hence the sound speed) drops precipitously, the streaming motion of the baryons becomes supersonic and it can potentially have a dramatic impact on structure formation. Subsequent studies, both theoretical and numerical, showed that the large stream velocity of baryons has profound implications on the total number density of haloes (Tseliakhovich & Hirata 2010; Maio, Koopman & Ciardi 2011; Stacy, Bromm & Loeb 2011; Tseliakhovich, Barkana & Hirata 2011; Fialkov et al. 2012; Naoz, Yoshida & Gnedin 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013; Tanaka, Li & Haiman 2013; Tanaka & Li 2014; Asaba, Ichiki & Tashiro 2016), the size of the haloes that are able to retain gas at a given redshift (Naoz, Yoshida & Gnedin 2013), the overall gas fraction in haloes (Dalal, Pen & Seljak 2010; Greif et al. 2011; Maio et al. 2011; Tseliakhovich et al. 2011; Fialkov et al. 2012; Naoz et al. 2012, 2013; O'Leary & McQuinn 2012; Richardson, Scannapieco & Thacker 2013; Asaba et al. 2016), the gas density and temperature profiles (Greif et al. 2011; Liu & Wang 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Richardson et al. 2013), the halo mass threshold in which star formation occurs (Liu & Wang 2011; Maio et al. 2011; Greif et al. 2011; Fialkov et al. 2012; O'Leary & McQuinn 2012; Bovy & Dvorkin 2013), as well as black hole evolution (Tanaka et al. 2013; Tanaka & Li 2014; Latif, Niemeyer & Schleicher 2014) and magnetic fields (Naoz & Narayan 2013). A thorough review of the implications of the stream velocity on structure formation is presented in Fialkov (2014).","Citation Text":["Tseliakhovich & Hirata (2010)"],"Citation Start End":[[491,520]]} {"Identifier":"2018MNRAS.475.3543G__Elbaz_et_al._2007_Instance_1","Paragraph":"Gohil & Ballantyne (2017) showed that the AGN obscuration phenomenon depends on the gas fraction in NSDs. With a higher gas fraction, a greater amount of gas is available to accrete, which increases a column of gas in annulus Σmp and, in turn, controls expansion of the atmosphere. The overall gas fraction (f0) in galaxies is observed to be increasing with redshift. f0 is related to the depletion time and the specific star-formation rate (sSFR) through\n(16)\r\n\\begin{eqnarray}\r\nf_0(z)=\\frac{1}{1+[t_{\\rm dep}(z){\\rm sSFR}(z)]^{-1}}.\r\n\\end{eqnarray}\r\nThe depletion time is estimated to be (Saintonge et al. 2013)\n(17)\r\n\\begin{eqnarray}\r\nt_{\\rm dep}=1.5(1+z)^{\\alpha } [{\\rm Gyr}],\r\n\\end{eqnarray}\r\nwith α = −1.0 (Tacconi et al. 2013). Lilly et al. (2013) provide an analytical expression for the evolution of sSFR, given by\n(18)\r\n\\begin{eqnarray}\r\n{\\rm sSFR}(M_*,z)= \\left\\lbrace \\begin{array}{@{}l@{\\quad }l@{}}0.07\\Big (\\frac{M_*}{10^{10.5} \\, \\mathrm{M}_{\\odot }}\\Big )^{-0.1} (1+z)^3\\ \\ & z<2,\\\\\r\n 0.30\\Big (\\frac{M_*}{10^{10.5} \\, \\mathrm{M}_{\\odot }}\\Big )^{-0.1} (1+z)^{5\/3}\\ \\ & z\\ge 2, \\end{array}\\right.\r\n\\end{eqnarray}\r\nwhich was motivated by observational data (e.g. Daddi et al. 2007; Elbaz et al. 2007; Noeske et al. 2007; Pannella et al. 2009; Stark et al. 2013). Since there is a weak dependence on the galaxy mass M*, we choose M* = 1010.5 M⊙. Then the distribution of the gas fraction (Φf) is assumed to be Gaussian around f0 and is given by\n(19)\r\n\\begin{eqnarray}\r\n\\Phi _{\\rm f}(z,f)=\\frac{1}{\\sqrt{2 {\\pi} }\\sigma _{\\rm f}}\\exp \\Big [-\\frac{(f-f_0)^2}{2\\sigma _{\\rm f}^2}\\Big ].\r\n\\end{eqnarray}\r\nThe dispersion σf is estimated to be 0.2 by roughly fitting a Gaussian to the results of Tacconi et al. (2013). Finally, we can compute the weights Wf of input parameter f ≡ fg, out from\n(20)\r\n\\begin{eqnarray}\r\nW_{\\rm f}(z,f)=\\frac{\\Phi _{\\rm f}(z,f)}{\\sum \\limits _{k}\\Phi _{\\rm f}(z,f_k)},\r\n\\end{eqnarray}\r\nwhere\n(21)\r\n\\begin{eqnarray}\r\nf_k\\in [0.2,0.4,0.6,0.8].\r\n\\end{eqnarray}\r\nThe right panel of Fig. 1 shows the evolution of 20, 40, 60 and 80 per cent gas fraction with redshift, represented by black, red, blue and green curves, respectively. At low redshift, NSDs with low gas fraction dominate the sample, while NSDs with a 40 per cent gas fraction dominate at 1 z 2. Beyond z = 2, NSDs with a 60 per cent gas fraction dominate. Wf of NSDs with low gas fraction decrease overall with redshift and the reverse is true for NSDs with high gas fraction (60 and 80 per cent). Similarly to the observational evidence, the figure illustrates that the dominant gas fraction increases with z and its evolution flattens out at higher redshift.","Citation Text":["Elbaz et al. 2007"],"Citation Start End":[[1207,1224]]} {"Identifier":"2015ApJ...805..122L__Richards_et_al._2011_Instance_1","Paragraph":"PHL 1811 itself has an estimated Eddington ratio of \n\n\n\n\n\n (Leighly et al. 2007b). PHL 1811, along with several PHL 1811 analogs and WLQs with rest-frame optical spectra (J1521+5202, 2QZ J2154–3056, and the two high-redshift WLQs in Shemmer et al. 2010), have weak or undetected [O iii] \n\n\n\n\n\n narrow emission lines, suggestive of high Eddington ratios (e.g., Boroson & Green 1992; Shen & Ho 2014). Moreover, several studies have found that as \n\n\n\n\n\n increases, the C iv REW generally decreases and the C iv blueshift also increases (e.g., Bachev et al. 2004; Baskin & Laor 2004; Richards et al. 2011; Shen & Ho 2014; Sulentic et al. 2014; Shemmer & Lieber 2015). In these correlations, there is only limited sampling in the super-Eddington or low (\n\n\n\n\n\n Å) C iv REW regime, but the overall trends suggest that the Eddington ratio grows as one moves from typical quasars toward WLQs in the C iv REW versus blueshift space (Figure 3(a)). By the nature of our selection of the PHL 1811 analogs and WLQs, demanding that the BELR does not produce normal emission lines, we may have recovered effectively a population of quasars with (extremely) high Eddington ratios. It is difficult to measure \n\n\n\n\n\n directly for our exceptional objects, as the SMBH masses estimated from the line-based virial method are likely highly uncertain and perhaps systematically in error (Section 5.3). However, based on the empirical Γ\n\n\n\n\n\n relations, our joint spectral analysis of the X-ray normal subsample in Sections 5.2 and 5.3 does indicate a high Eddington ratio (\n\n\n\n\n\n) in general for our quasars.33\n\n33\nNarrow-line Seyfert 1 galaxies (NLS1s) also generally have steep X-ray spectra and high Eddington ratios. PHL 1811 itself is considered a NLS1 (Leighly et al. 2001), and NIR spectroscopy of a limited sample of WLQs shows that they have in general narrow Hβ and strong optical Fe ii emission (see Section 5.1 of Plotkin et al. 2015), similar to NLS1s. However, as the line widths and REWs have likely dependences on luminosity, our PHL 1811 analogs and WLQs are not directly comparable to local, less-luminous NLS1s.\n\n","Citation Text":["Richards et al. 2011"],"Citation Start End":[[580,600]]} {"Identifier":"2020ApJ...904...98R__Guillochon_&_Ramirez-Ruiz_2013_Instance_1","Paragraph":"Phinney (1989) was the first to recognize that \n\n\n\n\n\n is not exactly the maximum orbital pericenter for a complete tidal disruption, a distance we would like to name the “physical tidal radius” (we assign it the symbol \n\n\n\n\n\n). To remedy the neglect of internal stellar structure, he suggested that \n\n\n\n\n\n could be estimated by applying to \n\n\n\n\n\n a correction factor based on the star’s apsidal motion constant and its dimensionless binding energy. For this reason, \n\n\n\n\n\n is sometimes reinterpreted to be \n\n\n\n\n\n, but without evaluating how it might differ from \n\n\n\n\n\n (Stone et al. 2013). Several groups have tried to include stellar structure in the calculation of \n\n\n\n\n\n, but employing purely Newtonian dynamics on polytropic stars (e.g., Luminet & Carter 1986; Khokhlov et al. 1993; Guillochon & Ramirez-Ruiz 2013; Mainetti et al. 2017). Recently, there have been efforts beginning from genuine main-sequence stellar structures, but still restricted to Newtonian dynamics, and examining a limited range of stellar masses (only 1 \n\n\n\n\n\n in Goicovic et al. 2019, \n\n\n\n\n\n and \n\n\n\n\n\n at several ages in Law-Smith et al. 2019, \n\n\n\n\n\n, \n\n\n\n\n\n, and \n\n\n\n\n\n at three different ages in Golightly et al. 2019). Others have explored the dependence on black hole mass induced by relativistic effects, but without any reference to internal stellar structure or the hydrodynamics of disruption (e.g., Ivanov & Chernyakova 2006; Kesden 2012; Servin & Kesden 2017). Earlier works employed a post-Newtonain approximation (e.g., Ayal et al. 2000) or explored the use of relativistic hydrodynamics simulations for strong encounters of polytropic stars, but without stellar self-gravity (e.g., Laguna et al. 1993). In some cases, relativistic effects were approximated by a “generalized Newtonian potential” (e.g., Gafton et al. 2015; Gafton & Rosswog 2019) or in terms of genuine relativistic dynamics (e.g., Frolov et al. 1994), but assuming a polytropic structure for the star and computing stellar self-gravity in an entirely Newtonian fashion (in the last case, fixing it to its initial stellar surface value). Many of these explorations of \n\n\n\n\n\n also computed the energy distribution dM\/dE and explored the relation between the remnant mass and orbital pericenter in partial disruptions; in one case (Manukian et al. 2013), they also examined the remnants’ orbital properties. However, all this work was subject to the limitations already enumerated.","Citation Text":["Guillochon & Ramirez-Ruiz 2013"],"Citation Start End":[[787,817]]} {"Identifier":"2016ApJ...825L..15C__Ossenkopf_&_Henning_1994_Instance_1","Paragraph":"Figure 1 presents the Stokes I image from W43-MM1. The continuum emission shows a fragmented filament extending from the north to the south–west. Two bright sources at the center, A and B1, completely dominate the energy budget in W43-MM1 (with integrated fluxes of ∼2.0 and 0.5 Jy, which correspond to \n\n\n\n\n\n of the total flux recovered), over a number of additional fragments extending to the south–west. Also, additional sources to the east and west have been detected. Comparing with the SMA results from Sridharan et al. (2014) and the PdBI 1 mm results from Louvet et al. (2014), the ALMA observations reproduce quite well the overall morphology of W43-MM1, but with better resolution. The noise in the ALMA map is \n\n\n\n\n\n with a peak of 503 mJy \n\n\n\n\n\n obtained from Gaussian fitting. We used the getsources algorithm (Men'shchikov et al. 2012) to successfully extract 14 sources from our ALMA data (see Table 1 and Figure 1). The extraction was later compared to other methods such as clumpfind (Williams et al. 1994), FellWalker, and Reinhold (Berry et al. 2007) obtaining a good agreement with the selection produced by getsources. We used the source positions and sizes derived using getsources as initial guess for a Gaussian 2D fitting (using CASA imfit algorithm) in order to derive accurate fluxes from the extracted sources.14\n\n14\nWe found that getsources tends to underestimate the recovered fluxes from our data.\n Also, we kept the same source nomenclature used by Sridharan et al. (2014), but adding numbers where higher multiplicity was discovered with respect to the SMA map. Using the standard procedure to calculate masses from dust emission (Hildebrand 1983), we computed masses for all 15 sources in our catalog assuming a dust opacity of \n\n\n\n\n\n cm2 g−1 (Ossenkopf & Henning 1994), a gas to dust ratio of 1:100, and a dust temperature of \n\n\n\n\n\n K (Bally et al. 2010), with the exception of the hot core, source A, where we used a range between \n\n\n\n\n\n K. Although the SMA detected CH3CN emission toward B1 and C, it was unresolved and not sufficient to derived temperatures; hence, we used \n\n\n\n\n\n K for these sources. Herpin et al. (2012) modeled an spectral energy distribution and derived a temperature profile for source A using all the publicly available data on W43-MM1 to date. Their model suggests a temperature of ∼150 K at 2500 au distance (05 radial; \n\n\n\n\n\n size) and ∼70 K at about 8000 au distance (07 radial; 14 size), which are the length scales sampled by ALMA. However, if larger spatial scales than our source size are considered, the temperature might be lower and on the order of 30 K (as suggested by Bally et al. 2010). These scales (\n\n\n\n\n\n) are consistent with Herschel primary beam at 160 μm and, of course, larger than our deconvolved source sizes and synthesized beam. Therefore, and using this temperature range, our derived mass for source A is between 312 and 146 M\n\n\n\n\n\n(with the exception of the 30 K temperature derived mass of 728 M\n\n\n\n\n\n). These estimates put source A below other massive clumps such as the SDC335-MM1 mass estimate of 545 M\n\n\n\n\n\n(Peretto et al. 2013) and G31.41+0.31 with a mass estimate of 577 M\n\n\n\n\n\n (Girart et al. 2009).15\n\n15\nNote that in this massive core a magnetic field strength of 10 mG was derived using n(H2) = \n\n\n\n\n\n cm−3.\n However, these mass estimates were derived from observations sampling larger length scales than our ALMA W43 observations. The deconvolved size of SDC335-MM1 is about 0.054, which is two times the size of source A or four times the area. A simple estimate assuming an \n\n\n\n\n\n density profile, will give about 272 M\n\n\n\n\n\n per source A size for SDC335-MM1 and about 205 M\n\n\n\n\n\n per source A size for G31.41+0.31.","Citation Text":["Ossenkopf & Henning 1994"],"Citation Start End":[[1778,1802]]} {"Identifier":"2018MNRAS.481.1631B__Bowler_et_al._2012_Instance_1","Paragraph":"The ALMA data were obtained in Cycle 3 through proposal 2015.1.00540.S (PI: R. A. A. Bowler). We observed the six brightest LBGs at 6.5 $z$ 7.5 presented in Bowler et al. (2012, 2014). The galaxies are all within the COSMOS field (Scoville et al. 2007a),1 and were initially selected in the near-IR YJHKs data based on the UltraVISTA2 survey data release 2 (McCracken et al. 2012). The coordinates of the six galaxies, which defined each ALMA pointing, and their photometric redshifts are shown in Table 1. The galaxies were selected via SED fitting and are secure $z$ > 6.5 objects as demonstrated by the sharp spectral break observed in the photometric data at ${\\simeq } 1\\, {\\mu} {\\rm m}$ (Fig. A1). The strength of the break ($z - Y \\gt 2\\, {\\rm mag}$) observed in the sample cannot be reproduced by the common low-redshift or brown-dwarf contaminants (e.g. Ouchi et al. 2010; Bouwens et al. 2011; Bowler et al. 2012). Each target was observed for 10 min in Band 6 (centred at $233\\, {\\rm GHz}$ or $1.29\\, {\\rm mm}$; corresponding to ∼170 ${\\mu}$m in the rest frame). The integration time was chosen to provide limits on the ratio of FIR to UV luminosity sufficient to distinguish between the previous results at $z$ > 5 from Watson et al. (2015) and Capak et al. (2015). The data were taken in a compact configuration C36-2, with a maximum baseline of 330 m, on 2016 January 25. In order to maximize continuum sensitivity, the correlator was set up in time division mode with 2 GHz bandwidth across each of four spectral windows (centred at 224, 226, 240, 242 GHz) in two polarizations. The data were reduced with the ALMA pipeline of casa version 4.5.1. Calibration was performed by ALMA personnel using J1058+0133, J0948+0022, and Ganymede for bandpass, phase, and flux calibration, respectively. We then processed the data through the imaging pipeline, collapsing the full 8 GHz bandwidth and both polarizations into a single-continuum image of each field, initially using natural weighting of baselines to obtain the optimal root-mean-square (rms) sensitivity for point sources. Imaging was achieved using the tclean task, and the data were cleaned by defining a mask for any source in the field with a peak signal-to-noise ratio (SNR) > 3 that also corresponds to a Hubble Space Telescope(HST)-detected galaxy (whether the target or serendipitous), with a clean threshold of 60 ${\\mu}$Jy (≃ 2 × rms). The natural weighted images have a beam size of 1.1 × 1.4 arcsec full width at half-maximum (FWHM) and reach an average rms sensitivity of $27\\, {\\mu} {\\rm Jy}\\,{\\rm beam}^{-1}$, with small deviations of $2 \\, {\\mu} {\\rm Jy}\\,{\\rm beam}^{-1}$ between the different pointings. To increase the sensitivity to extended flux, we also tried imaging the targets with a 1 arcsec taper, which results in a beam size of 1.4 × 1.7 arcsec and rms sensitivity of $31\\, {\\mu} {\\rm Jy}\\,{\\rm beam}^{-1}$. As the natural weighted images have a smaller beam and better rms sensitivity, we chose to present this weighting throughout the paper, however comment on the tapered results where relevant. We measured fluxes using two complementary methods. First, fluxes were measured from the peak flux within an aperture of radius 1 arcsec from the HST\/WFC3 centroid. The peak flux assumes that the source is unresolved in the ALMA data. For the stacks and the detected individual source, we also measured the total flux using a Gaussian fit. In the case of a non-detection at the 3σ level for the individual LBGs, we conservatively provide 2σ upper limits calculated as $f_{\\rm peak} + 2\\, \\times \\, {\\rm rms}$.","Citation Text":["Bowler et al. (2012"],"Citation Start End":[[159,178]]} {"Identifier":"2018MNRAS.481.1631B__Bowler_et_al._2012_Instance_2","Paragraph":"The ALMA data were obtained in Cycle 3 through proposal 2015.1.00540.S (PI: R. A. A. Bowler). We observed the six brightest LBGs at 6.5 $z$ 7.5 presented in Bowler et al. (2012, 2014). The galaxies are all within the COSMOS field (Scoville et al. 2007a),1 and were initially selected in the near-IR YJHKs data based on the UltraVISTA2 survey data release 2 (McCracken et al. 2012). The coordinates of the six galaxies, which defined each ALMA pointing, and their photometric redshifts are shown in Table 1. The galaxies were selected via SED fitting and are secure $z$ > 6.5 objects as demonstrated by the sharp spectral break observed in the photometric data at ${\\simeq } 1\\, {\\mu} {\\rm m}$ (Fig. A1). The strength of the break ($z - Y \\gt 2\\, {\\rm mag}$) observed in the sample cannot be reproduced by the common low-redshift or brown-dwarf contaminants (e.g. Ouchi et al. 2010; Bouwens et al. 2011; Bowler et al. 2012). Each target was observed for 10 min in Band 6 (centred at $233\\, {\\rm GHz}$ or $1.29\\, {\\rm mm}$; corresponding to ∼170 ${\\mu}$m in the rest frame). The integration time was chosen to provide limits on the ratio of FIR to UV luminosity sufficient to distinguish between the previous results at $z$ > 5 from Watson et al. (2015) and Capak et al. (2015). The data were taken in a compact configuration C36-2, with a maximum baseline of 330 m, on 2016 January 25. In order to maximize continuum sensitivity, the correlator was set up in time division mode with 2 GHz bandwidth across each of four spectral windows (centred at 224, 226, 240, 242 GHz) in two polarizations. The data were reduced with the ALMA pipeline of casa version 4.5.1. Calibration was performed by ALMA personnel using J1058+0133, J0948+0022, and Ganymede for bandpass, phase, and flux calibration, respectively. We then processed the data through the imaging pipeline, collapsing the full 8 GHz bandwidth and both polarizations into a single-continuum image of each field, initially using natural weighting of baselines to obtain the optimal root-mean-square (rms) sensitivity for point sources. Imaging was achieved using the tclean task, and the data were cleaned by defining a mask for any source in the field with a peak signal-to-noise ratio (SNR) > 3 that also corresponds to a Hubble Space Telescope(HST)-detected galaxy (whether the target or serendipitous), with a clean threshold of 60 ${\\mu}$Jy (≃ 2 × rms). The natural weighted images have a beam size of 1.1 × 1.4 arcsec full width at half-maximum (FWHM) and reach an average rms sensitivity of $27\\, {\\mu} {\\rm Jy}\\,{\\rm beam}^{-1}$, with small deviations of $2 \\, {\\mu} {\\rm Jy}\\,{\\rm beam}^{-1}$ between the different pointings. To increase the sensitivity to extended flux, we also tried imaging the targets with a 1 arcsec taper, which results in a beam size of 1.4 × 1.7 arcsec and rms sensitivity of $31\\, {\\mu} {\\rm Jy}\\,{\\rm beam}^{-1}$. As the natural weighted images have a smaller beam and better rms sensitivity, we chose to present this weighting throughout the paper, however comment on the tapered results where relevant. We measured fluxes using two complementary methods. First, fluxes were measured from the peak flux within an aperture of radius 1 arcsec from the HST\/WFC3 centroid. The peak flux assumes that the source is unresolved in the ALMA data. For the stacks and the detected individual source, we also measured the total flux using a Gaussian fit. In the case of a non-detection at the 3σ level for the individual LBGs, we conservatively provide 2σ upper limits calculated as $f_{\\rm peak} + 2\\, \\times \\, {\\rm rms}$.","Citation Text":["Bowler et al. 2012"],"Citation Start End":[[905,923]]} {"Identifier":"2019MNRAS.482.3249Z__Damour_&_Esposito-Farèse_1992b_Instance_1","Paragraph":"A non-vanishing α1 adds to the polarization of the orbit in the same way as a non-vanishing α3, and analogous to equation (13) one finds for the change of the orbital eccentricity vector \n(17)\r\n\\begin{eqnarray*}\r\n\\dot{\\boldsymbol {e}} = \\dot{\\boldsymbol {e}}_{\\hat{\\alpha }_1} + \\dot{\\boldsymbol {e}}_{\\hat{\\alpha }_3} + \\dot{\\omega }_{\\rm PN}\\, \\hat{\\boldsymbol {k}} \\times {\\boldsymbol {e}} \\, , \r\n\\end{eqnarray*}\r\nwhere \n(18)\r\n\\begin{eqnarray*}\r\n\\dot{\\boldsymbol {e}}_{\\hat{\\alpha }_1} \\simeq \\frac{\\hat{\\alpha }_1}{4c^2} \\, \\frac{M_{\\rm p}- M_{\\rm c}}{M_{\\rm p}+ M_{\\rm c}} \\, n_{\\rm b} \\mathcal {V}_O \\, {\\boldsymbol w}_\\perp \r\n\\end{eqnarray*}\r\n(Damour & Esposito-Farèse 1992b) and \n(19)\r\n\\begin{eqnarray*}\r\n\\dot{\\boldsymbol {e}}_{\\hat{\\alpha }_3} \\simeq \\frac{3}{2\\mathcal {V}_O}\\, {\\boldsymbol {a}}_{\\hat{\\alpha }_3} \\times \\hat{\\boldsymbol {k}} = -\\hat{\\alpha }_3 \\pi \\, \\frac{s_{\\rm p}\\nu }{\\mathcal {V}_O} \\, {\\boldsymbol w}_\\perp \r\n\\end{eqnarray*}\r\n(Bell & Damour 1996). The velocity ${\\boldsymbol w}$⊥ is the projection of the systemic CMB frame velocity into the orbital plane of the binary pulsar. To independently constrain $\\hat{\\alpha }_3$ from PSR J1713+0747 timing, we will include the $\\hat{\\alpha }_1$ limits obtained from PSR J1738+0333 by Shao & Wex (2012) in our analysis. Conversely, owing to its small orbital period, PSR J1738+0333’s possible $\\hat{\\alpha }_3$ effects would be much smaller than its $\\hat{\\alpha }_1$ effects and would have insignificant impact on the $\\hat{\\alpha }_1$ limits derived from this system. There is one assumption, however, that we have to make here. Since PSR J1713+0747 and PSR J1738+0333 have different masses, and therefore different sensitivities sp, we cannot assume that they would lead to identical $\\hat{\\alpha }_1$. For this reason, our analysis only applies to deviations from GR which exhibit only a moderate mass dependence of the strong-field parameter $\\hat{\\alpha }_1$, at least for neutron stars in the range of 1.3–1.5 M⊙.","Citation Text":["Damour & Esposito-Farèse 1992b"],"Citation Start End":[[651,681]]} {"Identifier":"2018ApJ...854...33Z__Esposito_&_Walter_2016_Instance_1","Paragraph":"In our spectroscopic analysis, we also quantify the reflection strength for each source. It is therefore interesting to compare our results to the typical assumptions made in CXB population-synthesis models. Indeed, they generally implement relatively similar assumptions. The reflection is always assumed to have a constant value \n\n\n\n\n\n within each population (e.g., Ballantyne et al. 2006; Treister et al. 2009; Akylas et al. 2012; Ueda et al. 2014) or possibly a function of the degree of obscuration (e.g., G07; Ueda et al. 2014; Esposito & Walter 2016) with no dispersion around a mean value. On average, we find median reflection values that are: (1) significantly lower (\n\n\n\n\n\n) than those assumed (\n\n\n\n\n\n) by CXB models and (2) exhibit a rather broad distribution with a median value relative to the whole sample of ∼0.4 (Table 6). Furthermore, we measure a significant anti-correlation with unabsorbed and intrinsic luminosities (the latter being more pronounced; see Figure 8 (lower panels) and Table 6). This trend is further confirmed by the findings of our companion paper on stacked NuSTAR spectra (DM17). In this context, we find sources with lower unabsorbed luminosities to have a median reflection (\n\n\n\n\n\n) a factor of two stronger than more luminous ones (\n\n\n\n\n\n). The broad R distribution reaches 50% percentile values a factor of two larger. When using intrinsic coronal luminosities, the differences exacerbates further by a factor of about two. A similar trend has been largely ignored by models; the one exception being the G07 model, for which QSOs have been assumed to have no reflection. G07 also assumes higher R for Type-1 sources (R = 1.3) compared to Type-2s (R = 0.88) in order to mimic a orientation-dependent disk reflection. Ueda et al. (2014) instead assumes a flat R = 0.5 from the disk and a torus-based contribution in the context of a luminosity- and redshift-dependent unified scenario in order to reproduce a total R = 1 for Seyfert galaxies.","Citation Text":["Esposito & Walter 2016"],"Citation Start End":[[534,556]]} {"Identifier":"2021ApJ...915...33S__Atek_et_al._2015_Instance_1","Paragraph":"Over the past decades, our understanding of the EoR has deepened from advances in the observational frontier of galaxies in the early universe. Dedicated surveys of high-redshift galaxies using the Hubble Space Telescope (HST) have measured a large sample of galaxies out to redshift as high as z ∼ 8 (Bouwens et al. 2015b; Finkelstein et al. 2015), which with the help of gravitational lensing has allowed the rest-frame ultraviolet (UV) galaxy luminosity function to be accurately constrained to a limiting magnitude of \n\n\n\n\n\n\nM\n\n\nUV\n\n\nAB\n\n\n≳\n−\n15\n\n\n (Atek et al. 2015; Bouwens et al. 2017; Yue et al. 2018). It is expected that, by the advent of the James Webb Space Telescope (JWST), not only the currently limited sample size of 9 ≲ z ≲ 12 galaxies and candidates (Ellis et al. 2013; Oesch et al. 2014, 2016, 2018) but also the constraints on the faint-end slope evolution of the UV luminosity function will be considerably enhanced (Mason et al. 2015; Yung et al. 2019). Combined with the Thomson scattering optical depth τes = 0.055 ± 0.009 inferred from the cosmic microwave background (CMB) temperature and polarization power spectra by Planck Collaboration et al. (2016a), the SFH based on a plausible faint-end extrapolation of the luminosity function suggests that the global reionization history could be explained by the “known” high-z galaxy population. If the average escape fraction of their ionizing photons into the intergalactic medium (IGM) is in the range of 10%–20% (e.g., Mason et al. 2015; Robertson et al. 2015; Bouwens et al. 2015a; Sun & Furlanetto 2016; Madau 2017; Naidu et al. 2020), there will be no need to invoke additional ionizing sources such as Population III stars and quasars. Nevertheless, the uncertainty associated with such an extrapolation indicates a fundamental limitation of surveys of individual objects—sources too faint compared with the instrument sensitivity, such as dwarf galaxies, are entirely missed by galaxy surveys, even though a significant fraction, if not the majority, of the ionizing photons are contributed by them (Wise et al. 2014; Trebitsch et al. 2018; but see also Naidu et al. 2020).","Citation Text":["Atek et al. 2015"],"Citation Start End":[[554,570]]} {"Identifier":"2021ApJ...923..206S__Galliano_et_al._2018_Instance_1","Paragraph":"Millimeter-to-submillimeter emission tells us much about these hidden galactic nuclei, for physical scales of several parsecs to several 100 pc in this work. First, these wavelengths contain various emission lines tracing the dominant (by mass) interstellar medium in these systems, that is, cold-to-warm molecular gas (∼10 to a few 100 K). The lines tell us the physical conditions and kinematics of the gas and thereby tell us about the fueling and feedback of the nuclear activities as well as the mass distribution in the nuclei. Second, the short millimeter and submillimeter continuum is usually dominated by thermal emission from dust. It is this dust continuum that carries the vast majority of the bolometric luminosity of these nuclei. Because of that, high-resolution information available at sub\/millimeter wavelengths is very useful to characterize the nuclei, complementing spatially unresolved observations at the far-IR where the continuum spectrum peaks. Third, the dust in these nuclei is moderately opaque (the opacity is around the order of unity) at sub\/millimeter wavelengths to produce bright emission, and yet it also makes the nuclei penetrable except at the very center in extreme cases. As a guide, τ\n1 mm = 1 corresponds to \n\n\n\nNH2∼1025.5\n\n cm−2 for an environment similar to the Galactic disk (Planck Collaboration et al. 2014; Galliano et al. 2018). The structure of the nuclei can thus be probed more easily in the sub\/millimeter than at far-IR and shorter wavelengths. At the same time, the continuum emission carries information about the dust opacity and hence the obscuring column density. Fourth, rotational lines from vibrationally excited HCN at sub\/millimeter wavelengths can be an indicator and probe of the NGC 4418\/Arp 220-type nuclei with significant obscuration (Sakamoto et al. 2009; Aalto et al. 2015, 2019; Imanishi et al. 2019). These nuclei are opaque enough to trap infrared photons to increase their inner temperature (i.e., the greenhouse effect), and the enhanced infrared radiation vibrationally excites molecules such as HCN (González-Alfonso & Sakamoto 2019). Their rotational lines in the sub\/millimeter have a chance to leak out of the dusty nuclei and indicate their hot interior since dust opacity is lower at longer wavelengths. And finally, the Atacama Large Millimeter\/submillimeter Array (ALMA) has dramatically enhanced our capability for high-resolution and high-sensitivity observations at sub\/millimeter wavelengths. A characteristic ALMA resolution of 0.″1 is on the order of 10 pc at nearby hidden galactic nuclei at tens of megaparsecs. While the resolution does not match the accretion disks around supermassive black holes (r ≪ 1 pc), it is only an order of magnitude larger than that of young massive star clusters (Longmore et al. 2014) and corresponds to the outer radii of molecular tori around AGN (Combes et al. 2019). Therefore, ALMA observations are good at probing the obscuring interstellar medium around AGN (if any), circumnuclear star formation, and their effects on the circumnuclear material.","Citation Text":["Galliano et al. 2018"],"Citation Start End":[[1357,1377]]} {"Identifier":"2022ApJ...926...76U__Venemans_et_al._2007_Instance_1","Paragraph":"We should examine whether our picture is consistent with previous studies at a higher radio luminosity regime, \n\n\n\nlogL1.4GHz>27\n\n. It is natural to assume that the unification between radio galaxies (HzRGs) and RLQSOs works at this regime. Actually, observational evidence for the unification has been found in this luminosity regime (Wylezalek et al. 2013). Hyperluminous radio galaxies\/RLQSOs with \n\n\n\nlogL1.4GHz>27\n\n are expected to reside in the galaxy denser regions according to the L\njet − Σ relation,\n16\n\n\n16\nThe L\njet − Σ relation would break down in the extremely high-density regions, as a very large velocity dispersion of galaxies in the massive structures reduces the merger frequency; thus, SMBH spin and mass growth would be slow. as shown by arrow \n\n\n\nC\n\n in Figure 7. There is definitive evidence that hyperluminous radio galaxies exist in the rich galaxy overdense regions (Venemans et al. 2007; Falder et al. 2010; Wylezalek et al. 2013; Hatch et al. 2014; Husband et al. 2016). For instance, Venemans et al. (2007) examined the environments of eight radio galaxies with log L\n1.4 GHz ≥ 27.3 at z ∼ 2−5 and found six of them in overdense regions. These radio galaxies with available optical spectra are classified as either HERGs, RLQSOs, or dust-obscured RLQSOs (Eales & Rawlings 1993; Venemans et al. 2007; Drouart et al. 2016; Nesvadba et al. 2017). Hatch et al. (2014) also found that radio-loud AGNs with log L\n1.4 GHz > 27.2 are significantly more present in high-density regions than radio-quiet AGNs at z ∼ 1−3. Falder et al. (2010) found that there is a positive correlation between the radio luminosities and the ambient environments of HzRGs and RLQSOs with log L\n1.4 GHz = 26.65–28.65 at z ∼ 1. A similar trend is also found for seven luminous radio galaxies at z ∼ 2.2 (Husband et al. 2016). The faintest radio galaxy with log L\n1.4 GHz = 26.6 in Husband et al. (2016) resides in the lowest-density region, which is comparable to that of blank fields (Figure 3), and the others with log L\n1.4 GHz > 27 reside in the denser regions. On the other hand, Zeballos et al. (2018) found that some of the HzRGs with log L\n1.4 GHz > 27 do not reside in the overdense regions of SMGs. However, Zeballos et al. (2018) could not deny the possibility that the overdense regions around those radio galaxies are buried due to the sample variance. In future, we could assess hyperluminous radio galaxy environments at z ∼ 4; as the survey area of the HSC-SSP will reach ∼1000 deg2, about 10 hyperluminous radio galaxies are expected to be found, assuming the radio galaxy luminosity function of Dunlop & Peacock (1990).","Citation Text":["Venemans et al. 2007"],"Citation Start End":[[894,914]]} {"Identifier":"2022ApJ...926...76U__Venemans_et_al._2007_Instance_2","Paragraph":"We should examine whether our picture is consistent with previous studies at a higher radio luminosity regime, \n\n\n\nlogL1.4GHz>27\n\n. It is natural to assume that the unification between radio galaxies (HzRGs) and RLQSOs works at this regime. Actually, observational evidence for the unification has been found in this luminosity regime (Wylezalek et al. 2013). Hyperluminous radio galaxies\/RLQSOs with \n\n\n\nlogL1.4GHz>27\n\n are expected to reside in the galaxy denser regions according to the L\njet − Σ relation,\n16\n\n\n16\nThe L\njet − Σ relation would break down in the extremely high-density regions, as a very large velocity dispersion of galaxies in the massive structures reduces the merger frequency; thus, SMBH spin and mass growth would be slow. as shown by arrow \n\n\n\nC\n\n in Figure 7. There is definitive evidence that hyperluminous radio galaxies exist in the rich galaxy overdense regions (Venemans et al. 2007; Falder et al. 2010; Wylezalek et al. 2013; Hatch et al. 2014; Husband et al. 2016). For instance, Venemans et al. (2007) examined the environments of eight radio galaxies with log L\n1.4 GHz ≥ 27.3 at z ∼ 2−5 and found six of them in overdense regions. These radio galaxies with available optical spectra are classified as either HERGs, RLQSOs, or dust-obscured RLQSOs (Eales & Rawlings 1993; Venemans et al. 2007; Drouart et al. 2016; Nesvadba et al. 2017). Hatch et al. (2014) also found that radio-loud AGNs with log L\n1.4 GHz > 27.2 are significantly more present in high-density regions than radio-quiet AGNs at z ∼ 1−3. Falder et al. (2010) found that there is a positive correlation between the radio luminosities and the ambient environments of HzRGs and RLQSOs with log L\n1.4 GHz = 26.65–28.65 at z ∼ 1. A similar trend is also found for seven luminous radio galaxies at z ∼ 2.2 (Husband et al. 2016). The faintest radio galaxy with log L\n1.4 GHz = 26.6 in Husband et al. (2016) resides in the lowest-density region, which is comparable to that of blank fields (Figure 3), and the others with log L\n1.4 GHz > 27 reside in the denser regions. On the other hand, Zeballos et al. (2018) found that some of the HzRGs with log L\n1.4 GHz > 27 do not reside in the overdense regions of SMGs. However, Zeballos et al. (2018) could not deny the possibility that the overdense regions around those radio galaxies are buried due to the sample variance. In future, we could assess hyperluminous radio galaxy environments at z ∼ 4; as the survey area of the HSC-SSP will reach ∼1000 deg2, about 10 hyperluminous radio galaxies are expected to be found, assuming the radio galaxy luminosity function of Dunlop & Peacock (1990).","Citation Text":["Venemans et al. (2007)"],"Citation Start End":[[1014,1036]]} {"Identifier":"2022ApJ...926...76U__Venemans_et_al._2007_Instance_3","Paragraph":"We should examine whether our picture is consistent with previous studies at a higher radio luminosity regime, \n\n\n\nlogL1.4GHz>27\n\n. It is natural to assume that the unification between radio galaxies (HzRGs) and RLQSOs works at this regime. Actually, observational evidence for the unification has been found in this luminosity regime (Wylezalek et al. 2013). Hyperluminous radio galaxies\/RLQSOs with \n\n\n\nlogL1.4GHz>27\n\n are expected to reside in the galaxy denser regions according to the L\njet − Σ relation,\n16\n\n\n16\nThe L\njet − Σ relation would break down in the extremely high-density regions, as a very large velocity dispersion of galaxies in the massive structures reduces the merger frequency; thus, SMBH spin and mass growth would be slow. as shown by arrow \n\n\n\nC\n\n in Figure 7. There is definitive evidence that hyperluminous radio galaxies exist in the rich galaxy overdense regions (Venemans et al. 2007; Falder et al. 2010; Wylezalek et al. 2013; Hatch et al. 2014; Husband et al. 2016). For instance, Venemans et al. (2007) examined the environments of eight radio galaxies with log L\n1.4 GHz ≥ 27.3 at z ∼ 2−5 and found six of them in overdense regions. These radio galaxies with available optical spectra are classified as either HERGs, RLQSOs, or dust-obscured RLQSOs (Eales & Rawlings 1993; Venemans et al. 2007; Drouart et al. 2016; Nesvadba et al. 2017). Hatch et al. (2014) also found that radio-loud AGNs with log L\n1.4 GHz > 27.2 are significantly more present in high-density regions than radio-quiet AGNs at z ∼ 1−3. Falder et al. (2010) found that there is a positive correlation between the radio luminosities and the ambient environments of HzRGs and RLQSOs with log L\n1.4 GHz = 26.65–28.65 at z ∼ 1. A similar trend is also found for seven luminous radio galaxies at z ∼ 2.2 (Husband et al. 2016). The faintest radio galaxy with log L\n1.4 GHz = 26.6 in Husband et al. (2016) resides in the lowest-density region, which is comparable to that of blank fields (Figure 3), and the others with log L\n1.4 GHz > 27 reside in the denser regions. On the other hand, Zeballos et al. (2018) found that some of the HzRGs with log L\n1.4 GHz > 27 do not reside in the overdense regions of SMGs. However, Zeballos et al. (2018) could not deny the possibility that the overdense regions around those radio galaxies are buried due to the sample variance. In future, we could assess hyperluminous radio galaxy environments at z ∼ 4; as the survey area of the HSC-SSP will reach ∼1000 deg2, about 10 hyperluminous radio galaxies are expected to be found, assuming the radio galaxy luminosity function of Dunlop & Peacock (1990).","Citation Text":["Venemans et al. 2007"],"Citation Start End":[[1308,1328]]} {"Identifier":"2020ApJ...903...56P__Parmentier_2019_Instance_1","Paragraph":"The SFR of a gaseous clump with a density gradient is higher than if that same clump was made of uniform-density gas (Tan et al. 2006; Girichidis et al. 2011; Elmegreen 2011; Parmentier 2014, 2019). Centrally concentrated clumps actually process their gas into stars at a pace faster than expected based on their mean freefall time, because the density of their central regions is higher than the clump gas mean density. Parmentier (2019) refers to the ratio between the SFR of a clump with a density gradient, SFRclump, and the SFR of its top-hat equivalent, SFRTH, as the magnification factor ζ (see Equation (8) in Parmentier 2019):\n1\n\n\n\n\n\nThe SFR of a clump can thus be written as (see Section 2 in Parmentier 2019, for a discussion)\n2\n\n\n\n\n\nIn this equation, mgas is the gas mass hosted by the clump,1\n\n1\nThe clump total mass mclump consists of the gas mass mgas and the mass mstars of the stars it has formed.\n and \n\n\n\n\n\n is the mean freefall time of the clump gas:\n3\n\n\n\n\n\nThe latter is defined based on the clump gas mean density\n4\n\n\n\n\n\nwith rclump the radius containing the clump gas mass mgas. ζ is the magnification factor, which quantifies by how much the density gradient of a clump enhances its SFR compared with what is expected based on its mean freefall time \n\n\n\n\n\n. Equation (2) therefore allows one to disentangle the contribution of the density gradient, embodied by the ζ factor, from that of the star formation efficiency per freefall time itself. Parmentier (2019) coins \n\n\n\n\n\n the intrinsic star formation efficiency per freefall time since it is independent of the clump density gradient.2\n\n2\nThis is as opposed to the (globally) measured star formation efficiency per freefall time, defined as \n\n\n\n\n\n (Parmentier 2019).\n For a top-hat profile, ζ = 1 and the SFR obeys\n5\n\n\n\n\n\nNote that the gas density of the top-hat equivalent is equal to the gas mean density \n\n\n\n\n\n of the centrally concentrated clump (same gas mass mgas enclosed within the same clump radius rclump).","Citation Text":["Parmentier","2019"],"Citation Start End":[[175,185],[192,196]]} {"Identifier":"2020ApJ...903...56P__Parmentier_2019_Instance_2","Paragraph":"The SFR of a gaseous clump with a density gradient is higher than if that same clump was made of uniform-density gas (Tan et al. 2006; Girichidis et al. 2011; Elmegreen 2011; Parmentier 2014, 2019). Centrally concentrated clumps actually process their gas into stars at a pace faster than expected based on their mean freefall time, because the density of their central regions is higher than the clump gas mean density. Parmentier (2019) refers to the ratio between the SFR of a clump with a density gradient, SFRclump, and the SFR of its top-hat equivalent, SFRTH, as the magnification factor ζ (see Equation (8) in Parmentier 2019):\n1\n\n\n\n\n\nThe SFR of a clump can thus be written as (see Section 2 in Parmentier 2019, for a discussion)\n2\n\n\n\n\n\nIn this equation, mgas is the gas mass hosted by the clump,1\n\n1\nThe clump total mass mclump consists of the gas mass mgas and the mass mstars of the stars it has formed.\n and \n\n\n\n\n\n is the mean freefall time of the clump gas:\n3\n\n\n\n\n\nThe latter is defined based on the clump gas mean density\n4\n\n\n\n\n\nwith rclump the radius containing the clump gas mass mgas. ζ is the magnification factor, which quantifies by how much the density gradient of a clump enhances its SFR compared with what is expected based on its mean freefall time \n\n\n\n\n\n. Equation (2) therefore allows one to disentangle the contribution of the density gradient, embodied by the ζ factor, from that of the star formation efficiency per freefall time itself. Parmentier (2019) coins \n\n\n\n\n\n the intrinsic star formation efficiency per freefall time since it is independent of the clump density gradient.2\n\n2\nThis is as opposed to the (globally) measured star formation efficiency per freefall time, defined as \n\n\n\n\n\n (Parmentier 2019).\n For a top-hat profile, ζ = 1 and the SFR obeys\n5\n\n\n\n\n\nNote that the gas density of the top-hat equivalent is equal to the gas mean density \n\n\n\n\n\n of the centrally concentrated clump (same gas mass mgas enclosed within the same clump radius rclump).","Citation Text":["Parmentier (2019)"],"Citation Start End":[[421,438]]} {"Identifier":"2020ApJ...903...56P__Parmentier_2019_Instance_3","Paragraph":"The SFR of a gaseous clump with a density gradient is higher than if that same clump was made of uniform-density gas (Tan et al. 2006; Girichidis et al. 2011; Elmegreen 2011; Parmentier 2014, 2019). Centrally concentrated clumps actually process their gas into stars at a pace faster than expected based on their mean freefall time, because the density of their central regions is higher than the clump gas mean density. Parmentier (2019) refers to the ratio between the SFR of a clump with a density gradient, SFRclump, and the SFR of its top-hat equivalent, SFRTH, as the magnification factor ζ (see Equation (8) in Parmentier 2019):\n1\n\n\n\n\n\nThe SFR of a clump can thus be written as (see Section 2 in Parmentier 2019, for a discussion)\n2\n\n\n\n\n\nIn this equation, mgas is the gas mass hosted by the clump,1\n\n1\nThe clump total mass mclump consists of the gas mass mgas and the mass mstars of the stars it has formed.\n and \n\n\n\n\n\n is the mean freefall time of the clump gas:\n3\n\n\n\n\n\nThe latter is defined based on the clump gas mean density\n4\n\n\n\n\n\nwith rclump the radius containing the clump gas mass mgas. ζ is the magnification factor, which quantifies by how much the density gradient of a clump enhances its SFR compared with what is expected based on its mean freefall time \n\n\n\n\n\n. Equation (2) therefore allows one to disentangle the contribution of the density gradient, embodied by the ζ factor, from that of the star formation efficiency per freefall time itself. Parmentier (2019) coins \n\n\n\n\n\n the intrinsic star formation efficiency per freefall time since it is independent of the clump density gradient.2\n\n2\nThis is as opposed to the (globally) measured star formation efficiency per freefall time, defined as \n\n\n\n\n\n (Parmentier 2019).\n For a top-hat profile, ζ = 1 and the SFR obeys\n5\n\n\n\n\n\nNote that the gas density of the top-hat equivalent is equal to the gas mean density \n\n\n\n\n\n of the centrally concentrated clump (same gas mass mgas enclosed within the same clump radius rclump).","Citation Text":["Parmentier 2019"],"Citation Start End":[[618,633]]} {"Identifier":"2020ApJ...903...56P__Parmentier_2019_Instance_4","Paragraph":"The SFR of a gaseous clump with a density gradient is higher than if that same clump was made of uniform-density gas (Tan et al. 2006; Girichidis et al. 2011; Elmegreen 2011; Parmentier 2014, 2019). Centrally concentrated clumps actually process their gas into stars at a pace faster than expected based on their mean freefall time, because the density of their central regions is higher than the clump gas mean density. Parmentier (2019) refers to the ratio between the SFR of a clump with a density gradient, SFRclump, and the SFR of its top-hat equivalent, SFRTH, as the magnification factor ζ (see Equation (8) in Parmentier 2019):\n1\n\n\n\n\n\nThe SFR of a clump can thus be written as (see Section 2 in Parmentier 2019, for a discussion)\n2\n\n\n\n\n\nIn this equation, mgas is the gas mass hosted by the clump,1\n\n1\nThe clump total mass mclump consists of the gas mass mgas and the mass mstars of the stars it has formed.\n and \n\n\n\n\n\n is the mean freefall time of the clump gas:\n3\n\n\n\n\n\nThe latter is defined based on the clump gas mean density\n4\n\n\n\n\n\nwith rclump the radius containing the clump gas mass mgas. ζ is the magnification factor, which quantifies by how much the density gradient of a clump enhances its SFR compared with what is expected based on its mean freefall time \n\n\n\n\n\n. Equation (2) therefore allows one to disentangle the contribution of the density gradient, embodied by the ζ factor, from that of the star formation efficiency per freefall time itself. Parmentier (2019) coins \n\n\n\n\n\n the intrinsic star formation efficiency per freefall time since it is independent of the clump density gradient.2\n\n2\nThis is as opposed to the (globally) measured star formation efficiency per freefall time, defined as \n\n\n\n\n\n (Parmentier 2019).\n For a top-hat profile, ζ = 1 and the SFR obeys\n5\n\n\n\n\n\nNote that the gas density of the top-hat equivalent is equal to the gas mean density \n\n\n\n\n\n of the centrally concentrated clump (same gas mass mgas enclosed within the same clump radius rclump).","Citation Text":["Parmentier 2019"],"Citation Start End":[[703,718]]} {"Identifier":"2020ApJ...903...56P__Parmentier_2019_Instance_5","Paragraph":"The SFR of a gaseous clump with a density gradient is higher than if that same clump was made of uniform-density gas (Tan et al. 2006; Girichidis et al. 2011; Elmegreen 2011; Parmentier 2014, 2019). Centrally concentrated clumps actually process their gas into stars at a pace faster than expected based on their mean freefall time, because the density of their central regions is higher than the clump gas mean density. Parmentier (2019) refers to the ratio between the SFR of a clump with a density gradient, SFRclump, and the SFR of its top-hat equivalent, SFRTH, as the magnification factor ζ (see Equation (8) in Parmentier 2019):\n1\n\n\n\n\n\nThe SFR of a clump can thus be written as (see Section 2 in Parmentier 2019, for a discussion)\n2\n\n\n\n\n\nIn this equation, mgas is the gas mass hosted by the clump,1\n\n1\nThe clump total mass mclump consists of the gas mass mgas and the mass mstars of the stars it has formed.\n and \n\n\n\n\n\n is the mean freefall time of the clump gas:\n3\n\n\n\n\n\nThe latter is defined based on the clump gas mean density\n4\n\n\n\n\n\nwith rclump the radius containing the clump gas mass mgas. ζ is the magnification factor, which quantifies by how much the density gradient of a clump enhances its SFR compared with what is expected based on its mean freefall time \n\n\n\n\n\n. Equation (2) therefore allows one to disentangle the contribution of the density gradient, embodied by the ζ factor, from that of the star formation efficiency per freefall time itself. Parmentier (2019) coins \n\n\n\n\n\n the intrinsic star formation efficiency per freefall time since it is independent of the clump density gradient.2\n\n2\nThis is as opposed to the (globally) measured star formation efficiency per freefall time, defined as \n\n\n\n\n\n (Parmentier 2019).\n For a top-hat profile, ζ = 1 and the SFR obeys\n5\n\n\n\n\n\nNote that the gas density of the top-hat equivalent is equal to the gas mean density \n\n\n\n\n\n of the centrally concentrated clump (same gas mass mgas enclosed within the same clump radius rclump).","Citation Text":["Parmentier (2019)"],"Citation Start End":[[1468,1485]]} {"Identifier":"2020ApJ...903...56P__Parmentier_2019_Instance_6","Paragraph":"The SFR of a gaseous clump with a density gradient is higher than if that same clump was made of uniform-density gas (Tan et al. 2006; Girichidis et al. 2011; Elmegreen 2011; Parmentier 2014, 2019). Centrally concentrated clumps actually process their gas into stars at a pace faster than expected based on their mean freefall time, because the density of their central regions is higher than the clump gas mean density. Parmentier (2019) refers to the ratio between the SFR of a clump with a density gradient, SFRclump, and the SFR of its top-hat equivalent, SFRTH, as the magnification factor ζ (see Equation (8) in Parmentier 2019):\n1\n\n\n\n\n\nThe SFR of a clump can thus be written as (see Section 2 in Parmentier 2019, for a discussion)\n2\n\n\n\n\n\nIn this equation, mgas is the gas mass hosted by the clump,1\n\n1\nThe clump total mass mclump consists of the gas mass mgas and the mass mstars of the stars it has formed.\n and \n\n\n\n\n\n is the mean freefall time of the clump gas:\n3\n\n\n\n\n\nThe latter is defined based on the clump gas mean density\n4\n\n\n\n\n\nwith rclump the radius containing the clump gas mass mgas. ζ is the magnification factor, which quantifies by how much the density gradient of a clump enhances its SFR compared with what is expected based on its mean freefall time \n\n\n\n\n\n. Equation (2) therefore allows one to disentangle the contribution of the density gradient, embodied by the ζ factor, from that of the star formation efficiency per freefall time itself. Parmentier (2019) coins \n\n\n\n\n\n the intrinsic star formation efficiency per freefall time since it is independent of the clump density gradient.2\n\n2\nThis is as opposed to the (globally) measured star formation efficiency per freefall time, defined as \n\n\n\n\n\n (Parmentier 2019).\n For a top-hat profile, ζ = 1 and the SFR obeys\n5\n\n\n\n\n\nNote that the gas density of the top-hat equivalent is equal to the gas mean density \n\n\n\n\n\n of the centrally concentrated clump (same gas mass mgas enclosed within the same clump radius rclump).","Citation Text":["Parmentier 2019"],"Citation Start End":[[1726,1741]]} {"Identifier":"2017ApJ...850...77K__Henshaw_et_al._2016a_Instance_1","Paragraph":"Various models of the gas and dust distribution in the GC exist: a simple bar model (Morris & Serabyn 1996); variations of a spiral arm model in which the apparent ring is formed by the inner part of two spiral arms (Sofue 1995; Sawada et al. 2004; Rodríguez-Fernández & Combes 2008; Rodríguez-Fernández 2011; Ridley et al. 2017); a closed, twisted elliptical ring detected in dust emission (Molinari et al. 2011), and a sequence of open-ended gas streams (Kruijssen et al. 2015, hereafter K15). K15 highlight the impossibility of closed orbits in extended gravitational potentials and provide a better fit to single-dish ammonia emission in position–position–velocity (PPV) space, as was confirmed by Henshaw et al. (2016b) for three molecular species in single-dish observations. Thus, we focus on this model and call it the “stream model” in contrast to the “ring model” and the “spiral arm” model. According to the stream model, the stream of GC molecular clouds oscillates radially and vertically, and can be traced for ∼1.5 revolutions around the GC. The radial oscillation periodically brings dense molecular gas closer (r ∼ 60 pc at pericenter) to the gravitational center (traced by Sgr A*) and deeper into the potential, whereas the apocenter lies at r ∼ 120 pc. As the CMZ clouds slowly evolve toward low virial ratios as the turbulent energy dissipates (Krumholz & Kruijssen 2015; Walker et al. 2015; Henshaw et al. 2016a), it is statistically more likely that cloud collapse occurs at the pericenter where the compressive tidal forces are strongest along the orbit and thus a cloud receives the final nudge for the transition to self-gravitation. Subsequent SF stages will then occur downstream from the pericenter passages and could potentially be observed as an SF sequence if the orbit is sufficiently sampled with molecular clouds that start to collapse at a similar point of their orbits. This model of triggered star formation was first proposed by Longmore et al. (2013b) based on the observation of different evolutionary SF stages along the dust ridge. The two young stellar clusters in the GC, Arches and Quintuplet, may also support this model as their orbits and ages are consistent with formation at a common point after collapse of their respective parent clouds at a pericenter passage (Figure 1 of Stolte et al. 2014; Kruijssen et al. 2015). In addition to stars and star formation tracers, cloud properties are also expected to show evolutionary behavior along the gas streams; this has not been thoroughly tested yet. Weak hints toward rising gas temperatures in the dust ridge are suggested by Ginsburg et al. (2016), while a recent paper by Kauffmann et al. (2017b) based on N2H+ data from the Galactic Center Molecular Cloud Survey can neither confirm nor exclude the possibility of triggered evolution when examining mass-size relation and SF suppression. Both analyses were based on a low number of measurements (∼35 measurements in dust ridge clouds in Ginsburg et al. 2016 and six clouds in Kauffmann et al. 2017b) and lack the statistical power to detect potential evolution in the presence of scatter.","Citation Text":["Henshaw et al. 2016a"],"Citation Start End":[[1413,1433]]} {"Identifier":"2017ApJ...850...77KMolinari_et_al._2011_Instance_1","Paragraph":"Various models of the gas and dust distribution in the GC exist: a simple bar model (Morris & Serabyn 1996); variations of a spiral arm model in which the apparent ring is formed by the inner part of two spiral arms (Sofue 1995; Sawada et al. 2004; Rodríguez-Fernández & Combes 2008; Rodríguez-Fernández 2011; Ridley et al. 2017); a closed, twisted elliptical ring detected in dust emission (Molinari et al. 2011), and a sequence of open-ended gas streams (Kruijssen et al. 2015, hereafter K15). K15 highlight the impossibility of closed orbits in extended gravitational potentials and provide a better fit to single-dish ammonia emission in position–position–velocity (PPV) space, as was confirmed by Henshaw et al. (2016b) for three molecular species in single-dish observations. Thus, we focus on this model and call it the “stream model” in contrast to the “ring model” and the “spiral arm” model. According to the stream model, the stream of GC molecular clouds oscillates radially and vertically, and can be traced for ∼1.5 revolutions around the GC. The radial oscillation periodically brings dense molecular gas closer (r ∼ 60 pc at pericenter) to the gravitational center (traced by Sgr A*) and deeper into the potential, whereas the apocenter lies at r ∼ 120 pc. As the CMZ clouds slowly evolve toward low virial ratios as the turbulent energy dissipates (Krumholz & Kruijssen 2015; Walker et al. 2015; Henshaw et al. 2016a), it is statistically more likely that cloud collapse occurs at the pericenter where the compressive tidal forces are strongest along the orbit and thus a cloud receives the final nudge for the transition to self-gravitation. Subsequent SF stages will then occur downstream from the pericenter passages and could potentially be observed as an SF sequence if the orbit is sufficiently sampled with molecular clouds that start to collapse at a similar point of their orbits. This model of triggered star formation was first proposed by Longmore et al. (2013b) based on the observation of different evolutionary SF stages along the dust ridge. The two young stellar clusters in the GC, Arches and Quintuplet, may also support this model as their orbits and ages are consistent with formation at a common point after collapse of their respective parent clouds at a pericenter passage (Figure 1 of Stolte et al. 2014; Kruijssen et al. 2015). In addition to stars and star formation tracers, cloud properties are also expected to show evolutionary behavior along the gas streams; this has not been thoroughly tested yet. Weak hints toward rising gas temperatures in the dust ridge are suggested by Ginsburg et al. (2016), while a recent paper by Kauffmann et al. (2017b) based on N2H+ data from the Galactic Center Molecular Cloud Survey can neither confirm nor exclude the possibility of triggered evolution when examining mass-size relation and SF suppression. Both analyses were based on a low number of measurements (∼35 measurements in dust ridge clouds in Ginsburg et al. 2016 and six clouds in Kauffmann et al. 2017b) and lack the statistical power to detect potential evolution in the presence of scatter.","Citation Text":["Molinari et al. 2011"],"Citation Start End":[[392,412]]} {"Identifier":"2017ApJ...850...77KLongmore_et_al._(2013b)_Instance_1","Paragraph":"Various models of the gas and dust distribution in the GC exist: a simple bar model (Morris & Serabyn 1996); variations of a spiral arm model in which the apparent ring is formed by the inner part of two spiral arms (Sofue 1995; Sawada et al. 2004; Rodríguez-Fernández & Combes 2008; Rodríguez-Fernández 2011; Ridley et al. 2017); a closed, twisted elliptical ring detected in dust emission (Molinari et al. 2011), and a sequence of open-ended gas streams (Kruijssen et al. 2015, hereafter K15). K15 highlight the impossibility of closed orbits in extended gravitational potentials and provide a better fit to single-dish ammonia emission in position–position–velocity (PPV) space, as was confirmed by Henshaw et al. (2016b) for three molecular species in single-dish observations. Thus, we focus on this model and call it the “stream model” in contrast to the “ring model” and the “spiral arm” model. According to the stream model, the stream of GC molecular clouds oscillates radially and vertically, and can be traced for ∼1.5 revolutions around the GC. The radial oscillation periodically brings dense molecular gas closer (r ∼ 60 pc at pericenter) to the gravitational center (traced by Sgr A*) and deeper into the potential, whereas the apocenter lies at r ∼ 120 pc. As the CMZ clouds slowly evolve toward low virial ratios as the turbulent energy dissipates (Krumholz & Kruijssen 2015; Walker et al. 2015; Henshaw et al. 2016a), it is statistically more likely that cloud collapse occurs at the pericenter where the compressive tidal forces are strongest along the orbit and thus a cloud receives the final nudge for the transition to self-gravitation. Subsequent SF stages will then occur downstream from the pericenter passages and could potentially be observed as an SF sequence if the orbit is sufficiently sampled with molecular clouds that start to collapse at a similar point of their orbits. This model of triggered star formation was first proposed by Longmore et al. (2013b) based on the observation of different evolutionary SF stages along the dust ridge. The two young stellar clusters in the GC, Arches and Quintuplet, may also support this model as their orbits and ages are consistent with formation at a common point after collapse of their respective parent clouds at a pericenter passage (Figure 1 of Stolte et al. 2014; Kruijssen et al. 2015). In addition to stars and star formation tracers, cloud properties are also expected to show evolutionary behavior along the gas streams; this has not been thoroughly tested yet. Weak hints toward rising gas temperatures in the dust ridge are suggested by Ginsburg et al. (2016), while a recent paper by Kauffmann et al. (2017b) based on N2H+ data from the Galactic Center Molecular Cloud Survey can neither confirm nor exclude the possibility of triggered evolution when examining mass-size relation and SF suppression. Both analyses were based on a low number of measurements (∼35 measurements in dust ridge clouds in Ginsburg et al. 2016 and six clouds in Kauffmann et al. 2017b) and lack the statistical power to detect potential evolution in the presence of scatter.","Citation Text":["Longmore et al. (2013b)"],"Citation Start End":[[1968,1991]]} {"Identifier":"2017ApJ...850...77KStolte_et_al._2014_Instance_1","Paragraph":"Various models of the gas and dust distribution in the GC exist: a simple bar model (Morris & Serabyn 1996); variations of a spiral arm model in which the apparent ring is formed by the inner part of two spiral arms (Sofue 1995; Sawada et al. 2004; Rodríguez-Fernández & Combes 2008; Rodríguez-Fernández 2011; Ridley et al. 2017); a closed, twisted elliptical ring detected in dust emission (Molinari et al. 2011), and a sequence of open-ended gas streams (Kruijssen et al. 2015, hereafter K15). K15 highlight the impossibility of closed orbits in extended gravitational potentials and provide a better fit to single-dish ammonia emission in position–position–velocity (PPV) space, as was confirmed by Henshaw et al. (2016b) for three molecular species in single-dish observations. Thus, we focus on this model and call it the “stream model” in contrast to the “ring model” and the “spiral arm” model. According to the stream model, the stream of GC molecular clouds oscillates radially and vertically, and can be traced for ∼1.5 revolutions around the GC. The radial oscillation periodically brings dense molecular gas closer (r ∼ 60 pc at pericenter) to the gravitational center (traced by Sgr A*) and deeper into the potential, whereas the apocenter lies at r ∼ 120 pc. As the CMZ clouds slowly evolve toward low virial ratios as the turbulent energy dissipates (Krumholz & Kruijssen 2015; Walker et al. 2015; Henshaw et al. 2016a), it is statistically more likely that cloud collapse occurs at the pericenter where the compressive tidal forces are strongest along the orbit and thus a cloud receives the final nudge for the transition to self-gravitation. Subsequent SF stages will then occur downstream from the pericenter passages and could potentially be observed as an SF sequence if the orbit is sufficiently sampled with molecular clouds that start to collapse at a similar point of their orbits. This model of triggered star formation was first proposed by Longmore et al. (2013b) based on the observation of different evolutionary SF stages along the dust ridge. The two young stellar clusters in the GC, Arches and Quintuplet, may also support this model as their orbits and ages are consistent with formation at a common point after collapse of their respective parent clouds at a pericenter passage (Figure 1 of Stolte et al. 2014; Kruijssen et al. 2015). In addition to stars and star formation tracers, cloud properties are also expected to show evolutionary behavior along the gas streams; this has not been thoroughly tested yet. Weak hints toward rising gas temperatures in the dust ridge are suggested by Ginsburg et al. (2016), while a recent paper by Kauffmann et al. (2017b) based on N2H+ data from the Galactic Center Molecular Cloud Survey can neither confirm nor exclude the possibility of triggered evolution when examining mass-size relation and SF suppression. Both analyses were based on a low number of measurements (∼35 measurements in dust ridge clouds in Ginsburg et al. 2016 and six clouds in Kauffmann et al. 2017b) and lack the statistical power to detect potential evolution in the presence of scatter.","Citation Text":["Stolte et al. 2014"],"Citation Start End":[[2327,2345]]} {"Identifier":"2017ApJ...850...77KKauffmann_et_al._(2017b)_Instance_1","Paragraph":"Various models of the gas and dust distribution in the GC exist: a simple bar model (Morris & Serabyn 1996); variations of a spiral arm model in which the apparent ring is formed by the inner part of two spiral arms (Sofue 1995; Sawada et al. 2004; Rodríguez-Fernández & Combes 2008; Rodríguez-Fernández 2011; Ridley et al. 2017); a closed, twisted elliptical ring detected in dust emission (Molinari et al. 2011), and a sequence of open-ended gas streams (Kruijssen et al. 2015, hereafter K15). K15 highlight the impossibility of closed orbits in extended gravitational potentials and provide a better fit to single-dish ammonia emission in position–position–velocity (PPV) space, as was confirmed by Henshaw et al. (2016b) for three molecular species in single-dish observations. Thus, we focus on this model and call it the “stream model” in contrast to the “ring model” and the “spiral arm” model. According to the stream model, the stream of GC molecular clouds oscillates radially and vertically, and can be traced for ∼1.5 revolutions around the GC. The radial oscillation periodically brings dense molecular gas closer (r ∼ 60 pc at pericenter) to the gravitational center (traced by Sgr A*) and deeper into the potential, whereas the apocenter lies at r ∼ 120 pc. As the CMZ clouds slowly evolve toward low virial ratios as the turbulent energy dissipates (Krumholz & Kruijssen 2015; Walker et al. 2015; Henshaw et al. 2016a), it is statistically more likely that cloud collapse occurs at the pericenter where the compressive tidal forces are strongest along the orbit and thus a cloud receives the final nudge for the transition to self-gravitation. Subsequent SF stages will then occur downstream from the pericenter passages and could potentially be observed as an SF sequence if the orbit is sufficiently sampled with molecular clouds that start to collapse at a similar point of their orbits. This model of triggered star formation was first proposed by Longmore et al. (2013b) based on the observation of different evolutionary SF stages along the dust ridge. The two young stellar clusters in the GC, Arches and Quintuplet, may also support this model as their orbits and ages are consistent with formation at a common point after collapse of their respective parent clouds at a pericenter passage (Figure 1 of Stolte et al. 2014; Kruijssen et al. 2015). In addition to stars and star formation tracers, cloud properties are also expected to show evolutionary behavior along the gas streams; this has not been thoroughly tested yet. Weak hints toward rising gas temperatures in the dust ridge are suggested by Ginsburg et al. (2016), while a recent paper by Kauffmann et al. (2017b) based on N2H+ data from the Galactic Center Molecular Cloud Survey can neither confirm nor exclude the possibility of triggered evolution when examining mass-size relation and SF suppression. Both analyses were based on a low number of measurements (∼35 measurements in dust ridge clouds in Ginsburg et al. 2016 and six clouds in Kauffmann et al. 2017b) and lack the statistical power to detect potential evolution in the presence of scatter.","Citation Text":["Kauffmann et al. (2017b)"],"Citation Start End":[[2674,2698]]} {"Identifier":"2017ApJ...850...77KKauffmann_et_al._2017b_Instance_2","Paragraph":"Various models of the gas and dust distribution in the GC exist: a simple bar model (Morris & Serabyn 1996); variations of a spiral arm model in which the apparent ring is formed by the inner part of two spiral arms (Sofue 1995; Sawada et al. 2004; Rodríguez-Fernández & Combes 2008; Rodríguez-Fernández 2011; Ridley et al. 2017); a closed, twisted elliptical ring detected in dust emission (Molinari et al. 2011), and a sequence of open-ended gas streams (Kruijssen et al. 2015, hereafter K15). K15 highlight the impossibility of closed orbits in extended gravitational potentials and provide a better fit to single-dish ammonia emission in position–position–velocity (PPV) space, as was confirmed by Henshaw et al. (2016b) for three molecular species in single-dish observations. Thus, we focus on this model and call it the “stream model” in contrast to the “ring model” and the “spiral arm” model. According to the stream model, the stream of GC molecular clouds oscillates radially and vertically, and can be traced for ∼1.5 revolutions around the GC. The radial oscillation periodically brings dense molecular gas closer (r ∼ 60 pc at pericenter) to the gravitational center (traced by Sgr A*) and deeper into the potential, whereas the apocenter lies at r ∼ 120 pc. As the CMZ clouds slowly evolve toward low virial ratios as the turbulent energy dissipates (Krumholz & Kruijssen 2015; Walker et al. 2015; Henshaw et al. 2016a), it is statistically more likely that cloud collapse occurs at the pericenter where the compressive tidal forces are strongest along the orbit and thus a cloud receives the final nudge for the transition to self-gravitation. Subsequent SF stages will then occur downstream from the pericenter passages and could potentially be observed as an SF sequence if the orbit is sufficiently sampled with molecular clouds that start to collapse at a similar point of their orbits. This model of triggered star formation was first proposed by Longmore et al. (2013b) based on the observation of different evolutionary SF stages along the dust ridge. The two young stellar clusters in the GC, Arches and Quintuplet, may also support this model as their orbits and ages are consistent with formation at a common point after collapse of their respective parent clouds at a pericenter passage (Figure 1 of Stolte et al. 2014; Kruijssen et al. 2015). In addition to stars and star formation tracers, cloud properties are also expected to show evolutionary behavior along the gas streams; this has not been thoroughly tested yet. Weak hints toward rising gas temperatures in the dust ridge are suggested by Ginsburg et al. (2016), while a recent paper by Kauffmann et al. (2017b) based on N2H+ data from the Galactic Center Molecular Cloud Survey can neither confirm nor exclude the possibility of triggered evolution when examining mass-size relation and SF suppression. Both analyses were based on a low number of measurements (∼35 measurements in dust ridge clouds in Ginsburg et al. 2016 and six clouds in Kauffmann et al. 2017b) and lack the statistical power to detect potential evolution in the presence of scatter.","Citation Text":["Kauffmann et al. 2017b"],"Citation Start End":[[3029,3051]]} {"Identifier":"2016ApJ...829...99F__Izotov_et_al._2016a_Instance_1","Paragraph":"With only \n\n\n\n\n\n as a free parameter, different studies suggest that \n\n\n\n\n\n = 10%–20% at z > 6 is necessary for galaxies to fully ionize the universe (Bolton & Haehnelt 2007b; Finkelstein et al. 2012; Kuhlen & Faucher-Giguère 2012; Bouwens et al. 2015a, 2015c; Mitra et al. 2015; Robertson et al. 2015; Khaire et al. 2016; Price et al. 2016). Simulations do not agree on \n\n\n\n\n\n at high redshifts and find either very high (e.g., Sharma et al. 2016) or very low values (e.g., Gnedin et al. 2008; Ma et al. 2015). Furthermore, they predict a strong dependence on the mass of dark matter halos and star formation (e.g., Wise & Cen 2009; Razoumov & Sommer-Larsen 2010). Direct observational constraints on \n\n\n\n\n\n in the EoR are not possible because of the increasing opacity of the IGM to LyC photons at z > 4 (e.g., Madau 1995; Inoue et al. 2014). Except for one strong LyC emitter at z = 3.2 with \n\n\n\n\n\n > 50% (de Barros et al. 2016; Vanzella et al. 2016b), the handful of confirmed LyC emitters at z 3 all show consistently \n\n\n\n\n\n ≲ 8% (Steidel et al. 2001; Leitet et al. 2013; Borthakur et al. 2014; Cooke et al. 2014; Siana et al. 2015; Izotov et al. 2016a, 2016b; Leitherer et al. 2016; Smith et al. 2016). The numerous non-detections listed in the literature show upper limits of \n\n\n\n\n\n ∼ 2%–5% over large ranges of redshift (Vanzella et al. 2010; Sandberg et al. 2015; Grazian et al. 2016; Guaita et al. 2016; Rutkowski et al. 2016; Vasei et al. 2016). If galaxies are responsible for ionizing the universe at z > 6, then clearly their population-averaged LyC escape fraction needs to increase substantially with redshift by at least a factor of two (see also Inoue et al. 2006). What methods can we use to access \n\n\n\n\n\n observationally in the EoR? Radiative transfer models suggest a correlation between the ratio \n\n\n\n\n\n\/\n\n\n\n\n\n and \n\n\n\n\n\n in density-bound H ii regions (e.g., Nakajima & Ouchi 2014), and a handful of recent observational studies verify this positive correlation (de Barros et al. 2016; Izotov et al. 2016a, 2016b; Vanzella et al. 2016a, 2016b). The increased \n\n\n\n\n\n\/Hβ ratios found in z > 5 galaxies (e.g., Stanway et al. 2014; Roberts-Borsani et al. 2015; Faisst et al. 2016a) hint toward an increasing \n\n\n\n\n\n\/\n\n\n\n\n\n ratio for the global population of galaxies at high redshifts and therefore could be the smoking gun for a strong evolution in \n\n\n\n\n\n(z). Currently, the \n\n\n\n\n\n line cannot be measured spectroscopically at z > 4, and the use of broad-band photometry to determine \n\n\n\n\n\n line strengths is degenerate with the 4000 Å Balmer break, which is a strong function of age and other galaxy parameters. However, local analogs of high-redshift galaxies can be used to probe the physical properties of these galaxies.","Citation Text":["Izotov et al. 2016a"],"Citation Start End":[[1139,1158]]} {"Identifier":"2016ApJ...829...99F__Izotov_et_al._2016a_Instance_2","Paragraph":"With only \n\n\n\n\n\n as a free parameter, different studies suggest that \n\n\n\n\n\n = 10%–20% at z > 6 is necessary for galaxies to fully ionize the universe (Bolton & Haehnelt 2007b; Finkelstein et al. 2012; Kuhlen & Faucher-Giguère 2012; Bouwens et al. 2015a, 2015c; Mitra et al. 2015; Robertson et al. 2015; Khaire et al. 2016; Price et al. 2016). Simulations do not agree on \n\n\n\n\n\n at high redshifts and find either very high (e.g., Sharma et al. 2016) or very low values (e.g., Gnedin et al. 2008; Ma et al. 2015). Furthermore, they predict a strong dependence on the mass of dark matter halos and star formation (e.g., Wise & Cen 2009; Razoumov & Sommer-Larsen 2010). Direct observational constraints on \n\n\n\n\n\n in the EoR are not possible because of the increasing opacity of the IGM to LyC photons at z > 4 (e.g., Madau 1995; Inoue et al. 2014). Except for one strong LyC emitter at z = 3.2 with \n\n\n\n\n\n > 50% (de Barros et al. 2016; Vanzella et al. 2016b), the handful of confirmed LyC emitters at z 3 all show consistently \n\n\n\n\n\n ≲ 8% (Steidel et al. 2001; Leitet et al. 2013; Borthakur et al. 2014; Cooke et al. 2014; Siana et al. 2015; Izotov et al. 2016a, 2016b; Leitherer et al. 2016; Smith et al. 2016). The numerous non-detections listed in the literature show upper limits of \n\n\n\n\n\n ∼ 2%–5% over large ranges of redshift (Vanzella et al. 2010; Sandberg et al. 2015; Grazian et al. 2016; Guaita et al. 2016; Rutkowski et al. 2016; Vasei et al. 2016). If galaxies are responsible for ionizing the universe at z > 6, then clearly their population-averaged LyC escape fraction needs to increase substantially with redshift by at least a factor of two (see also Inoue et al. 2006). What methods can we use to access \n\n\n\n\n\n observationally in the EoR? Radiative transfer models suggest a correlation between the ratio \n\n\n\n\n\n\/\n\n\n\n\n\n and \n\n\n\n\n\n in density-bound H ii regions (e.g., Nakajima & Ouchi 2014), and a handful of recent observational studies verify this positive correlation (de Barros et al. 2016; Izotov et al. 2016a, 2016b; Vanzella et al. 2016a, 2016b). The increased \n\n\n\n\n\n\/Hβ ratios found in z > 5 galaxies (e.g., Stanway et al. 2014; Roberts-Borsani et al. 2015; Faisst et al. 2016a) hint toward an increasing \n\n\n\n\n\n\/\n\n\n\n\n\n ratio for the global population of galaxies at high redshifts and therefore could be the smoking gun for a strong evolution in \n\n\n\n\n\n(z). Currently, the \n\n\n\n\n\n line cannot be measured spectroscopically at z > 4, and the use of broad-band photometry to determine \n\n\n\n\n\n line strengths is degenerate with the 4000 Å Balmer break, which is a strong function of age and other galaxy parameters. However, local analogs of high-redshift galaxies can be used to probe the physical properties of these galaxies.","Citation Text":["Izotov et al. 2016a"],"Citation Start End":[[2009,2028]]} {"Identifier":"2022ApJ...934...85A__in_2011_Instance_1","Paragraph":"To detect supernova neutrinos with the KamLAND data, a cluster of DC events is required: two DC events within a 10 s window. The very low DC rate enables us to use the minimum cluster condition (two DC events). An accidental DC event cluster is a background for supernova neutrinos. Based on the DC event studies, we evaluate the number of accidental cluster events (\n\n\n\n≡nclusteraccidental\n\n) via Monte-Carlo (MC) simulation. Accidental cluster rates and accumulation of \n\n\n\nnclusteraccidental\n\n are shown in Figure 1. Before distillation campaigns, the DC event is mainly caused by reactor -\n\n\n\nν¯e\n\n, and 13C(α, n)16O interaction has a secondary contribution (Abe et al. 2008). After distillation campaigns, the DC event by 13C(α, n)16O interaction decreases but reactor -\n\n\n\nν¯e\n\n is still a dominant component (Gando et al. 2011). Japanese reactors were shut down after the Great East Japan Earthquake in 2011. In the reactor-off phase (Gando et al. 2013), the rate of reactor -\n\n\n\nν¯e\n\n events is decreased. These trends of DC event rate are also shown in Figure 1. In an energy region above 10 MeV, fast neutrons and atmospheric neutrinos have dominant contribution on the number of DC events (Abe et al. 2022b). Typically, the DC candidate rate is ∼1 day−1 in the reactor-on phase and 0.1 day−1 in the reactor-off phase. Usually, we call a KamLAND data set a “run,” which consists of typically 24 hr data. The number of expected DC events is estimated in run by run and the number of accidental clusters is calculated from that. Taking into account that time differences between each run are more than 10 s, there should be no accidental clusters that occur across two runs. As a result, the accumulated number of accidental clusters is \n\n\n\nnclusteraccidental=0.32−0.04+0.02\n\n clusters, and this rate is 0.023 cluster yr−1 on average. The error of \n\n\n\nnclusteraccidental\n\n includes systematic uncertainties of the number of expected DC events by reactor -\n\n\n\nν¯e\n\n, atmospheric neutrino, and fast neutron.","Citation Text":["Gando et al. 2013"],"Citation Start End":[[942,959]]} {"Identifier":"2022ApJ...934...85AAbe_et_al._2008_Instance_1","Paragraph":"To detect supernova neutrinos with the KamLAND data, a cluster of DC events is required: two DC events within a 10 s window. The very low DC rate enables us to use the minimum cluster condition (two DC events). An accidental DC event cluster is a background for supernova neutrinos. Based on the DC event studies, we evaluate the number of accidental cluster events (\n\n\n\n≡nclusteraccidental\n\n) via Monte-Carlo (MC) simulation. Accidental cluster rates and accumulation of \n\n\n\nnclusteraccidental\n\n are shown in Figure 1. Before distillation campaigns, the DC event is mainly caused by reactor -\n\n\n\nν¯e\n\n, and 13C(α, n)16O interaction has a secondary contribution (Abe et al. 2008). After distillation campaigns, the DC event by 13C(α, n)16O interaction decreases but reactor -\n\n\n\nν¯e\n\n is still a dominant component (Gando et al. 2011). Japanese reactors were shut down after the Great East Japan Earthquake in 2011. In the reactor-off phase (Gando et al. 2013), the rate of reactor -\n\n\n\nν¯e\n\n events is decreased. These trends of DC event rate are also shown in Figure 1. In an energy region above 10 MeV, fast neutrons and atmospheric neutrinos have dominant contribution on the number of DC events (Abe et al. 2022b). Typically, the DC candidate rate is ∼1 day−1 in the reactor-on phase and 0.1 day−1 in the reactor-off phase. Usually, we call a KamLAND data set a “run,” which consists of typically 24 hr data. The number of expected DC events is estimated in run by run and the number of accidental clusters is calculated from that. Taking into account that time differences between each run are more than 10 s, there should be no accidental clusters that occur across two runs. As a result, the accumulated number of accidental clusters is \n\n\n\nnclusteraccidental=0.32−0.04+0.02\n\n clusters, and this rate is 0.023 cluster yr−1 on average. The error of \n\n\n\nnclusteraccidental\n\n includes systematic uncertainties of the number of expected DC events by reactor -\n\n\n\nν¯e\n\n, atmospheric neutrino, and fast neutron.","Citation Text":["Abe et al. 2008"],"Citation Start End":[[663,678]]} {"Identifier":"2022ApJ...934...85AGando_et_al._2011_Instance_1","Paragraph":"To detect supernova neutrinos with the KamLAND data, a cluster of DC events is required: two DC events within a 10 s window. The very low DC rate enables us to use the minimum cluster condition (two DC events). An accidental DC event cluster is a background for supernova neutrinos. Based on the DC event studies, we evaluate the number of accidental cluster events (\n\n\n\n≡nclusteraccidental\n\n) via Monte-Carlo (MC) simulation. Accidental cluster rates and accumulation of \n\n\n\nnclusteraccidental\n\n are shown in Figure 1. Before distillation campaigns, the DC event is mainly caused by reactor -\n\n\n\nν¯e\n\n, and 13C(α, n)16O interaction has a secondary contribution (Abe et al. 2008). After distillation campaigns, the DC event by 13C(α, n)16O interaction decreases but reactor -\n\n\n\nν¯e\n\n is still a dominant component (Gando et al. 2011). Japanese reactors were shut down after the Great East Japan Earthquake in 2011. In the reactor-off phase (Gando et al. 2013), the rate of reactor -\n\n\n\nν¯e\n\n events is decreased. These trends of DC event rate are also shown in Figure 1. In an energy region above 10 MeV, fast neutrons and atmospheric neutrinos have dominant contribution on the number of DC events (Abe et al. 2022b). Typically, the DC candidate rate is ∼1 day−1 in the reactor-on phase and 0.1 day−1 in the reactor-off phase. Usually, we call a KamLAND data set a “run,” which consists of typically 24 hr data. The number of expected DC events is estimated in run by run and the number of accidental clusters is calculated from that. Taking into account that time differences between each run are more than 10 s, there should be no accidental clusters that occur across two runs. As a result, the accumulated number of accidental clusters is \n\n\n\nnclusteraccidental=0.32−0.04+0.02\n\n clusters, and this rate is 0.023 cluster yr−1 on average. The error of \n\n\n\nnclusteraccidental\n\n includes systematic uncertainties of the number of expected DC events by reactor -\n\n\n\nν¯e\n\n, atmospheric neutrino, and fast neutron.","Citation Text":["Gando et al. 2011"],"Citation Start End":[[816,833]]} {"Identifier":"2019ApJ...876...12A__Azadi_et_al._2017_Instance_1","Paragraph":"One factor that we have not taken into account so far is that the strength of an AGN may affect how strong the corresponding emission from the NLR is. Thus, it may be the case that lower-luminosity or lower-accretion-rate AGNs are more easily overwhelmed by star formation. Therefore, we next explore whether correctly and incorrectly classified X-ray AGNs differ in their intrinsic AGN properties. One of the indicators of the accretion strength of an AGN in the optical regime is the luminosity of the forbidden [O iii] line, \n\n\n\n\n\n, which scales with the bolometric luminosity of the AGN (Mulchaey et al. 1994; Heckman et al. 2005; LaMassa et al. 2010; Azadi et al. 2017; Glikman et al. 2018). A related quantity, \n\n\n\n\n\n divided by the fourth power of the stellar velocity dispersion, σ4, can provide an estimate of the Eddington ratio of the AGN (Kewley et al. 2006). Trump et al. (2015) suggested that higher sSFR galaxies must have more efficient AGNs in order to be classified as BPT–AGNs because of the relative contributions from star formation. We show \n\n\n\n\n\n and \n\n\n\n\n\n versus stellar mass in Figures 8 and 9, respectively, with the BPT star-forming galaxies from GSWLC-M1 composing the backgrounds in Figures 8(a) and 9(a) and the BPT–AGNs from GSWLC-M1 making up the backgrounds in Figures 8(b) and 9(b). In Figures 8 and 9, there appear to be two distinct sequences for the two BPT types when mass is included, where in Figure 8(a), the background BPT star-forming galaxies form one sequence where \n\n\n\n\n\n appears to correlate with stellar mass, including galaxies with masses up to \n\n\n\n\n\n, while the star-forming galaxies in Figure 9(a) do not show a strong dependence of proxy Eddington ratio with stellar mass, which is expected because \n\n\n\n\n\n from star-forming galaxies primarily comes from star formation. The BPT–AGNs form sequences in Figures 8(b) and 9(b) that have no apparent dependence on mass with masses ranging roughly from \n\n\n\n\n\n. The existence of these two sequences is apparently the case because of the different sources of [O iii] emission that are dominant in BPT star-forming galaxies versus BPT–AGNs. The majority of the BPT–H ii are more consistent with the background star-forming galaxies in Figures 8(a) and 9(a), whereas the BPT–AGNs all appear consistent with the background BPT–AGNs shown in Figures 8(b) and 9(b), which is to be expected if the NLR dominates [O iii] emission. Six BPT–H ii are more consistent with the background BPT–AGNs in Figures 8(b) and 9(b), and if the NLR is indeed the source of their [O iii] emission, their Eddington ratios are much lower than the average BPT–AGNs, suggesting that they have relatively inefficient accretion. We will return to these outliers in Section 3.2.3.","Citation Text":["Azadi et al. 2017"],"Citation Start End":[[656,673]]} {"Identifier":"2022ApJ...937....5S__Margalit_&_Metzger_2016_Instance_1","Paragraph":"The disk-wind outflows that accompany highly super-Eddington accretion carry a total mass-loss rate \n\n\n\nṀw\n\n, which nearly equals the entire mass-transfer rate, i.e., \n\n\n\nṀw∼Ṁ\n\n (e.g., Blandford & Begelman 1999; Hashizume et al. 2015), with only a small fraction making its way down to the BH\/NS surface. Depending on the radial scale of their launching point in the disk or binary, the outflows can possess a range of speeds, from values similar to the binary orbital velocity, v\norb ≲ 100 km s−1, to the transrelativistic speeds v\nj ≳ 0.3c that characterize jet-like outflows from the innermost radii of the disk (and similar to those observed in SS 433 and ULX; e.g., Jeffrey et al. 2016 and references therein). In ADIOS models for the radial disk structure (Blandford & Begelman 1999; Margalit & Metzger 2016), the mass accretion rate decreases as a power law with radius \n\n\n\nṀ∝rp\n\n for \n\n\n\nr∈[rin,rout≲Rtr]\n\n, where r\nout ≫ r\nin. Assuming the outflows local to each annulus in the disk reach an asymptotic velocity equal to the local disk escape velocity, the kinetic energy-averaged wind velocity is given by (e.g., Metzger 2012)\n6\n\n\n\nvw≈p1−pGM•rinrinroutp≈0.05cM•10M⊙0.3rin6rg−0.2routR⊙−0.3,\n\nwhere in the second equality we have normalized r\nin to gravitational radius r\ng = GM\n•\/c\n2 and take p = 0.6 (as supported by hydrodynamical simulations of radiatively inefficient accretion flows; e.g., Yuan & Narayan 2014; Hu et al. 2022). In what follows, we take v\nw ∼ 0.03c as a fiducial value, consistent with that expected for a main-sequence or moderately evolved donor star feeding a relatively compact accretion flow, r\nout ∼ R\n⊙. However, lower value v\nw ≲ 0.01 c may be appropriate for a giant donor star (r\nout ≳ 102\nR\n⊙) or for larger values of p. The kinetic luminosity of the wind is then\n7\n\n\n\nLw≈12Ṁwvw2≈1042ergs−1Ṁw105ṀEdd×M•10M⊙vw,92ergs−1,\n\nwhere v\nw,9 = v\nw\/(109 cm s−1) and hereafter we adopt the short-hand notation Y\nx ≡ Y\/10x for quantities given in cgs units. In analytic estimates hereafter, we shall typically fix the value of M\n• = 10M\n⊙ and use L\nw and \n\n\n\nṀw\n\n interchangeably.","Citation Text":["Margalit & Metzger 2016"],"Citation Start End":[[793,816]]} {"Identifier":"2020ApJ...893..124Z__Wang_et_al._2019_Instance_1","Paragraph":"In hydrodynamic and magnetohydrodynamic systems, different fluctuations interact with each other nonlinearly, generating turbulence (Matthaeus et al. 2015). One of the most important characteristics of turbulence is the existence of intermittency among various scales. Spatial intermittency manifests as coherent structures with large gradient at small scales. In ordinary fluids, coherent structures include a tangle of vortex filaments where vorticity is highly concentrated (Frisch 1995). In the turbulent plasma environments, examples of intermittent structures include current sheets, discontinuities, shock waves, and Alfvénic vortices (Veltri & Mangeney 1999; Sundkvist et al. 2007; Lion et al. 2016; Wang et al. 2019). The intermittency will influence the measured statistical properties of the fluctuating quantities. For example, the growth of flatness with decreasing scales indicates the existence of intermittency. Plenty of simulation works (Servidio et al. 2011; Karimabadi et al. 2013; Tenbarge & Howes 2013; Wan et al. 2015, 2016; Zhang et al. 2015) have indicated that dissipation, acceleration, and thermalization of turbulent plasmas mainly take place near intermittent structures on kinetic scale, while the actual physical mechanisms behind dissipation remain unclear. There are a variety of diagnostic approaches to measure intermittency. (1) Probability density functions (PDFs) of scale-dependent field increments develop heavy tails because of intermittency, and the tail is more enhanced with increasing intermittency (Marsch & Tu 1994). (2) The scale dependency of the normalized fourth-order moment, known as flatness, \n\n\n\n\n\n, where δv = v(t + τ)−v(t), is an alternative representation. This quantity increases as the intermittency becomes more significant along with decreasing scales. (3) The p-th order structure function, \n\n\n\n\n\n, will be larger than that for Gaussian PDF without intermittency and the scaling exponent, ζ(p), has a nonlinear form when intermittency presents. Based on such diagnostic approaches, the properties of intermittency in plasmas have been widely investigated in the solar atmosphere, magnetosheath, solar wind, termination shock, etc. (Burlaga 1991a, 1991b; Marsch & Liu 1993; Horbury et al. 1995; Macek et al. 2011, 2017; Chasapis et al. 2018). These observational analyses have revealed that intermittency is widely existing in the heliosphere and immensely influencing plasma dynamics.","Citation Text":["Wang et al. 2019"],"Citation Start End":[[708,724]]} {"Identifier":"2020ApJ...893..124ZFrisch_1995_Instance_1","Paragraph":"In hydrodynamic and magnetohydrodynamic systems, different fluctuations interact with each other nonlinearly, generating turbulence (Matthaeus et al. 2015). One of the most important characteristics of turbulence is the existence of intermittency among various scales. Spatial intermittency manifests as coherent structures with large gradient at small scales. In ordinary fluids, coherent structures include a tangle of vortex filaments where vorticity is highly concentrated (Frisch 1995). In the turbulent plasma environments, examples of intermittent structures include current sheets, discontinuities, shock waves, and Alfvénic vortices (Veltri & Mangeney 1999; Sundkvist et al. 2007; Lion et al. 2016; Wang et al. 2019). The intermittency will influence the measured statistical properties of the fluctuating quantities. For example, the growth of flatness with decreasing scales indicates the existence of intermittency. Plenty of simulation works (Servidio et al. 2011; Karimabadi et al. 2013; Tenbarge & Howes 2013; Wan et al. 2015, 2016; Zhang et al. 2015) have indicated that dissipation, acceleration, and thermalization of turbulent plasmas mainly take place near intermittent structures on kinetic scale, while the actual physical mechanisms behind dissipation remain unclear. There are a variety of diagnostic approaches to measure intermittency. (1) Probability density functions (PDFs) of scale-dependent field increments develop heavy tails because of intermittency, and the tail is more enhanced with increasing intermittency (Marsch & Tu 1994). (2) The scale dependency of the normalized fourth-order moment, known as flatness, \n\n\n\n\n\n, where δv = v(t + τ)−v(t), is an alternative representation. This quantity increases as the intermittency becomes more significant along with decreasing scales. (3) The p-th order structure function, \n\n\n\n\n\n, will be larger than that for Gaussian PDF without intermittency and the scaling exponent, ζ(p), has a nonlinear form when intermittency presents. Based on such diagnostic approaches, the properties of intermittency in plasmas have been widely investigated in the solar atmosphere, magnetosheath, solar wind, termination shock, etc. (Burlaga 1991a, 1991b; Marsch & Liu 1993; Horbury et al. 1995; Macek et al. 2011, 2017; Chasapis et al. 2018). These observational analyses have revealed that intermittency is widely existing in the heliosphere and immensely influencing plasma dynamics.","Citation Text":["Frisch 1995"],"Citation Start End":[[478,489]]} {"Identifier":"2020ApJ...893..124ZMatthaeus_et_al._2015_Instance_1","Paragraph":"In hydrodynamic and magnetohydrodynamic systems, different fluctuations interact with each other nonlinearly, generating turbulence (Matthaeus et al. 2015). One of the most important characteristics of turbulence is the existence of intermittency among various scales. Spatial intermittency manifests as coherent structures with large gradient at small scales. In ordinary fluids, coherent structures include a tangle of vortex filaments where vorticity is highly concentrated (Frisch 1995). In the turbulent plasma environments, examples of intermittent structures include current sheets, discontinuities, shock waves, and Alfvénic vortices (Veltri & Mangeney 1999; Sundkvist et al. 2007; Lion et al. 2016; Wang et al. 2019). The intermittency will influence the measured statistical properties of the fluctuating quantities. For example, the growth of flatness with decreasing scales indicates the existence of intermittency. Plenty of simulation works (Servidio et al. 2011; Karimabadi et al. 2013; Tenbarge & Howes 2013; Wan et al. 2015, 2016; Zhang et al. 2015) have indicated that dissipation, acceleration, and thermalization of turbulent plasmas mainly take place near intermittent structures on kinetic scale, while the actual physical mechanisms behind dissipation remain unclear. There are a variety of diagnostic approaches to measure intermittency. (1) Probability density functions (PDFs) of scale-dependent field increments develop heavy tails because of intermittency, and the tail is more enhanced with increasing intermittency (Marsch & Tu 1994). (2) The scale dependency of the normalized fourth-order moment, known as flatness, \n\n\n\n\n\n, where δv = v(t + τ)−v(t), is an alternative representation. This quantity increases as the intermittency becomes more significant along with decreasing scales. (3) The p-th order structure function, \n\n\n\n\n\n, will be larger than that for Gaussian PDF without intermittency and the scaling exponent, ζ(p), has a nonlinear form when intermittency presents. Based on such diagnostic approaches, the properties of intermittency in plasmas have been widely investigated in the solar atmosphere, magnetosheath, solar wind, termination shock, etc. (Burlaga 1991a, 1991b; Marsch & Liu 1993; Horbury et al. 1995; Macek et al. 2011, 2017; Chasapis et al. 2018). These observational analyses have revealed that intermittency is widely existing in the heliosphere and immensely influencing plasma dynamics.","Citation Text":["Matthaeus et al. 2015"],"Citation Start End":[[133,154]]} {"Identifier":"2020ApJ...893..124ZServidio_et_al._2011_Instance_1","Paragraph":"In hydrodynamic and magnetohydrodynamic systems, different fluctuations interact with each other nonlinearly, generating turbulence (Matthaeus et al. 2015). One of the most important characteristics of turbulence is the existence of intermittency among various scales. Spatial intermittency manifests as coherent structures with large gradient at small scales. In ordinary fluids, coherent structures include a tangle of vortex filaments where vorticity is highly concentrated (Frisch 1995). In the turbulent plasma environments, examples of intermittent structures include current sheets, discontinuities, shock waves, and Alfvénic vortices (Veltri & Mangeney 1999; Sundkvist et al. 2007; Lion et al. 2016; Wang et al. 2019). The intermittency will influence the measured statistical properties of the fluctuating quantities. For example, the growth of flatness with decreasing scales indicates the existence of intermittency. Plenty of simulation works (Servidio et al. 2011; Karimabadi et al. 2013; Tenbarge & Howes 2013; Wan et al. 2015, 2016; Zhang et al. 2015) have indicated that dissipation, acceleration, and thermalization of turbulent plasmas mainly take place near intermittent structures on kinetic scale, while the actual physical mechanisms behind dissipation remain unclear. There are a variety of diagnostic approaches to measure intermittency. (1) Probability density functions (PDFs) of scale-dependent field increments develop heavy tails because of intermittency, and the tail is more enhanced with increasing intermittency (Marsch & Tu 1994). (2) The scale dependency of the normalized fourth-order moment, known as flatness, \n\n\n\n\n\n, where δv = v(t + τ)−v(t), is an alternative representation. This quantity increases as the intermittency becomes more significant along with decreasing scales. (3) The p-th order structure function, \n\n\n\n\n\n, will be larger than that for Gaussian PDF without intermittency and the scaling exponent, ζ(p), has a nonlinear form when intermittency presents. Based on such diagnostic approaches, the properties of intermittency in plasmas have been widely investigated in the solar atmosphere, magnetosheath, solar wind, termination shock, etc. (Burlaga 1991a, 1991b; Marsch & Liu 1993; Horbury et al. 1995; Macek et al. 2011, 2017; Chasapis et al. 2018). These observational analyses have revealed that intermittency is widely existing in the heliosphere and immensely influencing plasma dynamics.","Citation Text":["Servidio et al. 2011"],"Citation Start End":[[956,976]]} {"Identifier":"2020ApJ...893..124ZMarsch_&_Tu_1994_Instance_1","Paragraph":"In hydrodynamic and magnetohydrodynamic systems, different fluctuations interact with each other nonlinearly, generating turbulence (Matthaeus et al. 2015). One of the most important characteristics of turbulence is the existence of intermittency among various scales. Spatial intermittency manifests as coherent structures with large gradient at small scales. In ordinary fluids, coherent structures include a tangle of vortex filaments where vorticity is highly concentrated (Frisch 1995). In the turbulent plasma environments, examples of intermittent structures include current sheets, discontinuities, shock waves, and Alfvénic vortices (Veltri & Mangeney 1999; Sundkvist et al. 2007; Lion et al. 2016; Wang et al. 2019). The intermittency will influence the measured statistical properties of the fluctuating quantities. For example, the growth of flatness with decreasing scales indicates the existence of intermittency. Plenty of simulation works (Servidio et al. 2011; Karimabadi et al. 2013; Tenbarge & Howes 2013; Wan et al. 2015, 2016; Zhang et al. 2015) have indicated that dissipation, acceleration, and thermalization of turbulent plasmas mainly take place near intermittent structures on kinetic scale, while the actual physical mechanisms behind dissipation remain unclear. There are a variety of diagnostic approaches to measure intermittency. (1) Probability density functions (PDFs) of scale-dependent field increments develop heavy tails because of intermittency, and the tail is more enhanced with increasing intermittency (Marsch & Tu 1994). (2) The scale dependency of the normalized fourth-order moment, known as flatness, \n\n\n\n\n\n, where δv = v(t + τ)−v(t), is an alternative representation. This quantity increases as the intermittency becomes more significant along with decreasing scales. (3) The p-th order structure function, \n\n\n\n\n\n, will be larger than that for Gaussian PDF without intermittency and the scaling exponent, ζ(p), has a nonlinear form when intermittency presents. Based on such diagnostic approaches, the properties of intermittency in plasmas have been widely investigated in the solar atmosphere, magnetosheath, solar wind, termination shock, etc. (Burlaga 1991a, 1991b; Marsch & Liu 1993; Horbury et al. 1995; Macek et al. 2011, 2017; Chasapis et al. 2018). These observational analyses have revealed that intermittency is widely existing in the heliosphere and immensely influencing plasma dynamics.","Citation Text":["Marsch & Tu 1994"],"Citation Start End":[[1546,1562]]} {"Identifier":"2020ApJ...893..124ZHorbury_et_al._1995_Instance_1","Paragraph":"In hydrodynamic and magnetohydrodynamic systems, different fluctuations interact with each other nonlinearly, generating turbulence (Matthaeus et al. 2015). One of the most important characteristics of turbulence is the existence of intermittency among various scales. Spatial intermittency manifests as coherent structures with large gradient at small scales. In ordinary fluids, coherent structures include a tangle of vortex filaments where vorticity is highly concentrated (Frisch 1995). In the turbulent plasma environments, examples of intermittent structures include current sheets, discontinuities, shock waves, and Alfvénic vortices (Veltri & Mangeney 1999; Sundkvist et al. 2007; Lion et al. 2016; Wang et al. 2019). The intermittency will influence the measured statistical properties of the fluctuating quantities. For example, the growth of flatness with decreasing scales indicates the existence of intermittency. Plenty of simulation works (Servidio et al. 2011; Karimabadi et al. 2013; Tenbarge & Howes 2013; Wan et al. 2015, 2016; Zhang et al. 2015) have indicated that dissipation, acceleration, and thermalization of turbulent plasmas mainly take place near intermittent structures on kinetic scale, while the actual physical mechanisms behind dissipation remain unclear. There are a variety of diagnostic approaches to measure intermittency. (1) Probability density functions (PDFs) of scale-dependent field increments develop heavy tails because of intermittency, and the tail is more enhanced with increasing intermittency (Marsch & Tu 1994). (2) The scale dependency of the normalized fourth-order moment, known as flatness, \n\n\n\n\n\n, where δv = v(t + τ)−v(t), is an alternative representation. This quantity increases as the intermittency becomes more significant along with decreasing scales. (3) The p-th order structure function, \n\n\n\n\n\n, will be larger than that for Gaussian PDF without intermittency and the scaling exponent, ζ(p), has a nonlinear form when intermittency presents. Based on such diagnostic approaches, the properties of intermittency in plasmas have been widely investigated in the solar atmosphere, magnetosheath, solar wind, termination shock, etc. (Burlaga 1991a, 1991b; Marsch & Liu 1993; Horbury et al. 1995; Macek et al. 2011, 2017; Chasapis et al. 2018). These observational analyses have revealed that intermittency is widely existing in the heliosphere and immensely influencing plasma dynamics.","Citation Text":["Horbury et al. 1995"],"Citation Start End":[[2237,2256]]} {"Identifier":"2018ApJ...852L..20A__Bonifacio_et_al._2015_Instance_1","Paragraph":"J0815+4729 is a main-sequence star (T\n\n\n\n\n\n\n\neff\n\n\n=\n6215\n±\n82\n\n\n K, \n\n\n\n\nlog\ng\n\n\n = 4.7±0.5) with a metallicity of [Fe\/H] ≤ −5.8 dex. Finding unevolved stars at this extremely low metallicity is very important since their stellar surface composition is not expected to be significantly modified by any internal mixing processes as in giant stars (Spite et al. 2005). J0815+4729 is similar to HE 1327–2326 in regard to its carbon enhancement, effective temperature, and metallicity. HE 1327–2326 is considered a turn-off\/subgiant star, while J0815+4729 appears to be a dwarf. The ISIS spectrum of HE 1327–2326 indicates a metallicity of [Fe\/H] ∼ −4.9 since the stellar Ca line is blended in that spectrum with the ISM features (Aguado et al. 2017b). However, the authors proposed a simple analysis taking into account the ISM absorption based on the UVES spectrum of HE 1327–2326. For J0815+4729, we require a high-resolution spectrum to clearly isolate the stellar Ca feature from possible additional ISM lines, and thus together with the detection of Fe lines, to establish the metallicity of this star. There are two other confirmed dwarf stars in this metallicity regime: one without any detectable carbon, J1029+1729 (Caffau et al. 2011), and another carbon-enhanced unevolved star, J1035+0641 (Bonifacio et al. 2015). The majority of extremely metal-poor stars shows overabundances of carbon, [C\/Fe] > 0.7, and it appears that carbon-enhanced metal-poor (CEMP) stars split into two groups, with dramatically different carbon abundances (see, e.g., Beers & Christlieb 2005; Allende Prieto et al. 2015; Bonifacio et al. 2015 and references therein). The two carbon bands (high and low) studied have different origins. On the one hand, CEMP stars in the high-carbon band (A(C) ∼ 8.2) are probably produced by mass transfer from a binary companion, most likely an AGB star (Starkenburg et al. 2014). On the other hand, objects lying in the low-carbon band (A(C) ∼ 6.8) are thought to show the original carbon abundance inherited by the star from the ISM (Stancliffe 2009; Bonifacio et al. 2015; Abate et al. 2016). J0815+4729 has an abundance ratio of \n\n\n\n\n\n\n[\n\nC\n\n\/\n\nFe\n\n]\n\n\n≥\n+\n5.0\n\n\n dex corresponding to A(C) ∼ 7.7 dex (adopting [Fe\/H] ≤ −5.8). In Figure 4 (bottom panel), we show the carbon abundance ratio [C\/Fe] for all stars at [Fe\/H] −4.5. All stars in this metallicity regime are considered to belong to the low-carbon band (Bonifacio et al. 2015), except for J0815+4729, which appears to be in between the low- and high-carbon bands. Both metallicity and carbon abundance are considered upper and lower limits, respectively. High-resolution spectra would be very useful to measure other elemental abundances and investigate the properties of the first supernovae. In particular, the barium abundance, or that of any other s-element, is not measurable from ISIS or OSIRIS spectra, and this is required to determine whether J0815+4729 is a CEMP-s, CEMP-r, or i-process star (Hampel et al. 2016). If we establish the abundance pattern, we will learn about the progenitor properties. Finally, the radial velocity accuracy from medium-resolution data is not enough to discard variations among different exposures, which would be indicative of binarity.","Citation Text":["Bonifacio et al. 2015"],"Citation Start End":[[1300,1321]]} {"Identifier":"2018ApJ...852L..20A__Bonifacio_et_al._2015_Instance_2","Paragraph":"J0815+4729 is a main-sequence star (T\n\n\n\n\n\n\n\neff\n\n\n=\n6215\n±\n82\n\n\n K, \n\n\n\n\nlog\ng\n\n\n = 4.7±0.5) with a metallicity of [Fe\/H] ≤ −5.8 dex. Finding unevolved stars at this extremely low metallicity is very important since their stellar surface composition is not expected to be significantly modified by any internal mixing processes as in giant stars (Spite et al. 2005). J0815+4729 is similar to HE 1327–2326 in regard to its carbon enhancement, effective temperature, and metallicity. HE 1327–2326 is considered a turn-off\/subgiant star, while J0815+4729 appears to be a dwarf. The ISIS spectrum of HE 1327–2326 indicates a metallicity of [Fe\/H] ∼ −4.9 since the stellar Ca line is blended in that spectrum with the ISM features (Aguado et al. 2017b). However, the authors proposed a simple analysis taking into account the ISM absorption based on the UVES spectrum of HE 1327–2326. For J0815+4729, we require a high-resolution spectrum to clearly isolate the stellar Ca feature from possible additional ISM lines, and thus together with the detection of Fe lines, to establish the metallicity of this star. There are two other confirmed dwarf stars in this metallicity regime: one without any detectable carbon, J1029+1729 (Caffau et al. 2011), and another carbon-enhanced unevolved star, J1035+0641 (Bonifacio et al. 2015). The majority of extremely metal-poor stars shows overabundances of carbon, [C\/Fe] > 0.7, and it appears that carbon-enhanced metal-poor (CEMP) stars split into two groups, with dramatically different carbon abundances (see, e.g., Beers & Christlieb 2005; Allende Prieto et al. 2015; Bonifacio et al. 2015 and references therein). The two carbon bands (high and low) studied have different origins. On the one hand, CEMP stars in the high-carbon band (A(C) ∼ 8.2) are probably produced by mass transfer from a binary companion, most likely an AGB star (Starkenburg et al. 2014). On the other hand, objects lying in the low-carbon band (A(C) ∼ 6.8) are thought to show the original carbon abundance inherited by the star from the ISM (Stancliffe 2009; Bonifacio et al. 2015; Abate et al. 2016). J0815+4729 has an abundance ratio of \n\n\n\n\n\n\n[\n\nC\n\n\/\n\nFe\n\n]\n\n\n≥\n+\n5.0\n\n\n dex corresponding to A(C) ∼ 7.7 dex (adopting [Fe\/H] ≤ −5.8). In Figure 4 (bottom panel), we show the carbon abundance ratio [C\/Fe] for all stars at [Fe\/H] −4.5. All stars in this metallicity regime are considered to belong to the low-carbon band (Bonifacio et al. 2015), except for J0815+4729, which appears to be in between the low- and high-carbon bands. Both metallicity and carbon abundance are considered upper and lower limits, respectively. High-resolution spectra would be very useful to measure other elemental abundances and investigate the properties of the first supernovae. In particular, the barium abundance, or that of any other s-element, is not measurable from ISIS or OSIRIS spectra, and this is required to determine whether J0815+4729 is a CEMP-s, CEMP-r, or i-process star (Hampel et al. 2016). If we establish the abundance pattern, we will learn about the progenitor properties. Finally, the radial velocity accuracy from medium-resolution data is not enough to discard variations among different exposures, which would be indicative of binarity.","Citation Text":["Bonifacio et al. 2015"],"Citation Start End":[[1607,1628]]} {"Identifier":"2018ApJ...852L..20A__Bonifacio_et_al._2015_Instance_3","Paragraph":"J0815+4729 is a main-sequence star (T\n\n\n\n\n\n\n\neff\n\n\n=\n6215\n±\n82\n\n\n K, \n\n\n\n\nlog\ng\n\n\n = 4.7±0.5) with a metallicity of [Fe\/H] ≤ −5.8 dex. Finding unevolved stars at this extremely low metallicity is very important since their stellar surface composition is not expected to be significantly modified by any internal mixing processes as in giant stars (Spite et al. 2005). J0815+4729 is similar to HE 1327–2326 in regard to its carbon enhancement, effective temperature, and metallicity. HE 1327–2326 is considered a turn-off\/subgiant star, while J0815+4729 appears to be a dwarf. The ISIS spectrum of HE 1327–2326 indicates a metallicity of [Fe\/H] ∼ −4.9 since the stellar Ca line is blended in that spectrum with the ISM features (Aguado et al. 2017b). However, the authors proposed a simple analysis taking into account the ISM absorption based on the UVES spectrum of HE 1327–2326. For J0815+4729, we require a high-resolution spectrum to clearly isolate the stellar Ca feature from possible additional ISM lines, and thus together with the detection of Fe lines, to establish the metallicity of this star. There are two other confirmed dwarf stars in this metallicity regime: one without any detectable carbon, J1029+1729 (Caffau et al. 2011), and another carbon-enhanced unevolved star, J1035+0641 (Bonifacio et al. 2015). The majority of extremely metal-poor stars shows overabundances of carbon, [C\/Fe] > 0.7, and it appears that carbon-enhanced metal-poor (CEMP) stars split into two groups, with dramatically different carbon abundances (see, e.g., Beers & Christlieb 2005; Allende Prieto et al. 2015; Bonifacio et al. 2015 and references therein). The two carbon bands (high and low) studied have different origins. On the one hand, CEMP stars in the high-carbon band (A(C) ∼ 8.2) are probably produced by mass transfer from a binary companion, most likely an AGB star (Starkenburg et al. 2014). On the other hand, objects lying in the low-carbon band (A(C) ∼ 6.8) are thought to show the original carbon abundance inherited by the star from the ISM (Stancliffe 2009; Bonifacio et al. 2015; Abate et al. 2016). J0815+4729 has an abundance ratio of \n\n\n\n\n\n\n[\n\nC\n\n\/\n\nFe\n\n]\n\n\n≥\n+\n5.0\n\n\n dex corresponding to A(C) ∼ 7.7 dex (adopting [Fe\/H] ≤ −5.8). In Figure 4 (bottom panel), we show the carbon abundance ratio [C\/Fe] for all stars at [Fe\/H] −4.5. All stars in this metallicity regime are considered to belong to the low-carbon band (Bonifacio et al. 2015), except for J0815+4729, which appears to be in between the low- and high-carbon bands. Both metallicity and carbon abundance are considered upper and lower limits, respectively. High-resolution spectra would be very useful to measure other elemental abundances and investigate the properties of the first supernovae. In particular, the barium abundance, or that of any other s-element, is not measurable from ISIS or OSIRIS spectra, and this is required to determine whether J0815+4729 is a CEMP-s, CEMP-r, or i-process star (Hampel et al. 2016). If we establish the abundance pattern, we will learn about the progenitor properties. Finally, the radial velocity accuracy from medium-resolution data is not enough to discard variations among different exposures, which would be indicative of binarity.","Citation Text":["Bonifacio et al. 2015"],"Citation Start End":[[2074,2095]]} {"Identifier":"2018ApJ...852L..20A__Bonifacio_et_al._2015_Instance_4","Paragraph":"J0815+4729 is a main-sequence star (T\n\n\n\n\n\n\n\neff\n\n\n=\n6215\n±\n82\n\n\n K, \n\n\n\n\nlog\ng\n\n\n = 4.7±0.5) with a metallicity of [Fe\/H] ≤ −5.8 dex. Finding unevolved stars at this extremely low metallicity is very important since their stellar surface composition is not expected to be significantly modified by any internal mixing processes as in giant stars (Spite et al. 2005). J0815+4729 is similar to HE 1327–2326 in regard to its carbon enhancement, effective temperature, and metallicity. HE 1327–2326 is considered a turn-off\/subgiant star, while J0815+4729 appears to be a dwarf. The ISIS spectrum of HE 1327–2326 indicates a metallicity of [Fe\/H] ∼ −4.9 since the stellar Ca line is blended in that spectrum with the ISM features (Aguado et al. 2017b). However, the authors proposed a simple analysis taking into account the ISM absorption based on the UVES spectrum of HE 1327–2326. For J0815+4729, we require a high-resolution spectrum to clearly isolate the stellar Ca feature from possible additional ISM lines, and thus together with the detection of Fe lines, to establish the metallicity of this star. There are two other confirmed dwarf stars in this metallicity regime: one without any detectable carbon, J1029+1729 (Caffau et al. 2011), and another carbon-enhanced unevolved star, J1035+0641 (Bonifacio et al. 2015). The majority of extremely metal-poor stars shows overabundances of carbon, [C\/Fe] > 0.7, and it appears that carbon-enhanced metal-poor (CEMP) stars split into two groups, with dramatically different carbon abundances (see, e.g., Beers & Christlieb 2005; Allende Prieto et al. 2015; Bonifacio et al. 2015 and references therein). The two carbon bands (high and low) studied have different origins. On the one hand, CEMP stars in the high-carbon band (A(C) ∼ 8.2) are probably produced by mass transfer from a binary companion, most likely an AGB star (Starkenburg et al. 2014). On the other hand, objects lying in the low-carbon band (A(C) ∼ 6.8) are thought to show the original carbon abundance inherited by the star from the ISM (Stancliffe 2009; Bonifacio et al. 2015; Abate et al. 2016). J0815+4729 has an abundance ratio of \n\n\n\n\n\n\n[\n\nC\n\n\/\n\nFe\n\n]\n\n\n≥\n+\n5.0\n\n\n dex corresponding to A(C) ∼ 7.7 dex (adopting [Fe\/H] ≤ −5.8). In Figure 4 (bottom panel), we show the carbon abundance ratio [C\/Fe] for all stars at [Fe\/H] −4.5. All stars in this metallicity regime are considered to belong to the low-carbon band (Bonifacio et al. 2015), except for J0815+4729, which appears to be in between the low- and high-carbon bands. Both metallicity and carbon abundance are considered upper and lower limits, respectively. High-resolution spectra would be very useful to measure other elemental abundances and investigate the properties of the first supernovae. In particular, the barium abundance, or that of any other s-element, is not measurable from ISIS or OSIRIS spectra, and this is required to determine whether J0815+4729 is a CEMP-s, CEMP-r, or i-process star (Hampel et al. 2016). If we establish the abundance pattern, we will learn about the progenitor properties. Finally, the radial velocity accuracy from medium-resolution data is not enough to discard variations among different exposures, which would be indicative of binarity.","Citation Text":["Bonifacio et al. 2015"],"Citation Start End":[[2439,2460]]} {"Identifier":"2019AandA...622A..96C__Perez_et_al._2015_Instance_1","Paragraph":"The distributions of separations at apoapsis and periapsis from our LSMC analysis shown in the left panel of Fig. 11 indicate a range at 68%∼18–57 au. If the companion is coplanar with the outer disk, a ∼0.25 M⊙ companion with a 50 au apoapsis and e ∼ 0.5 − 0.7 would in principle create a region of orbital instability extending out to ∼100 au (Holman & Wiegert 1999), which is the innermost possible location for the outer disk (e.g., Fukagawa et al. 2006; Casassus et al. 2012; Rameau et al. 2012; Rodigas et al. 2014; Avenhaus et al. 2017). Nevertheless, the inclination and longitude of node of HD 142527B disagree with those of the outer circumstellar disk (i = 28°, Ω = 160°, Verhoeff et al. 2011; Perez et al. 2015), as has been reported by Lacour et al. (2016). This result would at first sight rule out that HD 142527B is responsible for the outer disk truncation. However, recent hydrodynamical simulations have shown that for an eccentric companion with an almost polar inclination to the outer disk that approaches its periapsis passage, the interactions of companion and disk can reproduce several of the main observed disk features, such as its large cavity, and with the correct position angles, its spiral features and shadows (Price et al. 2018). This orbital configuration is broadly consistent with the results from our orbital analysis. On the other hand, the orbital plane of the companion is close to the plane of the inner circumstellar disk, as previously suggested by Lacour et al. (2016). The inner disk has a position angle of 110 ± 10° from CO(6-5) kinematics measured with ALMA (Casassus et al. 2015). Its mean radius is estimated to be about 10 au from near-infrared interferometric observations (Anthonioz et al., in prep.). From MIR imaging and SED modeling, Verhoeff et al. (2011) derived a maximum radial extension for the inner disk up to 30 au. However, Avenhaus et al. (2014) imaged the inner circumstellar environment down to ∼0.1″ (15 au) in polarized scattered light with NaCo, but did not detect traces of an inner disk. More recently, Avenhaus et al. (2017) imaged the disk in visible polarized light with SPHERE down to 25 mas (∼4 au) and found evidence for dust scattering close to the star, although it remains unclear if this scattering is related to the inner disk because of geometrical discrepancies with predictions from a modeling of the shadows projected onto the outer disk (Marino et al. 2015). Using our orbital analysis of the companion, we derived the distribution of its separation at periapsis (Fig. 11, right panel) and find a 68% confidence interval of ∼10 − 12 au. This results indicates that the shape of the inner disk is strongly affected by HD 142527B.","Citation Text":["Perez et al. 2015"],"Citation Start End":[[705,722]]} {"Identifier":"2019AandA...622A..9Holman_&_Wiegert_1999_Instance_1","Paragraph":"The distributions of separations at apoapsis and periapsis from our LSMC analysis shown in the left panel of Fig. 11 indicate a range at 68%∼18–57 au. If the companion is coplanar with the outer disk, a ∼0.25 M⊙ companion with a 50 au apoapsis and e ∼ 0.5 − 0.7 would in principle create a region of orbital instability extending out to ∼100 au (Holman & Wiegert 1999), which is the innermost possible location for the outer disk (e.g., Fukagawa et al. 2006; Casassus et al. 2012; Rameau et al. 2012; Rodigas et al. 2014; Avenhaus et al. 2017). Nevertheless, the inclination and longitude of node of HD 142527B disagree with those of the outer circumstellar disk (i = 28°, Ω = 160°, Verhoeff et al. 2011; Perez et al. 2015), as has been reported by Lacour et al. (2016). This result would at first sight rule out that HD 142527B is responsible for the outer disk truncation. However, recent hydrodynamical simulations have shown that for an eccentric companion with an almost polar inclination to the outer disk that approaches its periapsis passage, the interactions of companion and disk can reproduce several of the main observed disk features, such as its large cavity, and with the correct position angles, its spiral features and shadows (Price et al. 2018). This orbital configuration is broadly consistent with the results from our orbital analysis. On the other hand, the orbital plane of the companion is close to the plane of the inner circumstellar disk, as previously suggested by Lacour et al. (2016). The inner disk has a position angle of 110 ± 10° from CO(6-5) kinematics measured with ALMA (Casassus et al. 2015). Its mean radius is estimated to be about 10 au from near-infrared interferometric observations (Anthonioz et al., in prep.). From MIR imaging and SED modeling, Verhoeff et al. (2011) derived a maximum radial extension for the inner disk up to 30 au. However, Avenhaus et al. (2014) imaged the inner circumstellar environment down to ∼0.1″ (15 au) in polarized scattered light with NaCo, but did not detect traces of an inner disk. More recently, Avenhaus et al. (2017) imaged the disk in visible polarized light with SPHERE down to 25 mas (∼4 au) and found evidence for dust scattering close to the star, although it remains unclear if this scattering is related to the inner disk because of geometrical discrepancies with predictions from a modeling of the shadows projected onto the outer disk (Marino et al. 2015). Using our orbital analysis of the companion, we derived the distribution of its separation at periapsis (Fig. 11, right panel) and find a 68% confidence interval of ∼10 − 12 au. This results indicates that the shape of the inner disk is strongly affected by HD 142527B.","Citation Text":["Holman & Wiegert 1999"],"Citation Start End":[[346,367]]} {"Identifier":"2019AandA...622A..9Fukagawa_et_al._2006_Instance_1","Paragraph":"The distributions of separations at apoapsis and periapsis from our LSMC analysis shown in the left panel of Fig. 11 indicate a range at 68%∼18–57 au. If the companion is coplanar with the outer disk, a ∼0.25 M⊙ companion with a 50 au apoapsis and e ∼ 0.5 − 0.7 would in principle create a region of orbital instability extending out to ∼100 au (Holman & Wiegert 1999), which is the innermost possible location for the outer disk (e.g., Fukagawa et al. 2006; Casassus et al. 2012; Rameau et al. 2012; Rodigas et al. 2014; Avenhaus et al. 2017). Nevertheless, the inclination and longitude of node of HD 142527B disagree with those of the outer circumstellar disk (i = 28°, Ω = 160°, Verhoeff et al. 2011; Perez et al. 2015), as has been reported by Lacour et al. (2016). This result would at first sight rule out that HD 142527B is responsible for the outer disk truncation. However, recent hydrodynamical simulations have shown that for an eccentric companion with an almost polar inclination to the outer disk that approaches its periapsis passage, the interactions of companion and disk can reproduce several of the main observed disk features, such as its large cavity, and with the correct position angles, its spiral features and shadows (Price et al. 2018). This orbital configuration is broadly consistent with the results from our orbital analysis. On the other hand, the orbital plane of the companion is close to the plane of the inner circumstellar disk, as previously suggested by Lacour et al. (2016). The inner disk has a position angle of 110 ± 10° from CO(6-5) kinematics measured with ALMA (Casassus et al. 2015). Its mean radius is estimated to be about 10 au from near-infrared interferometric observations (Anthonioz et al., in prep.). From MIR imaging and SED modeling, Verhoeff et al. (2011) derived a maximum radial extension for the inner disk up to 30 au. However, Avenhaus et al. (2014) imaged the inner circumstellar environment down to ∼0.1″ (15 au) in polarized scattered light with NaCo, but did not detect traces of an inner disk. More recently, Avenhaus et al. (2017) imaged the disk in visible polarized light with SPHERE down to 25 mas (∼4 au) and found evidence for dust scattering close to the star, although it remains unclear if this scattering is related to the inner disk because of geometrical discrepancies with predictions from a modeling of the shadows projected onto the outer disk (Marino et al. 2015). Using our orbital analysis of the companion, we derived the distribution of its separation at periapsis (Fig. 11, right panel) and find a 68% confidence interval of ∼10 − 12 au. This results indicates that the shape of the inner disk is strongly affected by HD 142527B.","Citation Text":["Fukagawa et al. 2006"],"Citation Start End":[[437,457]]} {"Identifier":"2019AandA...622A..9Price_et_al._2018_Instance_1","Paragraph":"The distributions of separations at apoapsis and periapsis from our LSMC analysis shown in the left panel of Fig. 11 indicate a range at 68%∼18–57 au. If the companion is coplanar with the outer disk, a ∼0.25 M⊙ companion with a 50 au apoapsis and e ∼ 0.5 − 0.7 would in principle create a region of orbital instability extending out to ∼100 au (Holman & Wiegert 1999), which is the innermost possible location for the outer disk (e.g., Fukagawa et al. 2006; Casassus et al. 2012; Rameau et al. 2012; Rodigas et al. 2014; Avenhaus et al. 2017). Nevertheless, the inclination and longitude of node of HD 142527B disagree with those of the outer circumstellar disk (i = 28°, Ω = 160°, Verhoeff et al. 2011; Perez et al. 2015), as has been reported by Lacour et al. (2016). This result would at first sight rule out that HD 142527B is responsible for the outer disk truncation. However, recent hydrodynamical simulations have shown that for an eccentric companion with an almost polar inclination to the outer disk that approaches its periapsis passage, the interactions of companion and disk can reproduce several of the main observed disk features, such as its large cavity, and with the correct position angles, its spiral features and shadows (Price et al. 2018). This orbital configuration is broadly consistent with the results from our orbital analysis. On the other hand, the orbital plane of the companion is close to the plane of the inner circumstellar disk, as previously suggested by Lacour et al. (2016). The inner disk has a position angle of 110 ± 10° from CO(6-5) kinematics measured with ALMA (Casassus et al. 2015). Its mean radius is estimated to be about 10 au from near-infrared interferometric observations (Anthonioz et al., in prep.). From MIR imaging and SED modeling, Verhoeff et al. (2011) derived a maximum radial extension for the inner disk up to 30 au. However, Avenhaus et al. (2014) imaged the inner circumstellar environment down to ∼0.1″ (15 au) in polarized scattered light with NaCo, but did not detect traces of an inner disk. More recently, Avenhaus et al. (2017) imaged the disk in visible polarized light with SPHERE down to 25 mas (∼4 au) and found evidence for dust scattering close to the star, although it remains unclear if this scattering is related to the inner disk because of geometrical discrepancies with predictions from a modeling of the shadows projected onto the outer disk (Marino et al. 2015). Using our orbital analysis of the companion, we derived the distribution of its separation at periapsis (Fig. 11, right panel) and find a 68% confidence interval of ∼10 − 12 au. This results indicates that the shape of the inner disk is strongly affected by HD 142527B.","Citation Text":["Price et al. 2018"],"Citation Start End":[[1245,1262]]} {"Identifier":"2019AandA...622A..9Avenhaus_et_al._(2014)_Instance_1","Paragraph":"The distributions of separations at apoapsis and periapsis from our LSMC analysis shown in the left panel of Fig. 11 indicate a range at 68%∼18–57 au. If the companion is coplanar with the outer disk, a ∼0.25 M⊙ companion with a 50 au apoapsis and e ∼ 0.5 − 0.7 would in principle create a region of orbital instability extending out to ∼100 au (Holman & Wiegert 1999), which is the innermost possible location for the outer disk (e.g., Fukagawa et al. 2006; Casassus et al. 2012; Rameau et al. 2012; Rodigas et al. 2014; Avenhaus et al. 2017). Nevertheless, the inclination and longitude of node of HD 142527B disagree with those of the outer circumstellar disk (i = 28°, Ω = 160°, Verhoeff et al. 2011; Perez et al. 2015), as has been reported by Lacour et al. (2016). This result would at first sight rule out that HD 142527B is responsible for the outer disk truncation. However, recent hydrodynamical simulations have shown that for an eccentric companion with an almost polar inclination to the outer disk that approaches its periapsis passage, the interactions of companion and disk can reproduce several of the main observed disk features, such as its large cavity, and with the correct position angles, its spiral features and shadows (Price et al. 2018). This orbital configuration is broadly consistent with the results from our orbital analysis. On the other hand, the orbital plane of the companion is close to the plane of the inner circumstellar disk, as previously suggested by Lacour et al. (2016). The inner disk has a position angle of 110 ± 10° from CO(6-5) kinematics measured with ALMA (Casassus et al. 2015). Its mean radius is estimated to be about 10 au from near-infrared interferometric observations (Anthonioz et al., in prep.). From MIR imaging and SED modeling, Verhoeff et al. (2011) derived a maximum radial extension for the inner disk up to 30 au. However, Avenhaus et al. (2014) imaged the inner circumstellar environment down to ∼0.1″ (15 au) in polarized scattered light with NaCo, but did not detect traces of an inner disk. More recently, Avenhaus et al. (2017) imaged the disk in visible polarized light with SPHERE down to 25 mas (∼4 au) and found evidence for dust scattering close to the star, although it remains unclear if this scattering is related to the inner disk because of geometrical discrepancies with predictions from a modeling of the shadows projected onto the outer disk (Marino et al. 2015). Using our orbital analysis of the companion, we derived the distribution of its separation at periapsis (Fig. 11, right panel) and find a 68% confidence interval of ∼10 − 12 au. This results indicates that the shape of the inner disk is strongly affected by HD 142527B.","Citation Text":["Avenhaus et al. (2014)"],"Citation Start End":[[1891,1913]]} {"Identifier":"2022MNRAS.517..632L__Li_2017b_Instance_1","Paragraph":"We first assess the mass–size relation regulated by collision-induced turbulence, i.e. the mass–size relation of clumps in the molecular ring. In our clump–clump collision scenario, the turbulent energy injected by the collisions cascades down to small scales and counterbalances self-gravity to produce a rough virial equilibrium (i.e. the clumps are able to maintain virialization; see Section 5.1). These virialized clumps should always have their energy dissipation rates (per unit mass) $\\dot{\\epsilon }_{\\rm diss,clump}=\\frac{1}{4}\\frac{\\sigma _{\\rm obs,los}^3}{R_{\\rm clump}}$ (equation 14) match their virial energy dissipation rates (per unit mass)\n(33)$$\\begin{eqnarray}\r\n\\dot{\\epsilon }_{\\rm diss,vir} =\\frac{1}{4}\\left(\\alpha _{\\rm vir,crit}\\, GM_{\\rm clump}\/5\\right)^{3\/2}R_{\\rm clump}^{-5\/2}\r\n\\end{eqnarray}$$(Li 2017b), i.e. $\\dot{\\epsilon }_{\\rm diss,clump}\\approx \\dot{\\epsilon }_{\\rm diss,vir}$, where as before αvir, crit ≈ 2 is the boundary between gravitationally bound and unbound objects (Kauffmann et al. 2013, 2017). The virial energy dissipation rate (per unit mass) $\\dot{\\epsilon }_{\\rm diss,vir}$ is the energy dissipation rate (per unit mass) a molecular gas structure would have if it were virialized. We therefore expect\n(34)$$\\begin{eqnarray}\r\n\\dot{\\epsilon }_{\\rm diss,vir}\\approx \\dot{\\epsilon }_{\\rm diss,clump}\\approx \\dot{\\epsilon }_{\\rm inject,coll}\r\n\\end{eqnarray}$$for the clumps in the molecular ring of NGC 404, where we have used $\\dot{\\epsilon }_{\\rm diss,clump}\\approx \\dot{\\epsilon }_{\\rm inject,coll}$, i.e. the energy dissipation rates (per unit mass) of clumps are approximately equal to the energy dissipation rates (per unit mass) from clump–clump collisions in the molecular ring (see Section 4.4). We indeed find very good agreements between the estimated $\\dot{\\epsilon }_{\\rm diss,vir}$, the measured $\\dot{\\epsilon }_{\\rm diss,clump}$, and our predicted $\\dot{\\epsilon }_{\\rm inject,coll}$ in the molecular ring (see panel c of Fig. 9), providing more evidence that the turbulence induced by clump–clump collisions can support and maintain molecular ring clumps in virial equilibrium.","Citation Text":["Li 2017b"],"Citation Start End":[[824,832]]} {"Identifier":"2016MNRAS.455.3820O__Goldreich_&_Julian_1969_Instance_1","Paragraph":"As we see, in the magnetospheres of Crab-like pulsars the Cherenkov drift resonance might lead to the hard X-rays. In the previous section, we have seen that this emission inevitably leads to the non-vanishing pitch angles (see equation 14), generating the synchrotron emission. In Fig. 2 we show the behaviour of energy of synchrotron photons, $\\epsilon _{_{{\\rm GeV}}}$ versus γb in the interval [0.5; 1] × 107 for different values of Lorentz factors of the plasma component: γp = 1 (solid line), γp = 10 (dashed line), γp = 50 (dash–dotted line). We have taken into account the dipolar character of the magnetic field, $B\\approx 3.2\\times 10^{19}\\times \\sqrt{P\\dot{P}}\\times R^3\/R_{lc}^3$ G (Goldreich & Julian 1969), where R = 106 cm is the neutron star's radius. The rest of the parameters is: $P = P_{_{{\\rm Cr}}}$, $\\dot{P}=\\dot{P}_{_{{\\rm Cr}}}$, $n_b = n_{_{GJ}}$, where $n_{_{GJ}} = B\/Pec$ is the Goldreich–Julian number density (Goldreich & Julian 1969). As it is evident from the plots by increasing γp, the resulting emission energy increases as well, which directly follows from the analytical behaviour, $\\epsilon _{_{{\\rm GeV}}}\\propto \\gamma _p^{1\/8}$ (this can be seen by combining equations 8, 12–14). We see that the QLD by means of the feedback of ChDI guarantees the synchrotron emission over 100 GeV. We can roughly estimate the possible VHE luminosity by multiplying the number of particles involved in the process with the single emission power, $P_{{\\rm syn}}\\approx 2e^4\\gamma _b^2B^2\\langle \\psi \\rangle ^2\/3m^2c^3$. It is worth noting that the thickness of the layer, d, where the electrons accelerate to the highest energies, is of the order of Rlc\/2γb. Then, by taking into account the corresponding number of particles, $4\\pi R_{lc}^2n_{_{GJ}}d$, one can show that in the emission energy band 150 GeV the highest energy electrons lead to the bulk luminosity of the order of 1033 erg s−1 which is in a good agreement with observations (Lessard et al. 2000; Albert et al. 2008).","Citation Text":["Goldreich & Julian 1969"],"Citation Start End":[[695,718]]} {"Identifier":"2016MNRAS.455.3820O__Goldreich_&_Julian_1969_Instance_2","Paragraph":"As we see, in the magnetospheres of Crab-like pulsars the Cherenkov drift resonance might lead to the hard X-rays. In the previous section, we have seen that this emission inevitably leads to the non-vanishing pitch angles (see equation 14), generating the synchrotron emission. In Fig. 2 we show the behaviour of energy of synchrotron photons, $\\epsilon _{_{{\\rm GeV}}}$ versus γb in the interval [0.5; 1] × 107 for different values of Lorentz factors of the plasma component: γp = 1 (solid line), γp = 10 (dashed line), γp = 50 (dash–dotted line). We have taken into account the dipolar character of the magnetic field, $B\\approx 3.2\\times 10^{19}\\times \\sqrt{P\\dot{P}}\\times R^3\/R_{lc}^3$ G (Goldreich & Julian 1969), where R = 106 cm is the neutron star's radius. The rest of the parameters is: $P = P_{_{{\\rm Cr}}}$, $\\dot{P}=\\dot{P}_{_{{\\rm Cr}}}$, $n_b = n_{_{GJ}}$, where $n_{_{GJ}} = B\/Pec$ is the Goldreich–Julian number density (Goldreich & Julian 1969). As it is evident from the plots by increasing γp, the resulting emission energy increases as well, which directly follows from the analytical behaviour, $\\epsilon _{_{{\\rm GeV}}}\\propto \\gamma _p^{1\/8}$ (this can be seen by combining equations 8, 12–14). We see that the QLD by means of the feedback of ChDI guarantees the synchrotron emission over 100 GeV. We can roughly estimate the possible VHE luminosity by multiplying the number of particles involved in the process with the single emission power, $P_{{\\rm syn}}\\approx 2e^4\\gamma _b^2B^2\\langle \\psi \\rangle ^2\/3m^2c^3$. It is worth noting that the thickness of the layer, d, where the electrons accelerate to the highest energies, is of the order of Rlc\/2γb. Then, by taking into account the corresponding number of particles, $4\\pi R_{lc}^2n_{_{GJ}}d$, one can show that in the emission energy band 150 GeV the highest energy electrons lead to the bulk luminosity of the order of 1033 erg s−1 which is in a good agreement with observations (Lessard et al. 2000; Albert et al. 2008).","Citation Text":["Goldreich & Julian 1969"],"Citation Start End":[[940,963]]} {"Identifier":"2016MNRAS.455.3820OLessard_et_al._2000_Instance_1","Paragraph":"As we see, in the magnetospheres of Crab-like pulsars the Cherenkov drift resonance might lead to the hard X-rays. In the previous section, we have seen that this emission inevitably leads to the non-vanishing pitch angles (see equation 14), generating the synchrotron emission. In Fig. 2 we show the behaviour of energy of synchrotron photons, $\\epsilon _{_{{\\rm GeV}}}$ versus γb in the interval [0.5; 1] × 107 for different values of Lorentz factors of the plasma component: γp = 1 (solid line), γp = 10 (dashed line), γp = 50 (dash–dotted line). We have taken into account the dipolar character of the magnetic field, $B\\approx 3.2\\times 10^{19}\\times \\sqrt{P\\dot{P}}\\times R^3\/R_{lc}^3$ G (Goldreich & Julian 1969), where R = 106 cm is the neutron star's radius. The rest of the parameters is: $P = P_{_{{\\rm Cr}}}$, $\\dot{P}=\\dot{P}_{_{{\\rm Cr}}}$, $n_b = n_{_{GJ}}$, where $n_{_{GJ}} = B\/Pec$ is the Goldreich–Julian number density (Goldreich & Julian 1969). As it is evident from the plots by increasing γp, the resulting emission energy increases as well, which directly follows from the analytical behaviour, $\\epsilon _{_{{\\rm GeV}}}\\propto \\gamma _p^{1\/8}$ (this can be seen by combining equations 8, 12–14). We see that the QLD by means of the feedback of ChDI guarantees the synchrotron emission over 100 GeV. We can roughly estimate the possible VHE luminosity by multiplying the number of particles involved in the process with the single emission power, $P_{{\\rm syn}}\\approx 2e^4\\gamma _b^2B^2\\langle \\psi \\rangle ^2\/3m^2c^3$. It is worth noting that the thickness of the layer, d, where the electrons accelerate to the highest energies, is of the order of Rlc\/2γb. Then, by taking into account the corresponding number of particles, $4\\pi R_{lc}^2n_{_{GJ}}d$, one can show that in the emission energy band 150 GeV the highest energy electrons lead to the bulk luminosity of the order of 1033 erg s−1 which is in a good agreement with observations (Lessard et al. 2000; Albert et al. 2008).","Citation Text":["Lessard et al. 2000"],"Citation Start End":[[1967,1986]]} {"Identifier":"2017AandA...607A..20T__Wirstrom_et_al._(2014)_Instance_1","Paragraph":"The Barnard 5 (B5) dark cloud is located at the North-East of the Perseus complex (235 pc; Hirota et al. 2008). It contains four known protostars of which the most prominent is the Class I protostar IRS1. SCUBA continuum emission maps at 850 μm carried out with the JCMT only revealed dust emission towards known protostars and at about 2–4 arcmin north from IRS 1 (Hatchell et al. 2005) whilst molecular maps of CO, NH3, and other species show several chemically differentiated clumps (S. B. Charnley, in prep.). Methanol emission in B5 displays a particularly interesting distribution since it shows a bright so-called methanol hotspot at about 250 arcsec north-west from IRS 1, a region showing no infrared sources and no detected sub-mm continuum emission (see Fig. 1 in Hatchell et al. 2005; Wirstrom et al. 2014). The subsequent detection of abundant water, with absolute abundances of about 10-8, with the Herschel Space Observatory by Wirstrom et al. (2014) suggests that efficient non-thermal processes triggering the evaporation of icy methanol and water are at work. The methanol hotspot therefore represents an ideal target to detect cold COMs in dark clouds since they are supposed to be formed from methanol, either at the surface of interstellar grains, or directly in the gas phase after the evaporation of methanol. The Perseus molecular cloud was recently mapped with Herschel as part as the Gould Belt Survey key program (André et al. 2010) using the photometers PACS and SPIRE in five bands between 70 μm and 500 μm.Figure 1 presents the Barnard 5 molecular cloud as seen by Herschel\/SPIRE at 250 μm. The Herschel data has been retrieved from the Herschel Science Archive. The data were calibrated and processed with the Herschel pipeline and are considered as a level-3 data product. Dust emission is compared with the integrated intensity map of the A+-CH3OH 30 − 20 transition as observed with the IRAM 30 m telescope (this work).The methanol hotspot is located between the two dense cores East 189 and East 286 (Sadavoy, priv. comm.) revealed by Herschel for the first time, and the methanol emission peaks at the edge of core East 189. East 189 and East 286 have the following properties derived through a fitting of their observed spectral energy distribution: M = 0.5M⊙, Td = 12 K, R = 3.6 × 10-2 pc, nH = 3 × 104 cm-3, and M = 0.7M⊙, Td = 9.9 K, R = 2.7 × 10-2 pc, nH = 1.2 × 105 cm-3 (Sadavoy 2013).","Citation Text":["Wirstrom et al. 2014"],"Citation Start End":[[797,817]]} {"Identifier":"2017AandA...607A..20T__Wirstrom_et_al._(2014)_Instance_2","Paragraph":"The Barnard 5 (B5) dark cloud is located at the North-East of the Perseus complex (235 pc; Hirota et al. 2008). It contains four known protostars of which the most prominent is the Class I protostar IRS1. SCUBA continuum emission maps at 850 μm carried out with the JCMT only revealed dust emission towards known protostars and at about 2–4 arcmin north from IRS 1 (Hatchell et al. 2005) whilst molecular maps of CO, NH3, and other species show several chemically differentiated clumps (S. B. Charnley, in prep.). Methanol emission in B5 displays a particularly interesting distribution since it shows a bright so-called methanol hotspot at about 250 arcsec north-west from IRS 1, a region showing no infrared sources and no detected sub-mm continuum emission (see Fig. 1 in Hatchell et al. 2005; Wirstrom et al. 2014). The subsequent detection of abundant water, with absolute abundances of about 10-8, with the Herschel Space Observatory by Wirstrom et al. (2014) suggests that efficient non-thermal processes triggering the evaporation of icy methanol and water are at work. The methanol hotspot therefore represents an ideal target to detect cold COMs in dark clouds since they are supposed to be formed from methanol, either at the surface of interstellar grains, or directly in the gas phase after the evaporation of methanol. The Perseus molecular cloud was recently mapped with Herschel as part as the Gould Belt Survey key program (André et al. 2010) using the photometers PACS and SPIRE in five bands between 70 μm and 500 μm.Figure 1 presents the Barnard 5 molecular cloud as seen by Herschel\/SPIRE at 250 μm. The Herschel data has been retrieved from the Herschel Science Archive. The data were calibrated and processed with the Herschel pipeline and are considered as a level-3 data product. Dust emission is compared with the integrated intensity map of the A+-CH3OH 30 − 20 transition as observed with the IRAM 30 m telescope (this work).The methanol hotspot is located between the two dense cores East 189 and East 286 (Sadavoy, priv. comm.) revealed by Herschel for the first time, and the methanol emission peaks at the edge of core East 189. East 189 and East 286 have the following properties derived through a fitting of their observed spectral energy distribution: M = 0.5M⊙, Td = 12 K, R = 3.6 × 10-2 pc, nH = 3 × 104 cm-3, and M = 0.7M⊙, Td = 9.9 K, R = 2.7 × 10-2 pc, nH = 1.2 × 105 cm-3 (Sadavoy 2013).","Citation Text":["Wirstrom et al. (2014)"],"Citation Start End":[[943,965]]} {"Identifier":"2017AandA...607A..2Hirota_et_al._2008_Instance_1","Paragraph":"The Barnard 5 (B5) dark cloud is located at the North-East of the Perseus complex (235 pc; Hirota et al. 2008). It contains four known protostars of which the most prominent is the Class I protostar IRS1. SCUBA continuum emission maps at 850 μm carried out with the JCMT only revealed dust emission towards known protostars and at about 2–4 arcmin north from IRS 1 (Hatchell et al. 2005) whilst molecular maps of CO, NH3, and other species show several chemically differentiated clumps (S. B. Charnley, in prep.). Methanol emission in B5 displays a particularly interesting distribution since it shows a bright so-called methanol hotspot at about 250 arcsec north-west from IRS 1, a region showing no infrared sources and no detected sub-mm continuum emission (see Fig. 1 in Hatchell et al. 2005; Wirstrom et al. 2014). The subsequent detection of abundant water, with absolute abundances of about 10-8, with the Herschel Space Observatory by Wirstrom et al. (2014) suggests that efficient non-thermal processes triggering the evaporation of icy methanol and water are at work. The methanol hotspot therefore represents an ideal target to detect cold COMs in dark clouds since they are supposed to be formed from methanol, either at the surface of interstellar grains, or directly in the gas phase after the evaporation of methanol. The Perseus molecular cloud was recently mapped with Herschel as part as the Gould Belt Survey key program (André et al. 2010) using the photometers PACS and SPIRE in five bands between 70 μm and 500 μm.Figure 1 presents the Barnard 5 molecular cloud as seen by Herschel\/SPIRE at 250 μm. The Herschel data has been retrieved from the Herschel Science Archive. The data were calibrated and processed with the Herschel pipeline and are considered as a level-3 data product. Dust emission is compared with the integrated intensity map of the A+-CH3OH 30 − 20 transition as observed with the IRAM 30 m telescope (this work).The methanol hotspot is located between the two dense cores East 189 and East 286 (Sadavoy, priv. comm.) revealed by Herschel for the first time, and the methanol emission peaks at the edge of core East 189. East 189 and East 286 have the following properties derived through a fitting of their observed spectral energy distribution: M = 0.5M⊙, Td = 12 K, R = 3.6 × 10-2 pc, nH = 3 × 104 cm-3, and M = 0.7M⊙, Td = 9.9 K, R = 2.7 × 10-2 pc, nH = 1.2 × 105 cm-3 (Sadavoy 2013).","Citation Text":["Hirota et al. 2008"],"Citation Start End":[[91,109]]} {"Identifier":"2017AandA...607A..2Sadavoy__2013_Instance_1","Paragraph":"The Barnard 5 (B5) dark cloud is located at the North-East of the Perseus complex (235 pc; Hirota et al. 2008). It contains four known protostars of which the most prominent is the Class I protostar IRS1. SCUBA continuum emission maps at 850 μm carried out with the JCMT only revealed dust emission towards known protostars and at about 2–4 arcmin north from IRS 1 (Hatchell et al. 2005) whilst molecular maps of CO, NH3, and other species show several chemically differentiated clumps (S. B. Charnley, in prep.). Methanol emission in B5 displays a particularly interesting distribution since it shows a bright so-called methanol hotspot at about 250 arcsec north-west from IRS 1, a region showing no infrared sources and no detected sub-mm continuum emission (see Fig. 1 in Hatchell et al. 2005; Wirstrom et al. 2014). The subsequent detection of abundant water, with absolute abundances of about 10-8, with the Herschel Space Observatory by Wirstrom et al. (2014) suggests that efficient non-thermal processes triggering the evaporation of icy methanol and water are at work. The methanol hotspot therefore represents an ideal target to detect cold COMs in dark clouds since they are supposed to be formed from methanol, either at the surface of interstellar grains, or directly in the gas phase after the evaporation of methanol. The Perseus molecular cloud was recently mapped with Herschel as part as the Gould Belt Survey key program (André et al. 2010) using the photometers PACS and SPIRE in five bands between 70 μm and 500 μm.Figure 1 presents the Barnard 5 molecular cloud as seen by Herschel\/SPIRE at 250 μm. The Herschel data has been retrieved from the Herschel Science Archive. The data were calibrated and processed with the Herschel pipeline and are considered as a level-3 data product. Dust emission is compared with the integrated intensity map of the A+-CH3OH 30 − 20 transition as observed with the IRAM 30 m telescope (this work).The methanol hotspot is located between the two dense cores East 189 and East 286 (Sadavoy, priv. comm.) revealed by Herschel for the first time, and the methanol emission peaks at the edge of core East 189. East 189 and East 286 have the following properties derived through a fitting of their observed spectral energy distribution: M = 0.5M⊙, Td = 12 K, R = 3.6 × 10-2 pc, nH = 3 × 104 cm-3, and M = 0.7M⊙, Td = 9.9 K, R = 2.7 × 10-2 pc, nH = 1.2 × 105 cm-3 (Sadavoy 2013).","Citation Text":["Sadavoy 2013"],"Citation Start End":[[2414,2427]]} {"Identifier":"2017ApJ...837..109L__Storey_&_Zeippen_2000_Instance_1","Paragraph":"Next, we fit the emission lines using the code described in detail in Dong et al. (2005). The optical spectra show strong, narrow emission lines such as [O ii] λ3727, [O i]\n\n\n\n\n\n, \n\n\n\n\n\n, [N ii]\n\n\n\n\n\n, and [S ii]\n\n\n\n\n\n [O iii]\n\n\n\n\n\n is instead weak. As we verified above, broad \n\n\n\n\n\n is evidently presented (see also Greene & Ho 2007; Dong et al. 2012). The SDSS data are used to fit the blue part such as in the \n\n\n\n\n\n+[O iii] region (as not covered by the MMT spectrum), and the MMT data for the red part such as [O i] lines, the \n\n\n\n\n\n+[N ii] region, and [S ii] lines. We fit the MMT spectrum first. Every narrow or broad component of the emission lines is modeled with Gaussians, starting with one Gaussian and adding in more if the fit can be improved significantly according to the F-test. The [S ii]\n\n\n\n\n\n doublet lines are assumed to have the same profile and fixed in separation by their laboratory wavelength; the same is applied to [N ii]\n\n\n\n\n\n doublet lines, and to [O i]\n\n\n\n\n\n and [O i]\n\n\n\n\n\n emission lines. The flux ratio of the [N ii] doublet \n\n\n\n\n\n is fixed to the theoretical value of 2.96 (e.g., Acker et al. 1989; Storey & Zeippen 2000). In the best-fit model, it turns out that one Gaussian is used for the broad component of \n\n\n\n\n\n, while two Gaussians for the narrow component of \n\n\n\n\n\n, each line of the [N ii], and [S ii] doublet and the two [O i] lines, respectively. The reduced \n\n\n\n\n\n is 1.21 for the \n\n\n\n\n\n+[N ii] region. Note that the [N ii]\n\n\n\n\n\n and [S ii] doublet lines show asymmetric line profiles clearly in the MMT spectrum, which are actually common in high-resolution spectra (Xiao et al. 2011); thus these narrow lines, and narrow \n\n\n\n\n\n also, need two Gaussians to model. Then we fit the \n\n\n\n\n\n+[O iii] region based on the SDSS spectrum. As the spectral signal-to-noise (S\/N) of this region is not high and the \n\n\n\n\n\n emission line is much weaker than \n\n\n\n\n\n, we assume the broad and narrow components of \n\n\n\n\n\n have the same profiles as the respective components of \n\n\n\n\n\n. The [O iii]\n\n\n\n\n\n doublet lines are assumed to have the same profile, and the flux ratio of \n\n\n\n\n\n is fixed to the theoretical value of 2.98 (e.g., Storey & Zeippen 2000; Dimitrijević et al. 2007); the best-fit model turns out to adopt two Gaussians for each [O iii] doublet line. The reduced \n\n\n\n\n\n is 0.95 for the \n\n\n\n\n\n+[O iii] region. [O ii] λ3727 is fit independently, and one Gaussian is sufficient to model. We also fit the \n\n\n\n\n\n lines of the N and S branches of the extended emission. One Gaussian is statistically sufficient for either branch, with reduced \n\n\n\n\n\n of 0.95 (N) and 0.97 (S), respectively. The best-fit line parameters, centroid, FWHM (corrected for instrumental broadening), and flux of every branch agree well with those directly integrated\/measured from the spectra.","Citation Text":["Storey & Zeippen 2000"],"Citation Start End":[[1135,1156]]} {"Identifier":"2017ApJ...837..109L__Storey_&_Zeippen_2000_Instance_2","Paragraph":"Next, we fit the emission lines using the code described in detail in Dong et al. (2005). The optical spectra show strong, narrow emission lines such as [O ii] λ3727, [O i]\n\n\n\n\n\n, \n\n\n\n\n\n, [N ii]\n\n\n\n\n\n, and [S ii]\n\n\n\n\n\n [O iii]\n\n\n\n\n\n is instead weak. As we verified above, broad \n\n\n\n\n\n is evidently presented (see also Greene & Ho 2007; Dong et al. 2012). The SDSS data are used to fit the blue part such as in the \n\n\n\n\n\n+[O iii] region (as not covered by the MMT spectrum), and the MMT data for the red part such as [O i] lines, the \n\n\n\n\n\n+[N ii] region, and [S ii] lines. We fit the MMT spectrum first. Every narrow or broad component of the emission lines is modeled with Gaussians, starting with one Gaussian and adding in more if the fit can be improved significantly according to the F-test. The [S ii]\n\n\n\n\n\n doublet lines are assumed to have the same profile and fixed in separation by their laboratory wavelength; the same is applied to [N ii]\n\n\n\n\n\n doublet lines, and to [O i]\n\n\n\n\n\n and [O i]\n\n\n\n\n\n emission lines. The flux ratio of the [N ii] doublet \n\n\n\n\n\n is fixed to the theoretical value of 2.96 (e.g., Acker et al. 1989; Storey & Zeippen 2000). In the best-fit model, it turns out that one Gaussian is used for the broad component of \n\n\n\n\n\n, while two Gaussians for the narrow component of \n\n\n\n\n\n, each line of the [N ii], and [S ii] doublet and the two [O i] lines, respectively. The reduced \n\n\n\n\n\n is 1.21 for the \n\n\n\n\n\n+[N ii] region. Note that the [N ii]\n\n\n\n\n\n and [S ii] doublet lines show asymmetric line profiles clearly in the MMT spectrum, which are actually common in high-resolution spectra (Xiao et al. 2011); thus these narrow lines, and narrow \n\n\n\n\n\n also, need two Gaussians to model. Then we fit the \n\n\n\n\n\n+[O iii] region based on the SDSS spectrum. As the spectral signal-to-noise (S\/N) of this region is not high and the \n\n\n\n\n\n emission line is much weaker than \n\n\n\n\n\n, we assume the broad and narrow components of \n\n\n\n\n\n have the same profiles as the respective components of \n\n\n\n\n\n. The [O iii]\n\n\n\n\n\n doublet lines are assumed to have the same profile, and the flux ratio of \n\n\n\n\n\n is fixed to the theoretical value of 2.98 (e.g., Storey & Zeippen 2000; Dimitrijević et al. 2007); the best-fit model turns out to adopt two Gaussians for each [O iii] doublet line. The reduced \n\n\n\n\n\n is 0.95 for the \n\n\n\n\n\n+[O iii] region. [O ii] λ3727 is fit independently, and one Gaussian is sufficient to model. We also fit the \n\n\n\n\n\n lines of the N and S branches of the extended emission. One Gaussian is statistically sufficient for either branch, with reduced \n\n\n\n\n\n of 0.95 (N) and 0.97 (S), respectively. The best-fit line parameters, centroid, FWHM (corrected for instrumental broadening), and flux of every branch agree well with those directly integrated\/measured from the spectra.","Citation Text":["Storey & Zeippen 2000"],"Citation Start End":[[2165,2186]]} {"Identifier":"2015ApJ...807L..14N__McKinney_et_al._2013_Instance_1","Paragraph":"The de-projected distance that corresponds to the core-position changes of Markarian 421 is approximately 3.5 ∼ 8.7 pc (equivalent to (1.0 − 2.6) × 105 Schwarzschild radii (Rs)) for a jet-viewing angle of 2°–5° (Lico et al. 2012). One of the leading models for explaining the blazar phenomenon is the so-called internal-shock model, in which discrete ejecta with higher speeds catch up with the preceding slower ejecta, and the collision leads to a shock wave in the colliding ejecta (Spada et al. 2001; Guetta et al. 2004). Based on this model, core wandering can be naturally explained because the model predicts some scattering of the shock locations caused by the randomness of the ejecta speed. Therefore, we assume that the distances of the shock locations from the black hole immediately after the flare, \n\n\n\n\n\n, are proportional to the product of the square of the bulk Lorentz factor (\n\n\n\n\n\n) of the ejecta and the separation length (Δ) of the colliding ejecta. Assuming that a typical separation length is a scale of about 10 times the innermost stable circular orbit for non-rotating black holes (\n\n\n\n\n\n), in light of numerical simulations of relativistic outflows around black holes (McKinney et al. 2013), very fast ejecta with a Lorentz factor of approximately \n\n\n\n\n\n are required to explain the observed magnitude of the core wandering. The \n\n\n\n\n\n is comparable to previously reported maximum values (Γ of 40 ∼ 50; Lister et al. 2009, 2013) based on statistical studies by a long-term monitor using VLBI. Moreover, the radio core returned to the reference stationary position after 2012 March 12 (the 10th epoch). This can be explained if the emission from the reference position is identical to the radio core that is in a quiescent state. The radio-core emission in a quiescent state is expected to be persistent. As one of the possibilities for reproducing the observed core wandering, this persistent radio core was obscured by the flare-associated radio core, which therefore must be optically thick against SSA and short lived (a lifetime of approximately 2 weeks), for several epochs. Such a flare-associated radio core must be located at least \n\n\n\n\n\n downstream from the persistent radio core. In addition, Koyama et al. (2015) recently conducted multi-epoch astrometric observations of Markarian 501, which is also one of the most nearby TeV blazars by using VERA. However, they detected no significant positional changes of the radio core during its quiescent state. This fact, therefore, seems to support the radio core wandering seen after the large X-ray flare.","Citation Text":["McKinney et al. 2013"],"Citation Start End":[[1196,1216]]} {"Identifier":"2016AandA...589A..29W__Tielens_2005_Instance_1","Paragraph":"In addition to the processes that release SiO into the gas phase, it is also important to\n discuss the properties of the responsible shock. Shocks are divided into three types: jump\n shocks (J-type, Hollenbach & McKee 1979),\n continuous shocks (C-type, Draine 1980), and a\n mixture of both, which is a C-type shock with an introduced discontinuity (CJ-type, Chieze et al. 1998). The type of shock depends mainly on\n the presence of a magnetic field, since a magnetic field is necessary for the shock\n condition to become continuous, the ionization of the preshock gas, since only charged\n particles couple to the magnetic field, and on the velocity of the shock, since J-type\n shocks can have higher velocities than C-type shocks (Flower\n & Pineau des Forêts 2003; Tielens 2005;\n Anderl et al. 2013). A main difference between the\n types is that J shocks lead to partial or complete dissociation of molecules, such as\n molecular hydrogen. Because we observed a lot of H2 emission (see Fig. 3), pure J shocks are fairly improbable in this case, since they would dissociate\n the molecular hydrogen. Studies by Gusdorf et al.\n (2008b) have shown that even CJ-type shocks at a velocity of 25 km s-1 are energetic enough to\n dissociate the ambient hydrogen. However, in a more recent paper, Gusdorf et al. (2015) have found that CJ-type shocks reproduce\n H2 observations\n even better. They found that C-type shocks are not able to reproduce their H2 excitation temperatures. In\n conclusion, the strong observed H2 emission suggests that we are not observing J-type shocks;\n however, we cannot differentiate further between C-type or CJ-type shocks with the present\n data. Another important parameter of the shocks is the velocity. However, it is very\n difficult to estimate the shock velocity in the current case. The SiO signal in the line\n wings is present until 15 km s-1 apart from the rest velocity. This is most likely not the\n maximum shock velocity, as the strong SiO signal at ambient velocity indicates jets or\n outflows with a large velocity component in the plane of the sky. In conclusion, this means\n that SiO emission in this case can be the effect of shocks with comparably high velocities\n (vshock>\n 25 km s-1), because the expected C-type or CJ-type shocks can reach\n very high velocities, depending on the preshock density (Le\n Bourlot et al. 2002). These shocks would most likely be a result of the ongoing\n star formation. However, low-velocity shocks are also able to release the SiO if it is\n present in the core mantles. ","Citation Text":["Tielens 2005"],"Citation Start End":[[830,842]]} {"Identifier":"2017MNRAS.470.3388P__Fabian_2006_Instance_1","Paragraph":"X-ray radiation observed from clusters of galaxies is emitted by hot, low-density and metal-enriched plasmas filling the space between galaxies (for a review, see Sarazin 1986). We focus attention on relaxed galaxy clusters that are not disturbed by ongoing mergers with other groups (or clusters) of galaxies. The measured X-ray surface brightness and derived plasma density profiles of such clusters are sharply centrally peaked and decrease with radius, while the derived plasma temperature profiles have minima at the centres (for a review, see e.g. Peterson Fabian 2006, and references therein). These central low-temperature dense regions are coined as cool-cores (Molendi Pizzolato 2001, formerly known as cooling flows) and galaxy clusters having cool cores are called cool-core clusters. If no external energy sources are present in cool cores, the radiative losses in clusters centres would lead to gas cooling well below X-ray temperatures in a fraction of the Hubble time. The absence of the low temperature emission lines in the spectra of cool-core clusters (e.g. Tamura etal. 2001) and the lack of intense star formation suggest that external energy sources for plasma heating do exist in the cool cores. A likely explanation is that the energy produced by the central active galactic nuclei (AGNs) balances radiative losses of the X-ray emitting plasma (e.g. Churazov etal. 2000; McNamara etal. 2000). The activity of the central AGNs manifests itself via the presence of X-ray cavities (or bubbles) inflated by relativistic outflows from the AGNs that are present in majority of cool-core clusters (for a review, see Fabian 2012; Bykov etal. 2015). These bubbles are typically bright in the radio band (e.g. Boehringer etal. 1993), implying that relativistic electrons (and, perhaps, positrons) are present inside them. The bubbles rise buoyantly in cluster atmospheres and pure mechanical interaction can provide efficient energy transfer from the bubble enthalpy to the gas (e.g. Churazov etal. 2000, 2001, 2002). These buoyancy arguments suggest that the energy supplied by the AGNs matches approximately the gas cooling losses. This conclusion has been confirmed by the analysis of many systems that differ in X-ray luminosity by several orders of magnitude (e.g. Brzan etal. 2004; Hlavacek-Larrondo etal. 2012).","Citation Text":["Peterson Fabian 2006"],"Citation Start End":[[554,575]]} {"Identifier":"2017MNRAS.470..350Y__Cutler_&_Flanagan_1994_Instance_1","Paragraph":"Similar to Balachandran & Flanagan (2007), who also studied the detectability of mode resonances (see also Flanagan & Racine 2007), we assume that the frequency-domain GW signal has the form\n(30)\r\n\\begin{equation}\r\n\\tilde{h}(f) = \\mathcal {A} f^{-7\/6} \\text{e}^{\\text{i}\\Psi (f)},\r\n\\end{equation}\r\nwhere the amplitude (Maggiore 2007)\n(31)\r\n\\begin{equation}\r\n\\mathcal {A}=\\left(\\frac{5}{24\\pi ^{4\/3}}\\right)^{1\/2}\\left(\\frac{G\\mathcal {M}}{c^3}\\right)^{-5\/6}\\frac{\\mathcal {K}}{d}.\r\n\\end{equation}\r\nHere $\\mathcal {M}=[(M M^{\\prime })^{3}\/(M+M^{\\prime })]^{1\/5}$ is the chirp mass, d is the distance to the source and $\\mathcal {K}$ is the antenna response (for an optimally oriented source $\\mathcal {K}=1$). Our model of the phase evolution Ψ(f) accounts for the zeroth-order post-Newtonian point-particle contribution and for the resonant tidal excitation of individual g-modes. We ignore higher order post-Newtonian terms, spin, the equilibrium tide and non-linear tidal effects (such as those considered in Essick, Vitale & Weinberg 2016), and assume that the signal shuts off at the GW frequency corresponding to the innermost stable circular orbit f = 2fISCO ≃ 1.6 × 103 Hz [2.8 M⊙\/(M + M΄)] (Cutler & Flanagan 1994; Poisson & Will 1995). In Appendix B, we show that under these assumptions,\n(32)\r\n\\begin{equation}\r\n\\Psi (f) = \\Psi _{\\rm pp}(f) - \\sum _a\\left(1-\\frac{f}{f_a}\\right) \\delta \\phi _a \\Theta \\left(f-f_a\\right),\r\n\\end{equation}\r\nwhere, by the stationary-phase approximation, the point-particle phase is (Cutler & Flanagan 1994)\n(33)\r\n\\begin{equation}\r\n\\Psi _{\\rm pp}(f) = 2\\pi f t_{\\rm c} -\\phi _{\\rm c}-\\frac{\\pi }{4} +\\frac{3}{4}\\left(\\frac{8\\pi G\\mathcal {M}f}{c^3}\\right)^{-5\/3},\r\n\\end{equation}\r\nδϕa is the phase shift due to the tidal resonance with a mode a with eigenfrequency fa, and Θ(f − fa) is the Heaviside step function. Here tc and ϕc are constants of integration that set a reference time and phase. The duration of each resonance is, in general, much shorter than the orbital decay time-scale due to radiation reaction (their ratio is ${\\simeq } 0.1\\times [(\\mathcal {M}\/1.2\\,\\mathrm{M}_{\\odot })(f\/500 \\text{ Hz})]^{5\/6}$; see Lai 1994; Balachandran & Flanagan 2007; Flanagan & Racine 2007). We therefore model the resonance as an instantaneous process, which should be a good approximation since nearly all the g-modes we consider have $f_a^{\\rm (GR)} < 500\\,{\\rm Hz}$ (the one exception is the na = 1 hyperonic g-mode of the 1.6 M⊙ HS model which has $f_a^{\\rm (GR)}=740\\,{\\rm Hz}$).","Citation Text":["Cutler & Flanagan 1994"],"Citation Start End":[[1199,1221]]} {"Identifier":"2017MNRAS.470..350Y__Cutler_&_Flanagan_1994_Instance_2","Paragraph":"Similar to Balachandran & Flanagan (2007), who also studied the detectability of mode resonances (see also Flanagan & Racine 2007), we assume that the frequency-domain GW signal has the form\n(30)\r\n\\begin{equation}\r\n\\tilde{h}(f) = \\mathcal {A} f^{-7\/6} \\text{e}^{\\text{i}\\Psi (f)},\r\n\\end{equation}\r\nwhere the amplitude (Maggiore 2007)\n(31)\r\n\\begin{equation}\r\n\\mathcal {A}=\\left(\\frac{5}{24\\pi ^{4\/3}}\\right)^{1\/2}\\left(\\frac{G\\mathcal {M}}{c^3}\\right)^{-5\/6}\\frac{\\mathcal {K}}{d}.\r\n\\end{equation}\r\nHere $\\mathcal {M}=[(M M^{\\prime })^{3}\/(M+M^{\\prime })]^{1\/5}$ is the chirp mass, d is the distance to the source and $\\mathcal {K}$ is the antenna response (for an optimally oriented source $\\mathcal {K}=1$). Our model of the phase evolution Ψ(f) accounts for the zeroth-order post-Newtonian point-particle contribution and for the resonant tidal excitation of individual g-modes. We ignore higher order post-Newtonian terms, spin, the equilibrium tide and non-linear tidal effects (such as those considered in Essick, Vitale & Weinberg 2016), and assume that the signal shuts off at the GW frequency corresponding to the innermost stable circular orbit f = 2fISCO ≃ 1.6 × 103 Hz [2.8 M⊙\/(M + M΄)] (Cutler & Flanagan 1994; Poisson & Will 1995). In Appendix B, we show that under these assumptions,\n(32)\r\n\\begin{equation}\r\n\\Psi (f) = \\Psi _{\\rm pp}(f) - \\sum _a\\left(1-\\frac{f}{f_a}\\right) \\delta \\phi _a \\Theta \\left(f-f_a\\right),\r\n\\end{equation}\r\nwhere, by the stationary-phase approximation, the point-particle phase is (Cutler & Flanagan 1994)\n(33)\r\n\\begin{equation}\r\n\\Psi _{\\rm pp}(f) = 2\\pi f t_{\\rm c} -\\phi _{\\rm c}-\\frac{\\pi }{4} +\\frac{3}{4}\\left(\\frac{8\\pi G\\mathcal {M}f}{c^3}\\right)^{-5\/3},\r\n\\end{equation}\r\nδϕa is the phase shift due to the tidal resonance with a mode a with eigenfrequency fa, and Θ(f − fa) is the Heaviside step function. Here tc and ϕc are constants of integration that set a reference time and phase. The duration of each resonance is, in general, much shorter than the orbital decay time-scale due to radiation reaction (their ratio is ${\\simeq } 0.1\\times [(\\mathcal {M}\/1.2\\,\\mathrm{M}_{\\odot })(f\/500 \\text{ Hz})]^{5\/6}$; see Lai 1994; Balachandran & Flanagan 2007; Flanagan & Racine 2007). We therefore model the resonance as an instantaneous process, which should be a good approximation since nearly all the g-modes we consider have $f_a^{\\rm (GR)} < 500\\,{\\rm Hz}$ (the one exception is the na = 1 hyperonic g-mode of the 1.6 M⊙ HS model which has $f_a^{\\rm (GR)}=740\\,{\\rm Hz}$).","Citation Text":["Cutler & Flanagan 1994"],"Citation Start End":[[1523,1545]]} {"Identifier":"2017MNRAS.470..350YBalachandran_&_Flanagan_(2007)_Instance_1","Paragraph":"Similar to Balachandran & Flanagan (2007), who also studied the detectability of mode resonances (see also Flanagan & Racine 2007), we assume that the frequency-domain GW signal has the form\n(30)\r\n\\begin{equation}\r\n\\tilde{h}(f) = \\mathcal {A} f^{-7\/6} \\text{e}^{\\text{i}\\Psi (f)},\r\n\\end{equation}\r\nwhere the amplitude (Maggiore 2007)\n(31)\r\n\\begin{equation}\r\n\\mathcal {A}=\\left(\\frac{5}{24\\pi ^{4\/3}}\\right)^{1\/2}\\left(\\frac{G\\mathcal {M}}{c^3}\\right)^{-5\/6}\\frac{\\mathcal {K}}{d}.\r\n\\end{equation}\r\nHere $\\mathcal {M}=[(M M^{\\prime })^{3}\/(M+M^{\\prime })]^{1\/5}$ is the chirp mass, d is the distance to the source and $\\mathcal {K}$ is the antenna response (for an optimally oriented source $\\mathcal {K}=1$). Our model of the phase evolution Ψ(f) accounts for the zeroth-order post-Newtonian point-particle contribution and for the resonant tidal excitation of individual g-modes. We ignore higher order post-Newtonian terms, spin, the equilibrium tide and non-linear tidal effects (such as those considered in Essick, Vitale & Weinberg 2016), and assume that the signal shuts off at the GW frequency corresponding to the innermost stable circular orbit f = 2fISCO ≃ 1.6 × 103 Hz [2.8 M⊙\/(M + M΄)] (Cutler & Flanagan 1994; Poisson & Will 1995). In Appendix B, we show that under these assumptions,\n(32)\r\n\\begin{equation}\r\n\\Psi (f) = \\Psi _{\\rm pp}(f) - \\sum _a\\left(1-\\frac{f}{f_a}\\right) \\delta \\phi _a \\Theta \\left(f-f_a\\right),\r\n\\end{equation}\r\nwhere, by the stationary-phase approximation, the point-particle phase is (Cutler & Flanagan 1994)\n(33)\r\n\\begin{equation}\r\n\\Psi _{\\rm pp}(f) = 2\\pi f t_{\\rm c} -\\phi _{\\rm c}-\\frac{\\pi }{4} +\\frac{3}{4}\\left(\\frac{8\\pi G\\mathcal {M}f}{c^3}\\right)^{-5\/3},\r\n\\end{equation}\r\nδϕa is the phase shift due to the tidal resonance with a mode a with eigenfrequency fa, and Θ(f − fa) is the Heaviside step function. Here tc and ϕc are constants of integration that set a reference time and phase. The duration of each resonance is, in general, much shorter than the orbital decay time-scale due to radiation reaction (their ratio is ${\\simeq } 0.1\\times [(\\mathcal {M}\/1.2\\,\\mathrm{M}_{\\odot })(f\/500 \\text{ Hz})]^{5\/6}$; see Lai 1994; Balachandran & Flanagan 2007; Flanagan & Racine 2007). We therefore model the resonance as an instantaneous process, which should be a good approximation since nearly all the g-modes we consider have $f_a^{\\rm (GR)} < 500\\,{\\rm Hz}$ (the one exception is the na = 1 hyperonic g-mode of the 1.6 M⊙ HS model which has $f_a^{\\rm (GR)}=740\\,{\\rm Hz}$).","Citation Text":["Balachandran & Flanagan (2007)"],"Citation Start End":[[11,41]]} {"Identifier":"2017MNRAS.470..350YBalachandran_&_Flanagan_2007_Instance_2","Paragraph":"Similar to Balachandran & Flanagan (2007), who also studied the detectability of mode resonances (see also Flanagan & Racine 2007), we assume that the frequency-domain GW signal has the form\n(30)\r\n\\begin{equation}\r\n\\tilde{h}(f) = \\mathcal {A} f^{-7\/6} \\text{e}^{\\text{i}\\Psi (f)},\r\n\\end{equation}\r\nwhere the amplitude (Maggiore 2007)\n(31)\r\n\\begin{equation}\r\n\\mathcal {A}=\\left(\\frac{5}{24\\pi ^{4\/3}}\\right)^{1\/2}\\left(\\frac{G\\mathcal {M}}{c^3}\\right)^{-5\/6}\\frac{\\mathcal {K}}{d}.\r\n\\end{equation}\r\nHere $\\mathcal {M}=[(M M^{\\prime })^{3}\/(M+M^{\\prime })]^{1\/5}$ is the chirp mass, d is the distance to the source and $\\mathcal {K}$ is the antenna response (for an optimally oriented source $\\mathcal {K}=1$). Our model of the phase evolution Ψ(f) accounts for the zeroth-order post-Newtonian point-particle contribution and for the resonant tidal excitation of individual g-modes. We ignore higher order post-Newtonian terms, spin, the equilibrium tide and non-linear tidal effects (such as those considered in Essick, Vitale & Weinberg 2016), and assume that the signal shuts off at the GW frequency corresponding to the innermost stable circular orbit f = 2fISCO ≃ 1.6 × 103 Hz [2.8 M⊙\/(M + M΄)] (Cutler & Flanagan 1994; Poisson & Will 1995). In Appendix B, we show that under these assumptions,\n(32)\r\n\\begin{equation}\r\n\\Psi (f) = \\Psi _{\\rm pp}(f) - \\sum _a\\left(1-\\frac{f}{f_a}\\right) \\delta \\phi _a \\Theta \\left(f-f_a\\right),\r\n\\end{equation}\r\nwhere, by the stationary-phase approximation, the point-particle phase is (Cutler & Flanagan 1994)\n(33)\r\n\\begin{equation}\r\n\\Psi _{\\rm pp}(f) = 2\\pi f t_{\\rm c} -\\phi _{\\rm c}-\\frac{\\pi }{4} +\\frac{3}{4}\\left(\\frac{8\\pi G\\mathcal {M}f}{c^3}\\right)^{-5\/3},\r\n\\end{equation}\r\nδϕa is the phase shift due to the tidal resonance with a mode a with eigenfrequency fa, and Θ(f − fa) is the Heaviside step function. Here tc and ϕc are constants of integration that set a reference time and phase. The duration of each resonance is, in general, much shorter than the orbital decay time-scale due to radiation reaction (their ratio is ${\\simeq } 0.1\\times [(\\mathcal {M}\/1.2\\,\\mathrm{M}_{\\odot })(f\/500 \\text{ Hz})]^{5\/6}$; see Lai 1994; Balachandran & Flanagan 2007; Flanagan & Racine 2007). We therefore model the resonance as an instantaneous process, which should be a good approximation since nearly all the g-modes we consider have $f_a^{\\rm (GR)} < 500\\,{\\rm Hz}$ (the one exception is the na = 1 hyperonic g-mode of the 1.6 M⊙ HS model which has $f_a^{\\rm (GR)}=740\\,{\\rm Hz}$).","Citation Text":["Balachandran & Flanagan 2007"],"Citation Start End":[[2174,2202]]} {"Identifier":"2016ApJ...825...41V__Nakajima_&_Ouchi_2014_Instance_1","Paragraph":"An LyC candidate at z = 3.212 in the GOODS-Southern field, named Ion2 (GDS-ID 033203.24-274518.8), was first identified by Vanzella et al. (2015). This candidate is a \n\n\n\n\n\n galaxy with SFR \n\n\n\n\n\n (sSFR\n\n\n\n\n\n), EW(Lyα)\n\n\n\n\n\n Å, and EW(\n\n\n\n\n\n)\n\n\n\n\n\n Å (de Barros et al. 2016). The compact star-forming region, showing strong [O iii]λλ4959,5007 emission lines (with a rest-frame equivalent width of 1500 Å) and a large Oxygen ratio \n\n\n\n\n\n\/\n\n\n\n\n\n (\n\n\n\n\n\n at 1σ, de Barros et al. 2016) measured with Keck\/MOSFIRE, makes Ion2 the highest redshift “Green Pea” galaxy the currently known and, accordingly to the photoionization models (Jaskot & Oey 2013; Nakajima & Ouchi 2014), an ideal candidate LyC emitter. A plausible spectroscopic LyC detection was subsequently discussed in de Barros et al. (2016). However, the presence of a close companion not resolved with ground-based spectroscopy and imaging (02, see Figure 1) cast some doubts on the association of the observed flux with Ion2,and thus on the reliability of the LyC leakage. Thanks to the Lyβ and Lyγ detection in the Very Large Telescope (VLT)\/VIMOS Ion2 spectrum (see Figure 6 panel (A), or de Barros et al. 2016, Figure 2), the spectroscopic redshift of component A is unambiguously z = 3.2. The 4 hr exposure is not enough to detect such absorption features with a signal-to-noise ratio (S\/N) of \n\n\n\n\n\n (as observed here) for component B, which at these wavelengths is mag = 27.2 in the continuum.11\n\n11\nFrom ESO\/Exposure Time Calculator, an S\/N \n\n\n\n\n\n is expected at this magnitude, wavelength, and integration time. This would imply an S\/N \n\n\n\n\n\n if Lyβ and Lyγ absorption lines arise from component B.\n Therefore these features arise from component A at z = 3.2. The [O iii] emission is also mainly associated with component A because the K-band magnitude is dominated by the strong [O iii] lines and the K-band spatial emission is more prominent from A. This is shown in Figure 2 where the VLT\/HAWKI K-band image has been extracted from the HUGS survey (Fontana et al. 2014).","Citation Text":["Nakajima & Ouchi 2014"],"Citation Start End":[[648,669]]} {"Identifier":"2020ApJ...900L..26W__Glendenning_&_Weber_1992_Instance_1","Paragraph":"The observation of FRB 200428 suggests the FRBs are accompanied by XRBs. The energy ratio between radio burst and XRB is about \n\n\n\n\n\n. If this value is valid for FRB 121102, the X-ray energy release in one period for FRB 121102 is about\n17\n\n\n\n\n\nThe typical active timescale of magnetars is about 100 yr (Beloborodov & Li 2016). The total energy release of XRBs in the active phase is\n18\n\n\n\n\n\nwhere τ is the active timescale of the magnetar. For FRB 121102, \n\n\n\n\n\n is assumed. Compared to the rotational energy, the magnetic energy is the main reservoir responsible for powering FRBs. The magnetic energy of magnetar is\n19\n\n\n\n\n\nwhere \n\n\n\n\n\n G is the interior magnetic field strength, and R = 12 km is the magnetar radius. This value is smaller than the required XRB energy. The XRB energy is shared by the ultrarelativistic ejecta and the baryon shell with a subrelativistic velocity vw. It has been found that the kinetic energy of the baryon shell is comparable to the flare energy (Metzger et al. 2019; Margalit et al. 2020b). We assume that the baryon shell is subrelativistic with a typical velocity \n\n\n\n\n\n. Based on the above assumptions, the baryonic mass ejected by magnetar in the active time can be derived as\n20\n\n\n\n\n\nThis value is much larger than the typical mass (\n\n\n\n\n\n) of a magnetar outer crust (Gudmundsson et al. 1983; Glendenning & Weber 1992). According to the structure of magnetars, the core is mainly composed of superfluid. The ejected baryon matter of the magnetar is mainly provided by crust. The baryonic mass estimated in this model is larger than the typical mass of a magnetar outer crust, indicating that the outer crust of the magnetar cannot eject enough baryonic matter required by the model. In Figure 2, we show the constraints on MB using Equation (20). If the radiation efficiency \n\n\n\n\n\n from FRB 200428 is used, the required baryonic mass MB is always larger than \n\n\n\n\n\n for the whole parameter ranges as shown in the left panel of Figure 2. If τ = 100 yr is fixed, the same result is shown in the right panel of Figure 2. The outer crust of magnetars is not sufficient to provide such a large baryonic mass, which challenges the synchrotron maser shock model. Interestingly, if the inner crust is included, the total mass of crust is about 0.01 M⊙ (Chamel & Haensel 2008), which is larger than the required baryonic mass. Theoretically, the physical mechanism and the rate of the baryonic mass ejection are both uncertain. More investigations are required. We also use the bursts of FRB 121102 observed by FAST to estimate the required baryonic mass (Li et al. 2019). The observation of FAST provides the information on the lowest-energy bursts of FRB 121102 so far. In a 56.5 hr observation, 1121 bursts were observed. The total energy of these bursts is 3.14 \n\n\n\n\n\n erg.3\n\n3\nD. Li & P. Wang 2020, private communications.\n Therefore, the average energy release in one period is about \n\n\n\n\n\n erg. Using the same formulae as above, the baryon mass can be approximated as\n21\n\n\n\n\n\nwhich is similar to that derived from GBT observation.","Citation Text":["Glendenning & Weber 1992"],"Citation Start End":[[1336,1360]]} {"Identifier":"2020MNRAS.495.4638O__Binney_&_Tremaine_1987_Instance_1","Paragraph":"The intrinsic (edge-on) ellipticity (ϵint) has been estimated using the observed V\/σ and ϵ based on the theoretical prediction of intrinsic shape for varying inclination under the assumption of rotating oblate system (Binney 2005). Cappellari et al. (2007) has shown that intrinsic ellipticity correlates with the anisotropy parameter using early-type galaxies from the SAURON IFS survey (de Zeeuw et al. 2002). Cappellari et al. (2016) presented the relationship between the intrinsic and observed ellipticities:\n(14)$$\\begin{eqnarray*}\r\n\\epsilon = 1-\\sqrt{1+\\epsilon _{\\rm int} (\\epsilon _{\\rm int}-2) \\sin ^2 i}.\r\n\\end{eqnarray*}$$The observed V\/σ with an inclination i can be corrected to the intrinsic (V\/σ)int for an edge-on (i = 90°) view (Binney & Tremaine 1987):\n(15)$$\\begin{eqnarray*}\r\n\\left(\\frac{V}{\\sigma }\\right) = \\left(\\frac{V}{\\sigma }\\right)_{\\rm int} \\frac{\\sin i}{\\sqrt{1-\\delta \\cos ^2 i}},\r\n\\end{eqnarray*}$$where δ is an approximation to the anisotropy parameter β such as δ ≈ β = 0.7ϵint. For each component, we generated a grid with varying ϵint and i. Then, we calculated corresponding ϵ and V\/σ for each ϵint and i using equations (14) and (15). The ϵint has been derived from the grid which has the best matched ϵ and V\/σ to the observation. Note that V\/σ for the bulge and disk components are measured using Re, PA, and ϵ of each component in this section, whereas all kinematic measurements in the other sections except for this section and Fig. 13 used the structural parameters from galaxies. Measuring V\/σ at the effective radius of each component gives more galaxies with kinematics for both components: 664 and 633 are available for measuring bulge and disk components (respectively), and 468 galaxies have kinematics available for both components. On the other hand, the above method is not valid for slowly rotating bulges (e.g. below the green line in Fig. 13) because they are not oblate rotators. In that instance, we adopt ϵint = ϵ as our best estimate of the intrinsic ellipticity (although it is strictly a lower limit).","Citation Text":["Binney & Tremaine 1987"],"Citation Start End":[[747,769]]} {"Identifier":"2021ApJ...920..151H__Raymond_et_al._2010_Instance_1","Paragraph":"This section discusses the results of planet–planet scattering in systems with two giant planets in four simulation sets (Table 1). The statistics use only simulations with one surviving planet after the other planet is ejected via planet–planet scattering (23.26% of all simulations; see Table 1), which is around 5500 simulations in each set. In two-planet systems, the instability boundary is very narrow. If both planets survive, its very likely they have none or very little interactions, so it is not very interesting to study them for our purpose. Simulations with planet–star (2.71% of all simulations) or planet–planet collisions (73.61% of all simulations; see Table 1) are excluded from the statistics, as obliquity evolution for the collision of fluid bodies is beyond the scope of this work (see Li & Lai 2020; Li et al. 2020). Simulations with energy error \n\n\n\n\n∣\n\n\n\nδ\nE\n\n\nE\n\n\n\n∣\n\n\n greater than \n\n\n\n\n\n(\n\n\n10\n\n\n−\n4\n\n\n)\n\n\n are also excluded (0.36% of all simulations), which is an adequate threshold for multiplanet systems (Barnes & Quinn 2004; Raymond et al. 2010). A negligible fraction of systems (0.03% of all simulations) that do not experience planet destruction in 108 yr are also excluded. Figures 5 and 6 show the distribution of the surviving planet’s final spin orientation and obliquity for simulation sets 1–3. The spin inclination is measured relative to the z-axis, which is aligned with the inner planet’s initial spin and orbit normal. The final spin and obliquity distribution is quite broad compared with the orbital inclination distribution (Figure 7). Overall, the final spin and obliquity distributions (Table 3) are broader than the inclination distributions, with 19.51% planets’ obliquity beyond 40°, and 8.77% of the surviving planets are on retrograde obliquity (i.e., the rotation is in reversed direction relative to the orbit). The inclination distribution only has 0.12% planets beyond 40°. The rate of highly oblique planets (>40°) are 17.86%, 31.98%, and 10.43% in sets 1, 2, and 3. There are 5.07% surviving planets on retrograde obliquity in the base set, 21.46% in set 2, and 3.21% in set 3. The distribution of obliquity for set 3 is more clustered at lower regions compared to the other sets. From the rate of high and retrograde obliquity in set 2 (the inner planet ends up at 0.19 au after the outer planet is ejected), we may expect a high rate of highly oblique planets close to the central star, and some oblique planets farther out (Figures 5 and 6). A moderate peak in Figure 6 for close-in planets in sets 1 and 2 between obliquities 170°–180° implies that Venus-like obliquity is possible. The simulation results imply that planets closer to the star receive more torque from it and become more evolved in obliquity.","Citation Text":["Raymond et al. 2010"],"Citation Start End":[[1059,1078]]} {"Identifier":"2022ApJ...939...44R__Esteban_et_al._2022_Instance_1","Paragraph":"Recently, Esteban et al. (2022) examined the abundances in the Galaxy as measured from a number of sources, including H ii regions from Arellano-Córdova et al. (2020, 2021), with the goal of assessing the large abundance dispersion that De Cia et al. (2021) measure in Galactic neutral clouds. The direct abundances in the H ii regions are calculated using T\n\ne\n[N ii] in the low-ionization zone and T\n\ne\n[O iii] in the high-ionization zone, only applying the Esteban et al. (2009) T\n\ne\n–T\n\ne\n relation when one of these temperatures is missing. From the 42 Galactic regions, the dispersion about the O\/H gradient is ∼0.07 dex, which is similar to the dispersion in metallicity measured from B-type stars, classical Cepheids, and young clusters in the Galaxy (Esteban et al. 2022), and significantly less than the dispersion measured in the neutral clouds. Méndez-Delgado et al. (2022a) corroborate the low dispersion in the Arellano-Córdova et al. (2020, 2021) H ii regions when considering nonzero temperature fluctuations and updated H ii region positions. In the spiral galaxy M101, Kennicutt et al. (2003) determine the abundance gradient from 20 H ii regions, the majority of which have direct T\n\ne\n[O iii] and T\n\ne\n[S iii] measurements, and nine of which have direct T\n\ne\n[N ii]. Citing the tight correlation they observe between T\n\ne\n[O iii] and T\n\ne\n[S iii], Kennicutt et al. (2003) use an average of the direct T\n\ne\n[O iii] and the inferred T\n\ne\n[O iii] from T\n\ne\n[S iii] to obtain the high-ionization zone temperature, and they use the direct T\n\ne\n[N ii] in the low-ionization zone, when available. Although this sample consists of only 20 regions, there is a clear abundance gradient in M101 with very little dispersion about the gradient. The dispersion reported by CHAOS (0.097 dex; Rogers et al. 2021) is slightly larger than the gradient from Kennicutt et al. (2003) would indicate, but this could be due to the inclusion of H ii regions with a single direct T\n\ne\n.","Citation Text":["Esteban et al. (2022)"],"Citation Start End":[[10,31]]} {"Identifier":"2022ApJ...939...44R__Esteban_et_al._2022_Instance_2","Paragraph":"Recently, Esteban et al. (2022) examined the abundances in the Galaxy as measured from a number of sources, including H ii regions from Arellano-Córdova et al. (2020, 2021), with the goal of assessing the large abundance dispersion that De Cia et al. (2021) measure in Galactic neutral clouds. The direct abundances in the H ii regions are calculated using T\n\ne\n[N ii] in the low-ionization zone and T\n\ne\n[O iii] in the high-ionization zone, only applying the Esteban et al. (2009) T\n\ne\n–T\n\ne\n relation when one of these temperatures is missing. From the 42 Galactic regions, the dispersion about the O\/H gradient is ∼0.07 dex, which is similar to the dispersion in metallicity measured from B-type stars, classical Cepheids, and young clusters in the Galaxy (Esteban et al. 2022), and significantly less than the dispersion measured in the neutral clouds. Méndez-Delgado et al. (2022a) corroborate the low dispersion in the Arellano-Córdova et al. (2020, 2021) H ii regions when considering nonzero temperature fluctuations and updated H ii region positions. In the spiral galaxy M101, Kennicutt et al. (2003) determine the abundance gradient from 20 H ii regions, the majority of which have direct T\n\ne\n[O iii] and T\n\ne\n[S iii] measurements, and nine of which have direct T\n\ne\n[N ii]. Citing the tight correlation they observe between T\n\ne\n[O iii] and T\n\ne\n[S iii], Kennicutt et al. (2003) use an average of the direct T\n\ne\n[O iii] and the inferred T\n\ne\n[O iii] from T\n\ne\n[S iii] to obtain the high-ionization zone temperature, and they use the direct T\n\ne\n[N ii] in the low-ionization zone, when available. Although this sample consists of only 20 regions, there is a clear abundance gradient in M101 with very little dispersion about the gradient. The dispersion reported by CHAOS (0.097 dex; Rogers et al. 2021) is slightly larger than the gradient from Kennicutt et al. (2003) would indicate, but this could be due to the inclusion of H ii regions with a single direct T\n\ne\n.","Citation Text":["Esteban et al. 2022"],"Citation Start End":[[762,781]]} {"Identifier":"2017ApJ...837...97L__Wang_et_al._2015_Instance_1","Paragraph":"The newly discovered arcs and new spectroscopic redshifts have been incorporated into updated HFF+ versions of the Abell 2744 and MACSJ0416.1-2403 lensing models (Table 5); many of these have \n\n\n\n\n\n (see Figure 8 for a comparison of the arc redshift distributions adopted by the pre-HFF and new HFF+ lensing models; Cypriano et al. 2004; Okabe & Umetsu 2008; Zitrin et al. 2009; 2013; Okabe et al. 2010a, 2010b; Merten et al. 2011; Christensen et al. 2012; Mann & Ebeling 2012; Jauzac et al. 2014; Lam et al. 2014; Richard et al. 2014; Balestra et al. 2015; Diego et al. 2015; Grillo et al. 2015; Jauzac et al. 2015; Rodney et al. 2015; Wang et al. 2015; Kawamata et al. 2016). The incorporation of these new multiple image systems often results in a reduction in the statistical uncertainty in the galaxy magnifications for a given model. All of the public HFF lensing models provide a range of possible realizations from which the statistical uncertainty of a given model set may be calculated (typically 100 but no fewer than 30). We plot the cumulative distribution of the galaxy magnification uncertainties σ(model)\/\n\n\n\n\n\n, for the galaxies and photometric redshifts provided by the ASTRODEEP catalogs (Merlin et al. 2016; Castellano et al. 2016a) for Abell 2744 (Figure 9) and MACSJ0416.1-2403 (Figure 10). Generally, the statistical uncertainties are reduced for the models computed with the new HFF data sets, with more dramatic reductions for the methods that rely strongly upon the strong-lensing constraints. The parametric methods (CATS, Sharon, Zitrin, GLAFIC) report median statistical magnification errors of 0.2%–5%, while the non-parametric methods (Bradac Williams, Diego) report median statistical magnification errors of 2%–11% for the post-HFF calculations (green curves), versus 2%–22% and 2%–17% respectively for pre-HFF models (blue curves). (We note that the statistical errors for the MACSJ0416.1-2403 Bradac post-HFF models (Hoag et al. 2016) included additional uncertainties due to the photometric redshift uncertainties of the multiple images. These were not included in the pre-HFF Bradac model, and thus may explain why the post-HFF statistical errors are larger for this model.)","Citation Text":["Wang et al. 2015"],"Citation Start End":[[637,653]]} {"Identifier":"2016ApJ...817..159K__Schlickeiser_&_Felten_2013_Instance_1","Paragraph":"As an illustrative example we apply the general results obtained in the last section to the IGM shortly after the reionization onset at a redshift of about z = 10. To this end we calculate the effective growth rate of a Maxwell–tensor distributed electron–proton plasma with a kinetic temperature of \n\n\n\n\n\n for both particle species and an electron density of \n\n\n\n\n\n being traversed by a highly relativistic beam with a Lorentz factor of \n\n\n\n\n\n. The corresponding fluctuations of the background plasma are dominated by a recently discovered damped, aperiodic mode \n\n\n\n\n\n with \n\n\n\n\n\n (Felten et al. 2013). Schlickeiser & Felten (2013) found that its quantitative description can be simplified by introducing the dimensionless wavenumber κ and the dimensionless frequency y defined by\n79\n\n\n\n\n\n\n\n80\n\n\n\n\n\nwhere kc is the inverse of the electron skin depth\n81\n\n\n\n\n\nmodified in such a way that it absorbs all remaining prefactors that occur in the dispersion relation:\n82\n\n\n\n\n\nHere, \n\n\n\n\n\n denotes the thermal velocity of the electrons. In terms of these variables the dispersion relation takes a simple form and is given by (Schlickeiser & Felten 2013)\n83\n\n\n\n\n\nwith\n84\n\n\n\n\n\nFor our present purposes it is more convenient to consider the frequency y as the independent variable rather than the wavenumber κ. This approach can easily be reversed by the approximation for the inverse dispersion relation derived by Schlickeiser & Felten (2013),\n85\n\n\n\n\n\n(This procedure was also carried out during the creation of Figures 1 and 3 shown below.) Our task is to compute the effective growth rate (78), which for aperiodic modes reads\n86\n\n\n\n\n\nMaking use of definitions (79)–(80) and the dispersion relation (83) we can rewrite this as\n87\n\n\n\n\n\nwhere we introduced the abbreviations\n88\n\n\n\n\n\n\n\n89\n\n\n\n\n\n\n\n90\n\n\n\n\n\nNext, we will turn to the transversal dispersion function of the unperturbed thermal background plasma (Schlickeiser & Felten 2013)\n91\n\n\n\n\n\nMaking use of (79)–(80) and (83) once more we can write the derivative as a function of y alone:\n92\n\n\n\n\n\nPlugging this expression into Equation (87) we arrive at the effective growth rate\n93\n\n\n\n\n\nwhere\n94\n\n\n\n\n\nNote that to zeroth order in ε this result reproduces the dispersion relation (83) of the unperturbed growth rate, and that it contains an additional first order correction term that accounts for the presence of the beam.","Citation Text":["Schlickeiser & Felten (2013)"],"Citation Start End":[[605,633]]} {"Identifier":"2016ApJ...817..159K__Schlickeiser_&_Felten_2013_Instance_2","Paragraph":"As an illustrative example we apply the general results obtained in the last section to the IGM shortly after the reionization onset at a redshift of about z = 10. To this end we calculate the effective growth rate of a Maxwell–tensor distributed electron–proton plasma with a kinetic temperature of \n\n\n\n\n\n for both particle species and an electron density of \n\n\n\n\n\n being traversed by a highly relativistic beam with a Lorentz factor of \n\n\n\n\n\n. The corresponding fluctuations of the background plasma are dominated by a recently discovered damped, aperiodic mode \n\n\n\n\n\n with \n\n\n\n\n\n (Felten et al. 2013). Schlickeiser & Felten (2013) found that its quantitative description can be simplified by introducing the dimensionless wavenumber κ and the dimensionless frequency y defined by\n79\n\n\n\n\n\n\n\n80\n\n\n\n\n\nwhere kc is the inverse of the electron skin depth\n81\n\n\n\n\n\nmodified in such a way that it absorbs all remaining prefactors that occur in the dispersion relation:\n82\n\n\n\n\n\nHere, \n\n\n\n\n\n denotes the thermal velocity of the electrons. In terms of these variables the dispersion relation takes a simple form and is given by (Schlickeiser & Felten 2013)\n83\n\n\n\n\n\nwith\n84\n\n\n\n\n\nFor our present purposes it is more convenient to consider the frequency y as the independent variable rather than the wavenumber κ. This approach can easily be reversed by the approximation for the inverse dispersion relation derived by Schlickeiser & Felten (2013),\n85\n\n\n\n\n\n(This procedure was also carried out during the creation of Figures 1 and 3 shown below.) Our task is to compute the effective growth rate (78), which for aperiodic modes reads\n86\n\n\n\n\n\nMaking use of definitions (79)–(80) and the dispersion relation (83) we can rewrite this as\n87\n\n\n\n\n\nwhere we introduced the abbreviations\n88\n\n\n\n\n\n\n\n89\n\n\n\n\n\n\n\n90\n\n\n\n\n\nNext, we will turn to the transversal dispersion function of the unperturbed thermal background plasma (Schlickeiser & Felten 2013)\n91\n\n\n\n\n\nMaking use of (79)–(80) and (83) once more we can write the derivative as a function of y alone:\n92\n\n\n\n\n\nPlugging this expression into Equation (87) we arrive at the effective growth rate\n93\n\n\n\n\n\nwhere\n94\n\n\n\n\n\nNote that to zeroth order in ε this result reproduces the dispersion relation (83) of the unperturbed growth rate, and that it contains an additional first order correction term that accounts for the presence of the beam.","Citation Text":["Schlickeiser & Felten 2013"],"Citation Start End":[[1120,1146]]} {"Identifier":"2016ApJ...817..159K__Schlickeiser_&_Felten_2013_Instance_3","Paragraph":"As an illustrative example we apply the general results obtained in the last section to the IGM shortly after the reionization onset at a redshift of about z = 10. To this end we calculate the effective growth rate of a Maxwell–tensor distributed electron–proton plasma with a kinetic temperature of \n\n\n\n\n\n for both particle species and an electron density of \n\n\n\n\n\n being traversed by a highly relativistic beam with a Lorentz factor of \n\n\n\n\n\n. The corresponding fluctuations of the background plasma are dominated by a recently discovered damped, aperiodic mode \n\n\n\n\n\n with \n\n\n\n\n\n (Felten et al. 2013). Schlickeiser & Felten (2013) found that its quantitative description can be simplified by introducing the dimensionless wavenumber κ and the dimensionless frequency y defined by\n79\n\n\n\n\n\n\n\n80\n\n\n\n\n\nwhere kc is the inverse of the electron skin depth\n81\n\n\n\n\n\nmodified in such a way that it absorbs all remaining prefactors that occur in the dispersion relation:\n82\n\n\n\n\n\nHere, \n\n\n\n\n\n denotes the thermal velocity of the electrons. In terms of these variables the dispersion relation takes a simple form and is given by (Schlickeiser & Felten 2013)\n83\n\n\n\n\n\nwith\n84\n\n\n\n\n\nFor our present purposes it is more convenient to consider the frequency y as the independent variable rather than the wavenumber κ. This approach can easily be reversed by the approximation for the inverse dispersion relation derived by Schlickeiser & Felten (2013),\n85\n\n\n\n\n\n(This procedure was also carried out during the creation of Figures 1 and 3 shown below.) Our task is to compute the effective growth rate (78), which for aperiodic modes reads\n86\n\n\n\n\n\nMaking use of definitions (79)–(80) and the dispersion relation (83) we can rewrite this as\n87\n\n\n\n\n\nwhere we introduced the abbreviations\n88\n\n\n\n\n\n\n\n89\n\n\n\n\n\n\n\n90\n\n\n\n\n\nNext, we will turn to the transversal dispersion function of the unperturbed thermal background plasma (Schlickeiser & Felten 2013)\n91\n\n\n\n\n\nMaking use of (79)–(80) and (83) once more we can write the derivative as a function of y alone:\n92\n\n\n\n\n\nPlugging this expression into Equation (87) we arrive at the effective growth rate\n93\n\n\n\n\n\nwhere\n94\n\n\n\n\n\nNote that to zeroth order in ε this result reproduces the dispersion relation (83) of the unperturbed growth rate, and that it contains an additional first order correction term that accounts for the presence of the beam.","Citation Text":["Schlickeiser & Felten (2013)"],"Citation Start End":[[1407,1435]]} {"Identifier":"2016ApJ...817..159K__Schlickeiser_&_Felten_2013_Instance_4","Paragraph":"As an illustrative example we apply the general results obtained in the last section to the IGM shortly after the reionization onset at a redshift of about z = 10. To this end we calculate the effective growth rate of a Maxwell–tensor distributed electron–proton plasma with a kinetic temperature of \n\n\n\n\n\n for both particle species and an electron density of \n\n\n\n\n\n being traversed by a highly relativistic beam with a Lorentz factor of \n\n\n\n\n\n. The corresponding fluctuations of the background plasma are dominated by a recently discovered damped, aperiodic mode \n\n\n\n\n\n with \n\n\n\n\n\n (Felten et al. 2013). Schlickeiser & Felten (2013) found that its quantitative description can be simplified by introducing the dimensionless wavenumber κ and the dimensionless frequency y defined by\n79\n\n\n\n\n\n\n\n80\n\n\n\n\n\nwhere kc is the inverse of the electron skin depth\n81\n\n\n\n\n\nmodified in such a way that it absorbs all remaining prefactors that occur in the dispersion relation:\n82\n\n\n\n\n\nHere, \n\n\n\n\n\n denotes the thermal velocity of the electrons. In terms of these variables the dispersion relation takes a simple form and is given by (Schlickeiser & Felten 2013)\n83\n\n\n\n\n\nwith\n84\n\n\n\n\n\nFor our present purposes it is more convenient to consider the frequency y as the independent variable rather than the wavenumber κ. This approach can easily be reversed by the approximation for the inverse dispersion relation derived by Schlickeiser & Felten (2013),\n85\n\n\n\n\n\n(This procedure was also carried out during the creation of Figures 1 and 3 shown below.) Our task is to compute the effective growth rate (78), which for aperiodic modes reads\n86\n\n\n\n\n\nMaking use of definitions (79)–(80) and the dispersion relation (83) we can rewrite this as\n87\n\n\n\n\n\nwhere we introduced the abbreviations\n88\n\n\n\n\n\n\n\n89\n\n\n\n\n\n\n\n90\n\n\n\n\n\nNext, we will turn to the transversal dispersion function of the unperturbed thermal background plasma (Schlickeiser & Felten 2013)\n91\n\n\n\n\n\nMaking use of (79)–(80) and (83) once more we can write the derivative as a function of y alone:\n92\n\n\n\n\n\nPlugging this expression into Equation (87) we arrive at the effective growth rate\n93\n\n\n\n\n\nwhere\n94\n\n\n\n\n\nNote that to zeroth order in ε this result reproduces the dispersion relation (83) of the unperturbed growth rate, and that it contains an additional first order correction term that accounts for the presence of the beam.","Citation Text":["Schlickeiser & Felten 2013"],"Citation Start End":[[1900,1926]]} {"Identifier":"2021MNRAS.502.5038N__Scuflaire_&_Noels_1986_Instance_1","Paragraph":"Except for WR 134, the detected frequencies are high, from 3 d−1 up to 14 d−1. This cannot be easily reconciled with an orbital period (the companion would travel inside the WR star), nor a rotation rate (it would be above break-up velocity). Therefore, the most probable culprits are pulsations. WR 66 very probably possesses a close neighbour (see Section 2.1), which could cast doubt on the identification of the pulsating star, but that is not the case for the other stars (including WR 123: see Lefèvre et al. 2005). Pulsations here are thus considered to originate from the WR star itself, and such a possibility has actually been considered before. Pushed by the observational considerations of Vreux (1985), the first pulsation models for WRs were elaborated more than 30 years ago, with predicted periods of about one hour (Maeder 1985; Scuflaire & Noels 1986). Subsequent work by Glatzel et al. (1999) focused on strange modes in small and hot helium stars (often taken as behaving similarly to WRs) and the predicted pulsations had periods of several minutes with amplitudes of several mmag. After the discovery of a 2.45 d−1 signal in WR 123 (Lefèvre et al. 2005), i.e. at a much lower frequency than expected, the models were revisited. Strange modes were extended to stars with larger radii (Dorfi, Gautschy & Saio 2006; Glatzel 2008), while predictions of g-modes excited by the κ mechanism were made for WRs by Townsend & MacDonald (2006). In both cases, the predicted periods could be made compatible with the 10-h signal observed in WR 123. The signals we observe have frequencies in the same range, even for the 2-min cadence data, which allows us to probe very high frequencies, but no coherent signal is detected above 14 d−1: WRs thus seem to pulsate only at moderately high frequencies. Furthermore, Townsend & MacDonald (2006) expected pulsations with frequencies that are higher in early WN (2–8 d−1) than in late WN (1–2 d−1). For our pulsators, only WR 7 has an early WN type and its frequency values are not particularly higher: its main signals are in the same frequency range as those of the late-type WR 66. Moreover, the highest frequencies are all found in late WN stars. However, Townsend & MacDonald (2006) models were made for ‘general\/typical’ stars, not specific ones. In addition, since the WR light mostly comes from inside the wind, the filtering effect of the wind on a signal from the underlying hydrostatic surface needs to be assessed in detail. New, dedicated models will be needed for a more in-depth comparison between observations and predictions.","Citation Text":["Scuflaire & Noels 1986"],"Citation Start End":[[846,868]]} {"Identifier":"2021ApJ...915L..13H__Tilley_et_al._2004_Instance_3","Paragraph":"To obtain reaction rates in a wide temperature range \n\n\n\n\n\n\nT\n\n\n9\n\n\n=\n0.001\n\n\n–10 (where T9 is in units of 109 K) for BBN calculation inputs, continuous excitation functions over \n\n\n\n\n\n\n10\n\n\n−\n8\n\n\n\n\n to a few MeV are needed for numerical integration. Therefore we performed an R-matrix analysis to compile both the present and the previous data of these three reaction channels by using AZURE2 (Azuma et al. 2010) including all the relevant partial widths \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n. The 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n data set used for the R-matrix analysis is based on the same selection as used in Damone et al. (2018), Damone (2018; part of Dam18 + Sek76 as displayed in Figure 2), and the present THM data, Bor63, and Pop76 are added. For the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n and 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n channels, all the labeled data shown in Figure 2 (except for p1 Tom19 and \n\n\n\n\nγ\nα\n\n\n Bar16) were used without any data cutoff. Appendix B shows the adopted data sets more explicitly. We included nine known levels below the 8Be excitation energy of \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\nMeV\n\n\n (Tilley et al. 2004) and an additional nonresonant background pole, with a common channel radius of 5 fm for each channel in the same manner as Adahchour & Descouvemont (2003). The most significant channel 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n7\n\n\n\n\nLi is dominated by four of these levels as described in detail by a former R-matrix study (Adahchour & Descouvemont 2003; Descouvemont et al. 2004); the 2− resonance near the neutron threshold (labeled as level I) principally dominates the cross section up to the BBN energies, the two 3+ states at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.24\n\nMeV\n\n\n (level II) and \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n21.5\n\nMeV\n\n\n well characterize the corresponding single peaks, and a 2+ background pole accounts for the enhancement at high energies. The most important resonances to expand analysis to the 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n7\n\n\n\n\nLi* and 7Be\n\n\n\n\n\n\n(\nn\n,\nα\n)\n\n\n4\n\n\n\n\nHe channels are the 1− state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.4\n\nMeV\n\n\n (level III) and the 2+ state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.1\n\nMeV\n\n\n (level IV), respectively; the former expresses the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n resonance behavior peaked at \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n0.5\n\nMeV\n\n\n tailing down to the thermal neutron energy by the \n\n\n\n\n1\n\n\/\n\nv\n\n\n law, and the latter forms the first peak in the 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n spectrum around \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n1\n\nMeV\n\n\n. Despite its importance in the \n\n\n\n\n(\nn\n,\nα\n)\n\n\n channel, level IV is much less significant in the total cross section especially at lower energies due to its p-wave nature. Therefore we imposed some restrictions on level IV, which made the analysis much simpler; fixing \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n at a known ratio \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\/\n\n\n\nΓ\n\n\np\n\n\n∼\n4.5\n\n\n (Tilley et al. 2004), and freeing \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n and resonance energy (refitted to be 19.87 MeV) not to significantly exceed the known total width \n\n\n\n\nΓ\n=\n880\n\n\nkeV\n\n\n (Tilley et al. 2004). The other four higher-lying levels (0+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.2\n\nMeV\n\n\n, 2+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22.24\n\nMeV\n\n\n, 1− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22\n\n\n MeV, and 2− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\n\n MeV) play rather supplementary roles mainly for the higher-energy behavior. The 4+ and 4− higher-spin states (at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.86\n\nMeV\n\n\n and 20.9 MeV, respectively) were not included due to their limited influences. We do not introduce the γ-emission channels to fit the Bar16 plots (representing the 7Be\n\n\n\n\n\n\n\n\nn\n,\nγ\nα\n\n\n\n\n4\n\n\n\n\nHe reaction channel Barbagallo et al. 2016), which appears significant only below the BBN energies. See Appendix C for more details on the present R-matrix analysis.","Citation Text":["Tilley et al. 2004"],"Citation Start End":[[3015,3033]]} {"Identifier":"2021ApJ...915L..13H__Tilley_et_al._2004_Instance_2","Paragraph":"To obtain reaction rates in a wide temperature range \n\n\n\n\n\n\nT\n\n\n9\n\n\n=\n0.001\n\n\n–10 (where T9 is in units of 109 K) for BBN calculation inputs, continuous excitation functions over \n\n\n\n\n\n\n10\n\n\n−\n8\n\n\n\n\n to a few MeV are needed for numerical integration. Therefore we performed an R-matrix analysis to compile both the present and the previous data of these three reaction channels by using AZURE2 (Azuma et al. 2010) including all the relevant partial widths \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n. The 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n data set used for the R-matrix analysis is based on the same selection as used in Damone et al. (2018), Damone (2018; part of Dam18 + Sek76 as displayed in Figure 2), and the present THM data, Bor63, and Pop76 are added. For the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n and 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n channels, all the labeled data shown in Figure 2 (except for p1 Tom19 and \n\n\n\n\nγ\nα\n\n\n Bar16) were used without any data cutoff. Appendix B shows the adopted data sets more explicitly. We included nine known levels below the 8Be excitation energy of \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\nMeV\n\n\n (Tilley et al. 2004) and an additional nonresonant background pole, with a common channel radius of 5 fm for each channel in the same manner as Adahchour & Descouvemont (2003). The most significant channel 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n7\n\n\n\n\nLi is dominated by four of these levels as described in detail by a former R-matrix study (Adahchour & Descouvemont 2003; Descouvemont et al. 2004); the 2− resonance near the neutron threshold (labeled as level I) principally dominates the cross section up to the BBN energies, the two 3+ states at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.24\n\nMeV\n\n\n (level II) and \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n21.5\n\nMeV\n\n\n well characterize the corresponding single peaks, and a 2+ background pole accounts for the enhancement at high energies. The most important resonances to expand analysis to the 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n7\n\n\n\n\nLi* and 7Be\n\n\n\n\n\n\n(\nn\n,\nα\n)\n\n\n4\n\n\n\n\nHe channels are the 1− state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.4\n\nMeV\n\n\n (level III) and the 2+ state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.1\n\nMeV\n\n\n (level IV), respectively; the former expresses the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n resonance behavior peaked at \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n0.5\n\nMeV\n\n\n tailing down to the thermal neutron energy by the \n\n\n\n\n1\n\n\/\n\nv\n\n\n law, and the latter forms the first peak in the 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n spectrum around \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n1\n\nMeV\n\n\n. Despite its importance in the \n\n\n\n\n(\nn\n,\nα\n)\n\n\n channel, level IV is much less significant in the total cross section especially at lower energies due to its p-wave nature. Therefore we imposed some restrictions on level IV, which made the analysis much simpler; fixing \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n at a known ratio \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\/\n\n\n\nΓ\n\n\np\n\n\n∼\n4.5\n\n\n (Tilley et al. 2004), and freeing \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n and resonance energy (refitted to be 19.87 MeV) not to significantly exceed the known total width \n\n\n\n\nΓ\n=\n880\n\n\nkeV\n\n\n (Tilley et al. 2004). The other four higher-lying levels (0+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.2\n\nMeV\n\n\n, 2+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22.24\n\nMeV\n\n\n, 1− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22\n\n\n MeV, and 2− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\n\n MeV) play rather supplementary roles mainly for the higher-energy behavior. The 4+ and 4− higher-spin states (at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.86\n\nMeV\n\n\n and 20.9 MeV, respectively) were not included due to their limited influences. We do not introduce the γ-emission channels to fit the Bar16 plots (representing the 7Be\n\n\n\n\n\n\n\n\nn\n,\nγ\nα\n\n\n\n\n4\n\n\n\n\nHe reaction channel Barbagallo et al. 2016), which appears significant only below the BBN energies. See Appendix C for more details on the present R-matrix analysis.","Citation Text":["Tilley et al. 2004"],"Citation Start End":[[2843,2861]]} {"Identifier":"2021ApJ...915L..13H__Tilley_et_al._2004_Instance_1","Paragraph":"To obtain reaction rates in a wide temperature range \n\n\n\n\n\n\nT\n\n\n9\n\n\n=\n0.001\n\n\n–10 (where T9 is in units of 109 K) for BBN calculation inputs, continuous excitation functions over \n\n\n\n\n\n\n10\n\n\n−\n8\n\n\n\n\n to a few MeV are needed for numerical integration. Therefore we performed an R-matrix analysis to compile both the present and the previous data of these three reaction channels by using AZURE2 (Azuma et al. 2010) including all the relevant partial widths \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n. The 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n data set used for the R-matrix analysis is based on the same selection as used in Damone et al. (2018), Damone (2018; part of Dam18 + Sek76 as displayed in Figure 2), and the present THM data, Bor63, and Pop76 are added. For the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n and 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n channels, all the labeled data shown in Figure 2 (except for p1 Tom19 and \n\n\n\n\nγ\nα\n\n\n Bar16) were used without any data cutoff. Appendix B shows the adopted data sets more explicitly. We included nine known levels below the 8Be excitation energy of \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\nMeV\n\n\n (Tilley et al. 2004) and an additional nonresonant background pole, with a common channel radius of 5 fm for each channel in the same manner as Adahchour & Descouvemont (2003). The most significant channel 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n7\n\n\n\n\nLi is dominated by four of these levels as described in detail by a former R-matrix study (Adahchour & Descouvemont 2003; Descouvemont et al. 2004); the 2− resonance near the neutron threshold (labeled as level I) principally dominates the cross section up to the BBN energies, the two 3+ states at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.24\n\nMeV\n\n\n (level II) and \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n21.5\n\nMeV\n\n\n well characterize the corresponding single peaks, and a 2+ background pole accounts for the enhancement at high energies. The most important resonances to expand analysis to the 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n7\n\n\n\n\nLi* and 7Be\n\n\n\n\n\n\n(\nn\n,\nα\n)\n\n\n4\n\n\n\n\nHe channels are the 1− state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.4\n\nMeV\n\n\n (level III) and the 2+ state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.1\n\nMeV\n\n\n (level IV), respectively; the former expresses the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n resonance behavior peaked at \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n0.5\n\nMeV\n\n\n tailing down to the thermal neutron energy by the \n\n\n\n\n1\n\n\/\n\nv\n\n\n law, and the latter forms the first peak in the 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n spectrum around \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n1\n\nMeV\n\n\n. Despite its importance in the \n\n\n\n\n(\nn\n,\nα\n)\n\n\n channel, level IV is much less significant in the total cross section especially at lower energies due to its p-wave nature. Therefore we imposed some restrictions on level IV, which made the analysis much simpler; fixing \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n at a known ratio \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\/\n\n\n\nΓ\n\n\np\n\n\n∼\n4.5\n\n\n (Tilley et al. 2004), and freeing \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n and resonance energy (refitted to be 19.87 MeV) not to significantly exceed the known total width \n\n\n\n\nΓ\n=\n880\n\n\nkeV\n\n\n (Tilley et al. 2004). The other four higher-lying levels (0+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.2\n\nMeV\n\n\n, 2+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22.24\n\nMeV\n\n\n, 1− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22\n\n\n MeV, and 2− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\n\n MeV) play rather supplementary roles mainly for the higher-energy behavior. The 4+ and 4− higher-spin states (at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.86\n\nMeV\n\n\n and 20.9 MeV, respectively) were not included due to their limited influences. We do not introduce the γ-emission channels to fit the Bar16 plots (representing the 7Be\n\n\n\n\n\n\n\n\nn\n,\nγ\nα\n\n\n\n\n4\n\n\n\n\nHe reaction channel Barbagallo et al. 2016), which appears significant only below the BBN energies. See Appendix C for more details on the present R-matrix analysis.","Citation Text":["Tilley et al. 2004"],"Citation Start End":[[1134,1152]]} {"Identifier":"2016MNRAS.459.3585G__Lloyd_2003_Instance_1","Paragraph":"We first consider the case in which the star is surrounded by a gaseous atmosphere. The star surface is divided in six angular patches in magnetic colatitude, centred at the values θ = {0°, 10°, 30°, 50°, 70°, 89°}. By using the magnetic and temperature profiles previously described we compute, for each θ, the local magnetic field strength, B, the angle θB between the magnetic field and the normal to the surface, and hence the temperature, T. We then compute a set of atmospheric models corresponding to the six θ angles. Since the models are computed using different integration grids in the photon phase space (because the choice of the photon trajectories along which the radiative transfer is solved needs to be optimized to ensure fast convergence at the different values of magnetic field strength and inclination, see Lloyd 2003), we reinterpolate all model outputs over a common grid. This results in three 4D arrays for the emergent intensity $I^i_\\nu (\\boldsymbol k,\\theta ) \\equiv I^i(E,\\mu _k,\\phi _k,\\theta )$ (i = 1, …, 3) which contain the total intensity and the intensities for the ordinary and extraordinary modes, respectively. In order to take into account the emission from the southern magnetic hemisphere of the star, we use the previous 4D arrays with the substitutions θB → π − θB and ϕk → π − ϕk, which is justified by the symmetry properties of the opacities. By using the ray tracing method described in Section 2, we can then compute light curves, phase resolved spectra and polarization fractions for each choice of the angles χ and ξ. As an example, Fig. 3 shows the X-ray light curve (0.12–0.39 keV) and the phase-dependent polarization degree in the X-ray and optical7 (B-filter) bands, for χ = 90° and ξ = 15°. For this particular viewing geometry, the X-ray pulsed fraction is 1 per cent, in agreement with the observed data and, as illustrated in the figure, the polarization degree is expected to be substantial and constant in phase.","Citation Text":["Lloyd 2003"],"Citation Start End":[[829,839]]} {"Identifier":"2015ApJ...799..140S__Kubota_&_Makishima_2004_Instance_1","Paragraph":"However, this approximation holds only for luminosities ≲ 0.3LEdd. At higher accretion rates, the hardening factor κ increases with luminosity and can be as high as ≈2.5–3 for some Galactic BHs (e.g., GRO J1655−40 at outburst peak, and GRS 1915+105) and for ULXs in the slim-disk state (Watarai & Mineshige 2003; Kawaguchi 2003; Shrader & Titarchuk 2003; Isobe et al. 2012). This is why at near-Eddington luminosities, the fitted color temperature Tin increases faster than the standard high\/soft state relation (“anomalous regime”; Kubota & Makishima 2004; Abe et al. 2005). Given the luminosities of M83 ULX-1 in the three XMM-Newton epochs, and the fact that a disk model with p ≈ 0.6 provides the best fit to the data, we argue that the source was likely to be in the anomalous regime (slightly below Eddington) or in the slim disk regime (slightly above Eddington), and, therefore, we take a hardening factor κ ≈ 3 for BH mass estimates. Following Vierdayanti et al. (2008), we also take ξ ≈ 0.353, which takes into account the transonic flow in the pseudo-Newtonian potential. Taking an average normalization constant Ndisk = (2.5 ± 0.5) × 10−3 from our diskpbb fit (Table 2), we obtain a “true” inner disk radius Rin ≈ (73 ± 15)(cos θ)−1\/2 km. This corresponds to an “apparent” BH mass\n2Finally, we need to take into account that the inner radius of a slim disk extends slightly inside the innermost stable circular orbit, so that the true mass is MBH ≈ 1.2MX (Vierdayanti et al. 2008). This gives our final best estimate of the BH mass as\n3In principle, the estimated mass can be as high as ≈60 M in the (implausible) extreme Kerr scenario; however, the fact that the system appears to be in the anomalous regime (upper end of the high\/soft state) or in the slim disk state for a moderate bolometric luminosity ≈2 × 1039 erg s−1 (and possibly even lower, considering the 2014 January spectrum) suggests that the BH mass is closer to ∼10–20 M. The same argument holds if we interpret the X-ray spectra as Comptonized emission from a warm, optically thick corona, which is typical of sources at LX ≈ 1–3LEdd (Gladstone et al. 2009).","Citation Text":["Kubota & Makishima 2004"],"Citation Start End":[[547,570]]} {"Identifier":"2019MNRAS.487.3021A__Ali_et_al._2018a_Instance_1","Paragraph":"The ultraviolet (UV) upturn or excess is an unexpected rise in flux in the spectral energy distributions (SEDs) of early-type galaxies shortwards of 2500 Å. It appears to be a nearly ubiquitous property of spheroids and bulge-dominated galaxies (see e.g. Yi 2008, 2010 for a recent review), although their generally old, metal-rich, and quiescent stellar populations (e.g. Thomas et al. 2005, 2010) should contain no sources capable of providing significant flux below the 4000 Å break. While many candidates have been proposed, the source population is generally agreed to consist of hot horizontal branch (HB) stars (Greggio & Renzini 1990; Brown et al. 1998a) and it now appears most likely that this population is helium-rich and formed in situ at high redshift (Ali et al. 2018a,b,c). While such stars are now known to exist in globular clusters in our Galaxy (e.g. see Norris 2004; Piotto et al. 2005, 2007) and likely elsewhere (Kaviraj et al. 2007b; Mieske et al. 2008; Peacock et al. 2017), the origin of such high helium abundances is unclear.1 It has been suggested that the effect may depend on the environment: stratification of helium in the centres of clusters might create populations of galaxies with high helium abundances (Peng & Nagai 2009). On the other hand, it is also possible that the helium enrichment depends on the details of early star formation, as in globular clusters. Differences in the originating mechanisms or time-scales may be reflected in different evolutionary histories for galaxies in clusters and the field. Atlee, Assef & Kochanek (2009) find a slow decrease in the strength of the upturn for a sample of bright field elliptical galaxies at 0 z 0.65 compared to the nearly constant colour for very bright ellipticals in the works of Brown et al. (1998b, 2000, 2003) and brightest cluster galaxies (Loubser & Sánchez-Blázquez 2011; Boissier et al. 2018). In our work on much larger samples of cluster early types with luminosities down to L*, we also see no evolution at z 0.55 (Ali et al. 2018a,b,c) but then detect a rapid reddening in the UV colour at z = 0.7; this may be consistent with the last data point in Atlee et al. (2009), despite the large errors and small number statistics. Le Cras et al. (2016) also find evidence for evolution in the UV upturn at z > 0.6, albeit from stacked spectra and using spectroscopic indices sensitive to the HB population, for a sample of very luminous BOSS galaxies (as opposed to the UV photometry used by other studies).","Citation Text":["Ali et al. 2018a"],"Citation Start End":[[767,783]]} {"Identifier":"2019MNRAS.487.3021A__Ali_et_al._2018a_Instance_2","Paragraph":"The ultraviolet (UV) upturn or excess is an unexpected rise in flux in the spectral energy distributions (SEDs) of early-type galaxies shortwards of 2500 Å. It appears to be a nearly ubiquitous property of spheroids and bulge-dominated galaxies (see e.g. Yi 2008, 2010 for a recent review), although their generally old, metal-rich, and quiescent stellar populations (e.g. Thomas et al. 2005, 2010) should contain no sources capable of providing significant flux below the 4000 Å break. While many candidates have been proposed, the source population is generally agreed to consist of hot horizontal branch (HB) stars (Greggio & Renzini 1990; Brown et al. 1998a) and it now appears most likely that this population is helium-rich and formed in situ at high redshift (Ali et al. 2018a,b,c). While such stars are now known to exist in globular clusters in our Galaxy (e.g. see Norris 2004; Piotto et al. 2005, 2007) and likely elsewhere (Kaviraj et al. 2007b; Mieske et al. 2008; Peacock et al. 2017), the origin of such high helium abundances is unclear.1 It has been suggested that the effect may depend on the environment: stratification of helium in the centres of clusters might create populations of galaxies with high helium abundances (Peng & Nagai 2009). On the other hand, it is also possible that the helium enrichment depends on the details of early star formation, as in globular clusters. Differences in the originating mechanisms or time-scales may be reflected in different evolutionary histories for galaxies in clusters and the field. Atlee, Assef & Kochanek (2009) find a slow decrease in the strength of the upturn for a sample of bright field elliptical galaxies at 0 z 0.65 compared to the nearly constant colour for very bright ellipticals in the works of Brown et al. (1998b, 2000, 2003) and brightest cluster galaxies (Loubser & Sánchez-Blázquez 2011; Boissier et al. 2018). In our work on much larger samples of cluster early types with luminosities down to L*, we also see no evolution at z 0.55 (Ali et al. 2018a,b,c) but then detect a rapid reddening in the UV colour at z = 0.7; this may be consistent with the last data point in Atlee et al. (2009), despite the large errors and small number statistics. Le Cras et al. (2016) also find evidence for evolution in the UV upturn at z > 0.6, albeit from stacked spectra and using spectroscopic indices sensitive to the HB population, for a sample of very luminous BOSS galaxies (as opposed to the UV photometry used by other studies).","Citation Text":["Ali et al. 2018a"],"Citation Start End":[[2025,2041]]} {"Identifier":"2018MNRAS.478..126G__Riess_et_al._2016_Instance_1","Paragraph":"It may be appropriate to single out at this point the recent and interesting works by Lin & Ishak (2017a,b) in which the authors run a so-called (dis)cordance test based on using a proposed index of inconsistency (IOI) tailored at finding possible inconsistencies\/tensions between two or more data sets in a systematic and efficient way. For instance, it is well known that there is a persistent discrepancy between the Planck CMB measurements of H0 and the local measurements based on distance ladder (Riess et al. 2016, 2018b). At the same time, if one compares what is inferred from Planck 2015 best-fitting values, the LSS\/RSD measurements generally assign smaller power to the LSS data parametrized in terms of the weighted linear growth rate f(z)σ8(z). This feature is of course nothing but the σ8-tension we have been addressing in this paper. It is therefore natural to run the IOI test for the different kinds of H0 measurements and also to study the consistency between the H0 and the growth data. For example, upon comparing the constraints on H0 from different methods, Lin & Ishak (2017b) observe a decrease of the IOI when the local H0 measurement is removed. From this fact they conclude that the local measurement of H0 is an outlier compared to the others, what would favour a systematics-based explanation. This situation is compatible with the observed improvement in the statistical quality of the fitting analysis by Solà, Gómez-Valent & de Cruz Pérez (2017b,c) when the local H0 measurement is removed from the overall fit of the data using the RVM and the ΛCDM. In this respect, let us mention that a recent model-independent analysis of data on cosmic chronometers and an updated compilation of SNIa seem to favour the lower range of H0 (Gómez-Valent & Amendola 2018), what would be more along the line of the results found here, which favour a theoretical interpretation of the observed σ8 and H0 tensions in terms of vacuum dynamics and in general of DDE (cf. Fig. 10).","Citation Text":["Riess et al. 2016","Solà, Gómez-Valent & de Cruz Pérez (2017b"],"Citation Start End":[[503,520],[1438,1479]]} {"Identifier":"2018MNRAS.478..126GLin_&_Ishak_(2017b)_Instance_2","Paragraph":"It may be appropriate to single out at this point the recent and interesting works by Lin & Ishak (2017a,b) in which the authors run a so-called (dis)cordance test based on using a proposed index of inconsistency (IOI) tailored at finding possible inconsistencies\/tensions between two or more data sets in a systematic and efficient way. For instance, it is well known that there is a persistent discrepancy between the Planck CMB measurements of H0 and the local measurements based on distance ladder (Riess et al. 2016, 2018b). At the same time, if one compares what is inferred from Planck 2015 best-fitting values, the LSS\/RSD measurements generally assign smaller power to the LSS data parametrized in terms of the weighted linear growth rate f(z)σ8(z). This feature is of course nothing but the σ8-tension we have been addressing in this paper. It is therefore natural to run the IOI test for the different kinds of H0 measurements and also to study the consistency between the H0 and the growth data. For example, upon comparing the constraints on H0 from different methods, Lin & Ishak (2017b) observe a decrease of the IOI when the local H0 measurement is removed. From this fact they conclude that the local measurement of H0 is an outlier compared to the others, what would favour a systematics-based explanation. This situation is compatible with the observed improvement in the statistical quality of the fitting analysis by Solà, Gómez-Valent & de Cruz Pérez (2017b,c) when the local H0 measurement is removed from the overall fit of the data using the RVM and the ΛCDM. In this respect, let us mention that a recent model-independent analysis of data on cosmic chronometers and an updated compilation of SNIa seem to favour the lower range of H0 (Gómez-Valent & Amendola 2018), what would be more along the line of the results found here, which favour a theoretical interpretation of the observed σ8 and H0 tensions in terms of vacuum dynamics and in general of DDE (cf. Fig. 10).","Citation Text":["Lin & Ishak (2017b)"],"Citation Start End":[[1082,1101]]} {"Identifier":"2018MNRAS.478..126GLin_&_Ishak_(2017___b_Instance_1","Paragraph":"It may be appropriate to single out at this point the recent and interesting works by Lin & Ishak (2017a,b) in which the authors run a so-called (dis)cordance test based on using a proposed index of inconsistency (IOI) tailored at finding possible inconsistencies\/tensions between two or more data sets in a systematic and efficient way. For instance, it is well known that there is a persistent discrepancy between the Planck CMB measurements of H0 and the local measurements based on distance ladder (Riess et al. 2016, 2018b). At the same time, if one compares what is inferred from Planck 2015 best-fitting values, the LSS\/RSD measurements generally assign smaller power to the LSS data parametrized in terms of the weighted linear growth rate f(z)σ8(z). This feature is of course nothing but the σ8-tension we have been addressing in this paper. It is therefore natural to run the IOI test for the different kinds of H0 measurements and also to study the consistency between the H0 and the growth data. For example, upon comparing the constraints on H0 from different methods, Lin & Ishak (2017b) observe a decrease of the IOI when the local H0 measurement is removed. From this fact they conclude that the local measurement of H0 is an outlier compared to the others, what would favour a systematics-based explanation. This situation is compatible with the observed improvement in the statistical quality of the fitting analysis by Solà, Gómez-Valent & de Cruz Pérez (2017b,c) when the local H0 measurement is removed from the overall fit of the data using the RVM and the ΛCDM. In this respect, let us mention that a recent model-independent analysis of data on cosmic chronometers and an updated compilation of SNIa seem to favour the lower range of H0 (Gómez-Valent & Amendola 2018), what would be more along the line of the results found here, which favour a theoretical interpretation of the observed σ8 and H0 tensions in terms of vacuum dynamics and in general of DDE (cf. Fig. 10).","Citation Text":["Lin & Ishak (2017","b"],"Citation Start End":[[86,103],[105,106]]} {"Identifier":"2017ApJ...844..108M__Kruijssen_et_al._2012_Instance_1","Paragraph":"These results show that the shape of the mass function and the position of the mass peak of massive clusters have little evolution over the course of the galaxy collision of more than 1 Gyr. We note that the evolution of SCs is subjected to several destructive processes (e.g., Gnedin et al. 1999a; Fall & Zhang 2001). For low-mass clusters (\n\n\n\n\n\n), the destruction is mainly dominated by two-body relaxation processes, in which the mass of a cluster linearly decreases with time until it is destroyed. For more massive clusters, the evolution is primarily influenced by stellar evolution at early times (\n\n\n\n\n\n Myr) and by gravitational shocks at later times. These effects are included in our hydrodynamic simulations, but the mass resolution is not high enough to resolve the processes realistically, since the two-body relaxation and stellar evolution depend on individual stars. However, the cluster disruption timescale due to two-body relaxation is proportional to the cluster mass, trlx ∼ 1.7 Gyr × (Mclus\/104 \n\n\n\n\n\n)0.62 × (T\/104 Gyr−2)−0.5, where Mclus is the cluster mass and T is the tidal strength around the clusters (Kruijssen et al. 2012). Using the minimum cluster mass of \n\n\n\n\n\n in our simulation and a typical range of tidal strength in the nuclear region (since most of these clusters are concentrated around galaxy nuclei) of \n\n\n\n\n\n (Renaud 2010), we find that the range of the disruption timescale is \n\n\n\n\n\n Gyr. For more massive SCs, the timescale is even longer, beyond our run time of 1 Gyr. Therefore, the two-body relaxation may not have a major disruptive effect on these SCs. Furthermore, the mass loss timescale due to gravitational shocks (tsh) depends strongly on the cluster density, \n\n\n\n\n\n (Kruijssen et al. 2012). The majority of our clusters have a density range of \n\n\n\n\n\n, as shown in Figure 9, which suggests \n\n\n\n\n\n Gyr, much longer than the Hubble time. So gravitational shocks may not have a significant impact on the clusters in our simulation. In addition, as demonstrated by Renaud & Gieles (2013), SCs formed in galaxy mergers are also affected by the intense tidal field of the galaxies, more so for clusters in the merger remnant than for the ejected ones. We note, however, the clusters in their simulations have masses \n\n\n\n\n\n, and mass loss decreases as the cluster mass increases. For example, for a cluster to increase its mass by a factor of 2, from \n\n\n\n\n\n to \n\n\n\n\n\n, its survival rate (fraction of initial mass survived) after 1 Gyr increases from 0.6 to 0.7. Extrapolating this trend to our clusters, which are ∼10 times more massive than those in Renaud & Gieles (2013), we argue that destruction from tidal fields likely has negligible effects on the clusters we consider here.","Citation Text":["Kruijssen et al. 2012"],"Citation Start End":[[1133,1154]]} {"Identifier":"2017ApJ...844..108M__Kruijssen_et_al._2012_Instance_2","Paragraph":"These results show that the shape of the mass function and the position of the mass peak of massive clusters have little evolution over the course of the galaxy collision of more than 1 Gyr. We note that the evolution of SCs is subjected to several destructive processes (e.g., Gnedin et al. 1999a; Fall & Zhang 2001). For low-mass clusters (\n\n\n\n\n\n), the destruction is mainly dominated by two-body relaxation processes, in which the mass of a cluster linearly decreases with time until it is destroyed. For more massive clusters, the evolution is primarily influenced by stellar evolution at early times (\n\n\n\n\n\n Myr) and by gravitational shocks at later times. These effects are included in our hydrodynamic simulations, but the mass resolution is not high enough to resolve the processes realistically, since the two-body relaxation and stellar evolution depend on individual stars. However, the cluster disruption timescale due to two-body relaxation is proportional to the cluster mass, trlx ∼ 1.7 Gyr × (Mclus\/104 \n\n\n\n\n\n)0.62 × (T\/104 Gyr−2)−0.5, where Mclus is the cluster mass and T is the tidal strength around the clusters (Kruijssen et al. 2012). Using the minimum cluster mass of \n\n\n\n\n\n in our simulation and a typical range of tidal strength in the nuclear region (since most of these clusters are concentrated around galaxy nuclei) of \n\n\n\n\n\n (Renaud 2010), we find that the range of the disruption timescale is \n\n\n\n\n\n Gyr. For more massive SCs, the timescale is even longer, beyond our run time of 1 Gyr. Therefore, the two-body relaxation may not have a major disruptive effect on these SCs. Furthermore, the mass loss timescale due to gravitational shocks (tsh) depends strongly on the cluster density, \n\n\n\n\n\n (Kruijssen et al. 2012). The majority of our clusters have a density range of \n\n\n\n\n\n, as shown in Figure 9, which suggests \n\n\n\n\n\n Gyr, much longer than the Hubble time. So gravitational shocks may not have a significant impact on the clusters in our simulation. In addition, as demonstrated by Renaud & Gieles (2013), SCs formed in galaxy mergers are also affected by the intense tidal field of the galaxies, more so for clusters in the merger remnant than for the ejected ones. We note, however, the clusters in their simulations have masses \n\n\n\n\n\n, and mass loss decreases as the cluster mass increases. For example, for a cluster to increase its mass by a factor of 2, from \n\n\n\n\n\n to \n\n\n\n\n\n, its survival rate (fraction of initial mass survived) after 1 Gyr increases from 0.6 to 0.7. Extrapolating this trend to our clusters, which are ∼10 times more massive than those in Renaud & Gieles (2013), we argue that destruction from tidal fields likely has negligible effects on the clusters we consider here.","Citation Text":["Kruijssen et al. 2012"],"Citation Start End":[[1726,1747]]} {"Identifier":"2020MNRAS.499.5562Z__Dai_et_al._2015_Instance_1","Paragraph":"The second significant source of energy dissipation is stream–stream collisions near apocenter from GR apsidal precssion. As in Dai, McKinney & Miller (2015) and Bonnerot et al. (2017), we calculate the ingoing collision stream velocities by finding the intersection point of two elliptical orbits, shifted by an instantaneous pericenter shift δϖ from GR apsidal precession. Since an eccentric orbit undergoes apsidal precession at a rate (assuming af ≫ Rg)\n(24)$$\\begin{eqnarray*}\r\n\\left. \\frac{\\partial \\varpi }{\\partial t} \\right|_{\\rm GR} = \\frac{3 R_{\\rm g}n}{a (1-e^2)},\r\n\\end{eqnarray*}$$we have after one orbital period\n(25)$$\\begin{eqnarray*}\r\n\\delta \\varpi \\simeq \\frac{3 \\pi R_{\\rm g}}{r_{\\rm p}} = 11.5^\\circ \\, \\beta \\frac{\\bar{M}_\\bullet ^{2\/3} \\bar{M}_\\star ^{1\/3}}{\\bar{R}_\\star }.\r\n\\end{eqnarray*}$$With δϖ, one can calculate the relative stream velocities during the collision, leading to a loss of energy of (Dai et al. 2015; Bonnerot et al. 2017)\n(26)$$\\begin{eqnarray*}\r\n\\delta E_{\\rm ss} &=& \\frac{e_{\\rm f}^2 G M_\\bullet }{2a_{\\rm f}(1-e_{\\rm f}^2)} \\sin ^2 \\left(\\frac{\\delta \\varpi }{2} \\right) \\simeq \\frac{G M_\\bullet }{4 r_{\\rm p}} \\sin ^2 \\left(\\frac{\\delta \\varpi }{2} \\right),\r\n\\end{eqnarray*}$$hence\n(27)$$\\begin{eqnarray*}\r\n\\mathcal {V}_{\\rm ss} = \\frac{\\delta E_{\\rm ss}}{E_{\\rm f}} = \\frac{a_{\\rm f}}{2 r_{\\rm p}} \\sin ^2 \\left(\\frac{\\delta \\varpi }{2} \\right).\r\n\\end{eqnarray*}$$When δϖ ≪ 1, equation (27) reduces to\n(28)$$\\begin{eqnarray*}\r\n\\mathcal {V}_{\\rm ss} \\simeq \\frac{9 \\pi ^2}{16} \\frac{R_{\\rm g}^2 a_{\\rm f}}{r_{\\rm p}^3} = 0.125 \\, \\beta ^3 \\frac{\\bar{M}_\\bullet ^{5\/3} \\bar{M}_\\star ^{1\/3}}{\\bar{R}_\\star ^2} \\left(\\frac{t}{t_{\\rm f0}} \\right)^{2\/3}.\r\n\\end{eqnarray*}$$Different sources of energy dissipation need to be compared with the total loss of energy required to completely circularize the disc. If the debris circularizes with constant orbital angular momentum, the final semimajor axis is given by $a_{\\rm circ} = (1 - e_{\\rm f}^2)a_{\\rm f}\\simeq 2 r_{\\rm p}$. Hence the orbital energy of a completely circularized debris stream is given by\n(29)$$\\begin{eqnarray*}\r\nE_{\\rm circ} = - \\frac{G M_\\bullet }{4 r_{\\rm p}},\r\n\\end{eqnarray*}$$so the fractional binding energy which must be lost to circularize the stream is\n(30)$$\\begin{eqnarray*}\r\n\\mathcal {V}_{\\rm circ} = \\frac{E_{\\rm circ}}{E_{\\rm f}} = \\frac{R_{\\rm t}^2}{4 r_{\\rm p}R_\\star } \\left(\\frac{t}{t_{\\rm f0}} \\right)^{2\/3} = \\frac{25}{\\beta } \\frac{\\bar{M}_\\bullet ^{1\/3}}{\\bar{M}_\\star ^{1\/3}} \\left(\\frac{t}{t_{\\rm f0}} \\right)^{2\/3}.\r\n\\end{eqnarray*}$$We see that $\\mathcal {V}_{\\rm circ} \\gg 1$ for typical parameters.","Citation Text":["Dai et al. 2015"],"Citation Start End":[[928,943]]} {"Identifier":"2020AandA...636A.115D__Nissen_&_Schuster_(2010)_Instance_1","Paragraph":"While a non-negligible fraction of stars have disc-like kinematics, the majority of the UIP stars, as well as the VMP and EMP stars, have halo-like kinematics. This does not necessarily mean that they are all accreted, since a fraction of the halo can be made of stars formerly in the disc, but later kinematically heated to halo kinematics by one or several satellite accretions. This has indeed proven to be the dominant in-situ mode of formation of the Galactic halo for stars at higher metallicities, and at few kpc from the Sun (see Di Matteo et al. 2019), as we discuss more extensively in the next section. It is, however, interesting to note that, compared to stars at higher metallicities, such as stars in the Nissen & Schuster sample and stars in the Gaia DR2-APOGEE sample (middle and right columns in Fig. 5), in the Toomre diagram, the UIP and LP samples seem to lack stars with null angular momentum, meaning along the Lz = 0 line. At values of \n\n\n\n\n\n(\n\n\n\nV\nR\n\n\n2\n\n+\n\n\n\nV\nZ\n\n\n2\n\n)\n\n\n≳\n200\n\n\n$ \\sqrt{({V_R}^2+{V_Z}^2)} \\gtrsim 200 $\n\n\n km s−1, stars with [Fe\/H]   −4 have rather prograde or retrograde motions, but none seem to lie along the sequence of accreted halo stars discovered by Nissen & Schuster (2010), and later confirmed in Gaia DR1 and DR2 data by Belokurov et al. (2018) (Gaia Sausage), Haywood et al. (2018), Helmi et al. (2018) (Gaia Enceladus). The Gaia Sausage, which is this group of halo stars with very radial orbits, and null VΦ, seems to indeed disappear at [Fe\/H]   −2 in this plane. We emphasise that this apparent difference between the kinematics of VMP and EMP stars, on the one side, and stars with [Fe\/H] >  −2, on the other side, is simply the consequence of these stars probing different regions and distances from the Galactic centre. Indeed, when one compares the kinematics of these different samples of stars in the quasi-integral-of-motion space Lz − Lperp plane (see Fig. 5, second row), rather than in the Toomre diagram, the kinematic properties of these samples are the same, over the whole [Fe\/H] interval. Before moving further, we need, however, to emphasise two points of the comparison with samples at higher metallicity. Firstly, when compared to the Nissen & Schuster (2010) sample, which, we remind the reader, is a kinematically selected sample of thick disc and halo stars, the VMP and EMP stars in the LP First stars sample show an excess of stars at retrograde motions (positive Lz, i.e. Lz >  5) and high values of Lperp (Lperp >  15). None of the Nissen & Schuster (2010) stars occupy this region of the Lz − Lperp diagram, and we suggest this is a consequence of the “local” character of stars in the Nissen & Schuster (2010) study, which are all limited to a few hundred parsecs from the Sun. Indeed, when VMP and EMP stars are compared to stars in the Gaia DR2-APOGEE sample, one can see that stars with Lz and Lperp as extreme as Lz >  5 and Lperp >  15 are found also in the latter. Secondly, because in the comparison shown in this figure we used all stars in the Gaia DR2-APOGEE sample, not restricting ourself to stars from the kinematically defined thick disc and halo, the reader will not be surprised to find that the majority of stars in Gaia DR2-APOGEE sample are stars with cold (i.e. thin) disc-like kinematics, their distribution peaking at Lz ∼ 20 and Lperp ≤ 5. At this stage, what is important to retain is that the region occupied by all these samples, independently of their [Fe\/H] ratio, is the same: the relative fraction of stars in one or in another region of the space under analysis can change from one sample to another, but not their overall distribution.","Citation Text":["Nissen & Schuster (2010)"],"Citation Start End":[[1202,1226]]} {"Identifier":"2020AandA...636A.115D__Nissen_&_Schuster_(2010)_Instance_2","Paragraph":"While a non-negligible fraction of stars have disc-like kinematics, the majority of the UIP stars, as well as the VMP and EMP stars, have halo-like kinematics. This does not necessarily mean that they are all accreted, since a fraction of the halo can be made of stars formerly in the disc, but later kinematically heated to halo kinematics by one or several satellite accretions. This has indeed proven to be the dominant in-situ mode of formation of the Galactic halo for stars at higher metallicities, and at few kpc from the Sun (see Di Matteo et al. 2019), as we discuss more extensively in the next section. It is, however, interesting to note that, compared to stars at higher metallicities, such as stars in the Nissen & Schuster sample and stars in the Gaia DR2-APOGEE sample (middle and right columns in Fig. 5), in the Toomre diagram, the UIP and LP samples seem to lack stars with null angular momentum, meaning along the Lz = 0 line. At values of \n\n\n\n\n\n(\n\n\n\nV\nR\n\n\n2\n\n+\n\n\n\nV\nZ\n\n\n2\n\n)\n\n\n≳\n200\n\n\n$ \\sqrt{({V_R}^2+{V_Z}^2)} \\gtrsim 200 $\n\n\n km s−1, stars with [Fe\/H]   −4 have rather prograde or retrograde motions, but none seem to lie along the sequence of accreted halo stars discovered by Nissen & Schuster (2010), and later confirmed in Gaia DR1 and DR2 data by Belokurov et al. (2018) (Gaia Sausage), Haywood et al. (2018), Helmi et al. (2018) (Gaia Enceladus). The Gaia Sausage, which is this group of halo stars with very radial orbits, and null VΦ, seems to indeed disappear at [Fe\/H]   −2 in this plane. We emphasise that this apparent difference between the kinematics of VMP and EMP stars, on the one side, and stars with [Fe\/H] >  −2, on the other side, is simply the consequence of these stars probing different regions and distances from the Galactic centre. Indeed, when one compares the kinematics of these different samples of stars in the quasi-integral-of-motion space Lz − Lperp plane (see Fig. 5, second row), rather than in the Toomre diagram, the kinematic properties of these samples are the same, over the whole [Fe\/H] interval. Before moving further, we need, however, to emphasise two points of the comparison with samples at higher metallicity. Firstly, when compared to the Nissen & Schuster (2010) sample, which, we remind the reader, is a kinematically selected sample of thick disc and halo stars, the VMP and EMP stars in the LP First stars sample show an excess of stars at retrograde motions (positive Lz, i.e. Lz >  5) and high values of Lperp (Lperp >  15). None of the Nissen & Schuster (2010) stars occupy this region of the Lz − Lperp diagram, and we suggest this is a consequence of the “local” character of stars in the Nissen & Schuster (2010) study, which are all limited to a few hundred parsecs from the Sun. Indeed, when VMP and EMP stars are compared to stars in the Gaia DR2-APOGEE sample, one can see that stars with Lz and Lperp as extreme as Lz >  5 and Lperp >  15 are found also in the latter. Secondly, because in the comparison shown in this figure we used all stars in the Gaia DR2-APOGEE sample, not restricting ourself to stars from the kinematically defined thick disc and halo, the reader will not be surprised to find that the majority of stars in Gaia DR2-APOGEE sample are stars with cold (i.e. thin) disc-like kinematics, their distribution peaking at Lz ∼ 20 and Lperp ≤ 5. At this stage, what is important to retain is that the region occupied by all these samples, independently of their [Fe\/H] ratio, is the same: the relative fraction of stars in one or in another region of the space under analysis can change from one sample to another, but not their overall distribution.","Citation Text":["Nissen & Schuster (2010)"],"Citation Start End":[[2213,2237]]} {"Identifier":"2020AandA...636A.115D__Nissen_&_Schuster_(2010)_Instance_3","Paragraph":"While a non-negligible fraction of stars have disc-like kinematics, the majority of the UIP stars, as well as the VMP and EMP stars, have halo-like kinematics. This does not necessarily mean that they are all accreted, since a fraction of the halo can be made of stars formerly in the disc, but later kinematically heated to halo kinematics by one or several satellite accretions. This has indeed proven to be the dominant in-situ mode of formation of the Galactic halo for stars at higher metallicities, and at few kpc from the Sun (see Di Matteo et al. 2019), as we discuss more extensively in the next section. It is, however, interesting to note that, compared to stars at higher metallicities, such as stars in the Nissen & Schuster sample and stars in the Gaia DR2-APOGEE sample (middle and right columns in Fig. 5), in the Toomre diagram, the UIP and LP samples seem to lack stars with null angular momentum, meaning along the Lz = 0 line. At values of \n\n\n\n\n\n(\n\n\n\nV\nR\n\n\n2\n\n+\n\n\n\nV\nZ\n\n\n2\n\n)\n\n\n≳\n200\n\n\n$ \\sqrt{({V_R}^2+{V_Z}^2)} \\gtrsim 200 $\n\n\n km s−1, stars with [Fe\/H]   −4 have rather prograde or retrograde motions, but none seem to lie along the sequence of accreted halo stars discovered by Nissen & Schuster (2010), and later confirmed in Gaia DR1 and DR2 data by Belokurov et al. (2018) (Gaia Sausage), Haywood et al. (2018), Helmi et al. (2018) (Gaia Enceladus). The Gaia Sausage, which is this group of halo stars with very radial orbits, and null VΦ, seems to indeed disappear at [Fe\/H]   −2 in this plane. We emphasise that this apparent difference between the kinematics of VMP and EMP stars, on the one side, and stars with [Fe\/H] >  −2, on the other side, is simply the consequence of these stars probing different regions and distances from the Galactic centre. Indeed, when one compares the kinematics of these different samples of stars in the quasi-integral-of-motion space Lz − Lperp plane (see Fig. 5, second row), rather than in the Toomre diagram, the kinematic properties of these samples are the same, over the whole [Fe\/H] interval. Before moving further, we need, however, to emphasise two points of the comparison with samples at higher metallicity. Firstly, when compared to the Nissen & Schuster (2010) sample, which, we remind the reader, is a kinematically selected sample of thick disc and halo stars, the VMP and EMP stars in the LP First stars sample show an excess of stars at retrograde motions (positive Lz, i.e. Lz >  5) and high values of Lperp (Lperp >  15). None of the Nissen & Schuster (2010) stars occupy this region of the Lz − Lperp diagram, and we suggest this is a consequence of the “local” character of stars in the Nissen & Schuster (2010) study, which are all limited to a few hundred parsecs from the Sun. Indeed, when VMP and EMP stars are compared to stars in the Gaia DR2-APOGEE sample, one can see that stars with Lz and Lperp as extreme as Lz >  5 and Lperp >  15 are found also in the latter. Secondly, because in the comparison shown in this figure we used all stars in the Gaia DR2-APOGEE sample, not restricting ourself to stars from the kinematically defined thick disc and halo, the reader will not be surprised to find that the majority of stars in Gaia DR2-APOGEE sample are stars with cold (i.e. thin) disc-like kinematics, their distribution peaking at Lz ∼ 20 and Lperp ≤ 5. At this stage, what is important to retain is that the region occupied by all these samples, independently of their [Fe\/H] ratio, is the same: the relative fraction of stars in one or in another region of the space under analysis can change from one sample to another, but not their overall distribution.","Citation Text":["Nissen & Schuster (2010)"],"Citation Start End":[[2517,2541]]} {"Identifier":"2020AandA...636A.115D__Nissen_&_Schuster_(2010)_Instance_4","Paragraph":"While a non-negligible fraction of stars have disc-like kinematics, the majority of the UIP stars, as well as the VMP and EMP stars, have halo-like kinematics. This does not necessarily mean that they are all accreted, since a fraction of the halo can be made of stars formerly in the disc, but later kinematically heated to halo kinematics by one or several satellite accretions. This has indeed proven to be the dominant in-situ mode of formation of the Galactic halo for stars at higher metallicities, and at few kpc from the Sun (see Di Matteo et al. 2019), as we discuss more extensively in the next section. It is, however, interesting to note that, compared to stars at higher metallicities, such as stars in the Nissen & Schuster sample and stars in the Gaia DR2-APOGEE sample (middle and right columns in Fig. 5), in the Toomre diagram, the UIP and LP samples seem to lack stars with null angular momentum, meaning along the Lz = 0 line. At values of \n\n\n\n\n\n(\n\n\n\nV\nR\n\n\n2\n\n+\n\n\n\nV\nZ\n\n\n2\n\n)\n\n\n≳\n200\n\n\n$ \\sqrt{({V_R}^2+{V_Z}^2)} \\gtrsim 200 $\n\n\n km s−1, stars with [Fe\/H]   −4 have rather prograde or retrograde motions, but none seem to lie along the sequence of accreted halo stars discovered by Nissen & Schuster (2010), and later confirmed in Gaia DR1 and DR2 data by Belokurov et al. (2018) (Gaia Sausage), Haywood et al. (2018), Helmi et al. (2018) (Gaia Enceladus). The Gaia Sausage, which is this group of halo stars with very radial orbits, and null VΦ, seems to indeed disappear at [Fe\/H]   −2 in this plane. We emphasise that this apparent difference between the kinematics of VMP and EMP stars, on the one side, and stars with [Fe\/H] >  −2, on the other side, is simply the consequence of these stars probing different regions and distances from the Galactic centre. Indeed, when one compares the kinematics of these different samples of stars in the quasi-integral-of-motion space Lz − Lperp plane (see Fig. 5, second row), rather than in the Toomre diagram, the kinematic properties of these samples are the same, over the whole [Fe\/H] interval. Before moving further, we need, however, to emphasise two points of the comparison with samples at higher metallicity. Firstly, when compared to the Nissen & Schuster (2010) sample, which, we remind the reader, is a kinematically selected sample of thick disc and halo stars, the VMP and EMP stars in the LP First stars sample show an excess of stars at retrograde motions (positive Lz, i.e. Lz >  5) and high values of Lperp (Lperp >  15). None of the Nissen & Schuster (2010) stars occupy this region of the Lz − Lperp diagram, and we suggest this is a consequence of the “local” character of stars in the Nissen & Schuster (2010) study, which are all limited to a few hundred parsecs from the Sun. Indeed, when VMP and EMP stars are compared to stars in the Gaia DR2-APOGEE sample, one can see that stars with Lz and Lperp as extreme as Lz >  5 and Lperp >  15 are found also in the latter. Secondly, because in the comparison shown in this figure we used all stars in the Gaia DR2-APOGEE sample, not restricting ourself to stars from the kinematically defined thick disc and halo, the reader will not be surprised to find that the majority of stars in Gaia DR2-APOGEE sample are stars with cold (i.e. thin) disc-like kinematics, their distribution peaking at Lz ∼ 20 and Lperp ≤ 5. At this stage, what is important to retain is that the region occupied by all these samples, independently of their [Fe\/H] ratio, is the same: the relative fraction of stars in one or in another region of the space under analysis can change from one sample to another, but not their overall distribution.","Citation Text":["Nissen & Schuster (2010)"],"Citation Start End":[[2672,2696]]} {"Identifier":"2015ApJ...809L..20M__Thommes_et_al._2008_Instance_1","Paragraph":"In this Letter we propose to address these apparent difficulties and account for many of the observed differences between the properties of planets in cool and hot stars by postulating that, in addition to the tidal interaction with existing close-in planets, a large fraction of the stellar hosts—both cool and hot—ingest a hot Jupiter early on in their evolution. This proposal is motivated by the expectation that a large fraction (up to 80% according to Trilling et al. 2002) of solar-type stars possess giant planets during their pre-MS phase, and that a large fraction of the giant planets that form in a protoplanetary disk on scales \n\n\n\n\n\n migrate close to their host star before the disk is dispersed (e.g., Ida & Lin 2004). Numerical simulations incorporating an N-body code and a 1D α-viscosity disk model (Thommes et al. 2008) demonstrated that this behavior can be expected for disks with \n\n\n\n\n\n that are sufficiently massive. The inward planet migration is likely stopped by the strong (\n\n\n\n\n\n kG) protostellar magnetic field that truncates the disk at a radius (rin) of a few stellar radii (e.g., Lin et al. 1996). Gravitational interaction with the disk causes a planet reaching rin to penetrate into the magnetospheric cavity and, if it is massive enough, to undergo eccentricity excitation that can rapidly lead to a collision with the star (e.g., Rice et al. 2008). It was, however, inferred that if Mp is sufficiently small (\n\n\n\n\n\n), the planet would remain stranded at a distance where its orbital period is ∼0.5 of that at rin until well after the gas disk disappears (on a timescale of ∼ 106–107 years). In our proposed scenario, the primordial disk orientations span a broad angular range that is reflected in the orbital orientations of the stranded planets. When the latter are ingested by tidal interaction with the host star (on a timescale \n\n\n\n\n\n Gyr), the absorbed angular momentum is sufficient to align a solar-mass star in that general direction, but not an MS star with \n\n\n\n\n\n K. This is because cool stars have significantly lower angular momenta at the time of ingestion than hot stars as a result of a more efficient magnetic braking process and of a lower moment of inertia. Given the proximity of the stranded HJs (SHJs) to their host stars (\n\n\n\n\n\ndays), they can be expected to have been ingested by the time their parent planetary systems are observed; however, giant planets farther out can continue to interact with their host stars and potentially affect their measured obliquities. In our simplified formulation, we model the SHJs using as parameters their characteristic mass MSHJ and the fraction p of systems that initially harbored an SHJ. By comparing the predictions of this model with the observational data, we infer \n\n\n\n\n\n and \n\n\n\n\n\n.","Citation Text":["Thommes et al. 2008"],"Citation Start End":[[818,837]]} {"Identifier":"2020MNRAS.495.4071M__Prandoni_et_al._2018_Instance_1","Paragraph":"Low-frequency observation of radio sky is also essential for the study of the astrophysics at play in various evolutionary stages of different Galactic and extragalactic sources. Radio emission at low frequencies, together with their redshift information, can be used to infer several astrophysical properties associated with the sources. In general, the source distribution is assumed Poissonian (with the possibility of clustering following single power law) (Ali et al. 2008; Jelić et al. 2010; Trott et al. 2016). Source counts are also modelled via a single power-law distribution (Hurley-Walker et al. 2016; Intema et al. 2017; Franzen et al. 2019). However, several recent studies have shown deviation from the single power-law model (Williams et al. 2016; Prandoni et al. 2018; Hale et al. 2019). Thus more detailed studies both in wide field as well as deep fields are required for generating a fiducial model of sources at low frequencies. The differential source counts at these are also useful for constraining the nature of sources. At frequencies in the GHz range and upwards, the source properties are well characterized. However, at lower frequencies, there is a lack of consensus for the same. It has been seen in previous studies that at these frequencies, AGNs dominate in the flux density scales down to few 100 μJy while SFGs and radio quite AGNs become dominant below ∼100 μJy (Simpson et al. 2006; Mignano et al. 2008; Seymour et al. 2008; Smolčić et al. 2008; Padovani et al. 2009, 2011, 2015; Prandoni et al. 2018; Hale et al. 2019). This is inferred from the flattening of the source counts below 1 mJy. However, such studies are very few on account of the limitations in reaching the required SNR. Thus empirical constraints at frequencies ≲1.4 GHz are limited. Therefore the study of the low-frequency radio sky is vital for fiducial modelling of foregrounds for 21-cm cosmology as well as constraining the physics and the astrophysics of the sources.","Citation Text":["Prandoni et al. 2018"],"Citation Start End":[[764,784]]} {"Identifier":"2020MNRAS.495.4071M__Prandoni_et_al._2018_Instance_2","Paragraph":"Low-frequency observation of radio sky is also essential for the study of the astrophysics at play in various evolutionary stages of different Galactic and extragalactic sources. Radio emission at low frequencies, together with their redshift information, can be used to infer several astrophysical properties associated with the sources. In general, the source distribution is assumed Poissonian (with the possibility of clustering following single power law) (Ali et al. 2008; Jelić et al. 2010; Trott et al. 2016). Source counts are also modelled via a single power-law distribution (Hurley-Walker et al. 2016; Intema et al. 2017; Franzen et al. 2019). However, several recent studies have shown deviation from the single power-law model (Williams et al. 2016; Prandoni et al. 2018; Hale et al. 2019). Thus more detailed studies both in wide field as well as deep fields are required for generating a fiducial model of sources at low frequencies. The differential source counts at these are also useful for constraining the nature of sources. At frequencies in the GHz range and upwards, the source properties are well characterized. However, at lower frequencies, there is a lack of consensus for the same. It has been seen in previous studies that at these frequencies, AGNs dominate in the flux density scales down to few 100 μJy while SFGs and radio quite AGNs become dominant below ∼100 μJy (Simpson et al. 2006; Mignano et al. 2008; Seymour et al. 2008; Smolčić et al. 2008; Padovani et al. 2009, 2011, 2015; Prandoni et al. 2018; Hale et al. 2019). This is inferred from the flattening of the source counts below 1 mJy. However, such studies are very few on account of the limitations in reaching the required SNR. Thus empirical constraints at frequencies ≲1.4 GHz are limited. Therefore the study of the low-frequency radio sky is vital for fiducial modelling of foregrounds for 21-cm cosmology as well as constraining the physics and the astrophysics of the sources.","Citation Text":["Prandoni et al. 2018"],"Citation Start End":[[1518,1538]]} {"Identifier":"2020MNRAS.495.4071MJelić_et_al._2010_Instance_1","Paragraph":"Low-frequency observation of radio sky is also essential for the study of the astrophysics at play in various evolutionary stages of different Galactic and extragalactic sources. Radio emission at low frequencies, together with their redshift information, can be used to infer several astrophysical properties associated with the sources. In general, the source distribution is assumed Poissonian (with the possibility of clustering following single power law) (Ali et al. 2008; Jelić et al. 2010; Trott et al. 2016). Source counts are also modelled via a single power-law distribution (Hurley-Walker et al. 2016; Intema et al. 2017; Franzen et al. 2019). However, several recent studies have shown deviation from the single power-law model (Williams et al. 2016; Prandoni et al. 2018; Hale et al. 2019). Thus more detailed studies both in wide field as well as deep fields are required for generating a fiducial model of sources at low frequencies. The differential source counts at these are also useful for constraining the nature of sources. At frequencies in the GHz range and upwards, the source properties are well characterized. However, at lower frequencies, there is a lack of consensus for the same. It has been seen in previous studies that at these frequencies, AGNs dominate in the flux density scales down to few 100 μJy while SFGs and radio quite AGNs become dominant below ∼100 μJy (Simpson et al. 2006; Mignano et al. 2008; Seymour et al. 2008; Smolčić et al. 2008; Padovani et al. 2009, 2011, 2015; Prandoni et al. 2018; Hale et al. 2019). This is inferred from the flattening of the source counts below 1 mJy. However, such studies are very few on account of the limitations in reaching the required SNR. Thus empirical constraints at frequencies ≲1.4 GHz are limited. Therefore the study of the low-frequency radio sky is vital for fiducial modelling of foregrounds for 21-cm cosmology as well as constraining the physics and the astrophysics of the sources.","Citation Text":["Jelić et al. 2010"],"Citation Start End":[[479,496]]} {"Identifier":"2021AandA...656A.148R__Sakai_et_al._2012_Instance_1","Paragraph":"Applying the P&T profiles defined in Sect. 2 for the three regions of IRAS 16293 our computations imply that 56 mechanisms possess valid reaction thermodynamic function values to proceed with the formation of H2CO. Twenty-six of these can produce H2CO in region I, 32 in region II, and 33 in region III (please see Table 7). These are the amended reactions with detected reagents in every region of the disk. The presence of methane (CH4) and neutral atomic carbon (CI) in this astronomical object, in addition to trans-HONO in region III (detected at ~ 150 AU from the core – Coutens et al. 2019), confirms the hypothetical feasibility of these mechanisms. Moreover, because nitrosyl hydride (HNO) has not been detected in IRAS 16293, R84 cannot be included in any circumstellar envelope region, as it was in DCDMCs. In Fig. 3 we show the abundance of reactants and formaldehyde itself already detected in the three regions of the disk. They have been calculated for the methylene (⋅ 3CH2) (Vasyunin & Herbst 2013), methyl radical (⋅CH3) (Sakai et al. 2012; Woon 2002), and methane (CH4) (Sakai et al. 2012) ground electronic state abundances rather than detected. The reason is that they are planar (or linear) symmetric-top molecules and therefore have a small permanent electric dipole moment, which makes them undetectable through terrestrial radio telescopes by rotational spectroscopy. On the other side of the spectrum, neither high-resolution infrared absorption nor ultraviolet-visible spectroscopy telescopes can identify them in the gas-phase because they lack of a powerful enough source of electromagnetic radiation. The abundance values for the triplet ground-state of methylene (⋅CH2(X3B1)) have therefore been estimated by using Monte Carlo algorithms (Vasyunin & Herbst 2013) which in turn are based on known abundances of derived species. The presence of the methyl radical (⋅CH3) in region I just before the CO depletion zone from icy grains should be negligible because ⋅CH3 is thought tobe mainly produced in this region by CH4 photodissociation (Sakai et al. 2012) and CH3OH (Woon 2002) desorbs from the grains in region II. Consequently, reactions based on ⋅CH3 were considered only for regions II and III, assuming for both an abundance of 6.40 × 10−9 cm−3 (Sakai et al. 2012).","Citation Text":["Sakai et al. 2012"],"Citation Start End":[[1040,1057]]} {"Identifier":"2021AandA...656A.148R__Sakai_et_al._2012_Instance_2","Paragraph":"Applying the P&T profiles defined in Sect. 2 for the three regions of IRAS 16293 our computations imply that 56 mechanisms possess valid reaction thermodynamic function values to proceed with the formation of H2CO. Twenty-six of these can produce H2CO in region I, 32 in region II, and 33 in region III (please see Table 7). These are the amended reactions with detected reagents in every region of the disk. The presence of methane (CH4) and neutral atomic carbon (CI) in this astronomical object, in addition to trans-HONO in region III (detected at ~ 150 AU from the core – Coutens et al. 2019), confirms the hypothetical feasibility of these mechanisms. Moreover, because nitrosyl hydride (HNO) has not been detected in IRAS 16293, R84 cannot be included in any circumstellar envelope region, as it was in DCDMCs. In Fig. 3 we show the abundance of reactants and formaldehyde itself already detected in the three regions of the disk. They have been calculated for the methylene (⋅ 3CH2) (Vasyunin & Herbst 2013), methyl radical (⋅CH3) (Sakai et al. 2012; Woon 2002), and methane (CH4) (Sakai et al. 2012) ground electronic state abundances rather than detected. The reason is that they are planar (or linear) symmetric-top molecules and therefore have a small permanent electric dipole moment, which makes them undetectable through terrestrial radio telescopes by rotational spectroscopy. On the other side of the spectrum, neither high-resolution infrared absorption nor ultraviolet-visible spectroscopy telescopes can identify them in the gas-phase because they lack of a powerful enough source of electromagnetic radiation. The abundance values for the triplet ground-state of methylene (⋅CH2(X3B1)) have therefore been estimated by using Monte Carlo algorithms (Vasyunin & Herbst 2013) which in turn are based on known abundances of derived species. The presence of the methyl radical (⋅CH3) in region I just before the CO depletion zone from icy grains should be negligible because ⋅CH3 is thought tobe mainly produced in this region by CH4 photodissociation (Sakai et al. 2012) and CH3OH (Woon 2002) desorbs from the grains in region II. Consequently, reactions based on ⋅CH3 were considered only for regions II and III, assuming for both an abundance of 6.40 × 10−9 cm−3 (Sakai et al. 2012).","Citation Text":["Sakai et al. 2012"],"Citation Start End":[[1090,1107]]} {"Identifier":"2021AandA...656A.148R__Sakai_et_al._2012_Instance_3","Paragraph":"Applying the P&T profiles defined in Sect. 2 for the three regions of IRAS 16293 our computations imply that 56 mechanisms possess valid reaction thermodynamic function values to proceed with the formation of H2CO. Twenty-six of these can produce H2CO in region I, 32 in region II, and 33 in region III (please see Table 7). These are the amended reactions with detected reagents in every region of the disk. The presence of methane (CH4) and neutral atomic carbon (CI) in this astronomical object, in addition to trans-HONO in region III (detected at ~ 150 AU from the core – Coutens et al. 2019), confirms the hypothetical feasibility of these mechanisms. Moreover, because nitrosyl hydride (HNO) has not been detected in IRAS 16293, R84 cannot be included in any circumstellar envelope region, as it was in DCDMCs. In Fig. 3 we show the abundance of reactants and formaldehyde itself already detected in the three regions of the disk. They have been calculated for the methylene (⋅ 3CH2) (Vasyunin & Herbst 2013), methyl radical (⋅CH3) (Sakai et al. 2012; Woon 2002), and methane (CH4) (Sakai et al. 2012) ground electronic state abundances rather than detected. The reason is that they are planar (or linear) symmetric-top molecules and therefore have a small permanent electric dipole moment, which makes them undetectable through terrestrial radio telescopes by rotational spectroscopy. On the other side of the spectrum, neither high-resolution infrared absorption nor ultraviolet-visible spectroscopy telescopes can identify them in the gas-phase because they lack of a powerful enough source of electromagnetic radiation. The abundance values for the triplet ground-state of methylene (⋅CH2(X3B1)) have therefore been estimated by using Monte Carlo algorithms (Vasyunin & Herbst 2013) which in turn are based on known abundances of derived species. The presence of the methyl radical (⋅CH3) in region I just before the CO depletion zone from icy grains should be negligible because ⋅CH3 is thought tobe mainly produced in this region by CH4 photodissociation (Sakai et al. 2012) and CH3OH (Woon 2002) desorbs from the grains in region II. Consequently, reactions based on ⋅CH3 were considered only for regions II and III, assuming for both an abundance of 6.40 × 10−9 cm−3 (Sakai et al. 2012).","Citation Text":["Sakai et al. 2012"],"Citation Start End":[[2069,2086]]} {"Identifier":"2021AandA...656A.148R__Sakai_et_al._2012_Instance_4","Paragraph":"Applying the P&T profiles defined in Sect. 2 for the three regions of IRAS 16293 our computations imply that 56 mechanisms possess valid reaction thermodynamic function values to proceed with the formation of H2CO. Twenty-six of these can produce H2CO in region I, 32 in region II, and 33 in region III (please see Table 7). These are the amended reactions with detected reagents in every region of the disk. The presence of methane (CH4) and neutral atomic carbon (CI) in this astronomical object, in addition to trans-HONO in region III (detected at ~ 150 AU from the core – Coutens et al. 2019), confirms the hypothetical feasibility of these mechanisms. Moreover, because nitrosyl hydride (HNO) has not been detected in IRAS 16293, R84 cannot be included in any circumstellar envelope region, as it was in DCDMCs. In Fig. 3 we show the abundance of reactants and formaldehyde itself already detected in the three regions of the disk. They have been calculated for the methylene (⋅ 3CH2) (Vasyunin & Herbst 2013), methyl radical (⋅CH3) (Sakai et al. 2012; Woon 2002), and methane (CH4) (Sakai et al. 2012) ground electronic state abundances rather than detected. The reason is that they are planar (or linear) symmetric-top molecules and therefore have a small permanent electric dipole moment, which makes them undetectable through terrestrial radio telescopes by rotational spectroscopy. On the other side of the spectrum, neither high-resolution infrared absorption nor ultraviolet-visible spectroscopy telescopes can identify them in the gas-phase because they lack of a powerful enough source of electromagnetic radiation. The abundance values for the triplet ground-state of methylene (⋅CH2(X3B1)) have therefore been estimated by using Monte Carlo algorithms (Vasyunin & Herbst 2013) which in turn are based on known abundances of derived species. The presence of the methyl radical (⋅CH3) in region I just before the CO depletion zone from icy grains should be negligible because ⋅CH3 is thought tobe mainly produced in this region by CH4 photodissociation (Sakai et al. 2012) and CH3OH (Woon 2002) desorbs from the grains in region II. Consequently, reactions based on ⋅CH3 were considered only for regions II and III, assuming for both an abundance of 6.40 × 10−9 cm−3 (Sakai et al. 2012).","Citation Text":["Sakai et al. 2012"],"Citation Start End":[[2283,2300]]} {"Identifier":"2017ApJ...838..132O__Gillmon_et_al._2006_Instance_1","Paragraph":"Fukui et al. (2014, 2015) compared the Planck dust data and the gas emission data such as \n\n\n\n\n\n and \n\n\n\n\n\n for the solar neighborhood. The \n\n\n\n\n\n emission is generally assumed to be optically thin, as written in textbooks. If the dust properties are uniform and DGR is a constant, it is expected that the velocity-integrated intensity of the \n\n\n\n\n\n spectrum (\n\n\n\n\n\n) is proportional to \n\n\n\n\n\n for the data points where the \n\n\n\n\n\n emission is not detected. Fukui et al. (2014, 2015), however, found that the correlation between them is not so good. By introducing \n\n\n\n\n\n into the \n\n\n\n\n\n correlation plot, these authors discovered that the poor correlation in the \n\n\n\n\n\n plot is mainly due to the data points where the density is high and \n\n\n\n\n\n is low. There are two main possibilities to explain this bad correlation between \n\n\n\n\n\n and \n\n\n\n\n\n one is the presence of optically thick \n\n\n\n\n\n gas, and the other is the presence of “\n\n\n\n\n\n-dark \n\n\n\n\n\n gas,” which is \n\n\n\n\n\n gas without the \n\n\n\n\n\n emission (e.g., Wolfire et al. 2010; Planck Collaboration et al. 2011c; Langer et al. 2014). Fukui et al. (2014, 2015) investigated the \n\n\n\n\n\n fractions in the hydrogen gas by referring to the UV measurements (Gillmon et al. 2006), and found that the fractions are typically \n\n\n\n\n\n toward the lines of sight whose column densities are up to at least \n\n\n\n\n\n.1\n\n1\nNote that in Figure 16 of Fukui et al. (2015), the \n\n\n\n\n\n fractions are somewhat larger than 10% toward two Galactic B-type stars, HD 210121 and HD 102065 (Rachford et al. 2002). These two stars may be contaminated by their own localized gas, and therefore the \n\n\n\n\n\n fractions for the local ISM are possibly not reliable toward them. For this reason, Fukui et al. (2017; see Section 4.3) did not use the results obtained in Rachford et al. (2002).\n That is, \n\n\n\n\n\n dominates \n\n\n\n\n\n, and the “\n\n\n\n\n\n-dark \n\n\n\n\n\n gas” would not be a dominant component in the local ISM. Therefore, these authors concluded that there exists a large amount of optically thick \n\n\n\n\n\n gas in the local ISM, whose typical optical depth is \n\n\n\n\n\n, and the amount of the \n\n\n\n\n\n gas is underestimated by \n\n\n\n\n\n if a correction for the opacity effect is not applied. In Fukui et al. (2014, 2015), these analyses were made for the high Galactic latitude at \n\n\n\n\n\n where the gas density is low. An open issue discussed in Fukui et al. (2014, 2015) is if \n\n\n\n\n\n obeys a simple linear relationship with the \n\n\n\n\n\n or not. A study in the Orion A molecular cloud (Roy et al. 2013) indicates that the dust optical depth is proportional to the 1.28th power of \n\n\n\n\n\n, rather than a simple linear relation. If correct, this nonlinearity may be ascribed to the dust evolution at high column density. This suggests that it is possible to apply a minor modification of the method of Fukui et al. (2014, 2015) in order to improve the accuracy in \n\n\n\n\n\n.","Citation Text":["Gillmon et al. 2006"],"Citation Start End":[[1203,1222]]} {"Identifier":"2021ApJ...910...52C___2016_Instance_1","Paragraph":"Half a century ago, a series of theorems laid the ground for the Kerr hypothesis (Israel 1967; Carter 1971; Robinson 1975); according to these no-hair theorems, the only stationary, axisymmetric, asymptotically flat, regular outside of the horizon solution to four-dimensional GR when the matter fields feature the same isometries as the spacetime is the Kerr BH. Notwithstanding their significance, there are many ways with which to circumvent them and discover different solutions. Still, in four dimensions, hairy BHs have been described in different theories of gravity, such as Einstein–Yang–Mills (Bizon 1990; Künzle & Masood-ul-Alam 1990; Volkov & Galtsov 1990; Breitenlohner et al. 1992; Kleihaus & Kunz 1998, 2001; Kleihaus et al. 2004), scalar-tensor (Bocharova et al. 1970; Bekenstein 1974; Kleihaus et al. 2015; Collodel et al. 2020a), and Gauss–Bonnet theories (Kanti et al. 1996; Kleihaus et al. 2011, 2016; Antoniou et al. 2018; Doneva & Yazadjiev 2018; Silva et al. 2018; Cunha et al. 2019; Collodel et al. 2020b; Herdeiro et al. 2021; Berti et al. 2021). Remarkably, by dropping the assumption that the matter fields must be stationary and axisymmetric, Herdeiro and Radu found solutions in the context of GR where BHs have hair (Herdeiro & Radu 2014b, 2015), by minimally coupling to gravity a complex scalar field that depends on time and on the axial coordinate while its energy-momentum tensor still possesses the respective isometries; see Herdeiro et al. (2015, 2016a, 2016b), Brihaye et al. (2016), and Delgado et al. (2016) for generalizations. These are known as scalarized Kerr black holes (KBHsSH) and they are the object of study of this paper. In their domain of existence, they connect Kerr BHs (that is, with no hair) with pure solitonic solutions, also known as boson stars (BS), which are regular everywhere and feature no horizons. In this sense, one can think of the KBHsSH indeed as a combined system of a BS with a horizon at its center, and therefore it shares traits of both objects.","Citation Text":["Kleihaus et al.","2016"],"Citation Start End":[[894,909],[916,920]]} {"Identifier":"2021ApJ...910...52CIsrael_1967_Instance_1","Paragraph":"Half a century ago, a series of theorems laid the ground for the Kerr hypothesis (Israel 1967; Carter 1971; Robinson 1975); according to these no-hair theorems, the only stationary, axisymmetric, asymptotically flat, regular outside of the horizon solution to four-dimensional GR when the matter fields feature the same isometries as the spacetime is the Kerr BH. Notwithstanding their significance, there are many ways with which to circumvent them and discover different solutions. Still, in four dimensions, hairy BHs have been described in different theories of gravity, such as Einstein–Yang–Mills (Bizon 1990; Künzle & Masood-ul-Alam 1990; Volkov & Galtsov 1990; Breitenlohner et al. 1992; Kleihaus & Kunz 1998, 2001; Kleihaus et al. 2004), scalar-tensor (Bocharova et al. 1970; Bekenstein 1974; Kleihaus et al. 2015; Collodel et al. 2020a), and Gauss–Bonnet theories (Kanti et al. 1996; Kleihaus et al. 2011, 2016; Antoniou et al. 2018; Doneva & Yazadjiev 2018; Silva et al. 2018; Cunha et al. 2019; Collodel et al. 2020b; Herdeiro et al. 2021; Berti et al. 2021). Remarkably, by dropping the assumption that the matter fields must be stationary and axisymmetric, Herdeiro and Radu found solutions in the context of GR where BHs have hair (Herdeiro & Radu 2014b, 2015), by minimally coupling to gravity a complex scalar field that depends on time and on the axial coordinate while its energy-momentum tensor still possesses the respective isometries; see Herdeiro et al. (2015, 2016a, 2016b), Brihaye et al. (2016), and Delgado et al. (2016) for generalizations. These are known as scalarized Kerr black holes (KBHsSH) and they are the object of study of this paper. In their domain of existence, they connect Kerr BHs (that is, with no hair) with pure solitonic solutions, also known as boson stars (BS), which are regular everywhere and feature no horizons. In this sense, one can think of the KBHsSH indeed as a combined system of a BS with a horizon at its center, and therefore it shares traits of both objects.","Citation Text":["Israel 1967"],"Citation Start End":[[82,93]]} {"Identifier":"2021ApJ...910...52CHerdeiro_&_Radu_2014b_Instance_1","Paragraph":"Half a century ago, a series of theorems laid the ground for the Kerr hypothesis (Israel 1967; Carter 1971; Robinson 1975); according to these no-hair theorems, the only stationary, axisymmetric, asymptotically flat, regular outside of the horizon solution to four-dimensional GR when the matter fields feature the same isometries as the spacetime is the Kerr BH. Notwithstanding their significance, there are many ways with which to circumvent them and discover different solutions. Still, in four dimensions, hairy BHs have been described in different theories of gravity, such as Einstein–Yang–Mills (Bizon 1990; Künzle & Masood-ul-Alam 1990; Volkov & Galtsov 1990; Breitenlohner et al. 1992; Kleihaus & Kunz 1998, 2001; Kleihaus et al. 2004), scalar-tensor (Bocharova et al. 1970; Bekenstein 1974; Kleihaus et al. 2015; Collodel et al. 2020a), and Gauss–Bonnet theories (Kanti et al. 1996; Kleihaus et al. 2011, 2016; Antoniou et al. 2018; Doneva & Yazadjiev 2018; Silva et al. 2018; Cunha et al. 2019; Collodel et al. 2020b; Herdeiro et al. 2021; Berti et al. 2021). Remarkably, by dropping the assumption that the matter fields must be stationary and axisymmetric, Herdeiro and Radu found solutions in the context of GR where BHs have hair (Herdeiro & Radu 2014b, 2015), by minimally coupling to gravity a complex scalar field that depends on time and on the axial coordinate while its energy-momentum tensor still possesses the respective isometries; see Herdeiro et al. (2015, 2016a, 2016b), Brihaye et al. (2016), and Delgado et al. (2016) for generalizations. These are known as scalarized Kerr black holes (KBHsSH) and they are the object of study of this paper. In their domain of existence, they connect Kerr BHs (that is, with no hair) with pure solitonic solutions, also known as boson stars (BS), which are regular everywhere and feature no horizons. In this sense, one can think of the KBHsSH indeed as a combined system of a BS with a horizon at its center, and therefore it shares traits of both objects.","Citation Text":["Herdeiro & Radu 2014b"],"Citation Start End":[[1247,1268]]} {"Identifier":"2018ApJ...861...49H__Springob_et_al._2007_Instance_1","Paragraph":"Column 11.—Adopted distance DH and its uncertainty σD, both in Mpc. For objects with cz⊙ > 6000 \n\n\n\n\n\n, the distance is simply estimated as czcmb\/H, where czcmb is the recessional velocity measured in the cosmic microwave background reference frame (Lineweaver et al. 1996) and H is the Hubble constant, adopted to be 70 \n\n\n\n\n\n Mpc−1. For objects with czcmb 6000 \n\n\n\n\n\n, we use the local peculiar velocity model of Masters (2005), which is based in large part on the SFI++ catalog of galaxies (Springob et al. 2007) and results from analysis of the peculiar motions of galaxies, groups, and clusters using a combination of primary distances from the literature and secondary distances from the Tully–Fisher relation. The resulting model includes two attractors with infall onto the Virgo cluster and the Hydra-Centaurus supercluster, as well as a quadrupole and a dipole component. The transition from one distance estimation method to the other is selected to be at cz⊙ = 6000 \n\n\n\n\n\n because the uncertainties in each method become comparable at that distance. Where available, primary distances in the published literature are adopted; we also use secondary distances, mainly from Tully et al. (2013), for galaxies with czcmb 6000 \n\n\n\n\n\n. When the galaxy is a known member of a group (Springob et al. 2007), the group systemic recessional velocity czcmb is used to determine the distance estimate according to the general prescription just described. Where primary distances are not available, objects in the Virgo region are assigned to likely Virgo substructures (Mei et al. 2007), and then the distances to those subclusters are adopted following Hallenbeck et al. (2012). Errors on the distance are generated by running 1000 Monte Carlo iterations where peculiar velocities are drawn from a normal distribution each time, as described in Section 4.1 of Jones et al. (2018). Such errors are likely underestimates in the vicinity of major attractors such as Virgo. It should be noted that the values quoted here are Hubble distances, not comoving or luminosity distances.","Citation Text":["Springob et al. 2007"],"Citation Start End":[[495,515]]} {"Identifier":"2018ApJ...861...49H__Springob_et_al._2007_Instance_2","Paragraph":"Column 11.—Adopted distance DH and its uncertainty σD, both in Mpc. For objects with cz⊙ > 6000 \n\n\n\n\n\n, the distance is simply estimated as czcmb\/H, where czcmb is the recessional velocity measured in the cosmic microwave background reference frame (Lineweaver et al. 1996) and H is the Hubble constant, adopted to be 70 \n\n\n\n\n\n Mpc−1. For objects with czcmb 6000 \n\n\n\n\n\n, we use the local peculiar velocity model of Masters (2005), which is based in large part on the SFI++ catalog of galaxies (Springob et al. 2007) and results from analysis of the peculiar motions of galaxies, groups, and clusters using a combination of primary distances from the literature and secondary distances from the Tully–Fisher relation. The resulting model includes two attractors with infall onto the Virgo cluster and the Hydra-Centaurus supercluster, as well as a quadrupole and a dipole component. The transition from one distance estimation method to the other is selected to be at cz⊙ = 6000 \n\n\n\n\n\n because the uncertainties in each method become comparable at that distance. Where available, primary distances in the published literature are adopted; we also use secondary distances, mainly from Tully et al. (2013), for galaxies with czcmb 6000 \n\n\n\n\n\n. When the galaxy is a known member of a group (Springob et al. 2007), the group systemic recessional velocity czcmb is used to determine the distance estimate according to the general prescription just described. Where primary distances are not available, objects in the Virgo region are assigned to likely Virgo substructures (Mei et al. 2007), and then the distances to those subclusters are adopted following Hallenbeck et al. (2012). Errors on the distance are generated by running 1000 Monte Carlo iterations where peculiar velocities are drawn from a normal distribution each time, as described in Section 4.1 of Jones et al. (2018). Such errors are likely underestimates in the vicinity of major attractors such as Virgo. It should be noted that the values quoted here are Hubble distances, not comoving or luminosity distances.","Citation Text":["Springob et al. 2007"],"Citation Start End":[[1290,1310]]} {"Identifier":"2016MNRAS.461.2353N__Parker_1958_Instance_1","Paragraph":"The above formulation in principle applies to any planet with a Dungey cycle-type stellar wind–magnetosphere interaction, and we thus consider here the appropriate parameters for exoplanets orbiting at arbitrary distances, with an emphasis on close-orbiting hot Jupiters. As discussed above, whereas for the RBL the radio powers are computed as functions of incident kinetic or Poynting flux, in our model, the powers are principally functions of the motional electric field of the solar wind, the dynamic pressure of the stellar wind and the Pedersen conductance of the ionosphere, all of which are dependent on further stellar and planetary parameters as described below. We examine results for both a solar-like stellar wind, and that representative of a young Sun-like star with high-mass-loss rate and magnetic field strength relative to the Sun. Considering first the Sun-like stellar wind, the relevant parameters are shown in Fig. 4 versus radial distance d normalized by the solar radius Rs [we truncate the inner radial distance of the plot at 2 $\\mathrm{{\\rm {\\it R}}_s}$, being the canonical location of the heliospheric magnetic field ‘source surface’ (Owens & Forsyth 2013)]. Absolute distances in au are shown on the top axis for information, although we recognize that in reality the conversion from $\\mathrm{{\\rm {\\it R}}_s}$ to au depends on the individual star. Specifically, Fig. 4(a) shows with the solid line the incident velocity of the solar wind on the magnetosphere vm, which is a function both of the stellar wind speed and the planet's orbital speed. For simplicity, we employ Parker's isothermal solution for the stellar wind speed vsw (Parker 1958), which is fully parametrized by the sound speed cs, and which, as shown by Cranmer (2004) has the closed-form solution\n\n(18)\n\n\\begin{equation}\n{v_{{\\rm sw}}}^2= \\left\\lbrace \\begin{array}{@{}l@{\\quad }l@{}}-v_{\\rm c}^2W_0[-D(d)] & {\\rm if } d \\le d_{\\rm c} ,\\\\\n-v_{\\rm c}^2W_{-1}[-D(d)] & {\\rm if } d \\ge d_{\\rm c} ,\\\\\n\\end{array}\\right.\n\\end{equation}\n\nwhere W0 and W−1 are branches of the Lambert W function, dc is the critical distance at which vsw passes through the sound speed cs, given by\n\n(19)\n\n\\begin{equation}\nd_{\\rm c}=\\frac{GM_{\\rm s}}{2c_{\\rm s}^2},\n\\end{equation}\n\nwhere Ms = 1.9891 × 1030 kg is the solar mass and D(d) is given by\n\n(20)\n\n\\begin{equation}\nD(d)=\\left(\\frac{d}{d_{\\rm c}}\\right)^{-4}\\exp \\left[4 \\left(1-\\frac{d_{\\rm c}}{d}\\right)-1\\right].\n\\end{equation}\n\nFor the Sun-like wind, we employ a sound speed cs = 130 km s−1 (which, for a Sun-like average particle mass of 1.92 × 10−27 kg corresponds to a temperature of ∼1.18 MK, though note for the present Sun calculation we actually make no assumptions in this regard), yielding a velocity at 1 au of ∼480 km s−1, consistent with observations, and ∼50–200 km s−1 in the hot Jupiter region of 3–10 Rs (indicated by the grey region). The dotted line indicates the Keplerian speed of a planet in a circular orbit vorb, and the solid line is the sum in quadrature of the two, giving the resultant incident stellar wind speed vm. Note that the two speeds are comparable in the inner region associated with hot Jupiters, and although this will modify the orientation of the magnetosphere with respect to the radial vector, it will not significantly alter the magnetospheric dynamics. We further show with the loosely dotted and dot–dashed lines the (constant) sound speed cs and the Alfvén speed vA given by equation (5). It is evident that the interaction is everywhere supersonic (modestly so in the hot Jupiter region, with a Mach number of ∼2) but becomes sub-Alfvénic inside of ∼15 $\\mathrm{{\\rm {\\it R}}_S}$, such that Alfvén wings will form along the IMF field lines, as discussed by Saur et al. (2013), effectively shielding the stellar wind motional electric field and is related to KR saturation of the convection potential.","Citation Text":["Parker 1958"],"Citation Start End":[[1666,1677]]} {"Identifier":"2016ApJ...830...74A__late_1970s_Instance_1","Paragraph":"A simpler model with sinusoids only will be used when analyzing time series of activity indices. That is,\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\n\n\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n is some measurement of an activity index (e.g., emission in the \n\n\n\n\n\n line, S-index, etc.) obtained with instrument INS. The parentheses in \n\n\n\n\n\n mean that fits with and without long-term trends will also be investigated. The significance assessments here are performed using frequentist estimations of the false alarm probability (FAP) following the recipes by Baluev (2009). Detecting a periodic signal in a time series will consist of comparing a null model (e.g., no \n\n\n\n\n\n term) with a model with one more periodic signal (e.g., one sin\/cos term). Since the period is a highly nonlinear parameter, many periods (about 20,000 equally spaced in 1\/P or frequency domain) will be tested between 2 and 50,000 days. A plot of the improvement of the logarithm of the maximum likelihood statistic (\n\n\n\n\n\n) against the period of the test signal produces a plot that is often called a periodogram. Periodograms for unevenly sampled data were developed in the late 1970s (e.g., Lomb 1976; Scargle 1982). In those cases, the merit statistic plotted against the test period was the improvement in \n\n\n\n\n\n or the F-ratio statistic. These early methods only accounted for a model with a single sin\/cos component. A further refinement was later implemented by also including an offset (as our γ) as a free parameter to acknowledge the fact that the mean of the series was not known a priori. These periodograms were called floating mean periodograms (Ferraz-Mello 1981) or generalized least-squares (GLS, Zechmeister & Kürster 2009) periodograms. RRM15 relies on the use of GLS periodograms. GLS is adequate to identify and quantify the significance of periodicities if the data contain a single sinusoidal signal and uncertainties in the time series are realistic. Otherwise, analytic significance estimates of the favored solutions using GLS can only be considered to be approximate. In this sense, GLS is a very efficient method to guess the most likely signals left in residual data, but it cannot be used to provide a reliable assessment of its significance. This is discussed in the context of the basic model comparison in Anglada-Escudé & Tuomi (2015). Further refinements of the model (e.g., simultaneous fit to a trend, combining different instruments with different offsets, include basic models for unaccounted noise) require the use of more sophisticated tools beyond GLS, like the in-likelihood periodograms presented here. Note that the \n\n\n\n\n\n statistic used by GLS and previous periodograms is a particular case of the ln-likelihood statistic with \n\n\n\n\n\n, \n\n\n\n\n\n, and only one instrument INS. Finding the maximum likelihood statistic requires adjusting all of the free parameters of the model at each test period. For these reasons, it produces much more robust significance estimates than its predecessors, especially when the description of the data requires models more complex than a single sinusoid. Reviewing the properties of the likelihood function in the context of periodic signal detection is not the topic of this article. We refer the interested reader to Baluev (2009, 2013) for more detailed discussions and formal proofs.","Citation Text":["Lomb 1976"],"Citation Start End":[[1119,1128]]} {"Identifier":"2018AandA...617A...3L__Chandler_et_al._2005_Instance_1","Paragraph":"We stress the uncertainty of our present interpretation, given that the density and temperature structures of our target sources are not yet constrained in a sufficiently detailed way on our resolved spatial scales. In addition, our 44 GHz observationsare still subject to missing short-spacing, which nevertheless should not impact regions with high intensity. To provide a quantitative sense of how missing short-spacing biased the observed Stokes I intensity fractionally, we assume that exterior to the disks (or disk-like structures) around IRAS 16293–2422 A and B there is ~2 M⊙ of gas on ≳10′′ scales (Mundy et al. 1990), and assume that the gas to dust mass ratio is 100. The averaged dust mass column density is Σdust ~ 0.1 g cm−2. Assuming the dust opacity at 230 GHz is κ230 GHz = 0.5\n\n$^{0.5}_{-0.4}$−0.4+0.5\n cm2 g−1 (c.f., Draine 2006), and the dust opacity spectral index is β ~1−1.75 (Li et al. 2017), the derived averaged dust optical depth at 44 GHz is \n\n$\\tau_{\\mbox{\\tiny 44 GHz}}=\\kappa_{\\mbox{\\tiny 230 GHz}}(44\/230)^{\\beta}\\mathrm{\\Sigma}_{\\mbox{\\tiny dust}} = $τ 44 GHz=κ 230 GHz(44\/230)βΣ dust=\n2.8\n\n$^{16}_{-2.2}\\,\\times$−2.2+16 ×\n 10−3. Assuming a nominal 20–30 K dust temperature on 10′′ scales (van Dishoeck et al. 1995; Ceccarelli et al. 2000; Chandler et al. 2005), the brightness temperature of the extended dust emission is ~ (25 ± 5) × (1 − e−τ44 GHz) = 0.069\n\n$^{0.57}_{-0.058}$−0.058+0.57\n K. This is approximately how much missing short-spacing can bias the Stokes I intensity. If we take regions where the observed brightness temperature in the Robust = 0 weighted 44 GHz image is above 1.4 K (i.e., 6σ; the second contour from bottom in the right panel of Fig. 1) for example, missing flux can bias Stokes I intensity by at most ~(0.64 K)\/(1.4 K + 0.64 K) ~ 31%. For structures detected at the 6σ significance, clean errors and thermal noise (e.g., 3σ) may dominate the errors in the measured polarization percentages. The brightness temperature of the missing flux can be comparable with the 6σ detection limit of our Robust = 2 weighted 44 GHz image (~0.6 K), and therefore the observed polarization percentages can be biased by over ~50% in the low intensity (3–6σ) area in that image (Table B.1). Our assessment is that for our present 44 GHz images, missing short-spacing biased the observed polarization percentages of the detected, spatially-extended, dust emission component. Since the brightness temperature of the extended component is low (Fig. 1) such that dust is likely to be optically thin (i.e., Tbg = TCMB), missing short-spacing does not dramatically flip the observed polarization position angles by 90° (Sect. 4.1; Figs. 2–4).","Citation Text":["Chandler et al. 2005"],"Citation Start End":[[1274,1294]]} {"Identifier":"2020ApJ...900...70R__Lusso_et_al._2019_Instance_1","Paragraph":"In this work we first used the data points of low-redshift Hubble diagrams for Pantheons, quasars, and GRBs to put constraints on the present value of cosmographic parameters in an independent cosmography approach. To do this, we used different combinations of data samples including Pantheon, Pantheon + quasars, Pantheon + GRB, finally Pantheon + quasars + GRB. In the context of a cosmography approach, we obtained the best-fit values of cosmographic parameters as well as their confidence regions up to 3 − σ uncertainties for different combinations of data samples. Our results showed that the best-fit value of the deceleration parameter q0 varies in the range of −0.844 to −0.702 and the best fit of jerk parameter j0 varies in the range of 1.60 to 2.61 for different combinations of data samples. Note that here we used the Hubble diagrams of quasars and GRBs, respectively, derived in Lusso & Risaliti (2016a) and Demianski et al. (2017a). In the calibration procedure to form the Hubble diagrams of both quasars and GRBs, they have used the SNIa data at low redshifts. Their results for quasars and GRBs samples are consistent with that of the SNIa samples at the low-redshift universe. Hence we adopted their calibrations and used their Hubble diagrams for quasars and GRBs. In the case of concordance ΛCDM cosmology, our results are also compatible with recent work in Lusso et al. (2019). They confirmed the presence of a tension between Λ cosmology and the best-fit cosmographic parameters ∼4σ with SnIa+quasars, at ∼2σ with SnIa+GRBs, and at 4σ with the whole SnIa+quasars+GRB data set (Lusso et al. 2019). Furthermore, we studied some relevant DE parameterizations as well as the concordance ΛCDM cosmology using the Hubble diagrams of Pantheons, quasars, and GRB observations in the context of a cosmography approach. The DE parameterizations studied in our analysis are wCDM, CPL, and Pade parameterizations. First, using the different combinations of data samples and in the context of the MCMC algorithm, we calculate the χ2 function of the distance modulus to find the best-fit values and also the 1 − σ uncertainty of cosmological parameters for each DE parameterization. Using the chain of data obtained for cosmological parameters, we found the best-fit values and the 1 − σ confidence region of the cosmographic parameters of DE parameterizations. Comparing the results for DE models with those obtained for the model-independent approach leads us to conclude that the model is in better (worse) agreement with Hubble diagrams of Pantheons, quasars, and GRBs. In the first stage, using the solely Pantheon sample, we found that the wCDM model is the most compatible model with the result of model-independent constraints and on the other hand the concordance ΛCDM model is the worst model. In the second step, by combining the GRB data to the Pantheon sample, we obtained disappointing results for the ΛCDM model. In this case the q0 parameter of the ΛCDM has a 3.8 − σ tension with that of the model-independent cosmography approach. Moreover, the j0 parameter of ΛCDM cosmology has roughly 5 − σ tension with that of the model-independent approach. These results will be more complicated when we see the results of other DE models and parameterizations that we studied in this work. We observed that wCDM, CPL, and Pade parameterizations are in better agreement with the results of the model-independent cosmography approach rather than the concordance model. In the third and fourth steps, using the combinations Pantheon+quasars and Pantheon+GRB+quasars data points, we obtained the same results again, supporting our results in previous steps. So we conclude that the concordance ΛCDM cosmology has much tension with observations of quasars and GRBs at higher redshift. Note that the DE parameterizations studied in this work are in better agreement with Hubble diagrams of high-redshift quasars and GRB observations. Finally, we reconstructed the Hubble parameter using the best-fit value of cosmographic parameters for both model-independent approaches, the ΛCDM model, and DE parameterizations. We observed that for different data sample combinations, the evolution of reconstructed H(z) in a concordance ΛCDM model has a maximum deviation from the confidence region compared to different DE parameterizations. Upon this result, we can conclude that among the different cosmological models studied in this work, the ΛCDM has the minimum compatibility with the predictions of a model-independent approach and thus it is falsified by a cosmography approach. The large value of tensions (between 3σ to 6σ for different data combinations) that we observed between the cosmographic parameters of ΛCDM and those we obtained in the model-independent approach support this claim again that we should explore other alternatives for standard ΛCDM cosmology. We observed that other DE parameterizations in this study cannot be refuted in the context of a cosmography approach. Our results for ΛCDM cosmology are in agreement with the results of recent work (Yang et al. 2019; Khadka & Ratra 2020), which were obtained using a different approach and different data sets. Although in the literature it has been thoroughly affirmed that the ΛCDM describes the evolution of the universe until recent times, our conclusion confirms the result of Benetti & Capozziello (2019) that show large tensions emerge at higher redshifts for ΛCDM. Our analysis can be extended by considering other cosmic observations in the context of a cosmography approach.","Citation Text":["Lusso et al. (2019)"],"Citation Start End":[[1381,1400]]} {"Identifier":"2020ApJ...900...70R__Lusso_et_al._2019_Instance_2","Paragraph":"In this work we first used the data points of low-redshift Hubble diagrams for Pantheons, quasars, and GRBs to put constraints on the present value of cosmographic parameters in an independent cosmography approach. To do this, we used different combinations of data samples including Pantheon, Pantheon + quasars, Pantheon + GRB, finally Pantheon + quasars + GRB. In the context of a cosmography approach, we obtained the best-fit values of cosmographic parameters as well as their confidence regions up to 3 − σ uncertainties for different combinations of data samples. Our results showed that the best-fit value of the deceleration parameter q0 varies in the range of −0.844 to −0.702 and the best fit of jerk parameter j0 varies in the range of 1.60 to 2.61 for different combinations of data samples. Note that here we used the Hubble diagrams of quasars and GRBs, respectively, derived in Lusso & Risaliti (2016a) and Demianski et al. (2017a). In the calibration procedure to form the Hubble diagrams of both quasars and GRBs, they have used the SNIa data at low redshifts. Their results for quasars and GRBs samples are consistent with that of the SNIa samples at the low-redshift universe. Hence we adopted their calibrations and used their Hubble diagrams for quasars and GRBs. In the case of concordance ΛCDM cosmology, our results are also compatible with recent work in Lusso et al. (2019). They confirmed the presence of a tension between Λ cosmology and the best-fit cosmographic parameters ∼4σ with SnIa+quasars, at ∼2σ with SnIa+GRBs, and at 4σ with the whole SnIa+quasars+GRB data set (Lusso et al. 2019). Furthermore, we studied some relevant DE parameterizations as well as the concordance ΛCDM cosmology using the Hubble diagrams of Pantheons, quasars, and GRB observations in the context of a cosmography approach. The DE parameterizations studied in our analysis are wCDM, CPL, and Pade parameterizations. First, using the different combinations of data samples and in the context of the MCMC algorithm, we calculate the χ2 function of the distance modulus to find the best-fit values and also the 1 − σ uncertainty of cosmological parameters for each DE parameterization. Using the chain of data obtained for cosmological parameters, we found the best-fit values and the 1 − σ confidence region of the cosmographic parameters of DE parameterizations. Comparing the results for DE models with those obtained for the model-independent approach leads us to conclude that the model is in better (worse) agreement with Hubble diagrams of Pantheons, quasars, and GRBs. In the first stage, using the solely Pantheon sample, we found that the wCDM model is the most compatible model with the result of model-independent constraints and on the other hand the concordance ΛCDM model is the worst model. In the second step, by combining the GRB data to the Pantheon sample, we obtained disappointing results for the ΛCDM model. In this case the q0 parameter of the ΛCDM has a 3.8 − σ tension with that of the model-independent cosmography approach. Moreover, the j0 parameter of ΛCDM cosmology has roughly 5 − σ tension with that of the model-independent approach. These results will be more complicated when we see the results of other DE models and parameterizations that we studied in this work. We observed that wCDM, CPL, and Pade parameterizations are in better agreement with the results of the model-independent cosmography approach rather than the concordance model. In the third and fourth steps, using the combinations Pantheon+quasars and Pantheon+GRB+quasars data points, we obtained the same results again, supporting our results in previous steps. So we conclude that the concordance ΛCDM cosmology has much tension with observations of quasars and GRBs at higher redshift. Note that the DE parameterizations studied in this work are in better agreement with Hubble diagrams of high-redshift quasars and GRB observations. Finally, we reconstructed the Hubble parameter using the best-fit value of cosmographic parameters for both model-independent approaches, the ΛCDM model, and DE parameterizations. We observed that for different data sample combinations, the evolution of reconstructed H(z) in a concordance ΛCDM model has a maximum deviation from the confidence region compared to different DE parameterizations. Upon this result, we can conclude that among the different cosmological models studied in this work, the ΛCDM has the minimum compatibility with the predictions of a model-independent approach and thus it is falsified by a cosmography approach. The large value of tensions (between 3σ to 6σ for different data combinations) that we observed between the cosmographic parameters of ΛCDM and those we obtained in the model-independent approach support this claim again that we should explore other alternatives for standard ΛCDM cosmology. We observed that other DE parameterizations in this study cannot be refuted in the context of a cosmography approach. Our results for ΛCDM cosmology are in agreement with the results of recent work (Yang et al. 2019; Khadka & Ratra 2020), which were obtained using a different approach and different data sets. Although in the literature it has been thoroughly affirmed that the ΛCDM describes the evolution of the universe until recent times, our conclusion confirms the result of Benetti & Capozziello (2019) that show large tensions emerge at higher redshifts for ΛCDM. Our analysis can be extended by considering other cosmic observations in the context of a cosmography approach.","Citation Text":["Lusso et al. 2019"],"Citation Start End":[[1603,1620]]} {"Identifier":"2020ApJ...900...70RDemianski_et_al._(2017a)_Instance_1","Paragraph":"In this work we first used the data points of low-redshift Hubble diagrams for Pantheons, quasars, and GRBs to put constraints on the present value of cosmographic parameters in an independent cosmography approach. To do this, we used different combinations of data samples including Pantheon, Pantheon + quasars, Pantheon + GRB, finally Pantheon + quasars + GRB. In the context of a cosmography approach, we obtained the best-fit values of cosmographic parameters as well as their confidence regions up to 3 − σ uncertainties for different combinations of data samples. Our results showed that the best-fit value of the deceleration parameter q0 varies in the range of −0.844 to −0.702 and the best fit of jerk parameter j0 varies in the range of 1.60 to 2.61 for different combinations of data samples. Note that here we used the Hubble diagrams of quasars and GRBs, respectively, derived in Lusso & Risaliti (2016a) and Demianski et al. (2017a). In the calibration procedure to form the Hubble diagrams of both quasars and GRBs, they have used the SNIa data at low redshifts. Their results for quasars and GRBs samples are consistent with that of the SNIa samples at the low-redshift universe. Hence we adopted their calibrations and used their Hubble diagrams for quasars and GRBs. In the case of concordance ΛCDM cosmology, our results are also compatible with recent work in Lusso et al. (2019). They confirmed the presence of a tension between Λ cosmology and the best-fit cosmographic parameters ∼4σ with SnIa+quasars, at ∼2σ with SnIa+GRBs, and at 4σ with the whole SnIa+quasars+GRB data set (Lusso et al. 2019). Furthermore, we studied some relevant DE parameterizations as well as the concordance ΛCDM cosmology using the Hubble diagrams of Pantheons, quasars, and GRB observations in the context of a cosmography approach. The DE parameterizations studied in our analysis are wCDM, CPL, and Pade parameterizations. First, using the different combinations of data samples and in the context of the MCMC algorithm, we calculate the χ2 function of the distance modulus to find the best-fit values and also the 1 − σ uncertainty of cosmological parameters for each DE parameterization. Using the chain of data obtained for cosmological parameters, we found the best-fit values and the 1 − σ confidence region of the cosmographic parameters of DE parameterizations. Comparing the results for DE models with those obtained for the model-independent approach leads us to conclude that the model is in better (worse) agreement with Hubble diagrams of Pantheons, quasars, and GRBs. In the first stage, using the solely Pantheon sample, we found that the wCDM model is the most compatible model with the result of model-independent constraints and on the other hand the concordance ΛCDM model is the worst model. In the second step, by combining the GRB data to the Pantheon sample, we obtained disappointing results for the ΛCDM model. In this case the q0 parameter of the ΛCDM has a 3.8 − σ tension with that of the model-independent cosmography approach. Moreover, the j0 parameter of ΛCDM cosmology has roughly 5 − σ tension with that of the model-independent approach. These results will be more complicated when we see the results of other DE models and parameterizations that we studied in this work. We observed that wCDM, CPL, and Pade parameterizations are in better agreement with the results of the model-independent cosmography approach rather than the concordance model. In the third and fourth steps, using the combinations Pantheon+quasars and Pantheon+GRB+quasars data points, we obtained the same results again, supporting our results in previous steps. So we conclude that the concordance ΛCDM cosmology has much tension with observations of quasars and GRBs at higher redshift. Note that the DE parameterizations studied in this work are in better agreement with Hubble diagrams of high-redshift quasars and GRB observations. Finally, we reconstructed the Hubble parameter using the best-fit value of cosmographic parameters for both model-independent approaches, the ΛCDM model, and DE parameterizations. We observed that for different data sample combinations, the evolution of reconstructed H(z) in a concordance ΛCDM model has a maximum deviation from the confidence region compared to different DE parameterizations. Upon this result, we can conclude that among the different cosmological models studied in this work, the ΛCDM has the minimum compatibility with the predictions of a model-independent approach and thus it is falsified by a cosmography approach. The large value of tensions (between 3σ to 6σ for different data combinations) that we observed between the cosmographic parameters of ΛCDM and those we obtained in the model-independent approach support this claim again that we should explore other alternatives for standard ΛCDM cosmology. We observed that other DE parameterizations in this study cannot be refuted in the context of a cosmography approach. Our results for ΛCDM cosmology are in agreement with the results of recent work (Yang et al. 2019; Khadka & Ratra 2020), which were obtained using a different approach and different data sets. Although in the literature it has been thoroughly affirmed that the ΛCDM describes the evolution of the universe until recent times, our conclusion confirms the result of Benetti & Capozziello (2019) that show large tensions emerge at higher redshifts for ΛCDM. Our analysis can be extended by considering other cosmic observations in the context of a cosmography approach.","Citation Text":["Demianski et al. (2017a)"],"Citation Start End":[[923,947]]} {"Identifier":"2020ApJ...900...70RYang_et_al._2019_Instance_1","Paragraph":"In this work we first used the data points of low-redshift Hubble diagrams for Pantheons, quasars, and GRBs to put constraints on the present value of cosmographic parameters in an independent cosmography approach. To do this, we used different combinations of data samples including Pantheon, Pantheon + quasars, Pantheon + GRB, finally Pantheon + quasars + GRB. In the context of a cosmography approach, we obtained the best-fit values of cosmographic parameters as well as their confidence regions up to 3 − σ uncertainties for different combinations of data samples. Our results showed that the best-fit value of the deceleration parameter q0 varies in the range of −0.844 to −0.702 and the best fit of jerk parameter j0 varies in the range of 1.60 to 2.61 for different combinations of data samples. Note that here we used the Hubble diagrams of quasars and GRBs, respectively, derived in Lusso & Risaliti (2016a) and Demianski et al. (2017a). In the calibration procedure to form the Hubble diagrams of both quasars and GRBs, they have used the SNIa data at low redshifts. Their results for quasars and GRBs samples are consistent with that of the SNIa samples at the low-redshift universe. Hence we adopted their calibrations and used their Hubble diagrams for quasars and GRBs. In the case of concordance ΛCDM cosmology, our results are also compatible with recent work in Lusso et al. (2019). They confirmed the presence of a tension between Λ cosmology and the best-fit cosmographic parameters ∼4σ with SnIa+quasars, at ∼2σ with SnIa+GRBs, and at 4σ with the whole SnIa+quasars+GRB data set (Lusso et al. 2019). Furthermore, we studied some relevant DE parameterizations as well as the concordance ΛCDM cosmology using the Hubble diagrams of Pantheons, quasars, and GRB observations in the context of a cosmography approach. The DE parameterizations studied in our analysis are wCDM, CPL, and Pade parameterizations. First, using the different combinations of data samples and in the context of the MCMC algorithm, we calculate the χ2 function of the distance modulus to find the best-fit values and also the 1 − σ uncertainty of cosmological parameters for each DE parameterization. Using the chain of data obtained for cosmological parameters, we found the best-fit values and the 1 − σ confidence region of the cosmographic parameters of DE parameterizations. Comparing the results for DE models with those obtained for the model-independent approach leads us to conclude that the model is in better (worse) agreement with Hubble diagrams of Pantheons, quasars, and GRBs. In the first stage, using the solely Pantheon sample, we found that the wCDM model is the most compatible model with the result of model-independent constraints and on the other hand the concordance ΛCDM model is the worst model. In the second step, by combining the GRB data to the Pantheon sample, we obtained disappointing results for the ΛCDM model. In this case the q0 parameter of the ΛCDM has a 3.8 − σ tension with that of the model-independent cosmography approach. Moreover, the j0 parameter of ΛCDM cosmology has roughly 5 − σ tension with that of the model-independent approach. These results will be more complicated when we see the results of other DE models and parameterizations that we studied in this work. We observed that wCDM, CPL, and Pade parameterizations are in better agreement with the results of the model-independent cosmography approach rather than the concordance model. In the third and fourth steps, using the combinations Pantheon+quasars and Pantheon+GRB+quasars data points, we obtained the same results again, supporting our results in previous steps. So we conclude that the concordance ΛCDM cosmology has much tension with observations of quasars and GRBs at higher redshift. Note that the DE parameterizations studied in this work are in better agreement with Hubble diagrams of high-redshift quasars and GRB observations. Finally, we reconstructed the Hubble parameter using the best-fit value of cosmographic parameters for both model-independent approaches, the ΛCDM model, and DE parameterizations. We observed that for different data sample combinations, the evolution of reconstructed H(z) in a concordance ΛCDM model has a maximum deviation from the confidence region compared to different DE parameterizations. Upon this result, we can conclude that among the different cosmological models studied in this work, the ΛCDM has the minimum compatibility with the predictions of a model-independent approach and thus it is falsified by a cosmography approach. The large value of tensions (between 3σ to 6σ for different data combinations) that we observed between the cosmographic parameters of ΛCDM and those we obtained in the model-independent approach support this claim again that we should explore other alternatives for standard ΛCDM cosmology. We observed that other DE parameterizations in this study cannot be refuted in the context of a cosmography approach. Our results for ΛCDM cosmology are in agreement with the results of recent work (Yang et al. 2019; Khadka & Ratra 2020), which were obtained using a different approach and different data sets. Although in the literature it has been thoroughly affirmed that the ΛCDM describes the evolution of the universe until recent times, our conclusion confirms the result of Benetti & Capozziello (2019) that show large tensions emerge at higher redshifts for ΛCDM. Our analysis can be extended by considering other cosmic observations in the context of a cosmography approach.","Citation Text":["Yang et al. 2019"],"Citation Start End":[[5081,5097]]} {"Identifier":"2020ApJ...900...70RBenetti_&_Capozziello_(2019)_Instance_1","Paragraph":"In this work we first used the data points of low-redshift Hubble diagrams for Pantheons, quasars, and GRBs to put constraints on the present value of cosmographic parameters in an independent cosmography approach. To do this, we used different combinations of data samples including Pantheon, Pantheon + quasars, Pantheon + GRB, finally Pantheon + quasars + GRB. In the context of a cosmography approach, we obtained the best-fit values of cosmographic parameters as well as their confidence regions up to 3 − σ uncertainties for different combinations of data samples. Our results showed that the best-fit value of the deceleration parameter q0 varies in the range of −0.844 to −0.702 and the best fit of jerk parameter j0 varies in the range of 1.60 to 2.61 for different combinations of data samples. Note that here we used the Hubble diagrams of quasars and GRBs, respectively, derived in Lusso & Risaliti (2016a) and Demianski et al. (2017a). In the calibration procedure to form the Hubble diagrams of both quasars and GRBs, they have used the SNIa data at low redshifts. Their results for quasars and GRBs samples are consistent with that of the SNIa samples at the low-redshift universe. Hence we adopted their calibrations and used their Hubble diagrams for quasars and GRBs. In the case of concordance ΛCDM cosmology, our results are also compatible with recent work in Lusso et al. (2019). They confirmed the presence of a tension between Λ cosmology and the best-fit cosmographic parameters ∼4σ with SnIa+quasars, at ∼2σ with SnIa+GRBs, and at 4σ with the whole SnIa+quasars+GRB data set (Lusso et al. 2019). Furthermore, we studied some relevant DE parameterizations as well as the concordance ΛCDM cosmology using the Hubble diagrams of Pantheons, quasars, and GRB observations in the context of a cosmography approach. The DE parameterizations studied in our analysis are wCDM, CPL, and Pade parameterizations. First, using the different combinations of data samples and in the context of the MCMC algorithm, we calculate the χ2 function of the distance modulus to find the best-fit values and also the 1 − σ uncertainty of cosmological parameters for each DE parameterization. Using the chain of data obtained for cosmological parameters, we found the best-fit values and the 1 − σ confidence region of the cosmographic parameters of DE parameterizations. Comparing the results for DE models with those obtained for the model-independent approach leads us to conclude that the model is in better (worse) agreement with Hubble diagrams of Pantheons, quasars, and GRBs. In the first stage, using the solely Pantheon sample, we found that the wCDM model is the most compatible model with the result of model-independent constraints and on the other hand the concordance ΛCDM model is the worst model. In the second step, by combining the GRB data to the Pantheon sample, we obtained disappointing results for the ΛCDM model. In this case the q0 parameter of the ΛCDM has a 3.8 − σ tension with that of the model-independent cosmography approach. Moreover, the j0 parameter of ΛCDM cosmology has roughly 5 − σ tension with that of the model-independent approach. These results will be more complicated when we see the results of other DE models and parameterizations that we studied in this work. We observed that wCDM, CPL, and Pade parameterizations are in better agreement with the results of the model-independent cosmography approach rather than the concordance model. In the third and fourth steps, using the combinations Pantheon+quasars and Pantheon+GRB+quasars data points, we obtained the same results again, supporting our results in previous steps. So we conclude that the concordance ΛCDM cosmology has much tension with observations of quasars and GRBs at higher redshift. Note that the DE parameterizations studied in this work are in better agreement with Hubble diagrams of high-redshift quasars and GRB observations. Finally, we reconstructed the Hubble parameter using the best-fit value of cosmographic parameters for both model-independent approaches, the ΛCDM model, and DE parameterizations. We observed that for different data sample combinations, the evolution of reconstructed H(z) in a concordance ΛCDM model has a maximum deviation from the confidence region compared to different DE parameterizations. Upon this result, we can conclude that among the different cosmological models studied in this work, the ΛCDM has the minimum compatibility with the predictions of a model-independent approach and thus it is falsified by a cosmography approach. The large value of tensions (between 3σ to 6σ for different data combinations) that we observed between the cosmographic parameters of ΛCDM and those we obtained in the model-independent approach support this claim again that we should explore other alternatives for standard ΛCDM cosmology. We observed that other DE parameterizations in this study cannot be refuted in the context of a cosmography approach. Our results for ΛCDM cosmology are in agreement with the results of recent work (Yang et al. 2019; Khadka & Ratra 2020), which were obtained using a different approach and different data sets. Although in the literature it has been thoroughly affirmed that the ΛCDM describes the evolution of the universe until recent times, our conclusion confirms the result of Benetti & Capozziello (2019) that show large tensions emerge at higher redshifts for ΛCDM. Our analysis can be extended by considering other cosmic observations in the context of a cosmography approach.","Citation Text":["Benetti & Capozziello (2019)"],"Citation Start End":[[5364,5392]]} {"Identifier":"2020MNRAS.496.2849P__Mutter_et_al._2017_Instance_1","Paragraph":"To definitively assess whether or not the growth of the vertical kinetic energy observed in our simulations is associated with the disc eccentricity, we performed three additional simulations using the parameters of the fiducial model, except that: (i) In the first simulation, the disc orbits a single star and the cooling time-scale is set to tc = 0.1Ω−1; (ii) In a second run, the disc orbits a single star and the cooling time-scale is set to tc = 0.001Ω−1; and (iii) In the third run, we restarted the fiducial model at time t0 = 955 but with the system slowly transitioning from a central binary system into a single star located at the centre of mass. This is done by treating the gravitational potential as the sum of two terms, one corresponding to the binary plus one corresponding to a single star, with weighting factors that change with time. More precisely, the gravitational potential for this simulation is given by (Mutter et al. 2017)\n(23)$$\\begin{eqnarray}\r\n\\Phi _{\\rm trans}=(1-W (t))\\Phi _{\\rm bin}-\\frac{GM_\\star }{r} W(t)\r\n\\end{eqnarray}$$with\n(24)$$\\begin{eqnarray}\r\nW(t) &= \\left\\lbrace \\begin{array}{@{}l@{\\quad }l@{}}1 & \\text{if } \\,\\, t-t_0 \\ge 100T_{\\rm bin}\\\\\r\n\\frac{1}{2}\\left[1-\\cos \\left(\\frac{\\pi (t-t_0)}{100T_{\\rm bin}}\\right) \\right] & \\text{if} \\,\\, t-t_0 \\lt 100T_{\\rm bin}\\end{array}.\\right.\r\n\\end{eqnarray}$$The aim of simulations (i) and (ii) is to check that our fiducial disc is stable to the VSI whereas run (iii) is useful to examine whether the turbulent flow is maintained under unforced conditions. For these three calculations, the time evolution of the vertical kinetic energy is shown in Fig. 5. Considering simulations (i) and (ii), exponential growth of the vertical kinetic energy due to growth of the VSI only occurs for the case with tc = 0.001 Ω−1. This is consistent with the results of Richard, Nelson & Umurhan (2016), who found that for h = 0.05 the disc remains stable to the VSI provided tc > 0.05 Ω−1. It also demonstrates that our fiducial model, which has tc = Ω−1, is stable to the VSI. For simulation (iii), the saturation level of the vertical kinetic energy remains essentially unchanged after the switch (t = 1055). Contours of the normalized density perturbation one scale height above the mid-plane, and of the meridional velocity in a [R, Z] plane located at azimuth φ = π, are presented in Fig. 6 at t = 1500. They clearly reveal that both the eccentric mode and the turbulence can be maintained under unforced conditions. The continued existence of the eccentric mode at that time is not surprising since m = 1 free eccentric modes can be long lived (Papaloizou 2005b). The persistence of the turbulent flow is a strong indication that the instability originates from the presence of an eccentric mode in the disc.","Citation Text":["Mutter et al. 2017"],"Citation Start End":[[933,951]]} {"Identifier":"2020ApJ...905...35K__Li_et_al._2015_Instance_1","Paragraph":"Another, probably more plausible, explanation for the systematic trend in Figure 5 might be that, in deriving SN explosion energy from the global parameters, it is difficult to take into account the complex environments of SNRs, and this is compounded by the parameter sensitivity of Equation (10) (and to a lesser extent, Equation (8)). As we have already seen in many observed SNRs (e.g., Figure 1) and simulated SNRs (e.g., Figure 3), the real ISM provides a very complex environment for SNRs. In this case, the background medium density parameter \n\n\n\n\n\n for describing SNR evolution is not well-defined. Fortunately, as demonstrated in 3D simulations considering inhomogeneous background medium (e.g., Figure 4; see also Cho et al. 2015; Iffrig & Hennebelle 2015; Kim & Ostriker 2015; Li et al. 2015; Martizzi et al. 2015; Walch & Naab 2015; Zhang & Chevalier 2019), the evolutionary tracks of integrated quantities such as total momentum and kinetic energy in the radiative SNRs (i.e., after the shell formation) are not sensitive to the complexity of the background medium. In particular, the total momentum does not evolve in time after reaching a terminal value. The model uncertainty due to the ISM inhomogeneity is less than a factor of two. However, a unitary background medium density \n\n\n\n\n\n does not seem be applicable to both \n\n\n\n\n\n and \n\n\n\n\n\n. In our TS models, where the ambient medium has a large-scale nonuniformity, the thermal energy is considerably smaller than that of the uniform medium case with the same mean density (Figure 4(e)). This also happens for some SNRs in TI models (see Section 4.2). On the other hand, the observed thermal energies of the SNRs appear to be generally larger than those of the uniform medium cases with the same mean densities (Figure 4(f)). For the two prototypical SNRs interacting with MCs, W44 and IC 443, for example, Table 5 shows that \n\n\n\n\n\n\/\n\n\n\n\n\n = 6–8 when we adopt the mean ambient density \n\n\n\n\n\n(H i+H2)(=50–70 cm−3). It is, however, clear that this density is much higher than the density of the material filling most of the volume of the ISM where the SN blast wave propagates. For example, the ambient density derived from an analysis of the X-ray surface brightness profile of W44 is ∼3 cm−3 (Harrus et al. 1997). An overestimated ambient density would predict a smaller \n\n\n\n\n\n or a larger \n\n\n\n\n\n to match the observed \n\n\n\n\n\n (see Equation (10)). On the other hand, Equation (10) is based on 1D simulations. In real SNRs in inhomogeneous\/nonuniform media, the cooling could be significantly enhanced due to the mixing and diffusion between the engulfed dense material and the hot plasma, in which case the thermal energy of real SNRs might be smaller than the \n\n\n\n\n\n predicted from 1D simulations. Therefore, it is not obvious whether Equation (10) with \n\n\n\n\n\n(H i+H2) would overpredict or underpredict \n\n\n\n\n\n for SNRs in complex environments (see also Section 4.2). High-resolution simulations of SNRs in realistic environments, including the complex physics at the hot\/cool interface, are needed in oder to understand the environmental dependency of the evolution of thermal energy.","Citation Text":["Li et al. 2015"],"Citation Start End":[[789,803]]} {"Identifier":"2022AandARv..30....6M__Mauch_and_Sadler_2007_Instance_1","Paragraph":"It has been clear since many years now (Matthews et al. 1964) that the majority of powerful radio-AGN is hosted within the most massive galaxies (stellar masses M∗∼1011M⊙\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$M_* \\sim 10^{11}\\, M_\\odot$$\\end{document} and above) known in the universe. This result has been confirmed at least up to z∼1\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$z\\sim 1$$\\end{document} (and in some cases beyond) both by direct estimates (e.g., Heeschen 1970; Ekers and Ekers 1973; Auriemma et al. 1977; Jenkins 1982; Best et al. 2005a; Mauch and Sadler 2007; Smolčić et al. 2009; Magliocchetti et al. 2016; Sabater et al. 2019; Capetti et al. 2022) and also by the extremely tight correlation in the MK-z\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$M_K-z$$\\end{document} plane exhibited by the hosts of radio-AGN (e.g., Lilly and Longair 1984; Eales et al. 1997; Jarvis et al. 2001; De Breuck et al. 2002; Willott et al. 2003) that can be explained by assuming that the observed K-band light is dominated by emission from the old stellar population and that radio-AGN have very similar (large) host masses all across half of the age of the universe. More recent results based on rest-frame 1.6 and 4.5 μ\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$\\upmu$$\\end{document}m photometry also report very high masses for the hosts of radio-AGN, at least up to z∼3\\documentclass[12pt]{minimal}\n\t\t\t\t\\usepackage{amsmath}\n\t\t\t\t\\usepackage{wasysym}\n\t\t\t\t\\usepackage{amsfonts}\n\t\t\t\t\\usepackage{amssymb}\n\t\t\t\t\\usepackage{amsbsy}\n\t\t\t\t\\usepackage{mathrsfs}\n\t\t\t\t\\usepackage{upgreek}\n\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\n\t\t\t\t\\begin{document}$$z\\sim 3$$\\end{document} if not beyond (Seymour et al. 2007; De Breuck et al. 2010; Gürkan et al. 2014; Drouart et al. 2016).\n","Citation Text":["Mauch and Sadler 2007"],"Citation Start End":[[1003,1024]]} {"Identifier":"2017ApJ...849...56A__Tamura_et_al._1996_Instance_1","Paragraph":"On a ∼30000 au scale, a bipolar outflow associated with this source was detected in the east-west direction by FCRAO single-dish observations in 12CO \n\n\n\n\nJ\n=\n1\n−\n0\n\n\n molecular line emission (Narayanan et al. 2012) and by James Clerk Maxwell Telescope (JCMT) single-dish observations in 12CO \n\n\n\n\nJ\n=\n3\n−\n2\n\n\n molecular line emission (Hogerheijde et al. 1998). Their results show that the blue and red robes of the outflows are on the eastern and western sides, respectively. On the other hand, inner parts (∼8000 au scale) of the outflow mapped with the Nobeyama Millimeter Array (NMA) in 12CO \n\n\n\n\nJ\n=\n1\n−\n0\n\n\n show the opposite distribution, i.e., stronger blueshifted emission on the western side and stronger redshifted emission on the eastern side (Tamura et al. 1996). Mid-infrared observations toward L1527 IRS with Spitzer Space Telescope shows bright bipolar scattered light nebulae along the outflow axis in the ∼20000 au scale (Tobin et al. 2008). They fitted a protostellar envelope model to near- and mid-infrared scattered light images and spectral energy distribution (SED). As a result, the inclination angle of the envelope around L1527 IRS was estimated to be \n\n\n\n\ni\n=\n85\n°\n\n\n, where \n\n\n\n\ni\n=\n90\n°\n\n\n is the edge-on configuration. In addition, Oya et al. (2015) found that the western side is closer to observers. This inclination angle is consistent with a disk-like structure of dust highly elongated along the north-south direction, which was spatially resolved for the first time in 7-mm continuum emission by the Very Large Array (VLA; Loinard et al. 2002). By expanding the studies by Tobin et al. (2008, 2013), we fitted a model composed of an envelope and a disk to (sub)millimeter continuum emissions and visibilities observed with the Submillimeter Array (SMA) and the Combined Array for Research in Millimeter Astronomy (CARMA), as well as infrared images and SED. Their best-fitting model suggests a highly flared disk structure (\n\n\n\n\nH\n∝\n\n\nR\n\n\n1.3\n\n\n\n\n, H = 48 au at R = 100 au) with a radius of 125 au. This study has geometrically distinguished the protostellar disk and envelope around L1527 IRS, although they were not kinematically distinguished from one another.","Citation Text":["Tamura et al. 1996"],"Citation Start End":[[756,774]]} {"Identifier":"2019AandA...628A..17W__Keeton_2003_Instance_1","Paragraph":"The error budget associated with Δtij was estimated by considering three sources of uncertainties. Firstly, we propagated the statistical error inferred from the MCMC sampling. This was simply done by constructing histograms for Δtij h−1 from the independent samples of SIEg model parameters reported in Figs. 3 and 4. An example of these histograms is illustrated in Fig. 7 for the case of zl = 0.7. Secondly, we considered the impact of hypothetical massive objects lying on the line-of-sight by scaling the theoretical time delay distance with an external convergence term κext such that \n\n\n\n\nD\n\nΔ\nt\n\n\n=\n\nD\n\nΔ\nt\n\n\n\ntheory\n\n\n\/\n\n(\n1\n−\n\nκ\n\n\next\n\n\n)\n\n\n\n$ D_{\\Delta t} = D_{\\Delta t}^{\\text{ theory}} \/ (1 - \\kappa_{\\text{ ext}}) $\n\n\n (see, e.g., Keeton 2003). We applied a different scaling for each set of model parameters used to construct the histograms (see Fig. 7). The κext values were randomly drawn from a zero mean normal distribution and characterized by a conservative standard deviation σκ = 0.03 (see, e.g., Wong et al. 2017). When combined, the typical errors are ∼7.7% for ΔtCB, ∼7.8% for ΔtCA, and ∼7.6% for ΔtCD, compared to the median values. Thirdly, we considered the impact of the Source Position Transformation (SPT), a degeneracy existing between different lens density profiles that reproduce equally well the lensing observables, except for the product Δt H0 (Schneider & Sluse 2013, 2014). A short summary is given in Appendix A. We SPT-transformed the SIEg model using the modified deflection law \n\n\n\n\n\nα\n\n̂\n\n=\n\n\nα\n\n\n\nSIEg\n\n\n+\n\nβ\n\n−\n\n\nβ\n\n̂\n\n\n(\n\nβ\n\n)\n\n\n\n$ {\\hat{\\boldsymbol{\\alpha}}} = \\boldsymbol{\\alpha}_{\\text{ SIEg}} + \\boldsymbol{\\beta} - {\\hat{\\boldsymbol{\\beta}}}(\\boldsymbol{\\beta}) $\n\n\n along with a radial stretching of the source plane defined by \n\n\n\n\n\nβ\n\n̂\n\n\n(\n\nβ\n\n)\n\n=\n\n[\n1\n+\nf\n(\n|\n\nβ\n\n|\n)\n]\n\n\nβ\n\n\n\n\n$ {\\hat{\\boldsymbol{\\beta}}}(\\boldsymbol{\\beta}) = [1 + f(|\\boldsymbol{\\beta}|)]\\ \\boldsymbol{\\beta} $\n\n\n. In particular, we considered the special case where the deformation function f(|β|) is the lowest-order expansion of more general functions, f(|β|) = f0 + f2|β|2\/(2θE), where the constants f0 = f(0) and \n\n\n\nf\n2\n\n=\nθ\nE\n2\n\n\nf\n\n′′\n\n(0)\n\n$ f_2 = \\theta_{{\\rm E}}^2 f^{\\prime\\prime}(0) $\n\n\n quantify the magnitude of the deformation. This choice explores a large variety of degeneracies characterized by an isotropic transformation of the source plane. In the end, this at least defines a lower limit on the impact of the SPT on the time delays. In the particular case of f2 = 0, the SPT reduces to the well-known mass-sheet degeneracy (MSD) characterized by \n\n\n\n\n\nβ\n\n̂\n\n\n(\n\nβ\n\n)\n\n=\nλ\n\nβ\n\n≡\n\n(\n1\n+\n\nf\n0\n\n)\n\n\nβ\n\n\n\n$ {\\hat{\\boldsymbol{\\beta}}}(\\boldsymbol{\\beta}) = \\lambda \\boldsymbol{\\beta} \\equiv (1 + f_0) \\boldsymbol{\\beta} $\n\n\n. In our analysis, we only explored degeneracies that cannot be explained by a MSD, hence f0 = 0.","Citation Text":["Keeton 2003"],"Citation Start End":[[745,756]]} {"Identifier":"2021ApJ...921..111Z__Shlomo_et_al._2006_Instance_1","Paragraph":"For completeness and ease of our discussions, here we summarize briefly the main features of the NS EOS-metamodel we use in solving the NS inverse-structure problem. More details can be found in our previous publications (Zhang et al. 2018; Xie & Li 2019, 2020; Zhang & Li 2019a, 2019b, 2019c, 2020). We assume the cores of NSs are made of totally charged neutral neutrons, protons, electrons, and muons (the npeμ model) at β-equilibrium. Unlike the widely used composition-degenerate spectral functions and\/or piecewise polytropes that directly parameterize the pressure as a function of energy or baryon density, to probe the high-density symmetry energy, we have to keep the isospin dependence of the EOS and retain explicitly the composition information at all densities. For this reason, we metamodel NS EOS by starting at the single-nucleon energy level with explicitly isospin dependence. Specifically, we parameterize the E0(ρ) and Esym(ρ) according to\n2\n\n\n\n\n\n\nE\n\n\n0\n\n\n(\nρ\n)\n=\n\n\nE\n\n\n0\n\n\n(\n\n\nρ\n\n\n0\n\n\n)\n+\n\n\n\n\n\nK\n\n\n0\n\n\n\n\n2\n\n\n\n\n\n\n\n\n\n\nρ\n−\n\n\nρ\n\n\n0\n\n\n\n\n3\n\n\nρ\n\n\n0\n\n\n\n\n\n\n\n\n\n2\n\n\n+\n\n\n\n\n\nJ\n\n\n0\n\n\n\n\n6\n\n\n\n\n\n\n\n\n\n\nρ\n−\n\n\nρ\n\n\n0\n\n\n\n\n3\n\n\nρ\n\n\n0\n\n\n\n\n\n\n\n\n\n3\n\n\n,\n\n\n\n\n3\n\n\n\n\n\n\n\n\n\nE\n\n\nsym\n\n\n(\nρ\n)\n\n\n=\n\n\n\n\nE\n\n\nsym\n\n\n\n\n\n\nρ\n\n\n0\n\n\n\n\n+\nL\n\n\n\n\n\nρ\n−\n\n\nρ\n\n\n0\n\n\n\n\n3\n\n\nρ\n\n\n0\n\n\n\n\n\n\n\n\n\n\n\n\n\n+\n\n\n\n\n\n\nK\n\n\nsym\n\n\n\n\n2\n\n\n\n\n\n\n\n\n\n\nρ\n−\n\n\nρ\n\n\n0\n\n\n\n\n3\n\n\nρ\n\n\n0\n\n\n\n\n\n\n\n\n\n2\n\n\n+\n\n\n\n\n\nJ\n\n\nsym\n\n\n\n\n6\n\n\n\n\n\n\n\n\n\n\nρ\n−\n\n\nρ\n\n\n0\n\n\n\n\n3\n\n\nρ\n\n\n0\n\n\n\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\nwhere E0(ρ0) = −15.9 ± 0.4 MeV is the binding energy and K0 ≈ 230 ± 20 MeV (Shlomo et al. 2006; Piekarewicz 2010; Garg & Colò 2018) is the incompressibility at the saturation density ρ0 of SNM, while Esym(ρ0) = 31.7 ± 3.2 MeV is the magnitude and L ≈ 58.7 ± 28.1 MeV is the slope of symmetry energy at ρ0 (Li & Han 2013; Oertel et al. 2017) based on earlier surveys of over 50 analyses of both terrestrial experiments and astrophysical observations, respectively. A very recent survey of 24 new analyses of NS observations since GW179817 indicates that L ≈ 57.7 ± 19 MeV and Ksym ≈ −107 ± 88 MeV at 68% confidence level (Li et al. 2021). In this study, we use L = 58.7 as its most probable value and vary it within ±20 MeV. We keep the E0(ρ0), K0, and Esym(ρ0) at their most probable values given above as they have been relatively well determined and their variations within their remaining uncertain ranges have been shown to have little effects on the masses, radii, and tidal deformabilities of NSs Fattoyev et al. (2013, 2014), Xie & Li (2019, 2020). As a reference, we notice that very recent calculations based on a set of commonly used Hamiltonian operators including two- and three-nucleon forces derived from chiral effective field theory predicted that L = 47 ± 3 MeV, Ksym = −146 ± 43 MeV, Jsym = 90 ± 334 MeV (Somasundaram et al. 2021). While in the same calculations, with a prior J0 = −300 ± 400 MeV, the posterior ranges between J0 =−573 ± 133 MeV and J0 = −172 ± 243 MeV depending on the scaling schemes used. The EOS parameter ranges we used are consistent with these calculations.","Citation Text":["Shlomo et al. 2006"],"Citation Start End":[[1480,1498]]} {"Identifier":"2021ApJ...908...18S__Principe_et_al._2005_Instance_1","Paragraph":"Next, we estimated the distance and reddening. As in Brown et al. (2014), we compared the Eri II main sequence to a synthetic Victoria-Regina theoretical isochrone from VandenBerg et al. (2014) and the horizontal branch of Eri II to the horizontal branch of M92, which was observed with the same ACS filters by Brown et al. (2005). The synthetic main-sequence isochrone was constructed assuming an age of 13 Gyr, the metallicity distribution displayed in Figure 3, and a binary fraction of 0.48 (Geha et al. 2013). For M92, we assumed a distance modulus of 14.62 mag (the mean of literature measurements by Del Principe et al. 2005, Sollima et al. 2006, and Paust et al. 2007) and reddening of E(B − V) = 0.023 mag (Schlegel et al. 1998). We included main-sequence stars more than 0.5 mag below the main-sequence turnoff (m814 > 27.67) in order to avoid portions that are age-sensitive, and we used horizontal branch stars that are bluer than m606 − m814 = −0.68 in order to avoid the RR Lyrae instability strip. Fitting the main sequence and the horizontal branch simultaneously, we found m − M = 22.65 mag (d = 339 kpc) and E(B − V) = 0.03 mag, as shown in Figure 4. This distance modulus is consistent, within the uncertainties, with the distance derived from the Eri II RR Lyrae stars by A. Garofalo et al. (2021, in preparation). The statistical uncertainties on the distance fit are very small (0.015 mag in distance modulus, 0.003 mag in reddening), and they are certainly dominated by systematics in the choice of comparison cluster\/isochrone and the magnitude and color range of stars to include. By analogy to Brown et al. (2014), we assume overall uncertainties of 0.07 mag in m − M and 0.01 mag in E(B − V). Similar to a few of the ultra-faint dwarfs studied by Brown et al. (2012, 2014), the distance modulus determined with this approach is in modest disagreement with some literature results (Crnojević et al. 2016 measured m − M = 22.8 ± 0.1 mag and Koposov et al. 2015 estimated m − M = 22.9 mag, although Bechtol et al. 2015 found a comparable value of m − M = 22.6 mag) and the derived reddening is larger than the E(B − V) = 0.009 mag value obtained by Schlafly & Finkbeiner (2011) (also see Mutlu-Pakdil et al. 2019). However, for consistency with previous star formation history analyses, we adopt the derived values for the remainder of this study.","Citation Text":["Del Principe et al. 2005"],"Citation Start End":[[607,631]]} {"Identifier":"2021ApJ...908...18SGeha_et_al._2013_Instance_1","Paragraph":"Next, we estimated the distance and reddening. As in Brown et al. (2014), we compared the Eri II main sequence to a synthetic Victoria-Regina theoretical isochrone from VandenBerg et al. (2014) and the horizontal branch of Eri II to the horizontal branch of M92, which was observed with the same ACS filters by Brown et al. (2005). The synthetic main-sequence isochrone was constructed assuming an age of 13 Gyr, the metallicity distribution displayed in Figure 3, and a binary fraction of 0.48 (Geha et al. 2013). For M92, we assumed a distance modulus of 14.62 mag (the mean of literature measurements by Del Principe et al. 2005, Sollima et al. 2006, and Paust et al. 2007) and reddening of E(B − V) = 0.023 mag (Schlegel et al. 1998). We included main-sequence stars more than 0.5 mag below the main-sequence turnoff (m814 > 27.67) in order to avoid portions that are age-sensitive, and we used horizontal branch stars that are bluer than m606 − m814 = −0.68 in order to avoid the RR Lyrae instability strip. Fitting the main sequence and the horizontal branch simultaneously, we found m − M = 22.65 mag (d = 339 kpc) and E(B − V) = 0.03 mag, as shown in Figure 4. This distance modulus is consistent, within the uncertainties, with the distance derived from the Eri II RR Lyrae stars by A. Garofalo et al. (2021, in preparation). The statistical uncertainties on the distance fit are very small (0.015 mag in distance modulus, 0.003 mag in reddening), and they are certainly dominated by systematics in the choice of comparison cluster\/isochrone and the magnitude and color range of stars to include. By analogy to Brown et al. (2014), we assume overall uncertainties of 0.07 mag in m − M and 0.01 mag in E(B − V). Similar to a few of the ultra-faint dwarfs studied by Brown et al. (2012, 2014), the distance modulus determined with this approach is in modest disagreement with some literature results (Crnojević et al. 2016 measured m − M = 22.8 ± 0.1 mag and Koposov et al. 2015 estimated m − M = 22.9 mag, although Bechtol et al. 2015 found a comparable value of m − M = 22.6 mag) and the derived reddening is larger than the E(B − V) = 0.009 mag value obtained by Schlafly & Finkbeiner (2011) (also see Mutlu-Pakdil et al. 2019). However, for consistency with previous star formation history analyses, we adopt the derived values for the remainder of this study.","Citation Text":["Geha et al. 2013"],"Citation Start End":[[496,512]]} {"Identifier":"2021ApJ...908...18SA._Garofalo_et_al._(2021,_in_preparation)_Instance_1","Paragraph":"Next, we estimated the distance and reddening. As in Brown et al. (2014), we compared the Eri II main sequence to a synthetic Victoria-Regina theoretical isochrone from VandenBerg et al. (2014) and the horizontal branch of Eri II to the horizontal branch of M92, which was observed with the same ACS filters by Brown et al. (2005). The synthetic main-sequence isochrone was constructed assuming an age of 13 Gyr, the metallicity distribution displayed in Figure 3, and a binary fraction of 0.48 (Geha et al. 2013). For M92, we assumed a distance modulus of 14.62 mag (the mean of literature measurements by Del Principe et al. 2005, Sollima et al. 2006, and Paust et al. 2007) and reddening of E(B − V) = 0.023 mag (Schlegel et al. 1998). We included main-sequence stars more than 0.5 mag below the main-sequence turnoff (m814 > 27.67) in order to avoid portions that are age-sensitive, and we used horizontal branch stars that are bluer than m606 − m814 = −0.68 in order to avoid the RR Lyrae instability strip. Fitting the main sequence and the horizontal branch simultaneously, we found m − M = 22.65 mag (d = 339 kpc) and E(B − V) = 0.03 mag, as shown in Figure 4. This distance modulus is consistent, within the uncertainties, with the distance derived from the Eri II RR Lyrae stars by A. Garofalo et al. (2021, in preparation). The statistical uncertainties on the distance fit are very small (0.015 mag in distance modulus, 0.003 mag in reddening), and they are certainly dominated by systematics in the choice of comparison cluster\/isochrone and the magnitude and color range of stars to include. By analogy to Brown et al. (2014), we assume overall uncertainties of 0.07 mag in m − M and 0.01 mag in E(B − V). Similar to a few of the ultra-faint dwarfs studied by Brown et al. (2012, 2014), the distance modulus determined with this approach is in modest disagreement with some literature results (Crnojević et al. 2016 measured m − M = 22.8 ± 0.1 mag and Koposov et al. 2015 estimated m − M = 22.9 mag, although Bechtol et al. 2015 found a comparable value of m − M = 22.6 mag) and the derived reddening is larger than the E(B − V) = 0.009 mag value obtained by Schlafly & Finkbeiner (2011) (also see Mutlu-Pakdil et al. 2019). However, for consistency with previous star formation history analyses, we adopt the derived values for the remainder of this study.","Citation Text":["A. Garofalo et al. (2021, in preparation)"],"Citation Start End":[[1292,1333]]} {"Identifier":"2021ApJ...908...18SCrnojević_et_al._2016_Instance_1","Paragraph":"Next, we estimated the distance and reddening. As in Brown et al. (2014), we compared the Eri II main sequence to a synthetic Victoria-Regina theoretical isochrone from VandenBerg et al. (2014) and the horizontal branch of Eri II to the horizontal branch of M92, which was observed with the same ACS filters by Brown et al. (2005). The synthetic main-sequence isochrone was constructed assuming an age of 13 Gyr, the metallicity distribution displayed in Figure 3, and a binary fraction of 0.48 (Geha et al. 2013). For M92, we assumed a distance modulus of 14.62 mag (the mean of literature measurements by Del Principe et al. 2005, Sollima et al. 2006, and Paust et al. 2007) and reddening of E(B − V) = 0.023 mag (Schlegel et al. 1998). We included main-sequence stars more than 0.5 mag below the main-sequence turnoff (m814 > 27.67) in order to avoid portions that are age-sensitive, and we used horizontal branch stars that are bluer than m606 − m814 = −0.68 in order to avoid the RR Lyrae instability strip. Fitting the main sequence and the horizontal branch simultaneously, we found m − M = 22.65 mag (d = 339 kpc) and E(B − V) = 0.03 mag, as shown in Figure 4. This distance modulus is consistent, within the uncertainties, with the distance derived from the Eri II RR Lyrae stars by A. Garofalo et al. (2021, in preparation). The statistical uncertainties on the distance fit are very small (0.015 mag in distance modulus, 0.003 mag in reddening), and they are certainly dominated by systematics in the choice of comparison cluster\/isochrone and the magnitude and color range of stars to include. By analogy to Brown et al. (2014), we assume overall uncertainties of 0.07 mag in m − M and 0.01 mag in E(B − V). Similar to a few of the ultra-faint dwarfs studied by Brown et al. (2012, 2014), the distance modulus determined with this approach is in modest disagreement with some literature results (Crnojević et al. 2016 measured m − M = 22.8 ± 0.1 mag and Koposov et al. 2015 estimated m − M = 22.9 mag, although Bechtol et al. 2015 found a comparable value of m − M = 22.6 mag) and the derived reddening is larger than the E(B − V) = 0.009 mag value obtained by Schlafly & Finkbeiner (2011) (also see Mutlu-Pakdil et al. 2019). However, for consistency with previous star formation history analyses, we adopt the derived values for the remainder of this study.","Citation Text":["Crnojević et al. 2016"],"Citation Start End":[[1908,1929]]} {"Identifier":"2017MNRAS.469S..29A__Eriksson_et_al._2017_Instance_1","Paragraph":"To model the inner coma plasma, we use the simplified model by Eriksson et al. (2017). Neutral gas flows outward from the comet with a velocity of about 0.7 km s−1 (Gulkis et al. 2015), with the density decreasing as r−2(1)\r\n\\begin{equation}\r\nn_{{\\rm n}} (r) \\approx n_{0} \\left( \\frac{R}{r} \\right)^{2},\r\n\\end{equation}\r\nwhere n0 is the neutral gas density at the surface of a comet with radius R, and nn is the density at the cometocentric distance r. Assuming that steady ionization by solar EUV radiation dominates, this gives a peak in plasma density at some cometocentric distance, and a decrease of this density as r−1 at large distances (since the density of neutrals is typically much higher than the plasma density):\n(2)\r\n\\begin{equation}\r\nn_{{\\rm e}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere ne is the electron density at some distance r, ν is an ionization frequency depending on the distance to the sun and u is the outflow velocity of the plasma (Haser 1957; Mandt et al. 2016; Eriksson et al. 2017; Vigren & Eriksson 2017; Vigren 2017). Assuming that the plasma is dominated by water ions from the comet, ion–electron pairs are created with particle energies of less than 0.1 and about 12 eV, respectively (due to conservation of momentum). When the density is high enough close to the nucleus, neutral-electron collisions will cool the electrons to temperatures of 0.1 eV or less. Beyond some distance rce the electrons are not efficiently cooled, and a mixture of cool (0.1 eV) and warm (5–10 eV) electrons are observed (Edberg et al. 2015; Mandt et al. 2016; Eriksson et al. 2017). Collisions between neutrals and ions are important out to larger distances. We investigate the region where electron-neutral collisions can be neglected, and warm electrons are present and magnetized, while the ions are unmagnetized due to collisions and their large gyroradius. This is a region favourable for lower hybrid waves and is where Rosetta spend much of its time during the 2 yr investigation of 67P (Mandt et al. 2016). We use three populations to model the plasma, cold and warm electrons, and H2O + ions\n(3)\r\n\\begin{equation}\r\nn_{{\\rm ew}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{r_{{\\rm ce}}}{r}\\right) \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(4)\r\n\\begin{equation}\r\nn_{{\\rm ec}} (r) \\approx n_{{\\rm e}} (r_{{\\rm ce}}) \\frac{r^2_{{\\rm ce}}}{r^2} = n_0 \\frac{\\nu R}{u} \\frac{Rr_{{\\rm ce}}}{r^2} \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(5)\r\n\\begin{equation}\r\nn_{{\\rm i}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere new, nec and ni are the densities of warm and cold electrons, and ions, respectively (Eriksson et al. 2017). For distances smaller than rce, the electron motion is disrupted by collisions and lower hybrid waves are likely to be heavily damped.","Citation Text":["Eriksson et al. (2017)"],"Citation Start End":[[63,85]]} {"Identifier":"2017MNRAS.469S..29A__Eriksson_et_al._2017_Instance_2","Paragraph":"To model the inner coma plasma, we use the simplified model by Eriksson et al. (2017). Neutral gas flows outward from the comet with a velocity of about 0.7 km s−1 (Gulkis et al. 2015), with the density decreasing as r−2(1)\r\n\\begin{equation}\r\nn_{{\\rm n}} (r) \\approx n_{0} \\left( \\frac{R}{r} \\right)^{2},\r\n\\end{equation}\r\nwhere n0 is the neutral gas density at the surface of a comet with radius R, and nn is the density at the cometocentric distance r. Assuming that steady ionization by solar EUV radiation dominates, this gives a peak in plasma density at some cometocentric distance, and a decrease of this density as r−1 at large distances (since the density of neutrals is typically much higher than the plasma density):\n(2)\r\n\\begin{equation}\r\nn_{{\\rm e}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere ne is the electron density at some distance r, ν is an ionization frequency depending on the distance to the sun and u is the outflow velocity of the plasma (Haser 1957; Mandt et al. 2016; Eriksson et al. 2017; Vigren & Eriksson 2017; Vigren 2017). Assuming that the plasma is dominated by water ions from the comet, ion–electron pairs are created with particle energies of less than 0.1 and about 12 eV, respectively (due to conservation of momentum). When the density is high enough close to the nucleus, neutral-electron collisions will cool the electrons to temperatures of 0.1 eV or less. Beyond some distance rce the electrons are not efficiently cooled, and a mixture of cool (0.1 eV) and warm (5–10 eV) electrons are observed (Edberg et al. 2015; Mandt et al. 2016; Eriksson et al. 2017). Collisions between neutrals and ions are important out to larger distances. We investigate the region where electron-neutral collisions can be neglected, and warm electrons are present and magnetized, while the ions are unmagnetized due to collisions and their large gyroradius. This is a region favourable for lower hybrid waves and is where Rosetta spend much of its time during the 2 yr investigation of 67P (Mandt et al. 2016). We use three populations to model the plasma, cold and warm electrons, and H2O + ions\n(3)\r\n\\begin{equation}\r\nn_{{\\rm ew}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{r_{{\\rm ce}}}{r}\\right) \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(4)\r\n\\begin{equation}\r\nn_{{\\rm ec}} (r) \\approx n_{{\\rm e}} (r_{{\\rm ce}}) \\frac{r^2_{{\\rm ce}}}{r^2} = n_0 \\frac{\\nu R}{u} \\frac{Rr_{{\\rm ce}}}{r^2} \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(5)\r\n\\begin{equation}\r\nn_{{\\rm i}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere new, nec and ni are the densities of warm and cold electrons, and ions, respectively (Eriksson et al. 2017). For distances smaller than rce, the electron motion is disrupted by collisions and lower hybrid waves are likely to be heavily damped.","Citation Text":["Eriksson et al. 2017"],"Citation Start End":[[1049,1069]]} {"Identifier":"2017MNRAS.469S..29A__Eriksson_et_al._2017_Instance_3","Paragraph":"To model the inner coma plasma, we use the simplified model by Eriksson et al. (2017). Neutral gas flows outward from the comet with a velocity of about 0.7 km s−1 (Gulkis et al. 2015), with the density decreasing as r−2(1)\r\n\\begin{equation}\r\nn_{{\\rm n}} (r) \\approx n_{0} \\left( \\frac{R}{r} \\right)^{2},\r\n\\end{equation}\r\nwhere n0 is the neutral gas density at the surface of a comet with radius R, and nn is the density at the cometocentric distance r. Assuming that steady ionization by solar EUV radiation dominates, this gives a peak in plasma density at some cometocentric distance, and a decrease of this density as r−1 at large distances (since the density of neutrals is typically much higher than the plasma density):\n(2)\r\n\\begin{equation}\r\nn_{{\\rm e}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere ne is the electron density at some distance r, ν is an ionization frequency depending on the distance to the sun and u is the outflow velocity of the plasma (Haser 1957; Mandt et al. 2016; Eriksson et al. 2017; Vigren & Eriksson 2017; Vigren 2017). Assuming that the plasma is dominated by water ions from the comet, ion–electron pairs are created with particle energies of less than 0.1 and about 12 eV, respectively (due to conservation of momentum). When the density is high enough close to the nucleus, neutral-electron collisions will cool the electrons to temperatures of 0.1 eV or less. Beyond some distance rce the electrons are not efficiently cooled, and a mixture of cool (0.1 eV) and warm (5–10 eV) electrons are observed (Edberg et al. 2015; Mandt et al. 2016; Eriksson et al. 2017). Collisions between neutrals and ions are important out to larger distances. We investigate the region where electron-neutral collisions can be neglected, and warm electrons are present and magnetized, while the ions are unmagnetized due to collisions and their large gyroradius. This is a region favourable for lower hybrid waves and is where Rosetta spend much of its time during the 2 yr investigation of 67P (Mandt et al. 2016). We use three populations to model the plasma, cold and warm electrons, and H2O + ions\n(3)\r\n\\begin{equation}\r\nn_{{\\rm ew}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{r_{{\\rm ce}}}{r}\\right) \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(4)\r\n\\begin{equation}\r\nn_{{\\rm ec}} (r) \\approx n_{{\\rm e}} (r_{{\\rm ce}}) \\frac{r^2_{{\\rm ce}}}{r^2} = n_0 \\frac{\\nu R}{u} \\frac{Rr_{{\\rm ce}}}{r^2} \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(5)\r\n\\begin{equation}\r\nn_{{\\rm i}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere new, nec and ni are the densities of warm and cold electrons, and ions, respectively (Eriksson et al. 2017). For distances smaller than rce, the electron motion is disrupted by collisions and lower hybrid waves are likely to be heavily damped.","Citation Text":["Eriksson et al. 2017"],"Citation Start End":[[1634,1654]]} {"Identifier":"2017MNRAS.469S..29A__Eriksson_et_al._2017_Instance_4","Paragraph":"To model the inner coma plasma, we use the simplified model by Eriksson et al. (2017). Neutral gas flows outward from the comet with a velocity of about 0.7 km s−1 (Gulkis et al. 2015), with the density decreasing as r−2(1)\r\n\\begin{equation}\r\nn_{{\\rm n}} (r) \\approx n_{0} \\left( \\frac{R}{r} \\right)^{2},\r\n\\end{equation}\r\nwhere n0 is the neutral gas density at the surface of a comet with radius R, and nn is the density at the cometocentric distance r. Assuming that steady ionization by solar EUV radiation dominates, this gives a peak in plasma density at some cometocentric distance, and a decrease of this density as r−1 at large distances (since the density of neutrals is typically much higher than the plasma density):\n(2)\r\n\\begin{equation}\r\nn_{{\\rm e}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere ne is the electron density at some distance r, ν is an ionization frequency depending on the distance to the sun and u is the outflow velocity of the plasma (Haser 1957; Mandt et al. 2016; Eriksson et al. 2017; Vigren & Eriksson 2017; Vigren 2017). Assuming that the plasma is dominated by water ions from the comet, ion–electron pairs are created with particle energies of less than 0.1 and about 12 eV, respectively (due to conservation of momentum). When the density is high enough close to the nucleus, neutral-electron collisions will cool the electrons to temperatures of 0.1 eV or less. Beyond some distance rce the electrons are not efficiently cooled, and a mixture of cool (0.1 eV) and warm (5–10 eV) electrons are observed (Edberg et al. 2015; Mandt et al. 2016; Eriksson et al. 2017). Collisions between neutrals and ions are important out to larger distances. We investigate the region where electron-neutral collisions can be neglected, and warm electrons are present and magnetized, while the ions are unmagnetized due to collisions and their large gyroradius. This is a region favourable for lower hybrid waves and is where Rosetta spend much of its time during the 2 yr investigation of 67P (Mandt et al. 2016). We use three populations to model the plasma, cold and warm electrons, and H2O + ions\n(3)\r\n\\begin{equation}\r\nn_{{\\rm ew}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{r_{{\\rm ce}}}{r}\\right) \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(4)\r\n\\begin{equation}\r\nn_{{\\rm ec}} (r) \\approx n_{{\\rm e}} (r_{{\\rm ce}}) \\frac{r^2_{{\\rm ce}}}{r^2} = n_0 \\frac{\\nu R}{u} \\frac{Rr_{{\\rm ce}}}{r^2} \\quad \\quad r \\ge r_{{\\rm ce}},\r\n\\end{equation}\r\n(5)\r\n\\begin{equation}\r\nn_{{\\rm i}} (r) \\approx n_{0} \\frac{\\nu R}{u} \\frac{R}{r} \\left(1-\\frac{R}{r} \\right),\r\n\\end{equation}\r\nwhere new, nec and ni are the densities of warm and cold electrons, and ions, respectively (Eriksson et al. 2017). For distances smaller than rce, the electron motion is disrupted by collisions and lower hybrid waves are likely to be heavily damped.","Citation Text":["Eriksson et al. 2017"],"Citation Start End":[[2762,2782]]} {"Identifier":"2020MNRAS.497..917L__Elias,_Frogel_&_Humphreys_1985_Instance_1","Paragraph":"Multiwavelength searches for the donor stars have been pursued for more than a decade. Some have observed ULXs in the optical range (e.g. Gutiérrez & López-Corredoira 2006; Ptak et al. 2006; Roberts et al. 2011; Gladstone et al. 2013; Fabrika et al. 2015). As several of the ULXs are located in or near young star clusters (e.g. Fabbiano, Zezas & Murray 2001; Roberts et al. 2002; Poutanen et al. 2013), some donor stars of ULXs might as well be RSGs (Copperwheat et al. 2005, 2007; Patruno & Zampieri 2008), which are bright in the near-infrared (NIR) band. In light of this, we started an observing campaign of ULXs in the NIR (Heida et al. 2014; López et al. 2017), tailored to detect RSG donor stars (−8 H, Ks −11; Elias, Frogel & Humphreys 1985; Drilling & Landolt 2000). We targeted sources at distances of up to 10 Mpc, within uncertainties. Of the 97 ULXs observed by Heida et al. (2014) and López et al. (2017), we detected a NIR candidate counterpart for 33 ULXs. Of these 33 NIR sources, 19 had the absolute magnitude consistent with an RSG. So far, we performed spectroscopic follow-up observations for 7 out of these 19 candidate RSGs and confirmed the RSG nature for 3 counterparts: ULX RX J004722.4−252051 (in NGC 253; Heida et al. 2015a), ULX J022721+333500 (in NGC 925), and ULX J120922+295559 (in NGC 4136; Heida et al. 2016). Additionally, we discovered that four counterparts, initially classified as RSG based on photometry, are actually nebulae partially powered by the X-ray emission of the ULX: ULX J022727+333443 (in NGC 925), ULX J120922+295551 (in NGC 4136), ULX Ho II X-1 (in Holmberg II; Heida et al. 2016), and [SST2011] J110545.62+000016.2 (in NGC 3521; López et al. 2019). This means that, at the time of writing this manuscript, the photometric and spectroscopic observations provided 3 confirmed RSGs, 12 candidate RSGs, 4 confirmed nebulae, and 14 candidate stellar clusters\/active galactic nuclei (AGNs). Recently, Lau et al. (2019) observed 96 ULXs within 10 Mpc in the mid-IR with the Spitzer Space Telescope. They detected and identified 12 ULXs with candidate counterparts whose absolute mid-IR magnitude is consistent with being RSGs.","Citation Text":["Elias, Frogel & Humphreys 1985"],"Citation Start End":[[721,751]]} {"Identifier":"2017AandA...604A..23N__Ciddor_1996_Instance_1","Paragraph":"We first focus on the properties of the PDLA obtained through the VPFit code. Together with the fitted absorption profile, both the column density and the redshift of the PDLA are derived: (8)\\begin{equation} \\log(N) = 20.9290 \\pm 0.0024;~~~ z_{\\rm abs} = 3.082097 \\pm 0.000053. \\label{eq:col_dens_zabs} \\end{equation}log(N)=20.9290±0.0024;zabs=3.082097±0.000053.The redshift value obtained here differs by no more than 0.000163 from the value obtained based on metallic lines and is thus entirely consistent with it (see Sect. 3.2 above). We took the refractive index n of air into account that causes a shift in the observed wavelengths: λair = λvac\/n. We used the Ciddor equation (Ciddor 1996), taking the atmospheric conditions at the time of the measurement into account (air temperature 12°C, pressure 744.9 hPa, and relative humidity 3%, as reported in the header of the original FITS file). The errors are the formal errors provided by VPFit and are certainly underestimated, as they do not include uncertainties linked to the continuum determination. In their pioneer study, Leibundgut & Robertson (1999) obtained a column density and redshift \\begin{eqnarray*} \\log(N) = 20.85 \\pm 0.03;~~~ z_{\\rm abs} = 3.0825. \\end{eqnarray*}log(N)=20.85±0.03;zabs=3.0825.Our estimate of the column density is higher than theirs by 2.6σ (referring to their error estimate), and we find a slightly lower redshift (the difference amounts to 7.6σ according to our own error estimate). The latter discrepancy might be due to our lower spectral resolution (R ~ 1840 instead of 3300), which might cause the metallic absorption lines in the blue wing of the Lyα absorption trough to be less easily recognized and be partly included in the Voigt profile fit. This would result in a slightly overestimated column densitiy and in a slight blue shift. However, our VPFit estimate of the redshift, based on the Lyα line alone, agrees within only 0.5σ with the PDLA redshift estimate based on metallic lines. ","Citation Text":["Ciddor 1996"],"Citation Start End":[[684,695]]} {"Identifier":"2017AandA...604A..2Leibundgut_&_Robertson_(1999)_Instance_1","Paragraph":"We first focus on the properties of the PDLA obtained through the VPFit code. Together with the fitted absorption profile, both the column density and the redshift of the PDLA are derived: (8)\\begin{equation} \\log(N) = 20.9290 \\pm 0.0024;~~~ z_{\\rm abs} = 3.082097 \\pm 0.000053. \\label{eq:col_dens_zabs} \\end{equation}log(N)=20.9290±0.0024;zabs=3.082097±0.000053.The redshift value obtained here differs by no more than 0.000163 from the value obtained based on metallic lines and is thus entirely consistent with it (see Sect. 3.2 above). We took the refractive index n of air into account that causes a shift in the observed wavelengths: λair = λvac\/n. We used the Ciddor equation (Ciddor 1996), taking the atmospheric conditions at the time of the measurement into account (air temperature 12°C, pressure 744.9 hPa, and relative humidity 3%, as reported in the header of the original FITS file). The errors are the formal errors provided by VPFit and are certainly underestimated, as they do not include uncertainties linked to the continuum determination. In their pioneer study, Leibundgut & Robertson (1999) obtained a column density and redshift \\begin{eqnarray*} \\log(N) = 20.85 \\pm 0.03;~~~ z_{\\rm abs} = 3.0825. \\end{eqnarray*}log(N)=20.85±0.03;zabs=3.0825.Our estimate of the column density is higher than theirs by 2.6σ (referring to their error estimate), and we find a slightly lower redshift (the difference amounts to 7.6σ according to our own error estimate). The latter discrepancy might be due to our lower spectral resolution (R ~ 1840 instead of 3300), which might cause the metallic absorption lines in the blue wing of the Lyα absorption trough to be less easily recognized and be partly included in the Voigt profile fit. This would result in a slightly overestimated column densitiy and in a slight blue shift. However, our VPFit estimate of the redshift, based on the Lyα line alone, agrees within only 0.5σ with the PDLA redshift estimate based on metallic lines. ","Citation Text":["Leibundgut & Robertson (1999)"],"Citation Start End":[[1084,1113]]} {"Identifier":"2017ApJ...834..135T__Lang_et_al._2014_Instance_1","Paragraph":"We quantitatively assess the possibility of bulge formation in our sample of the 12 massive galaxies with reliable size measurements of dust continuum emission. Quiescent galaxies generally have a dense core with high stellar mass surface densities within 1 kpc of galaxy centers of \n\n\n\n\n\n, while star-forming galaxies mostly do not (van Dokkum et al. 2014; Barro et al. 2015). For our sample, we create stellar mass maps by spatially resolved SED modeling with multiband HST data (Wuyts et al. 2012; Lang et al. 2014) to calculate stellar mass surface densities within 1 kpc from the 870 μm center. None of the members of our sample satisfy the criterion of a dense core at the current moment (Table 2). The spatial distribution of star formation within galaxies allows us to understand when the dense core is formed by subsequent star formation. Exploiting the geometric information of the best-fit exponential models at 870 μm, we derive the SFR surface densities within the central 1 kpc (ΣSFR1 kpc) from the Spitzer\/Herschel-based total SFRs over galaxies. For nine galaxies with compact dust emission of \n\n\n\n\n\n, they are intensely forming stars in the central region with ΣSFR1 kpc = 40 (19–65) M⊙ yr−1 kpc−2 (Table 2). Then, bulge formation timescales to reach \n\n\n\n\n\n kpc−2) = 10 are estimated by\n3\n\n\n\n\n\ntaking into account mass loss due to stellar winds (w = 0.6 in Chabrier IMF; see also van Dokkum et al. 2014). The estimated bulge formation timescales are \n\n\n\n\n\n (8.16–8.79) for the nine galaxies with R1\/2,870 μm 1. 5 kpc. They can complete the dense core formation by z = 2 when the current level of star formation is maintained for several hundred megayears. Galaxies forming stars in disks as extended as the rest-optical light would have to keep the current star formation for a longer time (∼2 Gyr). This is not consistent with stellar populations obtained in high-redshift quiescent galaxies, where timescales for star formation are τ 1 Gyr (e.g., Belli et al. 2015; Onodera et al. 2015).","Citation Text":["Lang et al. 2014"],"Citation Start End":[[501,517]]} {"Identifier":"2015ApJ...798...60K__Dickman_1978_Instance_1","Paragraph":"For Region 1, we adopt a thick, uniform disk approximation and assume that we view this disk edge-on. In this case, the density can be obtained by dividing the central\/maximum column density toward the axis by the diameter\/width of the disk, i.e., the depth. The average of color excess E(H − Ks) is ∼1.5 ± 0.7 mag for 20 sources detected toward the central part of Region 1 (within 60″ of the symmetric axis), and cm−2 is roughly obtained, using the reddening law, E(H − Ks) = 0.065 × AV (Chini & Wargau 1998), and the standard gas-to-extinction ratio, cm−2 mag−1 (Dickman 1978). This estimated column density seems to be consistent with that estimated from the CO data, ∼1.3–4.1 × 1022 cm−2. Adopting a width of ∼30 (∼1.4 pc) as the depth of Region 1, we can derive a number density of cm−3. Since Region 2 is located around the symmetric axis of the cloud, the column density in Region 2 is expected to be close to the central\/maximum column density if the local density is uniform. The average of color excess E(H − Ks) is ∼1.1 ± 0.4 mag for 41 sources toward Region 2, and cm−2 is roughly obtained. This column density also seems to be consistent with that estimated from the CO data, ≲ 2.1 × 1022 cm−2. Adopting the width of ∼80 (∼3.5 pc) as the depth of Region 2, cm−3 can be obtained in Region 2. The estimated number density in Region 1 is ∼3–4 times higher than that in Region 2, supporting the idea that Region 1 was strongly compressed by UV and then became higher in density. This result does not seem to match the simulation results for the nonmagnetized clouds that the number density in the tip is expected to be higher by more than one order of magnitude than that of the area away from the tip (e.g., Figures 3, 7, and 10 of Miao et al. 2009). However, the simulation taking into account the magnetic pressure predicts a smaller difference of a factor of 10 (e.g., Figure 8 of Miao et al. 2006), which is more consistent with our observations. Motoyama et al. (2013) also suggests flatter column density profiles in the magnetized cases than in the nonmagnetized ones.","Citation Text":["Dickman 1978"],"Citation Start End":[[584,596]]} {"Identifier":"2016ApJ...819...25K__Verhamme_et_al._2012_Instance_1","Paragraph":"In the interpretation of clumpy star formation in a disk-like galaxy, as usually observed in high-z galaxies (e.g., Elmegreen et al. 2009; Förster Schreiber et al. 2011; Murata et al. 2014; Tadaki et al. 2014), the ellipticity of a source may be an intrinsic property related to the viewing angle of the disk. That is, large ellipticity implies that its viewing angle is close to edge-on and that the stellar disk lies in the elongated direction. If we consider that Lyα is emitted in directions perpendicular to the disk, as predicted by the recent theoretical studies for Lyα line transfer (e.g., Verhamme et al. 2012; Yajima et al. 2012b), the pitch angle of Lyα emission will be at right angles to that of UV continuum. Moreover, in such a case, it is also expected that the size in Lyα emission aHL(NB711) shows a positive correlation with ellipticity measured in rest-frame UV continuum because the Lyα-emitting region in bipolar directions perpendicular to the disk can be viewed from longer distances if the viewing angle of the disk is closer to edge-on, that is, larger ellipticity. However, as presented in the top panel of Figure 17, we do not find such positive correlation between aHL(NB711) and ellipticity for the 54 ACS-detected LAEs. Furthermore, as shown in the bottom panel of Figure 17,14 the observed distribution of the LAEs in the EW0– plane seems not to be quantitatively consistent with the interpretation of clumpy star formation in a disk-like galaxy, where EW0 is expected to decrease significantly toward the edge-on direction (i.e., larger ellipticity) via radiative transfer effects for Lyα resonance photons (e.g., Verhamme et al. 2012; Yajima et al. 2012b); this result is consistent with Shibuya et al. (2014). Therefore, the interpretation of clumpy star formation in a disk-like galaxy seems not to be preferred for our LAE sample. This conclusion can be reinforced with the absence of an ACS source with a large size and round shape; if there are multiple clumpy star-forming regions in a disk-like galaxy, some such galaxies will be viewed face-on, resulting in alarge size and round shape. We emphasize again that this result is not affected by a selection bias against them if they are bright enough (i.e., I814 ≲ 26 mag), as shown in Figures 7 and 18.\n14\nNote that, considering the strong positive correlation between aHL and shown in Figure 8, this plot is qualitatively identical to the distribution in the EW0–aHL plane shown in the top panel of Figure 16.\n\n","Citation Text":["Verhamme et al. 2012","Verhamme et al. 2012"],"Citation Start End":[[599,619],[1648,1668]]} {"Identifier":"2016ApJ...819...25KElmegreen_et_al._2009_Instance_1","Paragraph":"In the interpretation of clumpy star formation in a disk-like galaxy, as usually observed in high-z galaxies (e.g., Elmegreen et al. 2009; Förster Schreiber et al. 2011; Murata et al. 2014; Tadaki et al. 2014), the ellipticity of a source may be an intrinsic property related to the viewing angle of the disk. That is, large ellipticity implies that its viewing angle is close to edge-on and that the stellar disk lies in the elongated direction. If we consider that Lyα is emitted in directions perpendicular to the disk, as predicted by the recent theoretical studies for Lyα line transfer (e.g., Verhamme et al. 2012; Yajima et al. 2012b), the pitch angle of Lyα emission will be at right angles to that of UV continuum. Moreover, in such a case, it is also expected that the size in Lyα emission aHL(NB711) shows a positive correlation with ellipticity measured in rest-frame UV continuum because the Lyα-emitting region in bipolar directions perpendicular to the disk can be viewed from longer distances if the viewing angle of the disk is closer to edge-on, that is, larger ellipticity. However, as presented in the top panel of Figure 17, we do not find such positive correlation between aHL(NB711) and ellipticity for the 54 ACS-detected LAEs. Furthermore, as shown in the bottom panel of Figure 17,14 the observed distribution of the LAEs in the EW0– plane seems not to be quantitatively consistent with the interpretation of clumpy star formation in a disk-like galaxy, where EW0 is expected to decrease significantly toward the edge-on direction (i.e., larger ellipticity) via radiative transfer effects for Lyα resonance photons (e.g., Verhamme et al. 2012; Yajima et al. 2012b); this result is consistent with Shibuya et al. (2014). Therefore, the interpretation of clumpy star formation in a disk-like galaxy seems not to be preferred for our LAE sample. This conclusion can be reinforced with the absence of an ACS source with a large size and round shape; if there are multiple clumpy star-forming regions in a disk-like galaxy, some such galaxies will be viewed face-on, resulting in alarge size and round shape. We emphasize again that this result is not affected by a selection bias against them if they are bright enough (i.e., I814 ≲ 26 mag), as shown in Figures 7 and 18.\n14\nNote that, considering the strong positive correlation between aHL and shown in Figure 8, this plot is qualitatively identical to the distribution in the EW0–aHL plane shown in the top panel of Figure 16.\n\n","Citation Text":["Elmegreen et al. 2009"],"Citation Start End":[[116,137]]} {"Identifier":"2015ApJ...810...69M__Hockney_&_Eastwood_1988_Instance_1","Paragraph":"On the basis of the absolute PM estimate derived in the previous section, we performed a numerical integration of the orbit of Terzan 5 in the Galactic potential. We used the three-component (bulge, disk, and halo) axisymmetric model from Allen & Santillan (1991), which has been extensively used and discussed in the literature to study orbits and dynamical environmental effects on Galactic stellar systems (e.g., Allen et al. 2006; Montuori et al. 2007; Ortolani et al. 2011; Moreno et al. 2014; Zonoozi et al. 2014), thanks to its relative simplicity and fully analytic nature. We adjusted the various model parameters to make the rotation velocity curve match the value of 243 km s−1 measured at the Solar Galactocentric distance of 8.4 kpc (see above). The cluster PMs were reported in the Cartesian Galactocentric reference frame, resulting in a velocity vector (vx, vy, vz) = (−60.4 ± 1.3, 85.7 ± 11.1, 35.0 ± 6.0) km s−1 at the position (x, y, z) = (−2.51 ± 0.30, 0.39 ± 0.02, 0.17 ± 0.01) kpc. We adopted the convention in which the X axis points opposite to the Sun (i.e., the Sun position is (−8.4,0,0)). The orbit was then time-integrated backwards for 12 Gyr, starting from the given initial (current) conditions and using a second-order leapfrog integrator (e.g., Hockney & Eastwood 1988) with a rather small and constant time step (∼100 kyr, corresponding to \n\n\n\n\n\n of the dynamical time at the Sun distance, computed as \n\n\n\n\n\n, where \n\n\n\n\n\n is a characteristic Galactic mass parameter). During the >105 time steps used to describe the entire orbit evolution, the errors on the conservation of both the energy and the Z component of angular momentum were kept under control and never exceeded one part over 105 and 1013, respectively. To take into account the uncertainties on the kinematic data, we generated a set of 1,000 orbits starting from the phase-space initial conditions normally distributed within a 3σ range around the cluster velocity vector components and the current position, with σ being equal to the quoted uncertainties on these parameters. For all of these orbits we repeated the backward time integration. The probability densities of the resulting orbits projected on the equatorial and meridional Galactic planes are shown in Figures 13 and 14, respectively. Darker colors correspond to more probable regions of the space, that is, to Galactic coordinates crossed more frequently by the simulated orbits. As is apparent, the larger distances reached by the system during its evolution are R = 3.5 kpc and \n\n\n\n\n\n kpc at a 3σ level of significance, which roughly correspond to a region having the current size of the bulge.","Citation Text":["Hockney & Eastwood 1988"],"Citation Start End":[[1279,1302]]} {"Identifier":"2022ApJ...930..125L__Cartwright_&_Moldwin_2010_Instance_1","Paragraph":"A scenario that could potentially support superdiffusive parallel transport for energetic ions interacting with SMFRs in the large-scale solar wind is when (1) these structures can be viewed as coherent, quasi-helical magnetic field structures with a typical width L\n\nI\n of intermediate size and sharp boundaries (Greco et al. 2009), and (2) energetic particles have gyroradii r\n\ng\n that are small compared to the typical SMFR width L\n\nI\n. There is observational support at 1 au for all these assumptions (e.g., Greco et al. 2009; Cartwright & Moldwin 2010; le Roux et al. 2015). Thus, it is reasonable to envisage that the particle guiding centers follow the helical magnetic field lines (negligible cross-field drifts) to propagate through SMFR structures in a coherent fashion for a considerable distance before scattering during exit of the structure through the narrow magnetic boundaries. To be more specific, SMFRs identified at 1 au typically have widths L\n\nI\n ≈ 0.01 − 0.001 au (Cartwright & Moldwin 2010; Khabarova et al. 2015), while data analysis of low-frequency 2D turbulence suggests elongated SMFR structures with an average length L\n\nI∣∣ so that L\n\nI∣∣\/L\n\nI\n ≈ 2 − 3 (Weygand et al. 2011). Based on the expression for the path length s\n\nI\n of a SMFR helical field line (Equation (9)), we estimate that the distance a particle guiding center travel through a SMFR structure by following magnetic field lines can be considerable because s\n\nI\n ≈ 0.004 − 0.04 au. Furthermore, the protons accelerated by SMFRs reach kinetic energies of ≲5 MeV (Khabarova & Zank 2017) in the solar wind at 1 au, thus easily fulfilling the requirement r\n\ng\n ≪ L\n\nI\n. Consequently, the transport through SMFRs can be characterized as involving an enhanced probability of relatively long transport distances or step sizes along the background\/guide field perpendicular to the shock surface (in the z-direction) between scattering events indicating Lévy walks as discussed by Zimbardo & Perri (2020) and Zimbardo et al. (2021).","Citation Text":["Cartwright & Moldwin 2010"],"Citation Start End":[[531,556]]} {"Identifier":"2022ApJ...930..125L__Cartwright_&_Moldwin_2010_Instance_2","Paragraph":"A scenario that could potentially support superdiffusive parallel transport for energetic ions interacting with SMFRs in the large-scale solar wind is when (1) these structures can be viewed as coherent, quasi-helical magnetic field structures with a typical width L\n\nI\n of intermediate size and sharp boundaries (Greco et al. 2009), and (2) energetic particles have gyroradii r\n\ng\n that are small compared to the typical SMFR width L\n\nI\n. There is observational support at 1 au for all these assumptions (e.g., Greco et al. 2009; Cartwright & Moldwin 2010; le Roux et al. 2015). Thus, it is reasonable to envisage that the particle guiding centers follow the helical magnetic field lines (negligible cross-field drifts) to propagate through SMFR structures in a coherent fashion for a considerable distance before scattering during exit of the structure through the narrow magnetic boundaries. To be more specific, SMFRs identified at 1 au typically have widths L\n\nI\n ≈ 0.01 − 0.001 au (Cartwright & Moldwin 2010; Khabarova et al. 2015), while data analysis of low-frequency 2D turbulence suggests elongated SMFR structures with an average length L\n\nI∣∣ so that L\n\nI∣∣\/L\n\nI\n ≈ 2 − 3 (Weygand et al. 2011). Based on the expression for the path length s\n\nI\n of a SMFR helical field line (Equation (9)), we estimate that the distance a particle guiding center travel through a SMFR structure by following magnetic field lines can be considerable because s\n\nI\n ≈ 0.004 − 0.04 au. Furthermore, the protons accelerated by SMFRs reach kinetic energies of ≲5 MeV (Khabarova & Zank 2017) in the solar wind at 1 au, thus easily fulfilling the requirement r\n\ng\n ≪ L\n\nI\n. Consequently, the transport through SMFRs can be characterized as involving an enhanced probability of relatively long transport distances or step sizes along the background\/guide field perpendicular to the shock surface (in the z-direction) between scattering events indicating Lévy walks as discussed by Zimbardo & Perri (2020) and Zimbardo et al. (2021).","Citation Text":["Cartwright & Moldwin 2010"],"Citation Start End":[[988,1013]]} {"Identifier":"2017ApJ...848...51D__André_et_al._2010_Instance_2","Paragraph":"In recent years, there has been an increasing interest in identifying embedded filaments at an early stage of fragmentation, where star formation activities have not yet started. Kainulainen et al. (2016) studied the Musca molecular cloud using the NIR, 870 μm dust continuum and molecular line data, and suggested that the Musca cloud is a very promising candidate for a filament at an early stage of fragmentation and shows very few signs of ongoing star formation. However, the identification of such filaments is still limited in the literature (e.g., Kainulainen et al. 2016). In the I05463+2652 site, we have selected two elongated filamentary features (“s-fl” and “nw-fl”). The Herschel temperature map reveals these filaments with a temperature of ∼11 K. It has been suggested that the thermally supercritical filaments (i.e., \n\n\n\n\n\n\nM\n\n\nline\n\n\n>\n\n\nM\n\n\nline\n,\ncrit\n\n\n\n\n) can be unstable to radial collapse and fragmentation (André et al. 2010). However, thermally subcritical filaments (i.e., \n\n\n\n\n\n\nM\n\n\nline\n\n\n\n\n\nM\n\n\nline\n,\ncrit\n\n\n\n\n) may lack prestellar clumps\/cores and embedded protostars (André et al. 2010). In the I05463+2652 site, the observed masses per unit length of the filaments are computed to be \n\n\n\n\n∼\n60\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1 (for filament “s-fl”) and \n\n\n\n\n∼\n200\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1 (for filament “nw-fl”), which are much higher than the critical mass per unit length at T = 10 K (i.e., \n\n\n\n\n\n\nM\n\n\nline\n,\ncrit\n\n\n=\n16\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1; see Section 3.2). For the purpose of comparison, we also provide the observed masses per unit length of some well known filaments (such as DR21 (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n4500\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1), Serpens South (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n290\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1), Taurus B211\/B213 (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n50\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1), and Musca (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n20\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1)) (see Table 1 in André et al. 2016). Based on the analysis of masses per unit length, the elongated filaments (“s-fl” and “nw-fl”) are thermally supercritical (see Section 3.2). Furthermore, these two filaments contain clumps (or fragments), indicating the signature of gravitational fragmentation. Arzoumanian et al. (2013) pointed out that supercritical filaments may undergo gravitational contraction and increase in mass per unit length through the accretion of background material.","Citation Text":["André et al. 2010"],"Citation Start End":[[1102,1119]]} {"Identifier":"2017ApJ...848...51D__André_et_al._2010_Instance_1","Paragraph":"In recent years, there has been an increasing interest in identifying embedded filaments at an early stage of fragmentation, where star formation activities have not yet started. Kainulainen et al. (2016) studied the Musca molecular cloud using the NIR, 870 μm dust continuum and molecular line data, and suggested that the Musca cloud is a very promising candidate for a filament at an early stage of fragmentation and shows very few signs of ongoing star formation. However, the identification of such filaments is still limited in the literature (e.g., Kainulainen et al. 2016). In the I05463+2652 site, we have selected two elongated filamentary features (“s-fl” and “nw-fl”). The Herschel temperature map reveals these filaments with a temperature of ∼11 K. It has been suggested that the thermally supercritical filaments (i.e., \n\n\n\n\n\n\nM\n\n\nline\n\n\n>\n\n\nM\n\n\nline\n,\ncrit\n\n\n\n\n) can be unstable to radial collapse and fragmentation (André et al. 2010). However, thermally subcritical filaments (i.e., \n\n\n\n\n\n\nM\n\n\nline\n\n\n\n\n\nM\n\n\nline\n,\ncrit\n\n\n\n\n) may lack prestellar clumps\/cores and embedded protostars (André et al. 2010). In the I05463+2652 site, the observed masses per unit length of the filaments are computed to be \n\n\n\n\n∼\n60\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1 (for filament “s-fl”) and \n\n\n\n\n∼\n200\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1 (for filament “nw-fl”), which are much higher than the critical mass per unit length at T = 10 K (i.e., \n\n\n\n\n\n\nM\n\n\nline\n,\ncrit\n\n\n=\n16\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1; see Section 3.2). For the purpose of comparison, we also provide the observed masses per unit length of some well known filaments (such as DR21 (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n4500\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1), Serpens South (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n290\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1), Taurus B211\/B213 (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n50\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1), and Musca (\n\n\n\n\n\n\nM\n\n\nline\n\n\n∼\n20\n\n\n\nM\n\n\n⊙\n\n\n\n\n pc−1)) (see Table 1 in André et al. 2016). Based on the analysis of masses per unit length, the elongated filaments (“s-fl” and “nw-fl”) are thermally supercritical (see Section 3.2). Furthermore, these two filaments contain clumps (or fragments), indicating the signature of gravitational fragmentation. Arzoumanian et al. (2013) pointed out that supercritical filaments may undergo gravitational contraction and increase in mass per unit length through the accretion of background material.","Citation Text":["André et al. 2010"],"Citation Start End":[[933,950]]} {"Identifier":"2020MNRAS.496.5243H__Wilson_et_al._2019_Instance_1","Paragraph":"One of the theoretical models to account for different depletion times is the turbulence model of Krumholz & McKee (2005). According to this model, turbulence will determine the density PDF of the clouds. The most important parameter is the SFE per free-fall time, which is the ratio between the free-fall time and the depletion time. The general equation for free-fall time is\n(15)$$\\begin{eqnarray*}\r\nt_{\\text{ff}}=\\sqrt{\\frac{3\\pi }{32G\\rho _{\\mathrm{mol, mid}}}},\r\n\\end{eqnarray*}$$where ρmol, mid is the volume density of the molecular gas in the middle of the disc. If we assume the galaxy is filled with gas, then the volume density can be calculated as\n(16)$$\\begin{eqnarray*}\r\n\\rho _{\\mathrm{mol, mid}}=\\frac{\\Sigma _{\\text{mol}}}{2 H_{\\mathrm{mol}}} ,\r\n\\end{eqnarray*}$$where Hmol is the scale height of the disc and Σmol is the surface density of the molecular gas measured from the 12CO J = 2–1 cube (see Section 3.2). Assuming the gas disc is in equilibrium and that vertical gravity is dominated by gas self-gravity, then we can calculate the scale height as (Wilson et al. 2019)\n(17)$$\\begin{eqnarray*}\r\nH_{\\mathrm{mol}}= 0.5\\frac{\\sigma _v^2}{\\pi G \\Sigma _{\\text{mol}}} ,\r\n\\end{eqnarray*}$$where σv is the velocity dispersion of the molecular gas. Combining all the equations above, we can write the free-fall time as\n(18)$$\\begin{eqnarray*}\r\nt_{\\text{ff}}=\\frac{\\sqrt{3}}{4G} \\frac{\\sigma _v}{\\Sigma _{\\text{mol}}} .\r\n\\end{eqnarray*}$$Therefore, the SFE per free-fall time can be calculated as (Wilson et al. 2019)\n(19)$$\\begin{eqnarray*}\r\n\\epsilon _{\\text{ff}}=\\frac{t_{\\text{ff}}}{t_{\\text{dep}}}=\\frac{\\sqrt{3}}{4G}\\frac{\\sigma _v \\Sigma _{\\text{SFR}}}{\\Sigma ^2_{\\mathrm{mol}}} .\r\n\\end{eqnarray*}$$Assuming a constant SFE per free-fall time, the depletion time will decrease as the surface density of the gas increases. To calculate ϵff, we need maps of Σmol, ΣSFR, and σv. We plot ϵff versus Σmol in Fig. 11 (left plot). As we can see, there is a clear decreasing trend for ϵff versus Σmol for Arp 240, while ϵff stays relatively constant for the other U\/LIRGs. Furthermore, in the low surface density regions, ϵff can be above 1.0. For normal clouds, ϵff can be as high as several 10 per cent (Lee et al. 2016). Therefore, our method probably overestimates the true efficiency in these galaxies.","Citation Text":["Wilson et al. 2019"],"Citation Start End":[[1074,1092]]} {"Identifier":"2020MNRAS.496.5243H__Wilson_et_al._2019_Instance_2","Paragraph":"One of the theoretical models to account for different depletion times is the turbulence model of Krumholz & McKee (2005). According to this model, turbulence will determine the density PDF of the clouds. The most important parameter is the SFE per free-fall time, which is the ratio between the free-fall time and the depletion time. The general equation for free-fall time is\n(15)$$\\begin{eqnarray*}\r\nt_{\\text{ff}}=\\sqrt{\\frac{3\\pi }{32G\\rho _{\\mathrm{mol, mid}}}},\r\n\\end{eqnarray*}$$where ρmol, mid is the volume density of the molecular gas in the middle of the disc. If we assume the galaxy is filled with gas, then the volume density can be calculated as\n(16)$$\\begin{eqnarray*}\r\n\\rho _{\\mathrm{mol, mid}}=\\frac{\\Sigma _{\\text{mol}}}{2 H_{\\mathrm{mol}}} ,\r\n\\end{eqnarray*}$$where Hmol is the scale height of the disc and Σmol is the surface density of the molecular gas measured from the 12CO J = 2–1 cube (see Section 3.2). Assuming the gas disc is in equilibrium and that vertical gravity is dominated by gas self-gravity, then we can calculate the scale height as (Wilson et al. 2019)\n(17)$$\\begin{eqnarray*}\r\nH_{\\mathrm{mol}}= 0.5\\frac{\\sigma _v^2}{\\pi G \\Sigma _{\\text{mol}}} ,\r\n\\end{eqnarray*}$$where σv is the velocity dispersion of the molecular gas. Combining all the equations above, we can write the free-fall time as\n(18)$$\\begin{eqnarray*}\r\nt_{\\text{ff}}=\\frac{\\sqrt{3}}{4G} \\frac{\\sigma _v}{\\Sigma _{\\text{mol}}} .\r\n\\end{eqnarray*}$$Therefore, the SFE per free-fall time can be calculated as (Wilson et al. 2019)\n(19)$$\\begin{eqnarray*}\r\n\\epsilon _{\\text{ff}}=\\frac{t_{\\text{ff}}}{t_{\\text{dep}}}=\\frac{\\sqrt{3}}{4G}\\frac{\\sigma _v \\Sigma _{\\text{SFR}}}{\\Sigma ^2_{\\mathrm{mol}}} .\r\n\\end{eqnarray*}$$Assuming a constant SFE per free-fall time, the depletion time will decrease as the surface density of the gas increases. To calculate ϵff, we need maps of Σmol, ΣSFR, and σv. We plot ϵff versus Σmol in Fig. 11 (left plot). As we can see, there is a clear decreasing trend for ϵff versus Σmol for Arp 240, while ϵff stays relatively constant for the other U\/LIRGs. Furthermore, in the low surface density regions, ϵff can be above 1.0. For normal clouds, ϵff can be as high as several 10 per cent (Lee et al. 2016). Therefore, our method probably overestimates the true efficiency in these galaxies.","Citation Text":["Wilson et al. 2019"],"Citation Start End":[[1513,1531]]} {"Identifier":"2017MNRAS.464.1192M__Cai_2007_Instance_1","Paragraph":"Since the HDE model is obtained by choosing the event horizon length-scale, an obvious drawback concerning causality appears in this scenario. Recently, a new DE model, dubbed agegraphic dark energy (ADE) model, has been suggested by Cai (2007) in order to alleviate the above problem. In particular, combining the uncertainty principle in quantum mechanics and the gravitational effects of GR Karolyhazy and his collaborators (Karolyhazy 1966; Karolyhazy & Lukacs 1982, 1986) made an interesting observation concerning the distance measurement for the Minkowski space–time through a light-clock Gedanken experiment (see also Maziashvili 2007a). They found that the distance t in Minkowski space–time cannot be known to a better accuracy than $\\delta t=\\beta t_{\\rm p}^{2\/3}t^{1\/3}$, where β is a dimensionless constant of the order of ${\\cal O}(1)$ (see also Maziashvili 2007a).1 Based on the Karolyhazy relation, Maziashvili (2007a) argued that the energy density of metric fluctuations in the Minkowski space–time is written as (see also Maziashvili 2007b)\n\n(2)\n\n\\begin{equation}\n\\rho _{{\\rm d}}\\sim \\frac{1}{t_{{\\rm p}}^{2}t^{2}}\\sim \\frac{m_{{\\rm p}}}{t^{2}},\n\\end{equation}\n\nwhere mp and tp are the reduced Plank mass and the Plank time, respectively (see also Ng & Van Dam 1994, 1995; Sasakura 1999; Krauss & Turner 2004; Christiansen, Ng & van Dam 2006; Arzano, Kephart & Ng 2007; Ng 2007). Using equation (2), Cai (2007) proposed another version of holographic DE, the so-called ADE, in which the time-scale t is chosen to be equal with the age of the universe $T= \\int ^{t}_0{\\rm d}t=\\int _{0}^{a}\\frac{{\\rm d}a}{aH}$, with a the scalefactor of the universe and H the Hubble parameter. Therefore, the ADE energy density is given by (Cai 2007)\n\n(3)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{T^{2}},\n\\end{equation}\n\nwhere n is a free parameter and the coefficient 3 appears for convenience. The present value of the age of universe ($T_{\\rm 0}\\sim H_{\\rm 0}^{-1}$) implies that n is of the order of ${\\cal O}(1)$. It has been shown that the condition n > 1 is required in order to have cosmic acceleration (Cai 2007). Although, the ADE scenario does not suffer from the causality problem (Cai 2007), it faces some problems towards describing the matter-dominated epoch (Neupane 2007; Wei & Cai 2008a,b). To overcome this issue, Wei & Cai (2008a) proposed a new agegraphic dark energy (NADE) model, in which the cosmic time t is replaced by the conformal time $\\eta = \\int ^{t}_0{\\frac{{\\rm d}t}{a(t)}}=\\int ^{a}_0{\\frac{{\\rm d}a}{a^{2}H}}$ and thus the energy density in this case becomes (Wei & Cai 2008a)\n\n(4)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{\\eta ^{2}}.\n\\end{equation}\n\nIt is interesting to mention that Kim, Lee & Myung (2008b) showed that the NADE model provides the proper matter-dominated and radiation-dominated epochs, in the case of n > 2.68 and n > 2.51, respectively. Also, Wei & Cai (2008b) found that the coincidence problem can be alleviated naturally in this model and using the cosmological data (SNIa, CMB, etc.), they obtained $n=2.716^{+0.111}_{-0.109}$. We would like to point out that the cosmological properties of the ADE and the NADE models can be found in Kim et al. (2008a), Setare & Jamil (2011), Karami et al. (2011), Sheykhi & Setare (2010), Sheykhi (2009), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2010c), Lee, Kim & Myung (2008), Jawad, Chattopadhyay & Pasqua (2013), Liu et al. (2012), Zhang, Li & Zhang (2013), Farajollahi, Ravanpak & Fadakar (2012), Zhai, Zhang & Liu (2011), Chen et al. (2011), Sun & Yue (2011), Lemets, Yerokhin & Zazunov (2011), Zhang, Zhang & Zhang (2010), Liu, Zhang & Zhang (2010), Karami & Khaledian (2011), Malekjani & Khodam-Mohammadi (2010), Jamil & Saridakis (2010), Karami et al. (2010), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2009), Wu, Ma & Ling (2008), Zhang, Zhang & Liu (2008), Kim et al. (2008b), Neupane (2009) and Wei & Cai (2008b).","Citation Text":["Cai (2007)"],"Citation Start End":[[234,244]]} {"Identifier":"2017MNRAS.464.1192M__Cai_2007_Instance_2","Paragraph":"Since the HDE model is obtained by choosing the event horizon length-scale, an obvious drawback concerning causality appears in this scenario. Recently, a new DE model, dubbed agegraphic dark energy (ADE) model, has been suggested by Cai (2007) in order to alleviate the above problem. In particular, combining the uncertainty principle in quantum mechanics and the gravitational effects of GR Karolyhazy and his collaborators (Karolyhazy 1966; Karolyhazy & Lukacs 1982, 1986) made an interesting observation concerning the distance measurement for the Minkowski space–time through a light-clock Gedanken experiment (see also Maziashvili 2007a). They found that the distance t in Minkowski space–time cannot be known to a better accuracy than $\\delta t=\\beta t_{\\rm p}^{2\/3}t^{1\/3}$, where β is a dimensionless constant of the order of ${\\cal O}(1)$ (see also Maziashvili 2007a).1 Based on the Karolyhazy relation, Maziashvili (2007a) argued that the energy density of metric fluctuations in the Minkowski space–time is written as (see also Maziashvili 2007b)\n\n(2)\n\n\\begin{equation}\n\\rho _{{\\rm d}}\\sim \\frac{1}{t_{{\\rm p}}^{2}t^{2}}\\sim \\frac{m_{{\\rm p}}}{t^{2}},\n\\end{equation}\n\nwhere mp and tp are the reduced Plank mass and the Plank time, respectively (see also Ng & Van Dam 1994, 1995; Sasakura 1999; Krauss & Turner 2004; Christiansen, Ng & van Dam 2006; Arzano, Kephart & Ng 2007; Ng 2007). Using equation (2), Cai (2007) proposed another version of holographic DE, the so-called ADE, in which the time-scale t is chosen to be equal with the age of the universe $T= \\int ^{t}_0{\\rm d}t=\\int _{0}^{a}\\frac{{\\rm d}a}{aH}$, with a the scalefactor of the universe and H the Hubble parameter. Therefore, the ADE energy density is given by (Cai 2007)\n\n(3)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{T^{2}},\n\\end{equation}\n\nwhere n is a free parameter and the coefficient 3 appears for convenience. The present value of the age of universe ($T_{\\rm 0}\\sim H_{\\rm 0}^{-1}$) implies that n is of the order of ${\\cal O}(1)$. It has been shown that the condition n > 1 is required in order to have cosmic acceleration (Cai 2007). Although, the ADE scenario does not suffer from the causality problem (Cai 2007), it faces some problems towards describing the matter-dominated epoch (Neupane 2007; Wei & Cai 2008a,b). To overcome this issue, Wei & Cai (2008a) proposed a new agegraphic dark energy (NADE) model, in which the cosmic time t is replaced by the conformal time $\\eta = \\int ^{t}_0{\\frac{{\\rm d}t}{a(t)}}=\\int ^{a}_0{\\frac{{\\rm d}a}{a^{2}H}}$ and thus the energy density in this case becomes (Wei & Cai 2008a)\n\n(4)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{\\eta ^{2}}.\n\\end{equation}\n\nIt is interesting to mention that Kim, Lee & Myung (2008b) showed that the NADE model provides the proper matter-dominated and radiation-dominated epochs, in the case of n > 2.68 and n > 2.51, respectively. Also, Wei & Cai (2008b) found that the coincidence problem can be alleviated naturally in this model and using the cosmological data (SNIa, CMB, etc.), they obtained $n=2.716^{+0.111}_{-0.109}$. We would like to point out that the cosmological properties of the ADE and the NADE models can be found in Kim et al. (2008a), Setare & Jamil (2011), Karami et al. (2011), Sheykhi & Setare (2010), Sheykhi (2009), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2010c), Lee, Kim & Myung (2008), Jawad, Chattopadhyay & Pasqua (2013), Liu et al. (2012), Zhang, Li & Zhang (2013), Farajollahi, Ravanpak & Fadakar (2012), Zhai, Zhang & Liu (2011), Chen et al. (2011), Sun & Yue (2011), Lemets, Yerokhin & Zazunov (2011), Zhang, Zhang & Zhang (2010), Liu, Zhang & Zhang (2010), Karami & Khaledian (2011), Malekjani & Khodam-Mohammadi (2010), Jamil & Saridakis (2010), Karami et al. (2010), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2009), Wu, Ma & Ling (2008), Zhang, Zhang & Liu (2008), Kim et al. (2008b), Neupane (2009) and Wei & Cai (2008b).","Citation Text":["Cai (2007)"],"Citation Start End":[[1419,1429]]} {"Identifier":"2017MNRAS.464.1192M__Cai_2007_Instance_3","Paragraph":"Since the HDE model is obtained by choosing the event horizon length-scale, an obvious drawback concerning causality appears in this scenario. Recently, a new DE model, dubbed agegraphic dark energy (ADE) model, has been suggested by Cai (2007) in order to alleviate the above problem. In particular, combining the uncertainty principle in quantum mechanics and the gravitational effects of GR Karolyhazy and his collaborators (Karolyhazy 1966; Karolyhazy & Lukacs 1982, 1986) made an interesting observation concerning the distance measurement for the Minkowski space–time through a light-clock Gedanken experiment (see also Maziashvili 2007a). They found that the distance t in Minkowski space–time cannot be known to a better accuracy than $\\delta t=\\beta t_{\\rm p}^{2\/3}t^{1\/3}$, where β is a dimensionless constant of the order of ${\\cal O}(1)$ (see also Maziashvili 2007a).1 Based on the Karolyhazy relation, Maziashvili (2007a) argued that the energy density of metric fluctuations in the Minkowski space–time is written as (see also Maziashvili 2007b)\n\n(2)\n\n\\begin{equation}\n\\rho _{{\\rm d}}\\sim \\frac{1}{t_{{\\rm p}}^{2}t^{2}}\\sim \\frac{m_{{\\rm p}}}{t^{2}},\n\\end{equation}\n\nwhere mp and tp are the reduced Plank mass and the Plank time, respectively (see also Ng & Van Dam 1994, 1995; Sasakura 1999; Krauss & Turner 2004; Christiansen, Ng & van Dam 2006; Arzano, Kephart & Ng 2007; Ng 2007). Using equation (2), Cai (2007) proposed another version of holographic DE, the so-called ADE, in which the time-scale t is chosen to be equal with the age of the universe $T= \\int ^{t}_0{\\rm d}t=\\int _{0}^{a}\\frac{{\\rm d}a}{aH}$, with a the scalefactor of the universe and H the Hubble parameter. Therefore, the ADE energy density is given by (Cai 2007)\n\n(3)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{T^{2}},\n\\end{equation}\n\nwhere n is a free parameter and the coefficient 3 appears for convenience. The present value of the age of universe ($T_{\\rm 0}\\sim H_{\\rm 0}^{-1}$) implies that n is of the order of ${\\cal O}(1)$. It has been shown that the condition n > 1 is required in order to have cosmic acceleration (Cai 2007). Although, the ADE scenario does not suffer from the causality problem (Cai 2007), it faces some problems towards describing the matter-dominated epoch (Neupane 2007; Wei & Cai 2008a,b). To overcome this issue, Wei & Cai (2008a) proposed a new agegraphic dark energy (NADE) model, in which the cosmic time t is replaced by the conformal time $\\eta = \\int ^{t}_0{\\frac{{\\rm d}t}{a(t)}}=\\int ^{a}_0{\\frac{{\\rm d}a}{a^{2}H}}$ and thus the energy density in this case becomes (Wei & Cai 2008a)\n\n(4)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{\\eta ^{2}}.\n\\end{equation}\n\nIt is interesting to mention that Kim, Lee & Myung (2008b) showed that the NADE model provides the proper matter-dominated and radiation-dominated epochs, in the case of n > 2.68 and n > 2.51, respectively. Also, Wei & Cai (2008b) found that the coincidence problem can be alleviated naturally in this model and using the cosmological data (SNIa, CMB, etc.), they obtained $n=2.716^{+0.111}_{-0.109}$. We would like to point out that the cosmological properties of the ADE and the NADE models can be found in Kim et al. (2008a), Setare & Jamil (2011), Karami et al. (2011), Sheykhi & Setare (2010), Sheykhi (2009), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2010c), Lee, Kim & Myung (2008), Jawad, Chattopadhyay & Pasqua (2013), Liu et al. (2012), Zhang, Li & Zhang (2013), Farajollahi, Ravanpak & Fadakar (2012), Zhai, Zhang & Liu (2011), Chen et al. (2011), Sun & Yue (2011), Lemets, Yerokhin & Zazunov (2011), Zhang, Zhang & Zhang (2010), Liu, Zhang & Zhang (2010), Karami & Khaledian (2011), Malekjani & Khodam-Mohammadi (2010), Jamil & Saridakis (2010), Karami et al. (2010), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2009), Wu, Ma & Ling (2008), Zhang, Zhang & Liu (2008), Kim et al. (2008b), Neupane (2009) and Wei & Cai (2008b).","Citation Text":["Cai 2007"],"Citation Start End":[[1743,1751]]} {"Identifier":"2017MNRAS.464.1192M__Cai_2007_Instance_4","Paragraph":"Since the HDE model is obtained by choosing the event horizon length-scale, an obvious drawback concerning causality appears in this scenario. Recently, a new DE model, dubbed agegraphic dark energy (ADE) model, has been suggested by Cai (2007) in order to alleviate the above problem. In particular, combining the uncertainty principle in quantum mechanics and the gravitational effects of GR Karolyhazy and his collaborators (Karolyhazy 1966; Karolyhazy & Lukacs 1982, 1986) made an interesting observation concerning the distance measurement for the Minkowski space–time through a light-clock Gedanken experiment (see also Maziashvili 2007a). They found that the distance t in Minkowski space–time cannot be known to a better accuracy than $\\delta t=\\beta t_{\\rm p}^{2\/3}t^{1\/3}$, where β is a dimensionless constant of the order of ${\\cal O}(1)$ (see also Maziashvili 2007a).1 Based on the Karolyhazy relation, Maziashvili (2007a) argued that the energy density of metric fluctuations in the Minkowski space–time is written as (see also Maziashvili 2007b)\n\n(2)\n\n\\begin{equation}\n\\rho _{{\\rm d}}\\sim \\frac{1}{t_{{\\rm p}}^{2}t^{2}}\\sim \\frac{m_{{\\rm p}}}{t^{2}},\n\\end{equation}\n\nwhere mp and tp are the reduced Plank mass and the Plank time, respectively (see also Ng & Van Dam 1994, 1995; Sasakura 1999; Krauss & Turner 2004; Christiansen, Ng & van Dam 2006; Arzano, Kephart & Ng 2007; Ng 2007). Using equation (2), Cai (2007) proposed another version of holographic DE, the so-called ADE, in which the time-scale t is chosen to be equal with the age of the universe $T= \\int ^{t}_0{\\rm d}t=\\int _{0}^{a}\\frac{{\\rm d}a}{aH}$, with a the scalefactor of the universe and H the Hubble parameter. Therefore, the ADE energy density is given by (Cai 2007)\n\n(3)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{T^{2}},\n\\end{equation}\n\nwhere n is a free parameter and the coefficient 3 appears for convenience. The present value of the age of universe ($T_{\\rm 0}\\sim H_{\\rm 0}^{-1}$) implies that n is of the order of ${\\cal O}(1)$. It has been shown that the condition n > 1 is required in order to have cosmic acceleration (Cai 2007). Although, the ADE scenario does not suffer from the causality problem (Cai 2007), it faces some problems towards describing the matter-dominated epoch (Neupane 2007; Wei & Cai 2008a,b). To overcome this issue, Wei & Cai (2008a) proposed a new agegraphic dark energy (NADE) model, in which the cosmic time t is replaced by the conformal time $\\eta = \\int ^{t}_0{\\frac{{\\rm d}t}{a(t)}}=\\int ^{a}_0{\\frac{{\\rm d}a}{a^{2}H}}$ and thus the energy density in this case becomes (Wei & Cai 2008a)\n\n(4)\n\n\\begin{equation}\n\\rho _{{\\rm d}}=\\frac{3n^{2}m_{{\\rm p}}^{2}}{\\eta ^{2}}.\n\\end{equation}\n\nIt is interesting to mention that Kim, Lee & Myung (2008b) showed that the NADE model provides the proper matter-dominated and radiation-dominated epochs, in the case of n > 2.68 and n > 2.51, respectively. Also, Wei & Cai (2008b) found that the coincidence problem can be alleviated naturally in this model and using the cosmological data (SNIa, CMB, etc.), they obtained $n=2.716^{+0.111}_{-0.109}$. We would like to point out that the cosmological properties of the ADE and the NADE models can be found in Kim et al. (2008a), Setare & Jamil (2011), Karami et al. (2011), Sheykhi & Setare (2010), Sheykhi (2009), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2010c), Lee, Kim & Myung (2008), Jawad, Chattopadhyay & Pasqua (2013), Liu et al. (2012), Zhang, Li & Zhang (2013), Farajollahi, Ravanpak & Fadakar (2012), Zhai, Zhang & Liu (2011), Chen et al. (2011), Sun & Yue (2011), Lemets, Yerokhin & Zazunov (2011), Zhang, Zhang & Zhang (2010), Liu, Zhang & Zhang (2010), Karami & Khaledian (2011), Malekjani & Khodam-Mohammadi (2010), Jamil & Saridakis (2010), Karami et al. (2010), Sheykhi (2010a), Sheykhi (2010b), Sheykhi (2009), Wu, Ma & Ling (2008), Zhang, Zhang & Liu (2008), Kim et al. (2008b), Neupane (2009) and Wei & Cai (2008b).","Citation Text":["Cai 2007"],"Citation Start End":[[2218,2226]]} {"Identifier":"2020ApJ...899..145Y__Zhang_et_al._2017_Instance_1","Paragraph":"As mentioned in Sections 2, six sources (G035.19–00.74, G049.48–00.36, G133.94+01.06, G031.28+00.06, G043.89–00.78 and G059.78+00.06) were observed by both the ARO 12 m and IRAM 30 m telescopes, which can be used to check beam size effects potentially influencing our abundance ratios. A comparison between the spectra from the ARO 12 m and the IRAM 30 m is shown in Figure 3. Measured line parameters are given in Tables 1 and 2. If the scale of our targets is smaller than the beam size, filling factors are less than unity. So, measured line intensities are diluted. In this case, the intensity of detected lines has to be adjusted for the beam dilution effect \n\n\n\n\n\n\/(\n\n\n\n\n\n + \n\n\n\n\n\n) (ηBD), where θs and θbeam are source size and beam size, respectively (Zhang et al. 2017). Thus, the brightness temperatures (TB) of the sources can be derived from the main beam brightness temperature (Tmb) dilution:\n5\n\n\n\n\n\nThere are two Tmb values, measured by the IRAM 30 m and the ARO 12 m with beam sizes of ∼25″ and ∼63″. Therefore, the source size can be estimated using Equation (5). We employed CS, C34S, 13CS, and C33S line data to estimate the size of those six sources, and the results are listed in Table 4. Source sizes turn out to be in the range 24″–126″ and are quite different between estimations from different isotopes. To the contrary, the sulfur isotope abundance ratios do not show significant differences between the ARO 12 m and the IRAM 30 m measurements. Within the error ranges, the average abundance ratios determined from the ARO 12 m (17.6 ± 2.7 and 4.9 ± 0.7 for 32S\/34S and 34S\/33S, respectively) are consistent with those from the IRAM 30 m observations (18.1 ± 4.1 and 5.5 ± 0.8; the errors given in this subsection represent standard deviations for individual sources). In addition, two sources (Sgr B2, G111.54+00.77 (NGC 7538)) among our sample were also observed by the 7 m antenna of the Crawford Hill Observatory (Frerking et al. 1980). The I(13CS)\/I(C34S) line intensity ratios measured by Frerking et al. (1980) yield 0.62 ± 0.04 and 0.43 ± 0.3 with a beam size of ∼22, which is also consistent with our results from the ARO 12 m (0.60 ± 0.03 and 0.38 ± 0.04). Thus, our measurements of sulfur isotope ratios are not seriously affected by beam size effects.","Citation Text":["Zhang et al. 2017"],"Citation Start End":[[760,777]]} {"Identifier":"2018MNRAS.475.4891M__Hulst_2016_Instance_1","Paragraph":"For all galaxies the extended profiles of $\\Sigma _\\mathrm{H\\,\\small {I}}$ obtained from observations at the WSRT telescope were found in Yim & van der Hulst (2016) and Noordermeer et al. (2005). The surface density of $\\Sigma _\\mathrm{H_2}$ is usually calculated from observations of CO molecule lines, but the exact value of the conversion factor XCO remains debatable. If CO intensity profile is available, we follow the procedure described in Yim & van der Hulst (2016) to obtain $\\Sigma _\\mathrm{H_2}$. For NGC 4258, NGC 4725 (Yim & van der Hulst 2016), and NGC 2985 (Young et al. 1995), the CO(J = 1 → 0) line was used to calculate $\\Sigma _\\mathrm{H_2}$:\n\r\n\\begin{equation*}\r\n\\Sigma _\\mathrm{H_2} (\\text{M}_{\\odot }\\,\\mathrm{pc}^{-2}) = 3.2\\times I_\\mathrm{CO}(\\mathrm{K\\,km\\,s^{-1}})\\,.\r\n\\end{equation*}\r\nHowever, for three of four remaining galaxies only the total mass of molecular hydrogen $M_\\mathrm{H_2}$ was found. Regan et al. (2001) make a conclusion based on the BIMA survey data that $\\Sigma _\\mathrm{H_2}(R)$ profile decreases exponentially with a scale equal to the scale length of the disc h on the average. Therefore for these remaining galaxies we found central surface densities from the formula of the total mass of the molecular disc $\\displaystyle \\Sigma _\\mathrm{H_2}(0) = \\frac{M_\\mathrm{H_2}}{2 {\\pi} \\, h^2}$ and then extended them exponentially with the appropriate h scale length. If more than one photometry is used for an examined galaxy this approach gives several possible profiles of $\\Sigma _\\mathrm{H_2}(R)$ and several estimates of Q, respectively both for one-fluid and two-component cases. We approximate the $\\Sigma _\\mathrm{H_2}(R)$ and $\\Sigma _\\mathrm{H\\, \\small {I}}(R)$ profiles using linear interpolation between points. The total gas surface density was corrected for the presence of helium and other heavy elements using $\\Sigma _\\mathrm{g} = 1.36\\,(\\Sigma _\\mathrm{H\\,\\small {I}} + \\Sigma _\\mathrm{H_2})$ formula (see for example Leroy et al. 2008).","Citation Text":["Yim & van der Hulst (2016)"],"Citation Start End":[[138,164]]} {"Identifier":"2018MNRAS.475.4891M__Hulst_2016_Instance_2","Paragraph":"For all galaxies the extended profiles of $\\Sigma _\\mathrm{H\\,\\small {I}}$ obtained from observations at the WSRT telescope were found in Yim & van der Hulst (2016) and Noordermeer et al. (2005). The surface density of $\\Sigma _\\mathrm{H_2}$ is usually calculated from observations of CO molecule lines, but the exact value of the conversion factor XCO remains debatable. If CO intensity profile is available, we follow the procedure described in Yim & van der Hulst (2016) to obtain $\\Sigma _\\mathrm{H_2}$. For NGC 4258, NGC 4725 (Yim & van der Hulst 2016), and NGC 2985 (Young et al. 1995), the CO(J = 1 → 0) line was used to calculate $\\Sigma _\\mathrm{H_2}$:\n\r\n\\begin{equation*}\r\n\\Sigma _\\mathrm{H_2} (\\text{M}_{\\odot }\\,\\mathrm{pc}^{-2}) = 3.2\\times I_\\mathrm{CO}(\\mathrm{K\\,km\\,s^{-1}})\\,.\r\n\\end{equation*}\r\nHowever, for three of four remaining galaxies only the total mass of molecular hydrogen $M_\\mathrm{H_2}$ was found. Regan et al. (2001) make a conclusion based on the BIMA survey data that $\\Sigma _\\mathrm{H_2}(R)$ profile decreases exponentially with a scale equal to the scale length of the disc h on the average. Therefore for these remaining galaxies we found central surface densities from the formula of the total mass of the molecular disc $\\displaystyle \\Sigma _\\mathrm{H_2}(0) = \\frac{M_\\mathrm{H_2}}{2 {\\pi} \\, h^2}$ and then extended them exponentially with the appropriate h scale length. If more than one photometry is used for an examined galaxy this approach gives several possible profiles of $\\Sigma _\\mathrm{H_2}(R)$ and several estimates of Q, respectively both for one-fluid and two-component cases. We approximate the $\\Sigma _\\mathrm{H_2}(R)$ and $\\Sigma _\\mathrm{H\\, \\small {I}}(R)$ profiles using linear interpolation between points. The total gas surface density was corrected for the presence of helium and other heavy elements using $\\Sigma _\\mathrm{g} = 1.36\\,(\\Sigma _\\mathrm{H\\,\\small {I}} + \\Sigma _\\mathrm{H_2})$ formula (see for example Leroy et al. 2008).","Citation Text":["Yim & van der Hulst (2016)"],"Citation Start End":[[447,473]]} {"Identifier":"2018MNRAS.475.4891M__Hulst_2016_Instance_3","Paragraph":"For all galaxies the extended profiles of $\\Sigma _\\mathrm{H\\,\\small {I}}$ obtained from observations at the WSRT telescope were found in Yim & van der Hulst (2016) and Noordermeer et al. (2005). The surface density of $\\Sigma _\\mathrm{H_2}$ is usually calculated from observations of CO molecule lines, but the exact value of the conversion factor XCO remains debatable. If CO intensity profile is available, we follow the procedure described in Yim & van der Hulst (2016) to obtain $\\Sigma _\\mathrm{H_2}$. For NGC 4258, NGC 4725 (Yim & van der Hulst 2016), and NGC 2985 (Young et al. 1995), the CO(J = 1 → 0) line was used to calculate $\\Sigma _\\mathrm{H_2}$:\n\r\n\\begin{equation*}\r\n\\Sigma _\\mathrm{H_2} (\\text{M}_{\\odot }\\,\\mathrm{pc}^{-2}) = 3.2\\times I_\\mathrm{CO}(\\mathrm{K\\,km\\,s^{-1}})\\,.\r\n\\end{equation*}\r\nHowever, for three of four remaining galaxies only the total mass of molecular hydrogen $M_\\mathrm{H_2}$ was found. Regan et al. (2001) make a conclusion based on the BIMA survey data that $\\Sigma _\\mathrm{H_2}(R)$ profile decreases exponentially with a scale equal to the scale length of the disc h on the average. Therefore for these remaining galaxies we found central surface densities from the formula of the total mass of the molecular disc $\\displaystyle \\Sigma _\\mathrm{H_2}(0) = \\frac{M_\\mathrm{H_2}}{2 {\\pi} \\, h^2}$ and then extended them exponentially with the appropriate h scale length. If more than one photometry is used for an examined galaxy this approach gives several possible profiles of $\\Sigma _\\mathrm{H_2}(R)$ and several estimates of Q, respectively both for one-fluid and two-component cases. We approximate the $\\Sigma _\\mathrm{H_2}(R)$ and $\\Sigma _\\mathrm{H\\, \\small {I}}(R)$ profiles using linear interpolation between points. The total gas surface density was corrected for the presence of helium and other heavy elements using $\\Sigma _\\mathrm{g} = 1.36\\,(\\Sigma _\\mathrm{H\\,\\small {I}} + \\Sigma _\\mathrm{H_2})$ formula (see for example Leroy et al. 2008).","Citation Text":["Yim & van der Hulst 2016"],"Citation Start End":[[532,556]]} {"Identifier":"2015ApJ...814....4L__Heckman_et_al._2000_Instance_1","Paragraph":"We have also plotted the scaling relation of S and \n\n\n\n\n\n as suggested by the Schmidt SF relation \n\n\n\n\n\n (green dashed line). The relation is normalized such that the line passes through the MW average \n\n\n\n\n\n For data points that lie around this relation, \n\n\n\n\n\n is smaller for higher densities. For \n\n\n\n\n\n the ISM around the Schmidt relation has a fV,hot of only a few percent. Surprisingly, for ISM in star-burst regimes, little hot gas exists and the medium is thermally stable. Observationally, however, powerful winds are ubiquitously associated with such high SF rates, and the mass loading (\n\n\n\n\n\n) is on the order of unity or even higher (e.g., Heckman et al. 2000; Steidel et al. 2004). Note that we have found the PEH rate to be a very important factor in determining the thermal state of the ISM. If the PEH rates we have adopted are reasonable, then the data seem to suggest that one needs other mechanism(s) to drive a wind for the high density regions. For example, “clustering” of SNe may work, although a factor of 10 or more increase in S is needed for \n\n\n\n\n\n above the average value to have a thermally driven wind. Another factor is the pre-SN feedback, such as photo-ionization, radiation pressure and winds from massive stars, which can create low density tunnels, facilitating SN energy to leak out (e.g., Rogers & Pittard 2013). Alternatively, runaway OB stars, which can easily migrate more than a hundred parsecs, may lead to a significant fraction of core collapse SNe exploding outside the immediate high density SF clouds. For a low density medium \n\n\n\n\n\n the critical SN rate for the ISM to have a thermal runaway is much less stringent. Another possible mechanism for wind launching is by the cosmic rays. As the cosmic rays diffuse out, the pressure gradient exerts accelerating force on the baryonic gas. Recent simulations have shown that this mechanism is promising to drive winds with a reasonable mass loading (Uhlig et al. 2012; Hanasz et al. 2013; Salem & Bryan 2014).","Citation Text":["Heckman et al. 2000"],"Citation Start End":[[653,672]]} {"Identifier":"2018ApJ...865...60V__Chandler_&_Baym_1986_Instance_1","Paragraph":"The momentum equations for the neutron and proton–electron fluids in the MHD approximation are (Mendell 1991a, 1991b; Glampedakis et al. 2011)\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the smooth-averaged velocity of the proton–electron fluid, ρn,p are the mass densities of the fluids, pn,p are scalar potentials related to thermodynamic variables in Equation (146), and \n\n\n\n\n\n is the external driving force associated with the magnetic dipole torque on the star. The neutron fluid is inviscid, while the proton–electron fluid has kinematic viscosity νee arising from electron–electron scattering. The two fluids are coupled by the mutual friction force \n\n\n\n\n\n, which arises from electron scattering from magnetized neutron vortices and pinning interactions. The force acts equally and oppositely on the two fluids and is given by (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Barenghi et al. 1983; Chandler & Baym 1986; Mendell 1991b; Peralta 2007; Glampedakis et al. 2011)\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n are the mutual friction coefficients; the first term is dissipative and the second term is nondissipative. The mutual friction coefficients are related to scattering and pinning parameters in Section 3. Electron scattering from flux tubes is connected with the evolution of the magnetic field and describes processes analogous to ohmic and Hall diffusion; see, for example, Graber et al. (2015). These effects are small compared with the inertial modes studied in this paper; see Appendix B for further discussion. The restoring force due to tension of the vortex lines is (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Baym & Chandler 1983; Mendell 1991a; Peralta 2007; Glampedakis et al. 2011)\n8\n\n\n\n\n\nwhere νn is the vortex line tension parameter, defined in (124). The vortex line tension is negligible compared with other terms in (5) and (6); see Equation (168). We set the vortex tension to zero everywhere in this paper except in the analysis of the Donnelly–Glaberson instability in Section 4.2.1, where it determines the instability condition. In a type II superconductor, the magnetic stresses arise from the tension of the array of the quantized flux tubes and is given by (Easson & Pethick 1977)\n9\n\n\n\n\n\nwhere \n\n\n\n\n\n is the lower critical field for type II superconductivity. The evolution of the magnetic field is determined by the induction equation\n10\n\n\n\n\n\n\n","Citation Text":["Chandler & Baym 1986"],"Citation Start End":[[907,927]]} {"Identifier":"2018ApJ...865...60VGlampedakis_et_al._2011_Instance_1","Paragraph":"The momentum equations for the neutron and proton–electron fluids in the MHD approximation are (Mendell 1991a, 1991b; Glampedakis et al. 2011)\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the smooth-averaged velocity of the proton–electron fluid, ρn,p are the mass densities of the fluids, pn,p are scalar potentials related to thermodynamic variables in Equation (146), and \n\n\n\n\n\n is the external driving force associated with the magnetic dipole torque on the star. The neutron fluid is inviscid, while the proton–electron fluid has kinematic viscosity νee arising from electron–electron scattering. The two fluids are coupled by the mutual friction force \n\n\n\n\n\n, which arises from electron scattering from magnetized neutron vortices and pinning interactions. The force acts equally and oppositely on the two fluids and is given by (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Barenghi et al. 1983; Chandler & Baym 1986; Mendell 1991b; Peralta 2007; Glampedakis et al. 2011)\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n are the mutual friction coefficients; the first term is dissipative and the second term is nondissipative. The mutual friction coefficients are related to scattering and pinning parameters in Section 3. Electron scattering from flux tubes is connected with the evolution of the magnetic field and describes processes analogous to ohmic and Hall diffusion; see, for example, Graber et al. (2015). These effects are small compared with the inertial modes studied in this paper; see Appendix B for further discussion. The restoring force due to tension of the vortex lines is (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Baym & Chandler 1983; Mendell 1991a; Peralta 2007; Glampedakis et al. 2011)\n8\n\n\n\n\n\nwhere νn is the vortex line tension parameter, defined in (124). The vortex line tension is negligible compared with other terms in (5) and (6); see Equation (168). We set the vortex tension to zero everywhere in this paper except in the analysis of the Donnelly–Glaberson instability in Section 4.2.1, where it determines the instability condition. In a type II superconductor, the magnetic stresses arise from the tension of the array of the quantized flux tubes and is given by (Easson & Pethick 1977)\n9\n\n\n\n\n\nwhere \n\n\n\n\n\n is the lower critical field for type II superconductivity. The evolution of the magnetic field is determined by the induction equation\n10\n\n\n\n\n\n\n","Citation Text":["Glampedakis et al. 2011"],"Citation Start End":[[118,141]]} {"Identifier":"2018ApJ...865...60VBaym_&_Chandler_1983_Instance_1","Paragraph":"The momentum equations for the neutron and proton–electron fluids in the MHD approximation are (Mendell 1991a, 1991b; Glampedakis et al. 2011)\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the smooth-averaged velocity of the proton–electron fluid, ρn,p are the mass densities of the fluids, pn,p are scalar potentials related to thermodynamic variables in Equation (146), and \n\n\n\n\n\n is the external driving force associated with the magnetic dipole torque on the star. The neutron fluid is inviscid, while the proton–electron fluid has kinematic viscosity νee arising from electron–electron scattering. The two fluids are coupled by the mutual friction force \n\n\n\n\n\n, which arises from electron scattering from magnetized neutron vortices and pinning interactions. The force acts equally and oppositely on the two fluids and is given by (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Barenghi et al. 1983; Chandler & Baym 1986; Mendell 1991b; Peralta 2007; Glampedakis et al. 2011)\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n are the mutual friction coefficients; the first term is dissipative and the second term is nondissipative. The mutual friction coefficients are related to scattering and pinning parameters in Section 3. Electron scattering from flux tubes is connected with the evolution of the magnetic field and describes processes analogous to ohmic and Hall diffusion; see, for example, Graber et al. (2015). These effects are small compared with the inertial modes studied in this paper; see Appendix B for further discussion. The restoring force due to tension of the vortex lines is (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Baym & Chandler 1983; Mendell 1991a; Peralta 2007; Glampedakis et al. 2011)\n8\n\n\n\n\n\nwhere νn is the vortex line tension parameter, defined in (124). The vortex line tension is negligible compared with other terms in (5) and (6); see Equation (168). We set the vortex tension to zero everywhere in this paper except in the analysis of the Donnelly–Glaberson instability in Section 4.2.1, where it determines the instability condition. In a type II superconductor, the magnetic stresses arise from the tension of the array of the quantized flux tubes and is given by (Easson & Pethick 1977)\n9\n\n\n\n\n\nwhere \n\n\n\n\n\n is the lower critical field for type II superconductivity. The evolution of the magnetic field is determined by the induction equation\n10\n\n\n\n\n\n\n","Citation Text":["Baym & Chandler 1983"],"Citation Start End":[[1650,1670]]} {"Identifier":"2018ApJ...865...60VEasson_&_Pethick_1977_Instance_1","Paragraph":"The momentum equations for the neutron and proton–electron fluids in the MHD approximation are (Mendell 1991a, 1991b; Glampedakis et al. 2011)\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\nwhere \n\n\n\n\n\n is the smooth-averaged velocity of the proton–electron fluid, ρn,p are the mass densities of the fluids, pn,p are scalar potentials related to thermodynamic variables in Equation (146), and \n\n\n\n\n\n is the external driving force associated with the magnetic dipole torque on the star. The neutron fluid is inviscid, while the proton–electron fluid has kinematic viscosity νee arising from electron–electron scattering. The two fluids are coupled by the mutual friction force \n\n\n\n\n\n, which arises from electron scattering from magnetized neutron vortices and pinning interactions. The force acts equally and oppositely on the two fluids and is given by (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Barenghi et al. 1983; Chandler & Baym 1986; Mendell 1991b; Peralta 2007; Glampedakis et al. 2011)\n7\n\n\n\n\n\nwhere \n\n\n\n\n\n and \n\n\n\n\n\n are the mutual friction coefficients; the first term is dissipative and the second term is nondissipative. The mutual friction coefficients are related to scattering and pinning parameters in Section 3. Electron scattering from flux tubes is connected with the evolution of the magnetic field and describes processes analogous to ohmic and Hall diffusion; see, for example, Graber et al. (2015). These effects are small compared with the inertial modes studied in this paper; see Appendix B for further discussion. The restoring force due to tension of the vortex lines is (see, e.g., Hall 1960; Khalatnikov 1965; Hills & Roberts 1977; Baym & Chandler 1983; Mendell 1991a; Peralta 2007; Glampedakis et al. 2011)\n8\n\n\n\n\n\nwhere νn is the vortex line tension parameter, defined in (124). The vortex line tension is negligible compared with other terms in (5) and (6); see Equation (168). We set the vortex tension to zero everywhere in this paper except in the analysis of the Donnelly–Glaberson instability in Section 4.2.1, where it determines the instability condition. In a type II superconductor, the magnetic stresses arise from the tension of the array of the quantized flux tubes and is given by (Easson & Pethick 1977)\n9\n\n\n\n\n\nwhere \n\n\n\n\n\n is the lower critical field for type II superconductivity. The evolution of the magnetic field is determined by the induction equation\n10\n\n\n\n\n\n\n","Citation Text":["Easson & Pethick 1977"],"Citation Start End":[[2215,2236]]} {"Identifier":"2021MNRAS.507.2766S__Chanmugan_1977_Instance_1","Paragraph":"As seen in the previous section, the mass of the PNS increases with the accretion, which eventually approaches the maximum mass allowed with the adopted EOSs. Then, the PNS would gravitationally collapse to a black hole. The moment when the PNS approaches its maximum mass corresponds to the onset of the instability. In order to determine the onset of instability in the evolution of the PNSs, we make a linear analysis with the radial perturbation on the PNS models at each time-step after corebounce. For this purpose, one can derive the perturbation equations as\n(3)$$\\begin{eqnarray*}\r\n\\frac{\\mathrm{ d}\\xi }{\\mathrm{ d}r} &=& -\\left[\\frac{3}{r} + \\frac{p^{\\prime }}{p+\\varepsilon }\\right]\\xi - \\frac{\\eta }{r\\Gamma },\r\n\\end{eqnarray*}$$(4)$$\\begin{eqnarray*}\r\n\\frac{\\mathrm{ d}\\eta }{\\mathrm{ d}r} &=& \\left[r(p+\\varepsilon) e^{2\\Lambda }\\left(\\frac{\\omega ^2}{p} e^{-2\\Phi } - 8\\pi \\right) - \\frac{4p^{\\prime }}{p} + \\frac{r(p^{\\prime })^2}{p(p+\\varepsilon)}\\right]\\xi \\nonumber\\\\\r\n&&-\\, \\left[\\frac{\\varepsilon p^{\\prime }}{p(p+\\varepsilon)} + 4\\pi r(p+\\varepsilon)e^{2\\Lambda }\\right]\\eta ,\r\n\\end{eqnarray*}$$where p, ε, and Γ denote the pressure, energy density, and adiabatic index for the background PNS models, while ξ and η are perturbative variables given by ξ ≡ Δr\/r and η ≡ Δp\/p with the radial displacement, Δr, and the Lagrangian perturbation of pressure, Δp (Chandrasekhar 1964; Chanmugan 1977; Gondek, Haensel & Zdunik 1997).3 The prime in the equations denotes the radial derivative and the adiabatic index is given by\n(5)$$\\begin{eqnarray*}\r\n\\Gamma \\equiv \\left(\\frac{\\partial \\ln p}{\\partial \\ln n_{\\rm b}}\\right)_s = \\frac{p+\\varepsilon }{p}c_\\mathrm{ s}^2,\r\n\\end{eqnarray*}$$where nb, s, and cs denote the baryon number density, entropy per baryon, and sound velocity, respectively. We remark that one can derive the Sturm–Liouville type second-order differential equation with respect to ξ from equations (3) and (4). To solve the eigenvalue problem with respect to the eigenvalue ω2, one should impose the appropriate boundary conditions. The boundary condition at the stellar surface comes from the condition to remove the singularity in equation (4) (Chanmugan 1977), i.e.\n(6)$$\\begin{eqnarray*}\r\n\\eta = -\\left[\\left(\\frac{\\omega ^2R_{\\rm PNS}^3}{M_{\\rm PNS}} + \\frac{M_{\\rm PNS}}{R_{\\rm PNS}}\\right) \\left(1-\\frac{2M_{\\rm PNS}}{R_{\\rm PNS}}\\right)^{-1}+ 4\\right]\\xi ,\r\n\\end{eqnarray*}$$while the boundary condition at the centre is the regularity condition, i.e.\n(7)$$\\begin{eqnarray*}\r\n3\\Gamma \\xi + \\eta = 0.\r\n\\end{eqnarray*}$$In addition, as normalization of the eigenfunction, we set ξ = 1 at the stellar centre. Then, with the resultant eigenvalue ω2, the frequency of radial oscillations are given by\n(8)$$\\begin{eqnarray*}\r\nf_{\\xi } = {\\rm sgn}(\\omega ^2)\\sqrt{|\\omega ^2|}\/2\\pi ,\r\n\\end{eqnarray*}$$where the system is unstable when ω2 becomes negative.","Citation Text":["Chanmugan 1977"],"Citation Start End":[[1423,1437]]} {"Identifier":"2021MNRAS.507.2766S__Chanmugan_1977_Instance_2","Paragraph":"As seen in the previous section, the mass of the PNS increases with the accretion, which eventually approaches the maximum mass allowed with the adopted EOSs. Then, the PNS would gravitationally collapse to a black hole. The moment when the PNS approaches its maximum mass corresponds to the onset of the instability. In order to determine the onset of instability in the evolution of the PNSs, we make a linear analysis with the radial perturbation on the PNS models at each time-step after corebounce. For this purpose, one can derive the perturbation equations as\n(3)$$\\begin{eqnarray*}\r\n\\frac{\\mathrm{ d}\\xi }{\\mathrm{ d}r} &=& -\\left[\\frac{3}{r} + \\frac{p^{\\prime }}{p+\\varepsilon }\\right]\\xi - \\frac{\\eta }{r\\Gamma },\r\n\\end{eqnarray*}$$(4)$$\\begin{eqnarray*}\r\n\\frac{\\mathrm{ d}\\eta }{\\mathrm{ d}r} &=& \\left[r(p+\\varepsilon) e^{2\\Lambda }\\left(\\frac{\\omega ^2}{p} e^{-2\\Phi } - 8\\pi \\right) - \\frac{4p^{\\prime }}{p} + \\frac{r(p^{\\prime })^2}{p(p+\\varepsilon)}\\right]\\xi \\nonumber\\\\\r\n&&-\\, \\left[\\frac{\\varepsilon p^{\\prime }}{p(p+\\varepsilon)} + 4\\pi r(p+\\varepsilon)e^{2\\Lambda }\\right]\\eta ,\r\n\\end{eqnarray*}$$where p, ε, and Γ denote the pressure, energy density, and adiabatic index for the background PNS models, while ξ and η are perturbative variables given by ξ ≡ Δr\/r and η ≡ Δp\/p with the radial displacement, Δr, and the Lagrangian perturbation of pressure, Δp (Chandrasekhar 1964; Chanmugan 1977; Gondek, Haensel & Zdunik 1997).3 The prime in the equations denotes the radial derivative and the adiabatic index is given by\n(5)$$\\begin{eqnarray*}\r\n\\Gamma \\equiv \\left(\\frac{\\partial \\ln p}{\\partial \\ln n_{\\rm b}}\\right)_s = \\frac{p+\\varepsilon }{p}c_\\mathrm{ s}^2,\r\n\\end{eqnarray*}$$where nb, s, and cs denote the baryon number density, entropy per baryon, and sound velocity, respectively. We remark that one can derive the Sturm–Liouville type second-order differential equation with respect to ξ from equations (3) and (4). To solve the eigenvalue problem with respect to the eigenvalue ω2, one should impose the appropriate boundary conditions. The boundary condition at the stellar surface comes from the condition to remove the singularity in equation (4) (Chanmugan 1977), i.e.\n(6)$$\\begin{eqnarray*}\r\n\\eta = -\\left[\\left(\\frac{\\omega ^2R_{\\rm PNS}^3}{M_{\\rm PNS}} + \\frac{M_{\\rm PNS}}{R_{\\rm PNS}}\\right) \\left(1-\\frac{2M_{\\rm PNS}}{R_{\\rm PNS}}\\right)^{-1}+ 4\\right]\\xi ,\r\n\\end{eqnarray*}$$while the boundary condition at the centre is the regularity condition, i.e.\n(7)$$\\begin{eqnarray*}\r\n3\\Gamma \\xi + \\eta = 0.\r\n\\end{eqnarray*}$$In addition, as normalization of the eigenfunction, we set ξ = 1 at the stellar centre. Then, with the resultant eigenvalue ω2, the frequency of radial oscillations are given by\n(8)$$\\begin{eqnarray*}\r\nf_{\\xi } = {\\rm sgn}(\\omega ^2)\\sqrt{|\\omega ^2|}\/2\\pi ,\r\n\\end{eqnarray*}$$where the system is unstable when ω2 becomes negative.","Citation Text":["Chanmugan 1977"],"Citation Start End":[[2205,2219]]} {"Identifier":"2018ApJ...860..121F__Nishikawa_et_al._2016_Instance_1","Paragraph":"To calculate the synchrotron emission from the previous RMHD jet models, we need to establish some assumptions. While the radio continuum emission we are interested in is being produced by a population of non-thermal electrons (and maybe positrons), the RMHD simulations discussed previously account only for the evolution of the thermal electrons present in the jet. Establishing a relationship between the thermal and non-thermal populations requires a detailed prescription for the particle acceleration processes that connect both populations, presumably taking place in strong shocks or in magnetic reconnection events (see e.g., Sironi et al. 2015). A proper treatment of particle acceleration\/injection in shocks (e.g., Kirk et al. 2000) or magnetic reconnection (e.g., Lyubarsky 2005) requires a microscopic description of the fluid, such as in particle-in-cell (PIC) simulations (e.g., Nishikawa et al. 2016), and its implementation in macroscopic RMHD models, such as the one used here, still falls outside current computing capabilities, given the vastly different scales involved. Nevertheless, as a first-order approximation, we consider that the internal energy of the non-thermal population is a constant fraction of the thermal electrons considered in the RMHD simulations (e.g., Gómez et al. 1995, 1997; Komissarov & Falle 1997; Broderick & McKinney 2010; Porth et al. 2011). Alternatively, the non-thermal population can also be considered to be proportional to the magnetic energy density (e.g., Porth et al. 2011), which determines the particle acceleration efficiency in shocks and magnetic reconnection events. No significant differences are found in our emission calculations when considering the latter approach for particle acceleration, given the similarities between the gas pressure and magnetic energy density distributions in our RMHD simulations, except for the particular case of jet spine brightening discussed in more detail in Section 3.3. On the other hand, we note that particle acceleration at shock fronts is probably the most important ingredient for computing the expected non-thermal emission from our RMHD simulations. Our results should therefore be considered in these cases as a first-order approximation, which could be used as a base model to test different prescriptions for in situ particle acceleration in future modeling.","Citation Text":["Nishikawa et al. 2016"],"Citation Start End":[[895,916]]} {"Identifier":"2018ApJ...860..121FSironi_et_al._2015_Instance_1","Paragraph":"To calculate the synchrotron emission from the previous RMHD jet models, we need to establish some assumptions. While the radio continuum emission we are interested in is being produced by a population of non-thermal electrons (and maybe positrons), the RMHD simulations discussed previously account only for the evolution of the thermal electrons present in the jet. Establishing a relationship between the thermal and non-thermal populations requires a detailed prescription for the particle acceleration processes that connect both populations, presumably taking place in strong shocks or in magnetic reconnection events (see e.g., Sironi et al. 2015). A proper treatment of particle acceleration\/injection in shocks (e.g., Kirk et al. 2000) or magnetic reconnection (e.g., Lyubarsky 2005) requires a microscopic description of the fluid, such as in particle-in-cell (PIC) simulations (e.g., Nishikawa et al. 2016), and its implementation in macroscopic RMHD models, such as the one used here, still falls outside current computing capabilities, given the vastly different scales involved. Nevertheless, as a first-order approximation, we consider that the internal energy of the non-thermal population is a constant fraction of the thermal electrons considered in the RMHD simulations (e.g., Gómez et al. 1995, 1997; Komissarov & Falle 1997; Broderick & McKinney 2010; Porth et al. 2011). Alternatively, the non-thermal population can also be considered to be proportional to the magnetic energy density (e.g., Porth et al. 2011), which determines the particle acceleration efficiency in shocks and magnetic reconnection events. No significant differences are found in our emission calculations when considering the latter approach for particle acceleration, given the similarities between the gas pressure and magnetic energy density distributions in our RMHD simulations, except for the particular case of jet spine brightening discussed in more detail in Section 3.3. On the other hand, we note that particle acceleration at shock fronts is probably the most important ingredient for computing the expected non-thermal emission from our RMHD simulations. Our results should therefore be considered in these cases as a first-order approximation, which could be used as a base model to test different prescriptions for in situ particle acceleration in future modeling.","Citation Text":["Sironi et al. 2015"],"Citation Start End":[[635,653]]} {"Identifier":"2018ApJ...860..121FBroderick_&_McKinney_2010_Instance_1","Paragraph":"To calculate the synchrotron emission from the previous RMHD jet models, we need to establish some assumptions. While the radio continuum emission we are interested in is being produced by a population of non-thermal electrons (and maybe positrons), the RMHD simulations discussed previously account only for the evolution of the thermal electrons present in the jet. Establishing a relationship between the thermal and non-thermal populations requires a detailed prescription for the particle acceleration processes that connect both populations, presumably taking place in strong shocks or in magnetic reconnection events (see e.g., Sironi et al. 2015). A proper treatment of particle acceleration\/injection in shocks (e.g., Kirk et al. 2000) or magnetic reconnection (e.g., Lyubarsky 2005) requires a microscopic description of the fluid, such as in particle-in-cell (PIC) simulations (e.g., Nishikawa et al. 2016), and its implementation in macroscopic RMHD models, such as the one used here, still falls outside current computing capabilities, given the vastly different scales involved. Nevertheless, as a first-order approximation, we consider that the internal energy of the non-thermal population is a constant fraction of the thermal electrons considered in the RMHD simulations (e.g., Gómez et al. 1995, 1997; Komissarov & Falle 1997; Broderick & McKinney 2010; Porth et al. 2011). Alternatively, the non-thermal population can also be considered to be proportional to the magnetic energy density (e.g., Porth et al. 2011), which determines the particle acceleration efficiency in shocks and magnetic reconnection events. No significant differences are found in our emission calculations when considering the latter approach for particle acceleration, given the similarities between the gas pressure and magnetic energy density distributions in our RMHD simulations, except for the particular case of jet spine brightening discussed in more detail in Section 3.3. On the other hand, we note that particle acceleration at shock fronts is probably the most important ingredient for computing the expected non-thermal emission from our RMHD simulations. Our results should therefore be considered in these cases as a first-order approximation, which could be used as a base model to test different prescriptions for in situ particle acceleration in future modeling.","Citation Text":["Broderick & McKinney 2010"],"Citation Start End":[[1346,1371]]} {"Identifier":"2016AandA...585A..48G__Finkelstein_et_al._2015_Instance_1","Paragraph":"The relative escape fraction of galaxies brighter than M1500 ~ −20.2 (L = 0.5L∗) should be ~16% to provide a photoionization rate Γ-12 ~ 0.95, in agreement with the observed value at z ~ 3, shown in Fig. 7. Alternatively, the escape fraction can remain at approximately a few percent, but the LF must be integrated down to very faint magnitudes, at M1500 = −14.2 (Fontanot et al. 2014; Alavi et al. 2014) to yield Γ-12 ~ 0.9. The calculations above are quite conservative, since we are assuming a rather steep LF (α = −1.73). At z ~ 3 the estimated slopes of the galaxy LF are generally flatter, with α ~ [−1.4,−1.5] (Sawiki & Thompson 2006; Finkelstein et al. 2015; Parsa et al. 2015), with the exception of the LF of LAEs by Cassata et al. (2011), which has α ~ −1.8 at z ≥ 3. Adopting the parametrization of Sawiki & Thompson (2006), with α = −1.43, and integrating down to M1500 = −14.2, the ionizing emissivity is Γ-12 ≤ 0.31, which is insufficient to keep the Universe reionized. Similarly, if we adopt the LF by Cucciati et al. (2012) with a slightly steeper slope (α = −1.50), but brighter M∗, we find an emissivity of Γ-12 ≤ 0.26 at M1500 = −14.2, far from providing enough ionizing photons to maintain the reionization of the Universe. The latter LF is based on the VVDS (Le Fèvre et al. 2013) spectroscopic survey, so it should be robust against interlopers in the z ~ 3 LF. At z ≥ 3, Cassata et al. (2011) find that the LF of LAEs is relatively steep, with a slope of ~− 1.8. However, these galaxies are much fainter than the typical UV selected galaxies discovered at the same redshifts. They measured a star formation rate density, which is a factor of 5 lower than that by Reddy & Steidel (2009), with the implication of a lesser contribution of the LAEs to the HI ionizing background at z ~ 3. Table 3 summarizes the different HI photoionization rates derived for different parametrization of the z ~ 3 galaxy LF and at different luminosities. ","Citation Text":["Finkelstein et al. 2015"],"Citation Start End":[[643,666]]} {"Identifier":"2015MNRAS.453.1577R__West,_Jones_&_Forman_1995_Instance_1","Paragraph":"There is not yet a clear consensus for observational efforts to detect primordial galaxy alignments in clusters or superclusters. Rood & Sastry (1972) were the first to claim that satellite galaxies in Abell 2199 tend to point in the direction of the major axis of the BCG. Subsequently, primordial galaxy alignment was found in more clusters, such as Abell 521 (Plionis et al. 2003), Abell 1689 (Hung et al. 2010), Coma (Djorgovski 1983; Kitzbichler & Saurer 2003), Virgo (West & Blakeslee 2000), Abell 999 and Abell 2197 (Adams, Storm & Strom 1980; Thompson 1976), and in some cluster samples [Yang et al. 2006 (0.01 z 0.2); Plionis 1994; Plionis et al. 2003 (z 0.15); West, Jones & Forman 1995 (z 0.2); Agustsson & Brainerd 2006 (median redshift z = 0.058); Faltenbacher et al. 2007 (0.01 z 0.2)]. However, some other measurements have been consistent with random orientations of satellite galaxies in clusters [e.g. Hawley & Peebles 1975; Dekel 1985; van Kampen & Rhee 1990; Godłowski & Ostrowski 1999; Strazzullo et al. 2005 (z 0.27); Torlina, De Propris & West 2007; Trevese, Cirimele & Flin 1992; Panko, Juszczyk & Flin 2009 (z 0.18); Sifón et al. 2015 (0.05 z 0.55)]. On one hand, the primordial alignment is primarily found in unrelaxed clusters, such as Coma (Sanders et al. 2013; Simionescu et al. 2013), Abell 1689 (Kawaharada et al. 2010), Virgo (Urban et al. 2011) and Abell 521 (Maurogordato et al. 2000; Ferrari et al. 2003, 2006), which agrees with stronger alignment in dynamically young clusters. On the other hand, at higher redshifts, the primordial alignment is denied in many clusters (Sifón et al. 2015) other than Abell 521 (z ∼ 0.25). This is unexpected because the fraction of the dynamically young clusters at high redshifts is larger (Hashimoto et al. 2007; Maughan, Forman & Van Speybroeck 2008; Mann & Ebeling 2012; Weißmann, Böhringer & Chon 2013), according to the hierarchical clustering models of structure formation.","Citation Text":["West, Jones & Forman 1995"],"Citation Start End":[[674,699]]} {"Identifier":"2016ApJ...831..194W__Fürst_et_al._2013_Instance_1","Paragraph":"We performed our spectral fit in the XSPEC v12.8.2 and 12.9.0 (Arnaud 1996) spectral analysis environments. We verified that the resulting fits are consistent across both versions of XSPEC. Twenty-three parameters describe the spectral continuum and emission lines that NuSTAR observes in the 4–79 keV range. Six parameters describe two iron emission lines (we use the Gaussian function for both lines), three describe the cyclotron resonant scattering absorption feature (CRSF), one parameter describes the interstellar absorption (\n\n\n\n\n\n), and one parameter describes the cross-normalization of the FPMA and FPMB modules (\n\n\n\n\n\n). The absorbing column is frozen at \n\n\n\n\n\n cm−2, a value that approximates the galactic absorption to Her X-1 (Fürst et al. 2013). We utilized the tbabs absorption model with the “WILM” abundance table and the “BCMC” cross-sections (Wilms et al. 2000). This leaves 12 parameters to describe the RDRS model. One of these is an RDRS model normalization that we freeze at 1.0. One is a numerical switch that allows us to turn on or off any of the three principal seed-photon processes for the Comptonization (see Section 2). We freeze the distance to the Her X-1 system at D = 6.6 kpc (Reynolds et al. 1997), and the NS mass and radius are set to their standard values (\n\n\n\n\n\n and 10 km). The distance to Her X-1 obtained by Reynolds et al. of \n\n\n\n\n\n kpc is sufficiently consistent, for our purposes, with a more recently determined distance of \n\n\n\n\n\n kpc obtained by Leahy & Abdallah (2014). Thus, we adopt the Reynolds et al. distance for these calculations. The value of the input magnetic field strength to the RDRS model is tied to the centroid of the fitted cyclotron absorption line (\n\n\n\n\n\n) via \n\n\n\n\n\n where z* is the gravitational redshift to the NS surface. The six remaining parameters describing the RDRS model (BW) are: mass accretion rate (\n\n\n\n\n\n), plasma Comptonizing temperature (Te), accretion cap radius (r0), scattering cross-section perpendicular to the magnetic field (\n\n\n\n\n\n), scattering cross-section parallel to the magnetic field (\n\n\n\n\n\n), and average scattering cross-section (\n\n\n\n\n\n). The scattering cross-section perpendicular to the magnetic field (\n\n\n\n\n\n) is frozen at the Thomson electron scattering cross-section (\n\n\n\n\n\n). This leaves five free parameters, \n\n\n\n\n\n, Te, r0, \n\n\n\n\n\n, and \n\n\n\n\n\n, to describe the X-ray continuum.","Citation Text":["Fürst et al. 2013"],"Citation Start End":[[743,760]]} {"Identifier":"2019ApJ...880..119C__Smith_et_al._2012_Instance_1","Paragraph":"The extent of the evolution of the faint red-sequence population, however, is still under debate. As opposed to local clusters that exhibit a flat faint end, or even an upturn at the faint end of their red-sequence LFs (e.g., Popesso et al. 2006; Agulli et al. 2014; Moretti et al. 2015; Lan et al. 2016), various studies have revealed that clusters at intermediate and high redshifts show a continual decrease in the fraction of the faint red-sequence population with redshift, which indicates a gradual buildup of the faint red-sequence population over time since z ∼ 1.5 (e.g., Dressler et al. 1997; Smail et al. 1998; De Lucia et al. 2004, 2007; Kodama et al. 2004; Tanaka et al. 2007; Gilbank et al. 2008; Rudnick et al. 2009, 2012; Stott et al. 2009; Martinet et al. 2015; Zenteno et al. 2016; Sarron et al. 2018; Zhang et al. 2019). This is also supported by findings that cluster galaxies on the high-mass end of the red sequence are on average older than those on the low-mass end (e.g., Nelan et al. 2005; Sánchez-Blázquez et al. 2009; Demarco et al. 2010a; Smith et al. 2012). Contrary to the above-mentioned studies, a number of studies have reported that there is little or no evolution of the faint end of the red-sequence cluster LF up to z ∼ 1.5 (e.g., Andreon 2006; Crawford et al. 2009; De Propris et al. 2013, 2015; Andreon et al. 2014; Cerulo et al. 2016), which in turn suggests the early formation of the faint end, similar to bright red-sequence galaxies. De Propris et al. (2013) proposed that the discrepancy is primarily caused by surface brightness selection effects, which lowers the detectability of faint galaxies at high redshift. Nevertheless, a recent study by Martinet et al. (2017) extensively investigated the effect of surface brightness dimming with 16 CLASH clusters in the redshift range of 0.2 z 0.6. They concluded that surface brightness dimming alone could not explain the observed redshift evolution of the faint end. Other possible explanations of the discrepancy invoke the radial and mass dependence of the faint red-sequence population, both of which are also debated in local cluster LF studies (see, e.g., Popesso et al. 2006; Barkhouse et al. 2007; Lan et al. 2016). While there may be a (weak) dependence of the red-sequence LF on cluster mass (or cluster properties that are mass proxies) at intermediate redshift (e.g., De Lucia et al. 2007; Muzzin et al. 2007; Rudnick et al. 2009; Martinet et al. 2015), it remains unclear whether this effect exists at higher redshift. It is also possible that the disagreements in the literature are driven by the large cluster-to-cluster variations, sample selections, or methods used to derive the LF, as observed in most of the above-mentioned works.","Citation Text":["Smith et al. 2012"],"Citation Start End":[[1068,1085]]} {"Identifier":"2019ApJ...880..119CPopesso_et_al._2006_Instance_1","Paragraph":"The extent of the evolution of the faint red-sequence population, however, is still under debate. As opposed to local clusters that exhibit a flat faint end, or even an upturn at the faint end of their red-sequence LFs (e.g., Popesso et al. 2006; Agulli et al. 2014; Moretti et al. 2015; Lan et al. 2016), various studies have revealed that clusters at intermediate and high redshifts show a continual decrease in the fraction of the faint red-sequence population with redshift, which indicates a gradual buildup of the faint red-sequence population over time since z ∼ 1.5 (e.g., Dressler et al. 1997; Smail et al. 1998; De Lucia et al. 2004, 2007; Kodama et al. 2004; Tanaka et al. 2007; Gilbank et al. 2008; Rudnick et al. 2009, 2012; Stott et al. 2009; Martinet et al. 2015; Zenteno et al. 2016; Sarron et al. 2018; Zhang et al. 2019). This is also supported by findings that cluster galaxies on the high-mass end of the red sequence are on average older than those on the low-mass end (e.g., Nelan et al. 2005; Sánchez-Blázquez et al. 2009; Demarco et al. 2010a; Smith et al. 2012). Contrary to the above-mentioned studies, a number of studies have reported that there is little or no evolution of the faint end of the red-sequence cluster LF up to z ∼ 1.5 (e.g., Andreon 2006; Crawford et al. 2009; De Propris et al. 2013, 2015; Andreon et al. 2014; Cerulo et al. 2016), which in turn suggests the early formation of the faint end, similar to bright red-sequence galaxies. De Propris et al. (2013) proposed that the discrepancy is primarily caused by surface brightness selection effects, which lowers the detectability of faint galaxies at high redshift. Nevertheless, a recent study by Martinet et al. (2017) extensively investigated the effect of surface brightness dimming with 16 CLASH clusters in the redshift range of 0.2 z 0.6. They concluded that surface brightness dimming alone could not explain the observed redshift evolution of the faint end. Other possible explanations of the discrepancy invoke the radial and mass dependence of the faint red-sequence population, both of which are also debated in local cluster LF studies (see, e.g., Popesso et al. 2006; Barkhouse et al. 2007; Lan et al. 2016). While there may be a (weak) dependence of the red-sequence LF on cluster mass (or cluster properties that are mass proxies) at intermediate redshift (e.g., De Lucia et al. 2007; Muzzin et al. 2007; Rudnick et al. 2009; Martinet et al. 2015), it remains unclear whether this effect exists at higher redshift. It is also possible that the disagreements in the literature are driven by the large cluster-to-cluster variations, sample selections, or methods used to derive the LF, as observed in most of the above-mentioned works.","Citation Text":["Popesso et al. 2006"],"Citation Start End":[[226,245]]} {"Identifier":"2019ApJ...880..119CPopesso_et_al._2006_Instance_2","Paragraph":"The extent of the evolution of the faint red-sequence population, however, is still under debate. As opposed to local clusters that exhibit a flat faint end, or even an upturn at the faint end of their red-sequence LFs (e.g., Popesso et al. 2006; Agulli et al. 2014; Moretti et al. 2015; Lan et al. 2016), various studies have revealed that clusters at intermediate and high redshifts show a continual decrease in the fraction of the faint red-sequence population with redshift, which indicates a gradual buildup of the faint red-sequence population over time since z ∼ 1.5 (e.g., Dressler et al. 1997; Smail et al. 1998; De Lucia et al. 2004, 2007; Kodama et al. 2004; Tanaka et al. 2007; Gilbank et al. 2008; Rudnick et al. 2009, 2012; Stott et al. 2009; Martinet et al. 2015; Zenteno et al. 2016; Sarron et al. 2018; Zhang et al. 2019). This is also supported by findings that cluster galaxies on the high-mass end of the red sequence are on average older than those on the low-mass end (e.g., Nelan et al. 2005; Sánchez-Blázquez et al. 2009; Demarco et al. 2010a; Smith et al. 2012). Contrary to the above-mentioned studies, a number of studies have reported that there is little or no evolution of the faint end of the red-sequence cluster LF up to z ∼ 1.5 (e.g., Andreon 2006; Crawford et al. 2009; De Propris et al. 2013, 2015; Andreon et al. 2014; Cerulo et al. 2016), which in turn suggests the early formation of the faint end, similar to bright red-sequence galaxies. De Propris et al. (2013) proposed that the discrepancy is primarily caused by surface brightness selection effects, which lowers the detectability of faint galaxies at high redshift. Nevertheless, a recent study by Martinet et al. (2017) extensively investigated the effect of surface brightness dimming with 16 CLASH clusters in the redshift range of 0.2 z 0.6. They concluded that surface brightness dimming alone could not explain the observed redshift evolution of the faint end. Other possible explanations of the discrepancy invoke the radial and mass dependence of the faint red-sequence population, both of which are also debated in local cluster LF studies (see, e.g., Popesso et al. 2006; Barkhouse et al. 2007; Lan et al. 2016). While there may be a (weak) dependence of the red-sequence LF on cluster mass (or cluster properties that are mass proxies) at intermediate redshift (e.g., De Lucia et al. 2007; Muzzin et al. 2007; Rudnick et al. 2009; Martinet et al. 2015), it remains unclear whether this effect exists at higher redshift. It is also possible that the disagreements in the literature are driven by the large cluster-to-cluster variations, sample selections, or methods used to derive the LF, as observed in most of the above-mentioned works.","Citation Text":["Popesso et al. 2006"],"Citation Start End":[[2159,2178]]} {"Identifier":"2019ApJ...880..119CDe_Propris_et_al._2013_Instance_1","Paragraph":"The extent of the evolution of the faint red-sequence population, however, is still under debate. As opposed to local clusters that exhibit a flat faint end, or even an upturn at the faint end of their red-sequence LFs (e.g., Popesso et al. 2006; Agulli et al. 2014; Moretti et al. 2015; Lan et al. 2016), various studies have revealed that clusters at intermediate and high redshifts show a continual decrease in the fraction of the faint red-sequence population with redshift, which indicates a gradual buildup of the faint red-sequence population over time since z ∼ 1.5 (e.g., Dressler et al. 1997; Smail et al. 1998; De Lucia et al. 2004, 2007; Kodama et al. 2004; Tanaka et al. 2007; Gilbank et al. 2008; Rudnick et al. 2009, 2012; Stott et al. 2009; Martinet et al. 2015; Zenteno et al. 2016; Sarron et al. 2018; Zhang et al. 2019). This is also supported by findings that cluster galaxies on the high-mass end of the red sequence are on average older than those on the low-mass end (e.g., Nelan et al. 2005; Sánchez-Blázquez et al. 2009; Demarco et al. 2010a; Smith et al. 2012). Contrary to the above-mentioned studies, a number of studies have reported that there is little or no evolution of the faint end of the red-sequence cluster LF up to z ∼ 1.5 (e.g., Andreon 2006; Crawford et al. 2009; De Propris et al. 2013, 2015; Andreon et al. 2014; Cerulo et al. 2016), which in turn suggests the early formation of the faint end, similar to bright red-sequence galaxies. De Propris et al. (2013) proposed that the discrepancy is primarily caused by surface brightness selection effects, which lowers the detectability of faint galaxies at high redshift. Nevertheless, a recent study by Martinet et al. (2017) extensively investigated the effect of surface brightness dimming with 16 CLASH clusters in the redshift range of 0.2 z 0.6. They concluded that surface brightness dimming alone could not explain the observed redshift evolution of the faint end. Other possible explanations of the discrepancy invoke the radial and mass dependence of the faint red-sequence population, both of which are also debated in local cluster LF studies (see, e.g., Popesso et al. 2006; Barkhouse et al. 2007; Lan et al. 2016). While there may be a (weak) dependence of the red-sequence LF on cluster mass (or cluster properties that are mass proxies) at intermediate redshift (e.g., De Lucia et al. 2007; Muzzin et al. 2007; Rudnick et al. 2009; Martinet et al. 2015), it remains unclear whether this effect exists at higher redshift. It is also possible that the disagreements in the literature are driven by the large cluster-to-cluster variations, sample selections, or methods used to derive the LF, as observed in most of the above-mentioned works.","Citation Text":["De Propris et al. 2013"],"Citation Start End":[[1305,1327]]} {"Identifier":"2019ApJ...880..119CDe_Propris_et_al._(2013)_Instance_2","Paragraph":"The extent of the evolution of the faint red-sequence population, however, is still under debate. As opposed to local clusters that exhibit a flat faint end, or even an upturn at the faint end of their red-sequence LFs (e.g., Popesso et al. 2006; Agulli et al. 2014; Moretti et al. 2015; Lan et al. 2016), various studies have revealed that clusters at intermediate and high redshifts show a continual decrease in the fraction of the faint red-sequence population with redshift, which indicates a gradual buildup of the faint red-sequence population over time since z ∼ 1.5 (e.g., Dressler et al. 1997; Smail et al. 1998; De Lucia et al. 2004, 2007; Kodama et al. 2004; Tanaka et al. 2007; Gilbank et al. 2008; Rudnick et al. 2009, 2012; Stott et al. 2009; Martinet et al. 2015; Zenteno et al. 2016; Sarron et al. 2018; Zhang et al. 2019). This is also supported by findings that cluster galaxies on the high-mass end of the red sequence are on average older than those on the low-mass end (e.g., Nelan et al. 2005; Sánchez-Blázquez et al. 2009; Demarco et al. 2010a; Smith et al. 2012). Contrary to the above-mentioned studies, a number of studies have reported that there is little or no evolution of the faint end of the red-sequence cluster LF up to z ∼ 1.5 (e.g., Andreon 2006; Crawford et al. 2009; De Propris et al. 2013, 2015; Andreon et al. 2014; Cerulo et al. 2016), which in turn suggests the early formation of the faint end, similar to bright red-sequence galaxies. De Propris et al. (2013) proposed that the discrepancy is primarily caused by surface brightness selection effects, which lowers the detectability of faint galaxies at high redshift. Nevertheless, a recent study by Martinet et al. (2017) extensively investigated the effect of surface brightness dimming with 16 CLASH clusters in the redshift range of 0.2 z 0.6. They concluded that surface brightness dimming alone could not explain the observed redshift evolution of the faint end. Other possible explanations of the discrepancy invoke the radial and mass dependence of the faint red-sequence population, both of which are also debated in local cluster LF studies (see, e.g., Popesso et al. 2006; Barkhouse et al. 2007; Lan et al. 2016). While there may be a (weak) dependence of the red-sequence LF on cluster mass (or cluster properties that are mass proxies) at intermediate redshift (e.g., De Lucia et al. 2007; Muzzin et al. 2007; Rudnick et al. 2009; Martinet et al. 2015), it remains unclear whether this effect exists at higher redshift. It is also possible that the disagreements in the literature are driven by the large cluster-to-cluster variations, sample selections, or methods used to derive the LF, as observed in most of the above-mentioned works.","Citation Text":["De Propris et al. (2013)"],"Citation Start End":[[1479,1503]]} {"Identifier":"2022ApJ...927..237I__Shakura_&_Sunyaev_1973_Instance_1","Paragraph":"In our axisymmetric simulations without magnetohydrodynamical (MHD) effects, angular momentum transport in the accreting flow is given by imposing explicit viscosity. The viscous stress tensor is given by\n11\n\n\n\nσij=ρν˜∂vj∂xi+∂vi∂xj−23(∇·v)δij,\n\nwhere \n\n\n\nν˜\n\n is the shear viscosity, and the bulk viscosity is neglected. To mimic angular momentum transport associated with MHD turbulence driven by the magnetorotational instability (MRI) in a sufficiently ionized disk (e.g., Balbus & Hawley 1998; Stone & Pringle 2001; McKinney & Gammie 2004; Bai 2011; Narayan et al. 2012), we assume the azimuthal components of the shear tensor are nonzero and, in spherical polar coordinates, are given by\n12\n\n\n\nσrϕ=ρν˜∂∂rvϕr,\n\n\n\n13\n\n\n\nσθϕ=ρν˜sinθr∂∂θvϕsinθ\n\n(e.g., Stone et al. 1999; Fernández & Metzger 2013; Inayoshi et al. 2019). The strength of anomalous shear viscosity is calculated with the α-prescription (Shakura & Sunyaev 1973),\n14\n\n\n\nν˜=αcs2ΩK·exp−∣z∣H,\n\nwhere α is the viscous parameter, c\ns is the sound speed, \n\n\n\nΩK≡(GM•\/r3)1\/2\n\n, and H( ≡ c\ns\/ΩK) is the disk scale height. Note that the exponential factor imposes that the viscous process is active near the mid-plane. The strength of viscosity is set to\n15\n\n\n\nα=α0+αmaxexp−ρcritρ2.\n\nThe first term corresponds to the strength of MRI turbulence, and the value is set to α\n0 = 0.01 (e.g., Zhu & Stone 2018; Takasao et al. 2018). The second term characterizes the torque caused by non-axisymmetric structure (e.g., spiral arms) excited in a marginally unstable disk against its self-gravity. The density threshold, above which viscosity turns on, is assumed to be \n\n\n\nρcrit≡ΩK2\/(πG)≃2.2×10−21\n\n\n\n\n\n\n(M•\/105M⊙)(r\/10pc)−3gcm−3\n\n. This choice is motivated by the following reasons. The local gravitational instability of a rotating disk is described by Toomre’s Q parameter (Toomre 1964) defined by\n16\n\n\n\nQ≡csκΩπGΣ,\n\nwhere \n\n\n\nκΩ2=4Ω2+dΩ2\/dlnr\n\n is the epicyclic frequency, and Σ is the disk surface density. For a geometrically thin cold disk around a point mass, the Q-value is approximated to \n\n\n\nQ≃ΩK2\/(2πGρ)=0.5(ρcrit\/ρ)\n\n. Thus, the second term of the right-hand side of Equation (15) is written as \n\n\n\n∝exp(−4Q2)\n\n, which is a commonly used parameterization of the effective viscosity adopted in semi-analytical models of a self-gravitating disk; \n\n\n\n∝exp(−QA\/B)\n\n where A > 0 and B > 0 (Zhu et al. 2009; Takahashi et al. 2013; see also Kratter & Lodato 2016). The value of \n\n\n\nαmax\n\n depends on the level of non-axisymmetric structures in a disk. A previous three-dimensional RHD simulation study of a dusty circumnuclear disk around a BH shows that the mass inflow velocity is as high as a substantial fraction of the freefall velocity due to strong torque caused by spiral arms in the disk, indicating \n\n\n\nαmax≃O(1)\n\n (Toyouchi et al.2021). We here adopt \n\n\n\nαmax=2\n\n (Hirano et al. 2014; Fukushima et al. 2020). The critical Q-value for the onset of gravitational torque caused by spiral arms in a disk is considered to be Q ∼ 1, but the exact value depends on various properties of the disk (e.g., cooling, heating, and disk irradiation). We note that in our viscous model, the second term in Equation (15) becomes larger than α\n0 when Q ≤ 1.15.","Citation Text":["Shakura & Sunyaev 1973"],"Citation Start End":[[902,924]]} {"Identifier":"2017ApJ...834..103K__Matteo_et_al._1999_Instance_1","Paragraph":"Bright arc-like structures extending from the Sun, when seen in extreme-ultraviolet (EUV) wavelengths, are called coronal loops. Being a characteristic feature of the corona, it is important to assimilate high-resolution information on these structures in order to understand how plasma in the outer atmosphere is heated to multi-million Kelvin temperatures. The plasma temperatures and pressures are known to vary along the lengths of the loops, whose gradients provide some insight on the underlying heating mechanisms (Rosner et al. 1978), but the main attribute of critical importance is the cross-field morphology (Patsourakos & Klimchuk 2007). It has been suggested that coronal loops consist of multiple unresolved thin strands (Reale 2014; Klimchuk 2015). Observational evidence demonstrating low filling factors (Di Matteo et al. 1999), different degrees of “fuzziness” observed in loops at different temperatures (Tripathi et al. 2009; Reale et al. 2011), and plasma dynamics at small spatial scales (Antolin & Rouppe van der Voort 2012) indicate that this scenario is likely to be true. The typical cross-sections of the strands were estimated to be a few tens to a few hundreds of kilometers (DeForest 2007; Antolin & Rouppe van der Voort 2012; Brooks et al. 2013; Klimchuk 2015). Possible braiding of these strands can instigate magnetic reconnection, thus releasing significant energy to directly heat the plasma inside the loop (Cirtain et al. 2013; Klimchuk 2015). Each strand is believed to be impulsively and independently heated, leading to a multithermal configuration across the loop (Cargill 1994; Reale et al. 2005; Klimchuk et al. 2008; Tripathi et al. 2011). However, not all studies are consistent with this scenario since some loops demonstrate isothermal structuring (Del Zanna & Mason 2003; Noglik et al. 2008; Schmelz et al. 2009). One of the main issues plaguing observations of coronal loops is the intrinsic optically thin emission (Del Zanna & Mason 2003; Terzo & Reale 2010). Since the observed intensities are integrated along the line of sight, it becomes difficult to exclude emission from overlapping structures, which can be formed at different temperatures and inadvertently imply a multithermal structure. In this letter, we use a unique set of observations to reveal the multi-stranded and multithermal nature of a coronal loop, and isolate two of its components through the application of MHD seismology. More importantly, our results are free from the adverse effects arising from line of sight integrations.","Citation Text":["Di Matteo et al. 1999"],"Citation Start End":[[822,843]]} {"Identifier":"2017ApJ...834..103KTripathi_et_al._2011_Instance_1","Paragraph":"Bright arc-like structures extending from the Sun, when seen in extreme-ultraviolet (EUV) wavelengths, are called coronal loops. Being a characteristic feature of the corona, it is important to assimilate high-resolution information on these structures in order to understand how plasma in the outer atmosphere is heated to multi-million Kelvin temperatures. The plasma temperatures and pressures are known to vary along the lengths of the loops, whose gradients provide some insight on the underlying heating mechanisms (Rosner et al. 1978), but the main attribute of critical importance is the cross-field morphology (Patsourakos & Klimchuk 2007). It has been suggested that coronal loops consist of multiple unresolved thin strands (Reale 2014; Klimchuk 2015). Observational evidence demonstrating low filling factors (Di Matteo et al. 1999), different degrees of “fuzziness” observed in loops at different temperatures (Tripathi et al. 2009; Reale et al. 2011), and plasma dynamics at small spatial scales (Antolin & Rouppe van der Voort 2012) indicate that this scenario is likely to be true. The typical cross-sections of the strands were estimated to be a few tens to a few hundreds of kilometers (DeForest 2007; Antolin & Rouppe van der Voort 2012; Brooks et al. 2013; Klimchuk 2015). Possible braiding of these strands can instigate magnetic reconnection, thus releasing significant energy to directly heat the plasma inside the loop (Cirtain et al. 2013; Klimchuk 2015). Each strand is believed to be impulsively and independently heated, leading to a multithermal configuration across the loop (Cargill 1994; Reale et al. 2005; Klimchuk et al. 2008; Tripathi et al. 2011). However, not all studies are consistent with this scenario since some loops demonstrate isothermal structuring (Del Zanna & Mason 2003; Noglik et al. 2008; Schmelz et al. 2009). One of the main issues plaguing observations of coronal loops is the intrinsic optically thin emission (Del Zanna & Mason 2003; Terzo & Reale 2010). Since the observed intensities are integrated along the line of sight, it becomes difficult to exclude emission from overlapping structures, which can be formed at different temperatures and inadvertently imply a multithermal structure. In this letter, we use a unique set of observations to reveal the multi-stranded and multithermal nature of a coronal loop, and isolate two of its components through the application of MHD seismology. More importantly, our results are free from the adverse effects arising from line of sight integrations.","Citation Text":["Tripathi et al. 2011"],"Citation Start End":[[1661,1681]]} {"Identifier":"2017ApJ...834..103KTerzo_&_Reale_2010_Instance_1","Paragraph":"Bright arc-like structures extending from the Sun, when seen in extreme-ultraviolet (EUV) wavelengths, are called coronal loops. Being a characteristic feature of the corona, it is important to assimilate high-resolution information on these structures in order to understand how plasma in the outer atmosphere is heated to multi-million Kelvin temperatures. The plasma temperatures and pressures are known to vary along the lengths of the loops, whose gradients provide some insight on the underlying heating mechanisms (Rosner et al. 1978), but the main attribute of critical importance is the cross-field morphology (Patsourakos & Klimchuk 2007). It has been suggested that coronal loops consist of multiple unresolved thin strands (Reale 2014; Klimchuk 2015). Observational evidence demonstrating low filling factors (Di Matteo et al. 1999), different degrees of “fuzziness” observed in loops at different temperatures (Tripathi et al. 2009; Reale et al. 2011), and plasma dynamics at small spatial scales (Antolin & Rouppe van der Voort 2012) indicate that this scenario is likely to be true. The typical cross-sections of the strands were estimated to be a few tens to a few hundreds of kilometers (DeForest 2007; Antolin & Rouppe van der Voort 2012; Brooks et al. 2013; Klimchuk 2015). Possible braiding of these strands can instigate magnetic reconnection, thus releasing significant energy to directly heat the plasma inside the loop (Cirtain et al. 2013; Klimchuk 2015). Each strand is believed to be impulsively and independently heated, leading to a multithermal configuration across the loop (Cargill 1994; Reale et al. 2005; Klimchuk et al. 2008; Tripathi et al. 2011). However, not all studies are consistent with this scenario since some loops demonstrate isothermal structuring (Del Zanna & Mason 2003; Noglik et al. 2008; Schmelz et al. 2009). One of the main issues plaguing observations of coronal loops is the intrinsic optically thin emission (Del Zanna & Mason 2003; Terzo & Reale 2010). Since the observed intensities are integrated along the line of sight, it becomes difficult to exclude emission from overlapping structures, which can be formed at different temperatures and inadvertently imply a multithermal structure. In this letter, we use a unique set of observations to reveal the multi-stranded and multithermal nature of a coronal loop, and isolate two of its components through the application of MHD seismology. More importantly, our results are free from the adverse effects arising from line of sight integrations.","Citation Text":["Terzo & Reale 2010"],"Citation Start End":[[1990,2008]]} {"Identifier":"2017ApJ...834..103KReale_2014_Instance_1","Paragraph":"Bright arc-like structures extending from the Sun, when seen in extreme-ultraviolet (EUV) wavelengths, are called coronal loops. Being a characteristic feature of the corona, it is important to assimilate high-resolution information on these structures in order to understand how plasma in the outer atmosphere is heated to multi-million Kelvin temperatures. The plasma temperatures and pressures are known to vary along the lengths of the loops, whose gradients provide some insight on the underlying heating mechanisms (Rosner et al. 1978), but the main attribute of critical importance is the cross-field morphology (Patsourakos & Klimchuk 2007). It has been suggested that coronal loops consist of multiple unresolved thin strands (Reale 2014; Klimchuk 2015). Observational evidence demonstrating low filling factors (Di Matteo et al. 1999), different degrees of “fuzziness” observed in loops at different temperatures (Tripathi et al. 2009; Reale et al. 2011), and plasma dynamics at small spatial scales (Antolin & Rouppe van der Voort 2012) indicate that this scenario is likely to be true. The typical cross-sections of the strands were estimated to be a few tens to a few hundreds of kilometers (DeForest 2007; Antolin & Rouppe van der Voort 2012; Brooks et al. 2013; Klimchuk 2015). Possible braiding of these strands can instigate magnetic reconnection, thus releasing significant energy to directly heat the plasma inside the loop (Cirtain et al. 2013; Klimchuk 2015). Each strand is believed to be impulsively and independently heated, leading to a multithermal configuration across the loop (Cargill 1994; Reale et al. 2005; Klimchuk et al. 2008; Tripathi et al. 2011). However, not all studies are consistent with this scenario since some loops demonstrate isothermal structuring (Del Zanna & Mason 2003; Noglik et al. 2008; Schmelz et al. 2009). One of the main issues plaguing observations of coronal loops is the intrinsic optically thin emission (Del Zanna & Mason 2003; Terzo & Reale 2010). Since the observed intensities are integrated along the line of sight, it becomes difficult to exclude emission from overlapping structures, which can be formed at different temperatures and inadvertently imply a multithermal structure. In this letter, we use a unique set of observations to reveal the multi-stranded and multithermal nature of a coronal loop, and isolate two of its components through the application of MHD seismology. More importantly, our results are free from the adverse effects arising from line of sight integrations.","Citation Text":["Reale 2014"],"Citation Start End":[[736,746]]} {"Identifier":"2016MNRAS.461.2480M__Zurek_&_Benz_1986_Instance_1","Paragraph":"In this section we show that the growth of the m = 1 mode in the disc results in the formation of a spiral density wave with a constant global pattern speed ΩP. As the disc is differentially rotating this means that there is a location in the disc, the so-called corotation radius rco, where the spiral density wave has the same orbital velocity as the fluid in the disc. Inside rco the wave travels slower than the fluid, which means that it has negative angular momentum with respect to the fluid. While the wave amplitude is linear, it does not interact with the fluid, but once non-linear amplitude effects come into play, the spiral density wave can couple to the fluid via dissipation (Papaloizou & Lin 1995; Goodman & Rafikov 2001; Heinemann & Papaloizou 2012). When this happens, the wave begins to transport angular momentum outwards as the fluid loses angular momentum to the wave inside the corotation radius. The development and persistence of the spiral density wave are shown in Fig. 3. The figure shows the fractional change in density between two successive snapshots of the tracer particles Δρ\/ρ at nine different times of the disc evolution, as well as the tracer particles that are located at rco (grey circles). The location of the corotation radius is defined as the radius where the m = 1 pattern speed and the fluid orbital velocity are equal. As usual, the non-axisymmetric modes in the disc are analysed by means of an azimuthal Fourier transform of the rest-mass density ρ (Zurek & Benz 1986; Heemskerk et al. 1992):\n\n(5)\n\n\\begin{equation}\nD_m = \\int \\, \\alpha \\, \\sqrt{\\gamma } \\,\\rho \\, {\\rm e}^{-i\\,m\\,\\phi } \\, d^3x \\,,\n\\end{equation}\n\nwith α and γ being the space–time lapse function and the determinant of the three-dimensional metric, respectively. Similarly, the mode analysis performed using the tracers is accomplished by means of the following sum\n\n(6)\n\n\\begin{equation}\nD_m = \\sum _j^N \\, m_j \\, {\\rm e}^{-i\\,m\\,\\phi },\n\\end{equation}\n\nwhere mj is the mass of each tracer particle. From the mode amplitudes, the pattern speed of an azimuthal mode with mode number m is defined as (see e.g. Heemskerk et al. 1992)\n\n(7)\n\n\\begin{equation}\n\\Omega _{\\rm P} = \\frac{1}{m}\\frac{d \\phi _m}{dt},\n\\end{equation}\n\nwhere the phase angle ϕm is given by\n\n(8)\n\n\\begin{equation}\n\\phi _m = \\mathrm{tan}^{-1} \\left(\\frac{\\mathrm{Im}(-D_m)}{\\mathrm{Re}(D_m)} \\right).\n\\end{equation}\n\nFor our simulation, we obtain an orbital period of the m = 1 pattern of PP ∼ 1.96 ms, which is slightly shorter than twice the initial orbital period of the disc at the location of the density maximum (see Table 1). We note that we have chosen the same range of the fractional change in the rest-mass density in all snapshots shown in Fig. 3, which corresponds to the interval [−0.1, 0.1]. At these wave amplitudes, non-linear effects are negligible compared to the linear effects (Masset & Tagger 1997). This plot range has, however, been chosen for visualization purposes and the wave amplitudes are actually much larger than 0.1 after the saturation of the m = 1 growth, reaching almost unity. At these wave amplitudes non-linear effects are important and the spiral density wave can couple to the fluid via dissipation. To show the development of weak shocks, we plot the fractional change in the entropy S = p\/ρΓ for tracers with Δρ\/ρ > 0.1 in Fig. 4. From this plot, we clearly see an increase in the fluid entropy in the inner and outer regions of the spiral density wave. In some snapshots of Fig. 3, we can see fractional changes in ρ in the form of two spiral arms in the inner regions of the disc. The dominant m = 1 mode developing in the disc should not produce these, which means there could be a different mechanism at play. Standing shocks in the inner regions of tilted accretion discs in the form of two spiral arms have been observed and analysed in Henisey, Blaes & Fragile (2012) and Generozov et al. (2014) and are a distinctive feature of tilted accretion discs. Finally, we note that the mesh refinement boundaries of our computational grid also produce entropy changes due to numerical dissipation. However, these changes are about an order of magnitude smaller than the physical increase of entropy due to the development of shocks in the spiral density wave.","Citation Text":["Zurek & Benz 1986"],"Citation Start End":[[1500,1517]]} {"Identifier":"2016ApJ...827...27Z__Parnell_et_al._1996_Instance_1","Paragraph":"In the context of a standard flare and coronal mass ejection (CME) model (e.g., Shibata et al. 1995; Lin et al. 2004), there are two parallel flare ribbons where nonthermal electrons collide and heat the chromosphere, which are observed in the Ca ii H, Hα, UV, and EUV wavelengths. Apart from the two ribbons, a particular type of flare ribbons, i.e., circular ribbons, exist (Masson et al. 2009; Reid et al. 2012; Wang & Liu 2012; Jiang et al. 2013; Liu et al. 2013; Sun et al. 2013; Yang et al. 2015; Zhang et al. 2015). They are always associated with the spine-fan configuration in the presence of the magnetic null point, which is a singular point where the magnetic field vanishes (\n\n\n\n\n\n = 0; Lau & Finn 1990). The magnetic field \n\n\n\n\n\n near the null point can be expressed as the linear term \n\n\n\n\n\n, where \n\n\n\n\n\n is a Jacobian matrix with elements \n\n\n\n\n\n and \n\n\n\n\n\n is the position vector \n\n\n\n\n\n centered at the null point (Parnell et al. 1996). The divergence-free condition (\n\n\n\n\n\n) requires that the sum of the three eigenvalues equals zero (Zhang et al. 2012). The two eigenvectors corresponding to the two eigenvalues of the same sign determine the fan surface, which divides the space into two regions having a distinct connectivity. The third eigenvector corresponding to the third eigenvalue of the opposite sign determines the direction of spines passing through the null point. Magnetic reconnection and particle acceleration in null point reconnection regions have been explored in analytical studies (Priest & Titov 1996; Litvinenko 2004) and three-dimensional (3D) numerical simulations (Rosdahl & Galsgaard 2010; Baumann et al. 2013a, 2013b). The circular ribbons are believed to be intersections of the fan surfaces and the chromosphere. The central or inner ribbons within the circular ribbons are thought to be intersections of the inner spines and the chromosphere (Reid et al. 2012; Wang & Liu 2012). Sometimes, there are multiple flare ribbons owing to the extraordinarily complex magnetic topology of the active regions (ARs; Joshi et al. 2015; Liu et al. 2015).","Citation Text":["Parnell et al. 1996"],"Citation Start End":[[932,951]]} {"Identifier":"2017MNRAS.470.3206C__Marcy_etal._2014_Instance_1","Paragraph":"Our motivation for this work is manifold. First, we have incorporated the gas-accretion models of Papaloizou Nelson (2005) into the combined N-body and protoplanetary disc evolution code presented in Coleman Nelson (2014, 2016a), in order to increase the realism of the planetary system formation simulations that can be computed with this numerical tool. The purpose of this paper is to provide a simplified examination of gas accretion on to isolated, non-interacting planetary cores at a variety of orbital locations using the evolving disc models from Coleman Nelson (2016a), as a precursor to presenting simulations that consider the contemporaneous accretion of solids and gas on to protoplanets under the influence of migration within the evolving disc models. A second motivation is to examine how accreting planets with different initial core masses at different locations in the disc evolve within disc lifetimes. Observations indicate the presence of exoplanets (super-Earths, Neptunes and Jupiters) that are likely to be gas bearing with a broad range of orbital radii, covering the interval 0.04au ap 100au (e.g. Marois etal. 2008; Borucki etal. 2011). Analysis of the occurrence rates as a function of planet radius in the Kepler data suggests that planets with radii in the range 0.85 Rp 4R are present around 50percent of Sun-like stars (e.g. Fressin etal. 2013), which is consonant with the results from earlier radial velocity surveys that focused on low-mass planets (Mayor etal. 2011). Transit timing variations (Wu Lithwick 2013; Hadden Lithwick 2016) and radial velocity measurements (Marcy etal. 2014; Weiss etal. 2016) indicate that the super-Earths and Neptunes in the Kepler data with radii Rp4R have masses in the range 2 Mp 15M, and show a tendency for the bulk density to increase for Rp1.5R and decrease for 1.5Rp4R, indicating that the smaller planets are composed almost entirely of solids, whereas the larger planets have larger radii due to the presence of significant gaseous envelopes that have been accreted during formation. Comparing theoretical models with the data suggests that the gaseous envelopes contribute little to the total masses of the super-Earths and Neptunes (Lopez Fortney 2014), with recent estimates indicating that planets with Rp 1.2R contain 1percent gas by mass, rising to 5percent for planets with Rp3R (Wolfgang Lopez 2015). Considering the gas giant exoplanets, numerous attempts have been made to constrain the core masses and total heavy element abundances of those transiting planets that have mass estimates from radial velocity measurements using evolutionary models of the internal structure (Guillot etal. 2006; Burrows etal. 2007; Miller Fortney 2011; Thorngren etal. 2016). These studies provide a strong indication that the majority of gas giant exoplanets are substantially enriched with heavy elements relative to their host stars, with heavy element masses typically being 20M or larger. These results are consistent with the idea that giant planets form when a sufficiently massive (i.e. in the range 1015M) core forms that is able to accrete gas and undergo runaway gas accretion sufficiently early in the disc lifetime, in basic agreement with the theoretical core accretion models. In the absence of a sufficiently massive core that forms early enough, a more common outcome is the formation of super-Earths or Neptunes that fail to become gas giants because of the relatively slow rate of gas accretion until the envelope mass becomes comparable to the core mass. It is clearly of interest to address the above observational results through theoretical modelling of in situ planet formation, and to compare the outcomes of our calculations with recent work that has considered gas accretion on to planets with short (Lee, Chiang Ormel 2014; Batygin, Bodenheimer Laughlin 2016) and long orbital periods (Piso Youdin 2014; Piso, Youdin Murray-Clay 2015). Our third motivation is to consider the longer term cooling and contraction of the gaseous envelopes for those planets that remain in a state of quasi-static equilibrium throughout the period of gas accretion when the disc is present. Since the observations are typically relevant to exoplanets that have existed around their stars for Gyrs, they will have evolved for time periods of this duration after the epoch of formation. This is the first time that our models have been used to examine this longer term evolution, and our approach is similar to that used in recent population synthesis studies (see the recent review by Mordasini etal. 2015).","Citation Text":["Marcy etal. 2014"],"Citation Start End":[[1616,1632]]} {"Identifier":"2016MNRAS.458..660H__Elíasdóttir_et_al._2007_Instance_1","Paragraph":"To study the effect that assuming light traces mass has, we use a model of a cluster based on real data that contains 174 small scale galaxy-scale haloes (spectroscopically identified by Grillo et al. 2015) embedded in two large, cluster-scale DM haloes (Jauzac et al. 2014; Grillo et al. 2015). In this study, we act only to study the effect of changes to the galaxy-scale haloes on the positions of multiple images. We use the position of multiple images in the Hubble Frontier Field (HFF) galaxy cluster, MACS J0416 and the best-fitting cluster model that fits these multiple images as derived by the parametric strong lensing algorithm lenstool (Jullo et al. 2007; Jauzac et al. 2014). This equates to 140 multiple images and 174 cluster members. Each potential was originally fitted with a pseudo-isothermal elliptical mass distribution (PIEMD; Kneib et al. 1996; Natarajan & Kneib 1997; Elíasdóttir et al. 2007; Jullo et al. 2007), which follows the analytical density profile,\n\n(1)\n\n\\begin{equation}\n\\frac{\\rho (r)}{\\rho _0} = \\frac{1}{\\sqrt{r^2+r_{\\rm core}^2}} - \\frac{1}{\\sqrt{r^2+r_{\\rm cut}^2}},\n\\end{equation}\n\nwhere r is the radial distance from the centre of the halo, and the profile is parametrized by the core radius, rcore, and the cut radius, rcut. The cluster itself has a measured mass within a 200 kpc aperture of (1.6 ± 0.01) × 1014 M⊙ (Jauzac et al. 2014), and the mass of each galaxy has a lognormal distribution centred around log(M\/M⊙) = 10.1 ± 0.6. The distribution of ellipticities peaks at 0.1 and decreases towards larger ellipticities. The galaxies span the entire range between 0 and 0.9. We split each galaxy halo potential into two components: a baryonic core and a DM halo. We separate the halo into two PIEMDs with the baryonic $r^{\\rm B}_{\\rm core} = r_{\\rm core}$. For the baryonic cut radius, we conservatively cut it to a quarter of the original cut radius $r^{\\rm B}_{\\rm cut} = \\frac {r_{\\rm cut}}{4}$ (Velander et al. 2014), although this could be smaller. We also force the dark matter core radius to the baryonic cut radius, $r^{\\rm DM}_{\\rm core} = r^{\\rm B}_{\\rm cut}$ and the dark matter cut radius as the original cut radius $r^{\\rm DM}_{\\rm cut} = r_{\\rm cut}$. Separating the halo like this means that the mass of each halo is conserved with respect to the pre-split halo. Given this two-component galaxy model, we project the images back to the source plane to create a list of background sources for the cluster. To do this, we use the same redshift information for the sources as that in Jauzac et al. (2014).","Citation Text":["Elíasdóttir et al. 2007"],"Citation Start End":[[893,916]]} {"Identifier":"2019MNRAS.490.2627W__Kormendy_&_Ho_2013_Instance_1","Paragraph":"From the scattering experiments, we have obtained the HVB distribution d3Nhvb\/(dmchirpdvejdτ). Note that this distribution varies with M1 and q, thus it is a function of mchirp, τ and veject but also of log M1 and log q. After the ejection, a given HVB will escape from the galactic potential with initial velocity vej and merge in the dark matter halo or in the IGM at a distance R away from the host galactic centre. This distance depends on the flight time τ, and can be computed explicitly by assuming a specific galactic potential. In this work, we adopt the characteristic galactic potential of elliptical galaxies (e.g. Kenyon et al. 2008, 2014),\n(19)$$\\begin{eqnarray*}\r\n\\phi (r)& =& \\phi _\\mathrm{bh}(r)+\\phi _b(r) + \\phi _h(r)\\nonumber\\\\\r\n&=& -\\frac{G(M_1+M_2)}{r} -\\frac{GM_\\mathrm{ b}}{r+r_\\mathrm{ b}} -\\frac{GM_\\mathrm{ h}}{r}\\ln \\left(1+\\frac{r}{r_\\mathrm{ h}}\\right),\r\n\\end{eqnarray*}$$where Mb is the mass of the bulge, Mh is the mass of the dark matter halo, rb is the scale radius of the bulge, and rh is the scale radius of the dark matter halo. The choice of the spherical potential in equation (19) is dictated by computational convenience, as it allows us to perform 1D calculations to compute the ejected CO binary trajectory. The addition of a disc component would produce a deflection of the ejected trajectories, without significantly affecting the overall distribution of distances travelled. We scale the variables Mb, Mh, rb, and rh with the total mass of the SMBHB M1(1 + q) by means of the relations (e.g. Kormendy & Ho 2013; Kulier & Ostriker 2015)\n(20)$$\\begin{eqnarray*}\r\n\\frac{M_1(q+1)}{10^9\\mathrm{ M}\\mathrm{ }_\\odot } &=& 0.49\\left(\\frac{M_b}{10^{11}\\mathrm{ M}_\\odot }\\right)^{1.16},\\nonumber\\\\\r\n\\frac{M_h}{10^{13}\\mathrm{ M}_\\odot } & = & 0.30\\left(\\frac{M_b}{10^{11}\\mathrm{ M}_\\odot}\\right),\\nonumber\\\\\r\n\\frac{M_b}{10^6 \\mathrm{ M}_\\odot }\\bigg (\\frac{\\mathrm{kpc}}{r_b}\\bigg)^3 &=& 4000, \\nonumber\\\\\r\n\\frac{M_h}{10^6 \\mathrm{ M}_\\odot }\\bigg (\\frac{ \\mathrm{kpc}}{r_h}\\bigg)^3 &=& 125.\r\n\\end{eqnarray*}$$The ejection properties are recorded at a distance of $r\\, \\sim \\, 50a_{\\mathrm{bh}}$, given the condition that the total energy of the compact binary must be positive. Thus, we can calculate the travelled distance R = D(M1(1 + q), τ, vej)\n(21)$$\\begin{eqnarray*}\r\n\\int _0^D\\frac{\\mathrm{ d}r}{\\sqrt{2E_0-2\\phi (r)- 2l_0^2\/r^2}} =\\int _0^{\\tau _\\mathrm{GW}} \\mathrm{ d}t,\r\n\\end{eqnarray*}$$where E0 and l0 are, respectively, the total energy and total angular momentum per unit mass at the time of ejection. The distribution of HVBs as a function of mass, travelling time τ, and distance from the galaxy centre at a merger distance R can then be calculated as\n(22)$$\\begin{eqnarray*}\r\n&& {\\frac{\\mathrm{d}^3 N_\\mathrm{hvb}}{\\mathrm{d}m_\\mathrm{chirp}\\mathrm{d}\\tau \\mathrm{d}R}(\\log q,\\log M_1,m_\\mathrm{chirp},\\tau ,R)}\\nonumber\\\\\r\n&& {\\quad=\\frac{\\mathrm{d}}{\\mathrm{d}R}\\oint _{D(M_1,q,\\tau ,v_\\mathrm{ej}) \\lt R}\\frac{\\mathrm{d}^3 N_\\mathrm{hvb}}{\\mathrm{d}m_\\mathrm{chirp}\\mathrm{d}v_\\mathrm{ej}\\mathrm{d}\\tau }\\mathrm{d}v_\\mathrm{ej}.}\r\n\\end{eqnarray*}$$Fig. 10 shows the 2D-PDF of the distance R and the corresponding velocity at that distance of the simulated HVBs. Note that not all ejected mergers can be observed within the age of the universe.","Citation Text":["Kormendy & Ho 2013"],"Citation Start End":[[1554,1572]]} {"Identifier":"2015ApJ...802L..14I__Melnick_et_al._2000b_Instance_1","Paragraph":"Observations of the lowest-lying rotational levels of water—those able to probe cold gas—have required space-based observatories. The Infrared Space Observatory-Short Wavelength Spectrometer (ISO-SWS; de Graauw et al. 1996; Kessler et al. 1996) covered the \n\n\n\n\n\n ro-vibrational band (symmetric bending mode) of H2O centered near 6 μm, and absorption out of the lowest-lying levels of the ortho and para nuclear spin modifications (1\n\n\n\n\n\n and 0\n\n\n\n\n\n, respectively) was detected toward several massive protostars (Boonman van Dishoeck 2003). Due to the low spectral resolution of the observing configuration though (\n\n\n\n\n\n using SWS in AOT6 grating mode), these lines were significantly blended with absorption from other nearby H2O lines, making the determination of level-specific column densities impossible. Instead, the entire \n\n\n\n\n\n band was fit simultaneously assuming a single temperature to determine the total water column density, \n\n\n\n\n\n. The Submillimeter Wave Astronomy Satellite (SWAS; Melnick et al. 2000b) provided much higher spectral resolution (\n\n\n\n\n\n km s−1) and covered the 1\n\n\n\n\n\n–1\n\n\n\n\n\n pure rotational transition of H2O at 557 GHz. This line was observed in both emission and absorption in multiple sources (e.g., Melnick et al. 2000a; Snell et al. 2000), demonstrating the ability to probe cold water. More recently, the study of low-lying rotational levels at high spectral resolution (∼0.5 km s−1) has been facilitated by the Heterodyne Instrument for the Far-Infrared (HIFI; de Graauw et al. 2010) on board the Herschel Space Observatory (Pilbratt et al. 2010). Water has been detected in both emission and absorption out of levels with \n\n\n\n\n\n in several protostars (e.g., van Dishoeck et al. 2011; van der Tak et al. 2013), and in absorption out of the 0\n\n\n\n\n\n and 1\n\n\n\n\n\n levels in the molecular ISM (e.g., Sonnentrucker et al. 2010; Flagey et al. 2013). Observations that resolve the velocity structure of absorption lines are vital to both determining level-specific column densities and understanding the dynamics of the absorbing\/emitting regions. This is especially important for protostars as such objects contain multiple dynamical components (e.g., disk, envelope, jets, outflows, shocks).","Citation Text":["Melnick et al. 2000b"],"Citation Start End":[[1002,1022]]} {"Identifier":"2018ApJ...865...22C__Viereck_et_al._2004_Instance_1","Paragraph":"Within this framework, Lovric et al. (2017) introduced a spectral color index in the solar UV that is linked to the ratio between the flux integrate over the Far-UV (FUV) and Middle-UV (MUV) spectral broadbands. Such a descriptor can be used to characterize UV stellar emission, which modulates the photochemistry of molecular species, e.g., oxygen, in the atmospheres of planets (e.g., Tian et al. 2014). By using solar irradiance measurements obtained with radiometers on board the Solar Radiation and Climate Experiment (SORCE) satellite (McClintock et al. 2005) for almost a solar cycle, the authors showed that the color index so defined is linearly correlated with the Bremen Magnesium II index, which is an excellent proxy of the magnetic activity (Viereck et al. 2004). Lovirc et a. showed that the correlation coefficient is slightly different for the descending phase of Cycle 23 and the ascending phase of the subsequent cycle. Such a difference was ascribed to residual instrumental effects, which, when compensated for, lead to a correlation coefficient constant with time. On the other hand, several solar photospheric and chromospheric indices present a clear asymmetry during different phases of a cycle (namely, an hysteresis pattern, e.g., Bachmann & White 1994; Criscuoli 2016; Salabert et al. 2017), whereas correlation coefficients between indices may vary from cycle to cycle (e.g., Bruevich & Yakunina 2014; Tapping & Morgan 2017), so that the question arises whether, and to what extent, the data corrections applied by Lovric et al. (2017) might include a physical variation of solar emission. The purposes of this paper are to answer this question and to investigate the physical mechanisms determining the high linear relation between the UV spectral color index and solar activity measured with the Mg ii index. To this aim, we compare the results of Lovric et al. (2017) with synthetic indices obtained with an irradiance reconstruction technique based on the use of semi-empirical atmosphere models and full-disk observations.","Citation Text":["Viereck et al. 2004"],"Citation Start End":[[756,775]]} {"Identifier":"2018ApJ...865...22CLovric_et_al._(2017)___Lovric_et_al._(2017)_Instance_1","Paragraph":"Within this framework, Lovric et al. (2017) introduced a spectral color index in the solar UV that is linked to the ratio between the flux integrate over the Far-UV (FUV) and Middle-UV (MUV) spectral broadbands. Such a descriptor can be used to characterize UV stellar emission, which modulates the photochemistry of molecular species, e.g., oxygen, in the atmospheres of planets (e.g., Tian et al. 2014). By using solar irradiance measurements obtained with radiometers on board the Solar Radiation and Climate Experiment (SORCE) satellite (McClintock et al. 2005) for almost a solar cycle, the authors showed that the color index so defined is linearly correlated with the Bremen Magnesium II index, which is an excellent proxy of the magnetic activity (Viereck et al. 2004). Lovirc et a. showed that the correlation coefficient is slightly different for the descending phase of Cycle 23 and the ascending phase of the subsequent cycle. Such a difference was ascribed to residual instrumental effects, which, when compensated for, lead to a correlation coefficient constant with time. On the other hand, several solar photospheric and chromospheric indices present a clear asymmetry during different phases of a cycle (namely, an hysteresis pattern, e.g., Bachmann & White 1994; Criscuoli 2016; Salabert et al. 2017), whereas correlation coefficients between indices may vary from cycle to cycle (e.g., Bruevich & Yakunina 2014; Tapping & Morgan 2017), so that the question arises whether, and to what extent, the data corrections applied by Lovric et al. (2017) might include a physical variation of solar emission. The purposes of this paper are to answer this question and to investigate the physical mechanisms determining the high linear relation between the UV spectral color index and solar activity measured with the Mg ii index. To this aim, we compare the results of Lovric et al. (2017) with synthetic indices obtained with an irradiance reconstruction technique based on the use of semi-empirical atmosphere models and full-disk observations.","Citation Text":["Lovric et al. (2017)","Lovric et al. (2017)"],"Citation Start End":[[23,43],[1544,1564]]} {"Identifier":"2018ApJ...865...22CLovric_et_al._(2017)_Instance_1","Paragraph":"Within this framework, Lovric et al. (2017) introduced a spectral color index in the solar UV that is linked to the ratio between the flux integrate over the Far-UV (FUV) and Middle-UV (MUV) spectral broadbands. Such a descriptor can be used to characterize UV stellar emission, which modulates the photochemistry of molecular species, e.g., oxygen, in the atmospheres of planets (e.g., Tian et al. 2014). By using solar irradiance measurements obtained with radiometers on board the Solar Radiation and Climate Experiment (SORCE) satellite (McClintock et al. 2005) for almost a solar cycle, the authors showed that the color index so defined is linearly correlated with the Bremen Magnesium II index, which is an excellent proxy of the magnetic activity (Viereck et al. 2004). Lovirc et a. showed that the correlation coefficient is slightly different for the descending phase of Cycle 23 and the ascending phase of the subsequent cycle. Such a difference was ascribed to residual instrumental effects, which, when compensated for, lead to a correlation coefficient constant with time. On the other hand, several solar photospheric and chromospheric indices present a clear asymmetry during different phases of a cycle (namely, an hysteresis pattern, e.g., Bachmann & White 1994; Criscuoli 2016; Salabert et al. 2017), whereas correlation coefficients between indices may vary from cycle to cycle (e.g., Bruevich & Yakunina 2014; Tapping & Morgan 2017), so that the question arises whether, and to what extent, the data corrections applied by Lovric et al. (2017) might include a physical variation of solar emission. The purposes of this paper are to answer this question and to investigate the physical mechanisms determining the high linear relation between the UV spectral color index and solar activity measured with the Mg ii index. To this aim, we compare the results of Lovric et al. (2017) with synthetic indices obtained with an irradiance reconstruction technique based on the use of semi-empirical atmosphere models and full-disk observations.","Citation Text":["Lovric et al. (2017)"],"Citation Start End":[[1879,1899]]} {"Identifier":"2020ApJ...891...81P__Jose_et_al._2013_Instance_1","Paragraph":"The MF is an important statistical tool to understand the formation of stars (Sharma et al. 2017 and references therein). The MF is often expressed by a power law, \n\n\n\n\n\n and the slope of the MF is given as \n\n\n\n\n\n, where N (log m) is the number of stars per unit logarithmic mass interval. We have used our deep optical data to generate the MF of the Sh 2-305 region. For this, we have utilized the optical V0 versus \n\n\n\n\n\n CMDs of the sources in the target region and that of the nearby field region of equal area and decontaminated the previous sources of foreground\/background stars and corrected for data incompleteness using a statistical subtraction method already described in detail in our previous papers (see Sharma et al. 2007, 2012, 2017; Pandey et al. 2008, 2013; Chauhan et al. 2011; Jose et al. 2013). As an example, in Figure 10 (left panel), we have shown the V0 versus \n\n\n\n\n\n CMDs for the stars lying within the central cluster “Mayer 3” in panel (a) and for those in the reference field region selected as an annular region outside the boundary of the Sh 2-305 region (see Section 3.1) in panel (b). The magnitudes were corrected for the AV values derived from the reddening map (see Section 3.7). In panel (c), we have plotted the statistically cleaned V0 versus \n\n\n\n\n\n CMD for the central cluster “Mayer 3,” which is showing the presence of PMS stars in the region. The ages and masses of the stars in this statistically cleaned CMD have been derived by applying the procedure described earlier in our previous papers (Chauhan et al. 2009; Sharma et al. 2017). For reference, the post-MS isochrone for 2 Myr calculated by Marigo et al. (2008; thick blue curve) along with the PMS isochrones of 0.1 and 3.5 Myr (purple curves) and evolutionary tracks of different masses (red curves) by Siess et al. (2000) are also shown in panel (c). These isochrones are corrected for the distance of Sh 2-305 (3.7 kpc; see Section 3.3). The corresponding MF has subsequently been plotted in Figure 10 (right panel) for the central cluster “Mayer 3.” For this, we have used only those sources that have ages equivalent to the average age of the optically identified YSOs combined with error (i.e., \n\n\n\n\n\n; see Table 6). Our photometry is more than 90% complete up to V = 21.5 mag, which corresponds to the detection limit of a 0.8 M⊙ (see Figure 10(c)) PMS star of ≃1.8 Myr age embedded in the nebulosity of AV ≃ 3.0 mag (i.e., the average values for the optically detected YSOs; see Table 6). We have applied a similar approach to derive the MF of the southern clustering and the whole region of Sh 2-305 (see Section 3.1), and the corresponding values of their MF slopes in the mass range 1.5 M⊙ 6.6 are given in Table 7. The MF of the northern clustering cannot be determined due to an insignificant number of optically detected stars.","Citation Text":["Jose et al. 2013"],"Citation Start End":[[798,814]]} {"Identifier":"2016ApJ...822L...7W__Lyubarskii_&_Petrova_1998_Instance_1","Paragraph":"The characteristic frequency of curvature radiation is\n8\n\n\n\n\n\n\nν\n\n\ncurv\n\n\n=\n\n\n\n3\nc\n\n\nγ\n\n\n3\n\n\n\n\n4\nπ\nρ\n\n\n\n=\n2.4\n×\n\n\n10\n\n\n3\n\n\n\n\nγ\n\n\n3\n\n\n\n\nρ\n\n\n30\n\n\n−\n1\n\n\n\nHz\n,\n\n\nwhere \n\n\n\n\nρ\n=\n30\n\n\nρ\n\n\n30\n\n\n\n\n km is the curvature radius and \n\n\n\n\nγ\n\n\n is the Lorentz factor of an emitting electron. For a typical FRB, we have\n9\n\n\n\n\nγ\n=\n75\n\n\nρ\n\n\n30\n\n\n1\n\n\/\n\n3\n\n\n\n\nν\n\n\ncurv,9\n\n\n1\n\n\/\n\n3\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nν\n\n\ncurv,9\n\n\n=\n\n\nν\n\n\ncurv\n\n\n\n\/\n\n\n\n10\n\n\n9\n\n\n\nHz\n\n\n. We then discuss whether or not a photon can propagate through the plasma in the magnetosphere by considering three effects. First, the plasma frequency in the emission region is\n10\n\n\n\n\n\n\nν\n\n\np\n\n\n=\n\n\n\n1\n\n\n2\nπ\n\n\n\n\n\n\n\n\n\n\n4\nπ\n\n\nn\n\n\ne\n\n\n\n\ne\n\n\n2\n\n\n\n\n\n\nm\n\n\ne\n\n\n\n\n\n\n\n\n\n1\n\n\/\n\n2\n\n\n.\n\n\nIn a highly magnetized magnetosphere, the plasma effect is negligible if \n\n\n\n\n\n\nν\n\n\np\n\n\n\n\n\nγ\n\n\n1\n\n\/\n\n2\n\n\n\n\nν\n\n\ncurv\n\n\n\n\n (Lyubarskii & Petrova 1998), which is further written as\n11\n\n\n\n\n\n\na\n\n\n30\n\n\n>\n1.0\n\n\nB\n\n\n*\n,\n12\n\n\n2\n\n\/\n\n9\n\n\n\n\nγ\n\n\n2\n\n\n−\n2\n\n\/\n\n9\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n4\n\n\/\n\n9\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nγ\n\n\n2\n\n\n=\nγ\n\n\/\n\n\n\n10\n\n\n2\n\n\n\n\n and we have taken the electron density of the emission region to be roughly that of the acceleration region. Second, the cyclotron absorption in the magnetosphere is generally considered in pulsar physics, whose optical depth is given by Lyubarskii & Petrova (1998):\n12\n\n\n\n\n\n\nτ\n\n\ncyc\n\n\n≃\n2\n×\n\n\n10\n\n\n−\n3\n\n\n\n\nB\n\n\n*\n,\n12\n\n\n3\n\n\/\n\n5\n\n\n\n\nP\n\n\n*\n\n\n−\n9\n\n\/\n\n5\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n3\n\n\/\n\n5\n\n\n\n\nγ\n\n\n2\n\n\n−\n3\n\n\/\n\n5\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nP\n\n\n*\n\n\n=\n2\nπ\n\n\/\n\n\n\nΩ\n\n\n*\n\n\n\n\n and the electron number density outside of the flux tube (see Figure 1) has been assumed to be described by the Goldreich–Julian density. Thus, the cyclotron absorption can be ignored if \n\n\n\n\n\n\nP\n\n\n*\n\n\n>\n0.03\n\n\nB\n\n\n*\n,\n12\n\n\n1\n\n\/\n\n3\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n1\n\n\/\n\n3\n\n\n\n\nγ\n\n\n2\n\n\n−\n1\n\n\/\n\n3\n\n\n\n\n s. Third, the characteristic distance (l) of a photon due to the Thomson scattering is (Lyubarskii & Petrova 1998)\n13\n\n\n\n\nl\n=\n\n\n\n1\n\n\n(\n1\n−\n\n\nβ\n\n\ne\n\n\ncos\nθ\n)\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n\n\n\n\nσ\n\n\nT\n\n\n\n\n\n=\n\n\n\n1.5\n×\n\n\n10\n\n\n14\n\n\n\ncm\n\n\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n,\n10\n\n\n(\n1\n−\n\n\nβ\n\n\ne\n\n\ncos\nθ\n)\n\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nβ\n\n\ne\n\n\nc\n\n\n is the velocity of an electron, θ is the angle between the motion directions of the electron and photon, and \n\n\n\n\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n,\n10\n\n\n=\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n\n\n\n\/\n\n\n\n10\n\n\n10\n\n\n\n\n\ncm\n\n\n−\n3\n\n\n\n\n has been assumed to be the mean electron number density of the magnetosphere. The light cylinder RL for a pulsar with period P* is \n\n\n\n\n\n\nR\n\n\nL\n\n\n=\n\n\ncP\n\n\n*\n\n\n\n\/\n\n2\nπ\n=\n4.88\n×\n\n\n10\n\n\n9\n\n\n(\n\n\nP\n\n\n*\n\n\n\n\/\n\n1\n\ns\n)\n\ncm\n≪\nl\n\n\n. Therefore, we conclude that a photon with frequency of order 1 GHz can propagate freely through the magnetosphere.","Citation Text":["Lyubarskii & Petrova 1998"],"Citation Start End":[[829,854]]} {"Identifier":"2016ApJ...822L...7W__Lyubarskii_&_Petrova_1998_Instance_2","Paragraph":"The characteristic frequency of curvature radiation is\n8\n\n\n\n\n\n\nν\n\n\ncurv\n\n\n=\n\n\n\n3\nc\n\n\nγ\n\n\n3\n\n\n\n\n4\nπ\nρ\n\n\n\n=\n2.4\n×\n\n\n10\n\n\n3\n\n\n\n\nγ\n\n\n3\n\n\n\n\nρ\n\n\n30\n\n\n−\n1\n\n\n\nHz\n,\n\n\nwhere \n\n\n\n\nρ\n=\n30\n\n\nρ\n\n\n30\n\n\n\n\n km is the curvature radius and \n\n\n\n\nγ\n\n\n is the Lorentz factor of an emitting electron. For a typical FRB, we have\n9\n\n\n\n\nγ\n=\n75\n\n\nρ\n\n\n30\n\n\n1\n\n\/\n\n3\n\n\n\n\nν\n\n\ncurv,9\n\n\n1\n\n\/\n\n3\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nν\n\n\ncurv,9\n\n\n=\n\n\nν\n\n\ncurv\n\n\n\n\/\n\n\n\n10\n\n\n9\n\n\n\nHz\n\n\n. We then discuss whether or not a photon can propagate through the plasma in the magnetosphere by considering three effects. First, the plasma frequency in the emission region is\n10\n\n\n\n\n\n\nν\n\n\np\n\n\n=\n\n\n\n1\n\n\n2\nπ\n\n\n\n\n\n\n\n\n\n\n4\nπ\n\n\nn\n\n\ne\n\n\n\n\ne\n\n\n2\n\n\n\n\n\n\nm\n\n\ne\n\n\n\n\n\n\n\n\n\n1\n\n\/\n\n2\n\n\n.\n\n\nIn a highly magnetized magnetosphere, the plasma effect is negligible if \n\n\n\n\n\n\nν\n\n\np\n\n\n\n\n\nγ\n\n\n1\n\n\/\n\n2\n\n\n\n\nν\n\n\ncurv\n\n\n\n\n (Lyubarskii & Petrova 1998), which is further written as\n11\n\n\n\n\n\n\na\n\n\n30\n\n\n>\n1.0\n\n\nB\n\n\n*\n,\n12\n\n\n2\n\n\/\n\n9\n\n\n\n\nγ\n\n\n2\n\n\n−\n2\n\n\/\n\n9\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n4\n\n\/\n\n9\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nγ\n\n\n2\n\n\n=\nγ\n\n\/\n\n\n\n10\n\n\n2\n\n\n\n\n and we have taken the electron density of the emission region to be roughly that of the acceleration region. Second, the cyclotron absorption in the magnetosphere is generally considered in pulsar physics, whose optical depth is given by Lyubarskii & Petrova (1998):\n12\n\n\n\n\n\n\nτ\n\n\ncyc\n\n\n≃\n2\n×\n\n\n10\n\n\n−\n3\n\n\n\n\nB\n\n\n*\n,\n12\n\n\n3\n\n\/\n\n5\n\n\n\n\nP\n\n\n*\n\n\n−\n9\n\n\/\n\n5\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n3\n\n\/\n\n5\n\n\n\n\nγ\n\n\n2\n\n\n−\n3\n\n\/\n\n5\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nP\n\n\n*\n\n\n=\n2\nπ\n\n\/\n\n\n\nΩ\n\n\n*\n\n\n\n\n and the electron number density outside of the flux tube (see Figure 1) has been assumed to be described by the Goldreich–Julian density. Thus, the cyclotron absorption can be ignored if \n\n\n\n\n\n\nP\n\n\n*\n\n\n>\n0.03\n\n\nB\n\n\n*\n,\n12\n\n\n1\n\n\/\n\n3\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n1\n\n\/\n\n3\n\n\n\n\nγ\n\n\n2\n\n\n−\n1\n\n\/\n\n3\n\n\n\n\n s. Third, the characteristic distance (l) of a photon due to the Thomson scattering is (Lyubarskii & Petrova 1998)\n13\n\n\n\n\nl\n=\n\n\n\n1\n\n\n(\n1\n−\n\n\nβ\n\n\ne\n\n\ncos\nθ\n)\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n\n\n\n\nσ\n\n\nT\n\n\n\n\n\n=\n\n\n\n1.5\n×\n\n\n10\n\n\n14\n\n\n\ncm\n\n\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n,\n10\n\n\n(\n1\n−\n\n\nβ\n\n\ne\n\n\ncos\nθ\n)\n\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nβ\n\n\ne\n\n\nc\n\n\n is the velocity of an electron, θ is the angle between the motion directions of the electron and photon, and \n\n\n\n\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n,\n10\n\n\n=\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n\n\n\n\/\n\n\n\n10\n\n\n10\n\n\n\n\n\ncm\n\n\n−\n3\n\n\n\n\n has been assumed to be the mean electron number density of the magnetosphere. The light cylinder RL for a pulsar with period P* is \n\n\n\n\n\n\nR\n\n\nL\n\n\n=\n\n\ncP\n\n\n*\n\n\n\n\/\n\n2\nπ\n=\n4.88\n×\n\n\n10\n\n\n9\n\n\n(\n\n\nP\n\n\n*\n\n\n\n\/\n\n1\n\ns\n)\n\ncm\n≪\nl\n\n\n. Therefore, we conclude that a photon with frequency of order 1 GHz can propagate freely through the magnetosphere.","Citation Text":["Lyubarskii & Petrova (1998)"],"Citation Start End":[[1268,1295]]} {"Identifier":"2016ApJ...822L...7W__Lyubarskii_&_Petrova_1998_Instance_3","Paragraph":"The characteristic frequency of curvature radiation is\n8\n\n\n\n\n\n\nν\n\n\ncurv\n\n\n=\n\n\n\n3\nc\n\n\nγ\n\n\n3\n\n\n\n\n4\nπ\nρ\n\n\n\n=\n2.4\n×\n\n\n10\n\n\n3\n\n\n\n\nγ\n\n\n3\n\n\n\n\nρ\n\n\n30\n\n\n−\n1\n\n\n\nHz\n,\n\n\nwhere \n\n\n\n\nρ\n=\n30\n\n\nρ\n\n\n30\n\n\n\n\n km is the curvature radius and \n\n\n\n\nγ\n\n\n is the Lorentz factor of an emitting electron. For a typical FRB, we have\n9\n\n\n\n\nγ\n=\n75\n\n\nρ\n\n\n30\n\n\n1\n\n\/\n\n3\n\n\n\n\nν\n\n\ncurv,9\n\n\n1\n\n\/\n\n3\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nν\n\n\ncurv,9\n\n\n=\n\n\nν\n\n\ncurv\n\n\n\n\/\n\n\n\n10\n\n\n9\n\n\n\nHz\n\n\n. We then discuss whether or not a photon can propagate through the plasma in the magnetosphere by considering three effects. First, the plasma frequency in the emission region is\n10\n\n\n\n\n\n\nν\n\n\np\n\n\n=\n\n\n\n1\n\n\n2\nπ\n\n\n\n\n\n\n\n\n\n\n4\nπ\n\n\nn\n\n\ne\n\n\n\n\ne\n\n\n2\n\n\n\n\n\n\nm\n\n\ne\n\n\n\n\n\n\n\n\n\n1\n\n\/\n\n2\n\n\n.\n\n\nIn a highly magnetized magnetosphere, the plasma effect is negligible if \n\n\n\n\n\n\nν\n\n\np\n\n\n\n\n\nγ\n\n\n1\n\n\/\n\n2\n\n\n\n\nν\n\n\ncurv\n\n\n\n\n (Lyubarskii & Petrova 1998), which is further written as\n11\n\n\n\n\n\n\na\n\n\n30\n\n\n>\n1.0\n\n\nB\n\n\n*\n,\n12\n\n\n2\n\n\/\n\n9\n\n\n\n\nγ\n\n\n2\n\n\n−\n2\n\n\/\n\n9\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n4\n\n\/\n\n9\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nγ\n\n\n2\n\n\n=\nγ\n\n\/\n\n\n\n10\n\n\n2\n\n\n\n\n and we have taken the electron density of the emission region to be roughly that of the acceleration region. Second, the cyclotron absorption in the magnetosphere is generally considered in pulsar physics, whose optical depth is given by Lyubarskii & Petrova (1998):\n12\n\n\n\n\n\n\nτ\n\n\ncyc\n\n\n≃\n2\n×\n\n\n10\n\n\n−\n3\n\n\n\n\nB\n\n\n*\n,\n12\n\n\n3\n\n\/\n\n5\n\n\n\n\nP\n\n\n*\n\n\n−\n9\n\n\/\n\n5\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n3\n\n\/\n\n5\n\n\n\n\nγ\n\n\n2\n\n\n−\n3\n\n\/\n\n5\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nP\n\n\n*\n\n\n=\n2\nπ\n\n\/\n\n\n\nΩ\n\n\n*\n\n\n\n\n and the electron number density outside of the flux tube (see Figure 1) has been assumed to be described by the Goldreich–Julian density. Thus, the cyclotron absorption can be ignored if \n\n\n\n\n\n\nP\n\n\n*\n\n\n>\n0.03\n\n\nB\n\n\n*\n,\n12\n\n\n1\n\n\/\n\n3\n\n\n\n\nν\n\n\ncurv,9\n\n\n−\n1\n\n\/\n\n3\n\n\n\n\nγ\n\n\n2\n\n\n−\n1\n\n\/\n\n3\n\n\n\n\n s. Third, the characteristic distance (l) of a photon due to the Thomson scattering is (Lyubarskii & Petrova 1998)\n13\n\n\n\n\nl\n=\n\n\n\n1\n\n\n(\n1\n−\n\n\nβ\n\n\ne\n\n\ncos\nθ\n)\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n\n\n\n\nσ\n\n\nT\n\n\n\n\n\n=\n\n\n\n1.5\n×\n\n\n10\n\n\n14\n\n\n\ncm\n\n\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n,\n10\n\n\n(\n1\n−\n\n\nβ\n\n\ne\n\n\ncos\nθ\n)\n\n\n\n,\n\n\nwhere \n\n\n\n\n\n\nβ\n\n\ne\n\n\nc\n\n\n is the velocity of an electron, θ is the angle between the motion directions of the electron and photon, and \n\n\n\n\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n,\n10\n\n\n=\n\n\n\n\nn\n\n\n¯\n\n\n\n\ne\n\n\n\n\/\n\n\n\n10\n\n\n10\n\n\n\n\n\ncm\n\n\n−\n3\n\n\n\n\n has been assumed to be the mean electron number density of the magnetosphere. The light cylinder RL for a pulsar with period P* is \n\n\n\n\n\n\nR\n\n\nL\n\n\n=\n\n\ncP\n\n\n*\n\n\n\n\/\n\n2\nπ\n=\n4.88\n×\n\n\n10\n\n\n9\n\n\n(\n\n\nP\n\n\n*\n\n\n\n\/\n\n1\n\ns\n)\n\ncm\n≪\nl\n\n\n. Therefore, we conclude that a photon with frequency of order 1 GHz can propagate freely through the magnetosphere.","Citation Text":["Lyubarskii & Petrova 1998"],"Citation Start End":[[1853,1878]]} {"Identifier":"2019ApJ...885..108D__Sarazin_1986_Instance_1","Paragraph":"Our next goal is to estimate the density, spatial extent, and total baryonic mass contained in the CGM of NGC 3221, given that the detected signal is truly from NGC 3221. We calculate the average EM profile from the cumulative EI profile. As the EI of the larger annulus encompasses the EI of the smaller annulus, the uncertainties are not independent. We assume that the correlation coefficient of the consecutive measurements is 0.5, i.e., the covariance is half the geometric mean of their own variance: σi,i−1 = 0.5σiσi−1. We fit the EM profile with a β-model. The β-model has a density profile\n3\n\n\n\n\n\nwhere no is the central density and rc is the core radius, resulting in an EM profile similar to the surface brightness profile (Sarazin 1986)\n4\n\n\n\n\n\nwhere EMo is the central EM. Because of the small number of data points, large error bars, and the degeneracy between the parameters, we could not fit the three parameters of the β-model simultaneously. Therefore, as we did for the surface brightness profile in Section 3.1, we fit the EM profile in two different ways:\n\n(1)\nA β-model: We first fixed β = 0.5 and fit the radial profile for EMo and rc. Then, we fixed rc to the best-fit value (152.4 kpc) and fit for EMo and β. The resulting fit (χ2\/dof = 3.3\/4) yielded parameter values EMo =(2.8 ± 1.1) × 10−5 cm−6 kpc and β = 0.56 ± 0.36. We could not determine the range of rc from the fit, but we obtain the range of rc empirically for the best-fitted values of EMo and β that is consistent with the 1σ error span of the EM profile, with minimum rc = 110 kpc and maximum rc = 225 kpc. Interestingly, the best-fitted values and the confidence intervals are consistent with those obtained by fitting the radial profile of surface brightness in Section 3.1. Additionally, we fit the EM profile with Model B, a constant-density model.\n\n\n(2)\nA constant-density model: The truncated constant-density homogeneous medium (n = no(constant)) has an elliptical profile of projected EM,\n5\n\n\n\n\n\nwhere Rout is the spatial extent of the gaseous medium. We obtain best-fitted (χ2\/dof = 1.4\/4) values of n =\n\n\n\n\n\n = (2.7 ± 0.2) × 10−4 cm−3 and Rout = 175 ± 2 kpc (Figure 8).\n\n\n","Citation Text":["Sarazin 1986"],"Citation Start End":[[735,747]]} {"Identifier":"2018ApJ...865...71K__Will_&_Wiseman_1996_Instance_1","Paragraph":"The solution will be a retarded integral over the past light cone of the field point. The domain of the integration can be conveniently partitioned into a near-zone domain and a wave-zone domain. In the near zone, the field point distance from the source \n\n\n\n\n\n is small compared with a characteristic wavelength \n\n\n\n\n\n, where tc is the characteristic timescale of the dynamics of the source and c is the speed of light. The boundary of the near and wave zones is situated roughly at an arbitrary radius \n\n\n\n\n\n. This radius is of the same order of magnitude as λc. The integrals can vanish at this boundary. In fact, by partitioning the domain of integration into these two zones, all integrations will be finite, and one can show that the contributions from the near-zone spatial integrals containing \n\n\n\n\n\n (which diverge at \n\n\n\n\n\n) will be canceled by corresponding terms from the wave-zone integrals (Will & Wiseman 1996). As a result, this calculation does not depend on the arbitrary boundary radius \n\n\n\n\n\n. Keeping these facts in mind, one can find the PN metric as (Poisson & Will 2014)\n1\n\n\n\n\n\nwhere Ψ is defined as\n2\n\n\n\n\n\nPotentials that appear in the metric components are given by\n3\n\n\n\n\n\nwhere quantities in integrands are evaluated at time t and position \n\n\n\n\n\n. The matter variables in the PN approach are \n\n\n\n\n\n, where Σ* is the conserved surface mass density defined as\n4\n\n\n\n\n\nin which Σ is the proper surface density and g is the determinant of the metric tensor. Here u0 is the zeroth component of the velocity four-vector uα. It should be noted that in the Newtonian limit, there is no difference between Σ* and the proper surface density Σ. Moreover, p is the pressure, Π = \/Σ is the internal energy per unit mass, and vj is the fluid’s velocity field defined with respect to the time coordinate t. Note that is the proper surface density of internal energy and U is the gravitational potential for surface density Σ*. In the following subsection, we will introduce the Newtonian potential in terms of Σ. Using the PN metric and the conservation equation of the energy-momentum tensor, i.e., \n\n\n\n\n\n, one can find the PN equations of hydrodynamics (Poisson & Will 2014). In fact, in the 1pn approximation, the relativistic corrections appear as terms proportional to order c−2 in the equations. The continuity equation in the PN limit takes the following form:\n5\n\n\n\n\n\nIn the cylindrical coordinate system (R, φ, z), where the velocity is \n\n\n\n\n\n, Equation (5) is given by\n6\n\n\n\n\n\nMoreover, the Euler equation in the PN approximation can be written as follows:\n7\n\n\n\n\n\nThe terms inside the braces are PN corrections. In the 1pn approximation, we ignore terms proportional to order c−4 and higher. The left-hand side of Equation (7) can be written as \n\n\n\n\n\n. After some algebraic manipulations and using vector analysis in the cylindrical coordinate system, one can decompose Equation (7) to components R and φ. The R component of the Euler equation reads\n8\n\n\n\n\n\nAlso, the φ component of the Euler equation can be written as\n9\n\n\n\n\n\nIn order to have a complete set of differential equations, the abovementioned equations should be joined with the first law of thermodynamics and an equation of state (EOS). The first law of thermodynamics for a perfect fluid can be written as\n10\n\n\n\n\n\nOn the other hand, the pressure and density of the fluid can be related to each other via an EOS. A simple case suitable for astrophysical aims is the barotropic equation, given as\n11\n\n\n\n\n\nwhere the conserved surface density is\n12\n\n\n\n\n\n\n","Citation Text":["Will & Wiseman 1996"],"Citation Start End":[[905,924]]} {"Identifier":"2018AandA...615A.148D___1985_Instance_1","Paragraph":"We study here the Sco OB1 association (Figs. 1 and 2), using this and other techniques. The general properties of this large OB association, which spans almost 5° on the sky, and is surrounded by a ring-shaped HII region called Gum 55, are reviewed by Reipurth (2008). Its central cluster NGC 6231 contains several tens of OB stars, which have been extensively studied. On the other hand, many fewer studies, all recent, were devoted to the full mass spectrum, using optical photometry (Sung et al. 1998, 2013) and X-rays (Sana et al. 2006, 2007; Damiani et al. 2016; Kuhn et al. 2017a,b). The currently accepted distance of NGC 6231 is approximately 1580 pc, and its age is between 2and 8 Myr, with a significant intrinsic spread (Sung et al. 2013; Damiani et al. 2016). No ongoing star formation is known to occur therein, however. Approximately one degree North of the cluster, the loose cluster Trumpler 24 (Tr 24) also belongs to the association. There is little literature on this cluster (Seggewiss 1968; Heske & Wendker 1984, 1985; Fu et al. 2003, 2005) which unlike NGC 6231 lacks a well-defined center and covers about one square degree on the sky. Its age is 10 Myr according toHeske & Wendker (1984, 1985), who find several PMS stars, and its distance is 1570–1630 pc according to Seggewiss (1968). Other studies of the entire Sco OB1 association include MacConnell & Perry (1969 – Hα-emission stars), Schild et al. (1969 – spectroscopy), Crawford et al. (1971 – photometry), Laval (Laval 1972a,b – gas and star kinematics, respectively), van Genderen et al. (1984 – Walraven photometry), and Perry et al.(1991 – photometry). At the northern extreme of Sco OB1, the partially obscured HII region G345.45+1.50 and its less obscured neighbor IC4628 were studied by Laval (1972a), Caswell & Haynes (1987), López et al. (2011), and López-Calderón et al. (2016). They contain massive young stellar objects (YSOs; Mottram et al. 2007), maser sources (Avison et al. 2016), and the IRAS source 16562-3959 with its radio jet (Guzmán et al. 2010), outflow (Guzmán et al. 2011), and ionized wind (Guzmán et al. 2014), and are therefore extremely young (1 Myr or less). The distance of G345.45+1.50 was estimated as 1.9 kpc by Caswell & Haynes (1987), and 1.7 kpc by López et al. (2011), in fair agreement with distances of Sco OB1 stars. In Fig. 1 of Reipurth (2008) a strip of blue stars is visible, connecting NGC 6231 to the region of IC4628.","Citation Text":["Heske & Wendker","1985"],"Citation Start End":[[1012,1027],[1034,1038]]} {"Identifier":"2018AandA...615A.148D___1985_Instance_2","Paragraph":"We study here the Sco OB1 association (Figs. 1 and 2), using this and other techniques. The general properties of this large OB association, which spans almost 5° on the sky, and is surrounded by a ring-shaped HII region called Gum 55, are reviewed by Reipurth (2008). Its central cluster NGC 6231 contains several tens of OB stars, which have been extensively studied. On the other hand, many fewer studies, all recent, were devoted to the full mass spectrum, using optical photometry (Sung et al. 1998, 2013) and X-rays (Sana et al. 2006, 2007; Damiani et al. 2016; Kuhn et al. 2017a,b). The currently accepted distance of NGC 6231 is approximately 1580 pc, and its age is between 2and 8 Myr, with a significant intrinsic spread (Sung et al. 2013; Damiani et al. 2016). No ongoing star formation is known to occur therein, however. Approximately one degree North of the cluster, the loose cluster Trumpler 24 (Tr 24) also belongs to the association. There is little literature on this cluster (Seggewiss 1968; Heske & Wendker 1984, 1985; Fu et al. 2003, 2005) which unlike NGC 6231 lacks a well-defined center and covers about one square degree on the sky. Its age is 10 Myr according toHeske & Wendker (1984, 1985), who find several PMS stars, and its distance is 1570–1630 pc according to Seggewiss (1968). Other studies of the entire Sco OB1 association include MacConnell & Perry (1969 – Hα-emission stars), Schild et al. (1969 – spectroscopy), Crawford et al. (1971 – photometry), Laval (Laval 1972a,b – gas and star kinematics, respectively), van Genderen et al. (1984 – Walraven photometry), and Perry et al.(1991 – photometry). At the northern extreme of Sco OB1, the partially obscured HII region G345.45+1.50 and its less obscured neighbor IC4628 were studied by Laval (1972a), Caswell & Haynes (1987), López et al. (2011), and López-Calderón et al. (2016). They contain massive young stellar objects (YSOs; Mottram et al. 2007), maser sources (Avison et al. 2016), and the IRAS source 16562-3959 with its radio jet (Guzmán et al. 2010), outflow (Guzmán et al. 2011), and ionized wind (Guzmán et al. 2014), and are therefore extremely young (1 Myr or less). The distance of G345.45+1.50 was estimated as 1.9 kpc by Caswell & Haynes (1987), and 1.7 kpc by López et al. (2011), in fair agreement with distances of Sco OB1 stars. In Fig. 1 of Reipurth (2008) a strip of blue stars is visible, connecting NGC 6231 to the region of IC4628.","Citation Text":["Heske & Wendker","1985"],"Citation Start End":[[1190,1205],[1213,1217]]} {"Identifier":"2015MNRAS.449.1057G__Aggarwal_1983_Instance_1","Paragraph":"H α velocity dispersion. for Hα, the mass of ionized hydrogen is not a good estimate of the Hα intensity, since the emission decreases with increasing temperature. Here, we compute the Hα flux from two contributions, namely the recombination of ionized hydrogen and collisional excitation from the ground state to level n = 3. We have to neglect the contribution from H ii regions around young massive stars since these are not treated in the simulations. Collisional excitations to n > 3 represent a negligible contribution to the total Hα emission since transitions to these levels are significantly less likely (Anderson et al. 2000, 2002, but see also Péquignot & Tsamis 2005 and references therein). We compute mHα (dLHα) and Mtot,Hα (Ltot,Hα), required in equation (9), following the emissivity calculations for recombination and collisional excitation of Draine (2011), Dong & Draine (2011), and Kim et al. (2013b) (but see also Aggarwal 1983):\n\n(11)\n\n\\begin{equation}\n{\\rm d}L_{\\mathrm{H}\\alpha ,\\mathrm{R}}\\propto T_4^{-0.942-0.031\\ln (T_4)}n_\\mathrm{e} n_{\\mathrm{H\\small {II}}} {\\rm d}V\\,,\n\\end{equation}\n\n\n(12)\n\n\\begin{equation}\n{\\rm d}L_{\\mathrm{H}\\alpha ,\\mathrm{C}}\\propto \\frac{\\Gamma _{13}(T_\\mathrm{e})}{\\sqrt{T_\\mathrm{e}}}{\\rm e}^{\\frac{-12.1 \\mathrm{eV}}{k_\\mathrm{B} T_\\mathrm{e}}} n_\\mathrm{e} n_{\\mathrm{H\\small {I}}} {\\rm d}V\\,,\n\\end{equation}\n\nwhere T4 = T\/104 K, Te is the electron temperature, nj is the number density of species j in cm−3, dV is the zone volume, and\n\n(13)\n\n\\begin{eqnarray}\n\\Gamma _{13}(T_\\mathrm{e})&=&0.35-2.62\\times 10^{-7}T_\\mathrm{e}-8.15\\times 10^{-11}T_\\mathrm{e}^2\\nonumber\\\\\n&&+\\;6.19\\times 10^{-15}T_\\mathrm{e}^3.\n\\end{eqnarray}\n\nWe apply equation (12) only for cells with temperatures 4000 T 25 000 K assuming Te = T. We only consider this temperature range because emission at T 4000 K will be negligible, while we expect to find very little atomic hydrogen at T > 25 000 K. We also assume $n_\\mathrm{e}=n_{\\mathrm{H\\,\\small {II}}}$, which results in an ∼10 per cent error at most in regions where helium is ionized.","Citation Text":["Aggarwal 1983"],"Citation Start End":[[936,949]]} {"Identifier":"2017MNRAS.464.4895G__Drury,_Aharonian_&_Völk_1994_Instance_1","Paragraph":"SNRs are thought to be the dominant contributors to the Galactic CR flux up to the ‘knee’ at E = 1015 eV. The Galactic production rate of CRs can be explained if ηCR ∼ 10 per cent of the SN energy (ηCR is the cosmic ray acceleration efficiency and ESN ∼ 1051 erg) goes into accelerating CRs at SN blast waves (e.g. Aharonian 2004). Many middle-age SNRs (tSNR ∼ 105 yr) found in dense environments hosting GMCs have been observed as bright GeV and TeV sources. In fact, SNRs interacting with GMCs, as inferred from the detection of OH masers (e.g. Frail et al. 2013), constitute the dominant fraction of Galactic GeV SNRs (e.g. Thompson, Baldini & Uchiyama 2012). An estimate of the GeV\/TeV flux from the hadronic component can be obtained with simple arguments. At high energies (Eγ > 1 GeV), the γ-ray spectrum is spectrally similar to the parent distribution of CR protons (e.g. Aharonian & Atoyan 1996). Then, for a power-law distribution of CR protons\n\n(96)\n\r\n\\begin{equation}\r\nn_{\\rm p}(E_{\\rm p}) = K_{\\rm p}E_{\\rm p}^{-s_{\\rm p}}\r\n\\end{equation}\r\n\nwhere the normalization Kp is obtained by assuming that the CR energy density $U_{\\rm CR}\\sim 3\\eta _{\\rm CR}E_{\\rm SN}\/4\\pi R_{\\rm SNR}^3$ (e.g. Drury, Aharonian & Völk 1994), the γ-ray photon emissivity [phs−1 cm−3 erg−1] is (e.g. Aharonian 2004)\n\n(97)\n\r\n\\begin{equation}\r\nJ_{\\gamma} (E_\\gamma ) = \\int _{E_{\\rm p, min}}^\\infty \\frac{2cn_{\\rm GMC}\\sigma _{\\rm pp}(E_{\\rm p})\\eta _An_{\\rm p}(E_{\\rm p})}{\\sqrt{(E_{\\rm p}-m_{\\rm p}c^2)^2\\kappa _{\\pi} ^2-m_{\\pi} ^2c^4}}{\\rm d}E_{\\rm p}\r\n\\end{equation}\r\n\nwhere the threshold proton energy for π0 production is $E_{\\rm p, min} = m_{\\rm p}c^2+ \\kappa _{\\pi} ^{-1}(E_\\gamma + m_{\\pi} ^2c^4\/4E_\\gamma )$, mp and mπ are the proton and π0 masses, ηA ≃ 1.5 includes the contribution of nuclei other than protons towards the production of γ-rays (Dermer 1986), κπ = 0.17 is the mean fraction of proton's kinetic energy transferred to π0-meson per collision, and nGMC is the target proton number density (assumed uniform) in the GMC. The p–p inelastic collision cross-section is given by (e.g. Cheng & Romero 2004)\n\n(98)\n\r\n\\begin{equation}\r\n\\sigma _{\\rm pp}(E_{\\rm p}) \\approx 30 \\left[0.95+0.06\\ln \\left(\\frac{E_{\\rm p}}{\\rm GeV}\\right)\\right]\\,{\\rm mb}\r\n\\end{equation}\r\n\nwhich is assumed to vanish below proton kinetic energy Ep − mpc2 1 GeV. Since σpp only has a weak logarithmic dependence on proton energy, the γ-ray spectrum is expected to reproduce the spectrum of the parent proton population. The integrated γ-ray photon flux in the GeV-region for sp = 2.15, E1 = 1 GeV and E2 = 100 GeV is\n\n(99)\n\r\n\\begin{equation}\r\n\\Phi _\\gamma = \\int _{E_1}^{E_2}\\frac{J_\\gamma (E^{\\prime }_\\gamma )V_{\\rm TeV}}{4\\pi d^2} {\\rm d}E_\\gamma ^{\\prime } \\simeq 8.16\\times 10^{-10} A\\,{\\rm cm}^{-2}\\,{\\rm s}^{-1}\r\n\\end{equation}\r\n\nwhere $A = \\eta _{\\rm CR} E_{\\rm SN,51}n_{\\rm GMC}d_4^{-2}$. This agrees with the photon flux measured by Fermi (H.E.S.S. Collaboration 2015) in the (1–100) GeV region Φ ≈ 8.93 × 10−9 cm−2 s−1 for ηCR ∼ 0.1 and nGMC ∼ 109 cm−3. This is a reasonable estimate of the target proton number density in light of the fact that Tian et al. (2007) find a number density of ∼103 cm−3 for the GMC associated with W41 from 13CO observations.","Citation Text":["Drury, Aharonian & Völk 1994"],"Citation Start End":[[1201,1229]]} {"Identifier":"2018ApJ...865...71K__Poisson_&_Will_2014_Instance_1","Paragraph":"The solution will be a retarded integral over the past light cone of the field point. The domain of the integration can be conveniently partitioned into a near-zone domain and a wave-zone domain. In the near zone, the field point distance from the source \n\n\n\n\n\n is small compared with a characteristic wavelength \n\n\n\n\n\n, where tc is the characteristic timescale of the dynamics of the source and c is the speed of light. The boundary of the near and wave zones is situated roughly at an arbitrary radius \n\n\n\n\n\n. This radius is of the same order of magnitude as λc. The integrals can vanish at this boundary. In fact, by partitioning the domain of integration into these two zones, all integrations will be finite, and one can show that the contributions from the near-zone spatial integrals containing \n\n\n\n\n\n (which diverge at \n\n\n\n\n\n) will be canceled by corresponding terms from the wave-zone integrals (Will & Wiseman 1996). As a result, this calculation does not depend on the arbitrary boundary radius \n\n\n\n\n\n. Keeping these facts in mind, one can find the PN metric as (Poisson & Will 2014)\n1\n\n\n\n\n\nwhere Ψ is defined as\n2\n\n\n\n\n\nPotentials that appear in the metric components are given by\n3\n\n\n\n\n\nwhere quantities in integrands are evaluated at time t and position \n\n\n\n\n\n. The matter variables in the PN approach are \n\n\n\n\n\n, where Σ* is the conserved surface mass density defined as\n4\n\n\n\n\n\nin which Σ is the proper surface density and g is the determinant of the metric tensor. Here u0 is the zeroth component of the velocity four-vector uα. It should be noted that in the Newtonian limit, there is no difference between Σ* and the proper surface density Σ. Moreover, p is the pressure, Π = \/Σ is the internal energy per unit mass, and vj is the fluid’s velocity field defined with respect to the time coordinate t. Note that is the proper surface density of internal energy and U is the gravitational potential for surface density Σ*. In the following subsection, we will introduce the Newtonian potential in terms of Σ. Using the PN metric and the conservation equation of the energy-momentum tensor, i.e., \n\n\n\n\n\n, one can find the PN equations of hydrodynamics (Poisson & Will 2014). In fact, in the 1pn approximation, the relativistic corrections appear as terms proportional to order c−2 in the equations. The continuity equation in the PN limit takes the following form:\n5\n\n\n\n\n\nIn the cylindrical coordinate system (R, φ, z), where the velocity is \n\n\n\n\n\n, Equation (5) is given by\n6\n\n\n\n\n\nMoreover, the Euler equation in the PN approximation can be written as follows:\n7\n\n\n\n\n\nThe terms inside the braces are PN corrections. In the 1pn approximation, we ignore terms proportional to order c−4 and higher. The left-hand side of Equation (7) can be written as \n\n\n\n\n\n. After some algebraic manipulations and using vector analysis in the cylindrical coordinate system, one can decompose Equation (7) to components R and φ. The R component of the Euler equation reads\n8\n\n\n\n\n\nAlso, the φ component of the Euler equation can be written as\n9\n\n\n\n\n\nIn order to have a complete set of differential equations, the abovementioned equations should be joined with the first law of thermodynamics and an equation of state (EOS). The first law of thermodynamics for a perfect fluid can be written as\n10\n\n\n\n\n\nOn the other hand, the pressure and density of the fluid can be related to each other via an EOS. A simple case suitable for astrophysical aims is the barotropic equation, given as\n11\n\n\n\n\n\nwhere the conserved surface density is\n12\n\n\n\n\n\n\n","Citation Text":["Poisson & Will 2014"],"Citation Start End":[[1074,1093]]} {"Identifier":"2018ApJ...865...71K__Poisson_&_Will_2014_Instance_2","Paragraph":"The solution will be a retarded integral over the past light cone of the field point. The domain of the integration can be conveniently partitioned into a near-zone domain and a wave-zone domain. In the near zone, the field point distance from the source \n\n\n\n\n\n is small compared with a characteristic wavelength \n\n\n\n\n\n, where tc is the characteristic timescale of the dynamics of the source and c is the speed of light. The boundary of the near and wave zones is situated roughly at an arbitrary radius \n\n\n\n\n\n. This radius is of the same order of magnitude as λc. The integrals can vanish at this boundary. In fact, by partitioning the domain of integration into these two zones, all integrations will be finite, and one can show that the contributions from the near-zone spatial integrals containing \n\n\n\n\n\n (which diverge at \n\n\n\n\n\n) will be canceled by corresponding terms from the wave-zone integrals (Will & Wiseman 1996). As a result, this calculation does not depend on the arbitrary boundary radius \n\n\n\n\n\n. Keeping these facts in mind, one can find the PN metric as (Poisson & Will 2014)\n1\n\n\n\n\n\nwhere Ψ is defined as\n2\n\n\n\n\n\nPotentials that appear in the metric components are given by\n3\n\n\n\n\n\nwhere quantities in integrands are evaluated at time t and position \n\n\n\n\n\n. The matter variables in the PN approach are \n\n\n\n\n\n, where Σ* is the conserved surface mass density defined as\n4\n\n\n\n\n\nin which Σ is the proper surface density and g is the determinant of the metric tensor. Here u0 is the zeroth component of the velocity four-vector uα. It should be noted that in the Newtonian limit, there is no difference between Σ* and the proper surface density Σ. Moreover, p is the pressure, Π = \/Σ is the internal energy per unit mass, and vj is the fluid’s velocity field defined with respect to the time coordinate t. Note that is the proper surface density of internal energy and U is the gravitational potential for surface density Σ*. In the following subsection, we will introduce the Newtonian potential in terms of Σ. Using the PN metric and the conservation equation of the energy-momentum tensor, i.e., \n\n\n\n\n\n, one can find the PN equations of hydrodynamics (Poisson & Will 2014). In fact, in the 1pn approximation, the relativistic corrections appear as terms proportional to order c−2 in the equations. The continuity equation in the PN limit takes the following form:\n5\n\n\n\n\n\nIn the cylindrical coordinate system (R, φ, z), where the velocity is \n\n\n\n\n\n, Equation (5) is given by\n6\n\n\n\n\n\nMoreover, the Euler equation in the PN approximation can be written as follows:\n7\n\n\n\n\n\nThe terms inside the braces are PN corrections. In the 1pn approximation, we ignore terms proportional to order c−4 and higher. The left-hand side of Equation (7) can be written as \n\n\n\n\n\n. After some algebraic manipulations and using vector analysis in the cylindrical coordinate system, one can decompose Equation (7) to components R and φ. The R component of the Euler equation reads\n8\n\n\n\n\n\nAlso, the φ component of the Euler equation can be written as\n9\n\n\n\n\n\nIn order to have a complete set of differential equations, the abovementioned equations should be joined with the first law of thermodynamics and an equation of state (EOS). The first law of thermodynamics for a perfect fluid can be written as\n10\n\n\n\n\n\nOn the other hand, the pressure and density of the fluid can be related to each other via an EOS. A simple case suitable for astrophysical aims is the barotropic equation, given as\n11\n\n\n\n\n\nwhere the conserved surface density is\n12\n\n\n\n\n\n\n","Citation Text":["Poisson & Will 2014"],"Citation Start End":[[2168,2187]]} {"Identifier":"2015ApJ...809...28Y___2013_Instance_1","Paragraph":"There are many types of nonstationarity for a shock front, e.g., self-reformation (Lembège & Dawson 1987; Hada et al. 2003; Chapman et al. 2005; Matsukiyo & Scholer 2014), self-excited ripples (Winske & Quest 1988; Savoini & Lembège 1994; Lembège et al. 2004; Burgess & Scholer 2007), and pre-existing waves or turbulence (Giacalone 2005; Guo & Giacalone 2010), some of which likely cause the unexpected motions of the TS. These nonstationarities are predicted and observed by numerical simulations and satellite observations, respectively. The term “self-reformation” describes a process wherein the particles reflected by the shock ramp accumulate ahead of the shock and form a shock foot, which then grows and becomes the new ramp. The new ramp starts to reflect incident particles, and the process repeats. Self-reformation of the shock front was predicted by both hybrid simulations (Tiu et al. 2011; Hellinger & Trávnícek 2002; Lembège et al. 2009; Yuan et al. 2009; Su et al. 2012) and particle-in-cell (PIC) simulations (Lembège & Dawson 1987; Hada et al. 2003; Nishimura et al. 2003; Scholer et al. 2003; Lee et al. 2005a; Yang et al. 2009, 2013) for large Mach number and low \n\n\n\n\n\n shocks, where \n\n\n\n\n\n is the ratio of the thermal pressure of ions to the magnetic pressure. Even in the presence of PUIs, self-reformation occurs under some conditions (Chapman et al. 2005; Lee et al. 2005b; Oka et al. 2011; Yang et al. 2012a; Matsukiyo & Scholer 2014). For the heliospheric TS, the values of \n\n\n\n\n\n and the Mach number are relatively low and high, respectively. The TS is generally believed to be in the supercritical regime and probably undergoes self-reformation (Burlaga et al. 2008). Self-excited ripples are usually found in two-dimensional (2D) hybrid simulations (Thomas 1989; Burgess & Scholer 2007) and PIC simulations (Savoini & Lembège 1994; Lembège et al. 2009; Yang et al. 2012b). Shock front ripples are robust in three-dimensional (3D) hybrid simulations (Thomas 1989; Hellinger et al. 1996). The filament instability of the shock front found in high-dimensional simulations can also contribute to the shock front nonstationarity (Spitkovsky 2005; Guo & Giacalone 2013; Caprioli & Spitkovsky 2014). Not all of the simulations above include PUIs. By using the 2D Los Alamos hybrid simulation code with PUIs, Liu et al. (2010) studied the Alfvén-cyclotron and mirror modes excited in the near-TS heliosheath. The impact of the PUIs on the shock front ripples and self-reformation is not mentioned. It is expected that the density of PUIs at the TS is of the order of 20%–30% of the solar wind density (Richardson et al. 2008; Wu et al. 2009; Matsukiyo & Scholer 2014). The impact of such a high percentage of PUIs on the shock front ripples has not been studied yet. The relevance of the shock front ripples to the multiple TS crossings still remains unclear. A precise description of this influence would require at least a 2D full particle model.","Citation Text":["Yang et al.","2013"],"Citation Start End":[[1132,1143],[1150,1154]]} {"Identifier":"2022ApJ...936..180C__Landau_&_Lifshitz_1971_Instance_1","Paragraph":"However, in the case of stationary collisionless stellar systems with gravitomagnetic forces, the situation is not so simple, because while E is still an integral of motion, J\n\nz\n is not conserved along orbits and so it cannot be used as an isolating integral in the DF. Fortunately, the problem is solved as follows. As is well known, the Lagrangian (per unit mass) associated with Equation (30) is\n34\n\n\n\n=∥v∥22−(ϕ+A·v),\n\nwhere, at variance with the EM case (e.g., see Landau & Lifshitz 1971), the + sign in the generalized potential derives from the – sign in the gravitomagnetic Lorentz force. Suppose now that \nv\n = v\n\nφ\n(R, z)\ne\n\n\nφ\n, so that \nA\n = A\n\nφ\n(R, z)\ne\n\n\nφ\n from the results in Section 2.1. The Euler–Lagrange equations show immediately that J\n\nz\n is not conserved, but a second integral of motion exists, I\n2 = J\n\nz\n − RA\n\nφ\n. The Jeans theorem then in principle allows for a two-integral DF, f(E, I\n2), and an interesting question arises whether such a DF is consistent with the assumption of streaming motions with \nv\n = v\n\nφ\n(R, z)\ne\n\n\nφ\n used to prove the existence of I\n2. The answer is in the affirmative, and it is easy to prove that properties (1) and (2) mentioned above for systems supported by a f(E, J\n\nz\n) are preserved by the generalized f(E, I\n2), in particular the fact that v\n\nR\n = v\n\nz\n = 0. Therefore, the vertical and radial Jeans Equations (B2) for a stationary, axisymmetric two-integral system with gravitomagnetic forces, supported by a DF of the family f(E, I\n2), become\n35\n\n\n\n∂ρσ2∂z=−ρ∂ϕ∂z+jBR[j],j=ρvφ,∂ρσ2∂R−ρΔR=−ρ∂ϕ∂R−jBz[j],\n\nwhere \n\n\n\nΔ=vφ2¯−σ2\n\n, and in the isotropic rotator case \n\n\n\nΔ=vφ2\n\n. Finally, the azimuthal Jeans equation vanishes identically also in the gravitomagnetic case, as obvious from the last of Equations (B2). Notice how, at variance with the classical Newtonian case, now the vertical and radial velocity dispersions depend on the ordered rotational field v\n\nφ\n(R, z), yet to be determined.","Citation Text":["Landau & Lifshitz 1971"],"Citation Start End":[[471,493]]} {"Identifier":"2016AandA...588A.132T__Dokkum_et_al._(2013)_Instance_1","Paragraph":"We performed an accurate estimation of the physical properties derived from SED fitting (e.g., absolute magnitude, stellar mass, and star formation rate) and characterized each sample as a whole with the median of each of these properties. Figure 6 shows the median of the probability distribution of stellar mass, absolute magnitude, and star formation rate for the BJGKn 6 (red squares) samples as a function of redshift. In the stellar mass panel, the dashed line shows the evolution of the stellar mass for galaxies with present-day stellar masses of log (M∗) ≈ 10.7, such as our Milky Way galaxy. The data are taken from the analysis of the CANDELS survey by van Dokkum et al. (2013). The observed mass growth determined by van Dokkum et al. (2013), which slightly increase by a factor of 0.1 dex from z = 1 to z = 0.5, agrees well with the flat behavior found in this work. In the star formation rate panel, the dashed line shows the evolution of the implied star formation rate that is caused by the evolution of the stellar mass of galaxies with present-day stellar masses of log (M∗) ≈ 10.7, such as our Milky Way, also taken from van Dokkum et al. (2013). Our results are slightly lower, suggesting that the SFR is sufficient to account for the increment in stellar mass between z = 1 and z = 0.5 and that major mergers play a minor role in this redshift range. The evolution of the SFR and sSFR resembles the expected main-sequence behavior of star-forming galaxies (Rodighiero et al. 2011). The BJGK evolution from z ~ 1 to z = 0 of the B-band absolute luminosity agrees with the evolution measured by Tasca et al. (2014). They found that the contribution of disks to the total B-band luminosity decreases by 30% from z ~ 1 to z = 0, while for the BJGs the median B-band luminosity decreases by a factor of 0.5 dex. The distribution of galaxy ages obtained by iSEDfit has a large dispersion, but even so, its increment between two epochs corresponds to the Universe age increment indicated by the redshift. According to the models of Lagos et al. (2014), galaxies of properties similar to the BJGs host most of the neutral gas at 0.5 z 1.5. Hence the BJG samples contain tentative targets to sample the neutral gas with submillimeter surveys. ","Citation Text":["van Dokkum et al. (2013)"],"Citation Start End":[[664,688]]} {"Identifier":"2016AandA...588A.132T__Dokkum_et_al._(2013)_Instance_2","Paragraph":"We performed an accurate estimation of the physical properties derived from SED fitting (e.g., absolute magnitude, stellar mass, and star formation rate) and characterized each sample as a whole with the median of each of these properties. Figure 6 shows the median of the probability distribution of stellar mass, absolute magnitude, and star formation rate for the BJGKn 6 (red squares) samples as a function of redshift. In the stellar mass panel, the dashed line shows the evolution of the stellar mass for galaxies with present-day stellar masses of log (M∗) ≈ 10.7, such as our Milky Way galaxy. The data are taken from the analysis of the CANDELS survey by van Dokkum et al. (2013). The observed mass growth determined by van Dokkum et al. (2013), which slightly increase by a factor of 0.1 dex from z = 1 to z = 0.5, agrees well with the flat behavior found in this work. In the star formation rate panel, the dashed line shows the evolution of the implied star formation rate that is caused by the evolution of the stellar mass of galaxies with present-day stellar masses of log (M∗) ≈ 10.7, such as our Milky Way, also taken from van Dokkum et al. (2013). Our results are slightly lower, suggesting that the SFR is sufficient to account for the increment in stellar mass between z = 1 and z = 0.5 and that major mergers play a minor role in this redshift range. The evolution of the SFR and sSFR resembles the expected main-sequence behavior of star-forming galaxies (Rodighiero et al. 2011). The BJGK evolution from z ~ 1 to z = 0 of the B-band absolute luminosity agrees with the evolution measured by Tasca et al. (2014). They found that the contribution of disks to the total B-band luminosity decreases by 30% from z ~ 1 to z = 0, while for the BJGs the median B-band luminosity decreases by a factor of 0.5 dex. The distribution of galaxy ages obtained by iSEDfit has a large dispersion, but even so, its increment between two epochs corresponds to the Universe age increment indicated by the redshift. According to the models of Lagos et al. (2014), galaxies of properties similar to the BJGs host most of the neutral gas at 0.5 z 1.5. Hence the BJG samples contain tentative targets to sample the neutral gas with submillimeter surveys. ","Citation Text":["van Dokkum et al. (2013)"],"Citation Start End":[[729,753]]} {"Identifier":"2016AandA...588A.132T__Dokkum_et_al._(2013)_Instance_3","Paragraph":"We performed an accurate estimation of the physical properties derived from SED fitting (e.g., absolute magnitude, stellar mass, and star formation rate) and characterized each sample as a whole with the median of each of these properties. Figure 6 shows the median of the probability distribution of stellar mass, absolute magnitude, and star formation rate for the BJGKn 6 (red squares) samples as a function of redshift. In the stellar mass panel, the dashed line shows the evolution of the stellar mass for galaxies with present-day stellar masses of log (M∗) ≈ 10.7, such as our Milky Way galaxy. The data are taken from the analysis of the CANDELS survey by van Dokkum et al. (2013). The observed mass growth determined by van Dokkum et al. (2013), which slightly increase by a factor of 0.1 dex from z = 1 to z = 0.5, agrees well with the flat behavior found in this work. In the star formation rate panel, the dashed line shows the evolution of the implied star formation rate that is caused by the evolution of the stellar mass of galaxies with present-day stellar masses of log (M∗) ≈ 10.7, such as our Milky Way, also taken from van Dokkum et al. (2013). Our results are slightly lower, suggesting that the SFR is sufficient to account for the increment in stellar mass between z = 1 and z = 0.5 and that major mergers play a minor role in this redshift range. The evolution of the SFR and sSFR resembles the expected main-sequence behavior of star-forming galaxies (Rodighiero et al. 2011). The BJGK evolution from z ~ 1 to z = 0 of the B-band absolute luminosity agrees with the evolution measured by Tasca et al. (2014). They found that the contribution of disks to the total B-band luminosity decreases by 30% from z ~ 1 to z = 0, while for the BJGs the median B-band luminosity decreases by a factor of 0.5 dex. The distribution of galaxy ages obtained by iSEDfit has a large dispersion, but even so, its increment between two epochs corresponds to the Universe age increment indicated by the redshift. According to the models of Lagos et al. (2014), galaxies of properties similar to the BJGs host most of the neutral gas at 0.5 z 1.5. Hence the BJG samples contain tentative targets to sample the neutral gas with submillimeter surveys. ","Citation Text":["van Dokkum et al. (2013)"],"Citation Start End":[[1141,1165]]} {"Identifier":"2019MNRAS.486.4114R__Hartigan_et_al._1995_Instance_1","Paragraph":"We revisit the total (star + circumstellar) mass estimate for the M1701117 system, and the likelihood of it evolving into a brown dwarf. From ALMA continuum observations, the total (dust+gas) mass arising from the circumstellar material in the M1701117 system is 20.98 ± 1.24 MJup. To estimate the intrinsic stellar mass for M1701117, we have used the infrared photometry for this object and the evolutionary models by Baraffe et al. (2003). The J band, in particular, is considered to be least affected by the potential effects of veiling at bluer wavelengths, and circumstellar disc emission further into the infrared (e.g. Hartigan et al. 1995; White & Hillenbrand 2004; Cieza et al. 2005). Fig. 10 shows the UKIDSS (J − K, J) colour–magnitude diagram (cmd). The filled circles represent known members from previous studies in the σ Orionis cluster (Béjar et al. 1999, 2001; Zapatero et al. 2000; Caballero et al. 2007; Caballero 2008). The cluster suffers from negligible reddening (AV ≤ 1 mag; Béjar et al. 1999) and the photometric data has been corrected for the interstellar reddening. M1701117 appears much redder than the main cluster member sequence, which is due to the large K-band excess emission from the circumstellar material. We have overplotted in Fig. 10 the 1, 3, 5, and 8 Myr isochrones from the Baraffe et al. (2003) models. The isochrones at ages of 1 Myr are not provided in these models. The mass scale shown on the right-hand side in Fig. 10 is from the 1 Myr model isochrone at a distance of 410 pc for the cluster. Assuming an age of 1 Myr, we can estimate a stellar mass of ∼40 MJup and a stellar luminosity of 0.012 L$\\odot$ for M1701117. The location of M1701117 to the red of the 1 Myr isochrone in the cmd indicates an age younger than 1 Myr. The typical age of the embedded phase or the age of the protostar formation is considered to be ∼0.01–0.05 Myr, based on the statistics of embedded-to-Class II sources (e.g. Evans et al. 2009). On the other hand, the embedded phase may be shorter for very low-mass protostars and brown dwarfs, as indicated by numerical simulations. The estimates on the stellar mass and luminosity for M1701117 will be lower if the object is younger than 1 Myr.","Citation Text":["Hartigan et al. 1995"],"Citation Start End":[[626,646]]} {"Identifier":"2019MNRAS.486.4114RBéjar_et_al._1999_Instance_1","Paragraph":"We revisit the total (star + circumstellar) mass estimate for the M1701117 system, and the likelihood of it evolving into a brown dwarf. From ALMA continuum observations, the total (dust+gas) mass arising from the circumstellar material in the M1701117 system is 20.98 ± 1.24 MJup. To estimate the intrinsic stellar mass for M1701117, we have used the infrared photometry for this object and the evolutionary models by Baraffe et al. (2003). The J band, in particular, is considered to be least affected by the potential effects of veiling at bluer wavelengths, and circumstellar disc emission further into the infrared (e.g. Hartigan et al. 1995; White & Hillenbrand 2004; Cieza et al. 2005). Fig. 10 shows the UKIDSS (J − K, J) colour–magnitude diagram (cmd). The filled circles represent known members from previous studies in the σ Orionis cluster (Béjar et al. 1999, 2001; Zapatero et al. 2000; Caballero et al. 2007; Caballero 2008). The cluster suffers from negligible reddening (AV ≤ 1 mag; Béjar et al. 1999) and the photometric data has been corrected for the interstellar reddening. M1701117 appears much redder than the main cluster member sequence, which is due to the large K-band excess emission from the circumstellar material. We have overplotted in Fig. 10 the 1, 3, 5, and 8 Myr isochrones from the Baraffe et al. (2003) models. The isochrones at ages of 1 Myr are not provided in these models. The mass scale shown on the right-hand side in Fig. 10 is from the 1 Myr model isochrone at a distance of 410 pc for the cluster. Assuming an age of 1 Myr, we can estimate a stellar mass of ∼40 MJup and a stellar luminosity of 0.012 L$\\odot$ for M1701117. The location of M1701117 to the red of the 1 Myr isochrone in the cmd indicates an age younger than 1 Myr. The typical age of the embedded phase or the age of the protostar formation is considered to be ∼0.01–0.05 Myr, based on the statistics of embedded-to-Class II sources (e.g. Evans et al. 2009). On the other hand, the embedded phase may be shorter for very low-mass protostars and brown dwarfs, as indicated by numerical simulations. The estimates on the stellar mass and luminosity for M1701117 will be lower if the object is younger than 1 Myr.","Citation Text":["Béjar et al. 1999"],"Citation Start End":[[853,870]]} {"Identifier":"2019MNRAS.486.4114RBéjar_et_al._1999_Instance_2","Paragraph":"We revisit the total (star + circumstellar) mass estimate for the M1701117 system, and the likelihood of it evolving into a brown dwarf. From ALMA continuum observations, the total (dust+gas) mass arising from the circumstellar material in the M1701117 system is 20.98 ± 1.24 MJup. To estimate the intrinsic stellar mass for M1701117, we have used the infrared photometry for this object and the evolutionary models by Baraffe et al. (2003). The J band, in particular, is considered to be least affected by the potential effects of veiling at bluer wavelengths, and circumstellar disc emission further into the infrared (e.g. Hartigan et al. 1995; White & Hillenbrand 2004; Cieza et al. 2005). Fig. 10 shows the UKIDSS (J − K, J) colour–magnitude diagram (cmd). The filled circles represent known members from previous studies in the σ Orionis cluster (Béjar et al. 1999, 2001; Zapatero et al. 2000; Caballero et al. 2007; Caballero 2008). The cluster suffers from negligible reddening (AV ≤ 1 mag; Béjar et al. 1999) and the photometric data has been corrected for the interstellar reddening. M1701117 appears much redder than the main cluster member sequence, which is due to the large K-band excess emission from the circumstellar material. We have overplotted in Fig. 10 the 1, 3, 5, and 8 Myr isochrones from the Baraffe et al. (2003) models. The isochrones at ages of 1 Myr are not provided in these models. The mass scale shown on the right-hand side in Fig. 10 is from the 1 Myr model isochrone at a distance of 410 pc for the cluster. Assuming an age of 1 Myr, we can estimate a stellar mass of ∼40 MJup and a stellar luminosity of 0.012 L$\\odot$ for M1701117. The location of M1701117 to the red of the 1 Myr isochrone in the cmd indicates an age younger than 1 Myr. The typical age of the embedded phase or the age of the protostar formation is considered to be ∼0.01–0.05 Myr, based on the statistics of embedded-to-Class II sources (e.g. Evans et al. 2009). On the other hand, the embedded phase may be shorter for very low-mass protostars and brown dwarfs, as indicated by numerical simulations. The estimates on the stellar mass and luminosity for M1701117 will be lower if the object is younger than 1 Myr.","Citation Text":["Béjar et al. 1999"],"Citation Start End":[[999,1016]]} {"Identifier":"2019MNRAS.486.4114RBaraffe_et_al._(2003)___Baraffe_et_al._(2003)_Instance_1","Paragraph":"We revisit the total (star + circumstellar) mass estimate for the M1701117 system, and the likelihood of it evolving into a brown dwarf. From ALMA continuum observations, the total (dust+gas) mass arising from the circumstellar material in the M1701117 system is 20.98 ± 1.24 MJup. To estimate the intrinsic stellar mass for M1701117, we have used the infrared photometry for this object and the evolutionary models by Baraffe et al. (2003). The J band, in particular, is considered to be least affected by the potential effects of veiling at bluer wavelengths, and circumstellar disc emission further into the infrared (e.g. Hartigan et al. 1995; White & Hillenbrand 2004; Cieza et al. 2005). Fig. 10 shows the UKIDSS (J − K, J) colour–magnitude diagram (cmd). The filled circles represent known members from previous studies in the σ Orionis cluster (Béjar et al. 1999, 2001; Zapatero et al. 2000; Caballero et al. 2007; Caballero 2008). The cluster suffers from negligible reddening (AV ≤ 1 mag; Béjar et al. 1999) and the photometric data has been corrected for the interstellar reddening. M1701117 appears much redder than the main cluster member sequence, which is due to the large K-band excess emission from the circumstellar material. We have overplotted in Fig. 10 the 1, 3, 5, and 8 Myr isochrones from the Baraffe et al. (2003) models. The isochrones at ages of 1 Myr are not provided in these models. The mass scale shown on the right-hand side in Fig. 10 is from the 1 Myr model isochrone at a distance of 410 pc for the cluster. Assuming an age of 1 Myr, we can estimate a stellar mass of ∼40 MJup and a stellar luminosity of 0.012 L$\\odot$ for M1701117. The location of M1701117 to the red of the 1 Myr isochrone in the cmd indicates an age younger than 1 Myr. The typical age of the embedded phase or the age of the protostar formation is considered to be ∼0.01–0.05 Myr, based on the statistics of embedded-to-Class II sources (e.g. Evans et al. 2009). On the other hand, the embedded phase may be shorter for very low-mass protostars and brown dwarfs, as indicated by numerical simulations. The estimates on the stellar mass and luminosity for M1701117 will be lower if the object is younger than 1 Myr.","Citation Text":["Baraffe et al. (2003)","Baraffe et al. (2003)"],"Citation Start End":[[1318,1339],[419,440]]} {"Identifier":"2019MNRAS.486.4114REvans_et_al._2009_Instance_1","Paragraph":"We revisit the total (star + circumstellar) mass estimate for the M1701117 system, and the likelihood of it evolving into a brown dwarf. From ALMA continuum observations, the total (dust+gas) mass arising from the circumstellar material in the M1701117 system is 20.98 ± 1.24 MJup. To estimate the intrinsic stellar mass for M1701117, we have used the infrared photometry for this object and the evolutionary models by Baraffe et al. (2003). The J band, in particular, is considered to be least affected by the potential effects of veiling at bluer wavelengths, and circumstellar disc emission further into the infrared (e.g. Hartigan et al. 1995; White & Hillenbrand 2004; Cieza et al. 2005). Fig. 10 shows the UKIDSS (J − K, J) colour–magnitude diagram (cmd). The filled circles represent known members from previous studies in the σ Orionis cluster (Béjar et al. 1999, 2001; Zapatero et al. 2000; Caballero et al. 2007; Caballero 2008). The cluster suffers from negligible reddening (AV ≤ 1 mag; Béjar et al. 1999) and the photometric data has been corrected for the interstellar reddening. M1701117 appears much redder than the main cluster member sequence, which is due to the large K-band excess emission from the circumstellar material. We have overplotted in Fig. 10 the 1, 3, 5, and 8 Myr isochrones from the Baraffe et al. (2003) models. The isochrones at ages of 1 Myr are not provided in these models. The mass scale shown on the right-hand side in Fig. 10 is from the 1 Myr model isochrone at a distance of 410 pc for the cluster. Assuming an age of 1 Myr, we can estimate a stellar mass of ∼40 MJup and a stellar luminosity of 0.012 L$\\odot$ for M1701117. The location of M1701117 to the red of the 1 Myr isochrone in the cmd indicates an age younger than 1 Myr. The typical age of the embedded phase or the age of the protostar formation is considered to be ∼0.01–0.05 Myr, based on the statistics of embedded-to-Class II sources (e.g. Evans et al. 2009). On the other hand, the embedded phase may be shorter for very low-mass protostars and brown dwarfs, as indicated by numerical simulations. The estimates on the stellar mass and luminosity for M1701117 will be lower if the object is younger than 1 Myr.","Citation Text":["Evans et al. 2009"],"Citation Start End":[[1951,1968]]} {"Identifier":"2020MNRAS.497.5344E__Renzo_et_al._2019b_Instance_1","Paragraph":"For MS high-velocity stars seemingly ejected from the Galactic disc, on the other hand, two main processes are typically blamed. In the dynamical ejection scenario (DES; e.g. Poveda, Ruiz & Allen 1967; Leonard & Duncan 1990; Leonard 1991; Perets & Šubr 2012; Oh & Kroupa 2016), exchange encounters in dense stellar systems (Aarseth 1974) may eject stars at high velocities. In the binary supernova scenario (BSS; e.g. Blaauw 1961; Boersma 1961; Tauris & Takens 1998; Portegies Zwart 2000; Tauris 2015; Renzo et al. 2019b), the massive primary in a binary system explodes in a core-collapse (CC) supernova, disrupting the binary and ejecting its MS companion with a velocity comparable to its pre-CC orbital velocity. Both processes are known to occur in the Milky Way (Hoogerwerf, de Bruijne & de Zeeuw 2001; Jilinski et al. 2010) and are generally thought to be responsible for the known sample of ‘runaway stars’ with ejection velocities of ${\\ge}30\\!-\\!40\\, \\mathrm{km\\ s^{-1}}$ (Blaauw 1961), though their relative contribution is not yet well constrained (see Hoogerwerf et al. 2001; Renzo et al. 2019b). With characteristic ejection speeds of the order of a few tens of km s−1, it is not yet known whether these mechanisms can eject stars of the order of hundreds of km s−1 with sufficient frequency to explain the current known sample of ‘hyper-runaway stars’ (HRSs) – runaway stars ejected near to or above the Galactic escape velocity at their location. While ejection velocities in the neighbourhood of ∼1000 km s−1 are possible in both the DES (Leonard 1991) and BSS (e.g. Tauris & Takens 1998; Tauris 2015) scenarios, these situations are thought to be rare. Recent N-body simulations of young star clusters have found that ejections in excess of 200 km s−1 are very rare (Perets & Šubr 2012; Oh & Kroupa 2016). Binary population synthesis models simulating a large number of binary systems show that ejections above 200 km s−1 are vastly outnumbered by ejections of the order of ∼10 km s−1 (Portegies Zwart 2000; Eldridge, Langer & Tout 2011; Renzo et al. 2019b).","Citation Text":["Renzo et al. 2019b"],"Citation Start End":[[502,520]]} {"Identifier":"2020MNRAS.497.5344E__Renzo_et_al._2019b_Instance_2","Paragraph":"For MS high-velocity stars seemingly ejected from the Galactic disc, on the other hand, two main processes are typically blamed. In the dynamical ejection scenario (DES; e.g. Poveda, Ruiz & Allen 1967; Leonard & Duncan 1990; Leonard 1991; Perets & Šubr 2012; Oh & Kroupa 2016), exchange encounters in dense stellar systems (Aarseth 1974) may eject stars at high velocities. In the binary supernova scenario (BSS; e.g. Blaauw 1961; Boersma 1961; Tauris & Takens 1998; Portegies Zwart 2000; Tauris 2015; Renzo et al. 2019b), the massive primary in a binary system explodes in a core-collapse (CC) supernova, disrupting the binary and ejecting its MS companion with a velocity comparable to its pre-CC orbital velocity. Both processes are known to occur in the Milky Way (Hoogerwerf, de Bruijne & de Zeeuw 2001; Jilinski et al. 2010) and are generally thought to be responsible for the known sample of ‘runaway stars’ with ejection velocities of ${\\ge}30\\!-\\!40\\, \\mathrm{km\\ s^{-1}}$ (Blaauw 1961), though their relative contribution is not yet well constrained (see Hoogerwerf et al. 2001; Renzo et al. 2019b). With characteristic ejection speeds of the order of a few tens of km s−1, it is not yet known whether these mechanisms can eject stars of the order of hundreds of km s−1 with sufficient frequency to explain the current known sample of ‘hyper-runaway stars’ (HRSs) – runaway stars ejected near to or above the Galactic escape velocity at their location. While ejection velocities in the neighbourhood of ∼1000 km s−1 are possible in both the DES (Leonard 1991) and BSS (e.g. Tauris & Takens 1998; Tauris 2015) scenarios, these situations are thought to be rare. Recent N-body simulations of young star clusters have found that ejections in excess of 200 km s−1 are very rare (Perets & Šubr 2012; Oh & Kroupa 2016). Binary population synthesis models simulating a large number of binary systems show that ejections above 200 km s−1 are vastly outnumbered by ejections of the order of ∼10 km s−1 (Portegies Zwart 2000; Eldridge, Langer & Tout 2011; Renzo et al. 2019b).","Citation Text":["Renzo et al. 2019b"],"Citation Start End":[[1089,1107]]} {"Identifier":"2020MNRAS.497.5344E__Renzo_et_al._2019b_Instance_3","Paragraph":"For MS high-velocity stars seemingly ejected from the Galactic disc, on the other hand, two main processes are typically blamed. In the dynamical ejection scenario (DES; e.g. Poveda, Ruiz & Allen 1967; Leonard & Duncan 1990; Leonard 1991; Perets & Šubr 2012; Oh & Kroupa 2016), exchange encounters in dense stellar systems (Aarseth 1974) may eject stars at high velocities. In the binary supernova scenario (BSS; e.g. Blaauw 1961; Boersma 1961; Tauris & Takens 1998; Portegies Zwart 2000; Tauris 2015; Renzo et al. 2019b), the massive primary in a binary system explodes in a core-collapse (CC) supernova, disrupting the binary and ejecting its MS companion with a velocity comparable to its pre-CC orbital velocity. Both processes are known to occur in the Milky Way (Hoogerwerf, de Bruijne & de Zeeuw 2001; Jilinski et al. 2010) and are generally thought to be responsible for the known sample of ‘runaway stars’ with ejection velocities of ${\\ge}30\\!-\\!40\\, \\mathrm{km\\ s^{-1}}$ (Blaauw 1961), though their relative contribution is not yet well constrained (see Hoogerwerf et al. 2001; Renzo et al. 2019b). With characteristic ejection speeds of the order of a few tens of km s−1, it is not yet known whether these mechanisms can eject stars of the order of hundreds of km s−1 with sufficient frequency to explain the current known sample of ‘hyper-runaway stars’ (HRSs) – runaway stars ejected near to or above the Galactic escape velocity at their location. While ejection velocities in the neighbourhood of ∼1000 km s−1 are possible in both the DES (Leonard 1991) and BSS (e.g. Tauris & Takens 1998; Tauris 2015) scenarios, these situations are thought to be rare. Recent N-body simulations of young star clusters have found that ejections in excess of 200 km s−1 are very rare (Perets & Šubr 2012; Oh & Kroupa 2016). Binary population synthesis models simulating a large number of binary systems show that ejections above 200 km s−1 are vastly outnumbered by ejections of the order of ∼10 km s−1 (Portegies Zwart 2000; Eldridge, Langer & Tout 2011; Renzo et al. 2019b).","Citation Text":["Renzo et al. 2019b"],"Citation Start End":[[2056,2074]]} {"Identifier":"2021MNRAS.503.2108P__Pan_et_al._2020_Instance_1","Paragraph":"CCSNe are also of interest for GW astronomy as targets in their own right. As the sensitivity of GW detectors increases, they will begin to detect not only binary mergers but also other lower amplitude sources of GWs such as CCSNe. Accurate knowledge of the GW emission from CCSNe will be essential for detection and parameter estimation. The GW signal from rotational core bounce has already been well covered in the literature (e.g. Dimmelmeier et al. 2008; Abdikamalov et al. 2014; Fuller et al. 2015; Richers et al. 2017). In the non-rotating case, the GW emission from the post-bounce phase has been studied using self-consistent 3D simulations by many groups (Kuroda, Kotake & Takiwaki 2016; Andresen et al. 2017, 2019; Kuroda et al. 2017, 2018; Powell & Müller 2019, 2020; Radice et al. 2019; Andresen, Glas & Janka 2020; Mezzacappa et al. 2020; Pan et al. 2020). The structure of the GW emission has shown common features in different simulations from recent years. The dominant emission feature in the GW emission is due to the quadrupolar surface f\/g mode 1 of the proto-neutron star (PNS), which produces GW frequencies rising in time from a few hundred Hz up to a few kHz (Müller, Janka & Wongwathanarat 2012; Sotani et al. 2017; Kuroda et al. 2018; Morozova et al. 2018; Torres-Forné et al. 2018, 2019). In addition, some models (Kuroda et al. 2016, 2017; Andresen et al. 2017; Mezzacappa et al. 2020; Powell & Müller 2020) exhibit low-frequency GW emission due to the standing accretion shock instability (SASI; Blondin, Mezzacappa & DeMarino 2003; Blondin & Mezzacappa 2006; Foglizzo et al. 2007). In rapidly rotating models, very strong GW emission can also occur during the post-bounce phase due to a corotation instability (Takiwaki & Kotake 2018). The emerging understanding of the GW emission features has led to the formulation of universal relations for the GW emission (Torres-Forné et al. 2019) and paved the way for phenomenological modelling for CCSN signals (Astone et al. 2018). Further work is still needed, however, to extend these models to fully explore CCSN GW signals from across the progenitor parameter space. The majority of 3D simulations that include GW emission are for progenitor stars below $30\\, \\mathrm{M}_{\\odot }$. In this paper, we perform simulations of high-mass Population III (Pop-III) stars in the pulsational pair instability regime to expand the parameter space coverage of 3D simulations and to provide further insights into the massive and very massive star remnant BH population.","Citation Text":["Pan et al. 2020"],"Citation Start End":[[853,868]]} {"Identifier":"2021MNRAS.503.2108PAbdikamalov_et_al._2014_Instance_1","Paragraph":"CCSNe are also of interest for GW astronomy as targets in their own right. As the sensitivity of GW detectors increases, they will begin to detect not only binary mergers but also other lower amplitude sources of GWs such as CCSNe. Accurate knowledge of the GW emission from CCSNe will be essential for detection and parameter estimation. The GW signal from rotational core bounce has already been well covered in the literature (e.g. Dimmelmeier et al. 2008; Abdikamalov et al. 2014; Fuller et al. 2015; Richers et al. 2017). In the non-rotating case, the GW emission from the post-bounce phase has been studied using self-consistent 3D simulations by many groups (Kuroda, Kotake & Takiwaki 2016; Andresen et al. 2017, 2019; Kuroda et al. 2017, 2018; Powell & Müller 2019, 2020; Radice et al. 2019; Andresen, Glas & Janka 2020; Mezzacappa et al. 2020; Pan et al. 2020). The structure of the GW emission has shown common features in different simulations from recent years. The dominant emission feature in the GW emission is due to the quadrupolar surface f\/g mode 1 of the proto-neutron star (PNS), which produces GW frequencies rising in time from a few hundred Hz up to a few kHz (Müller, Janka & Wongwathanarat 2012; Sotani et al. 2017; Kuroda et al. 2018; Morozova et al. 2018; Torres-Forné et al. 2018, 2019). In addition, some models (Kuroda et al. 2016, 2017; Andresen et al. 2017; Mezzacappa et al. 2020; Powell & Müller 2020) exhibit low-frequency GW emission due to the standing accretion shock instability (SASI; Blondin, Mezzacappa & DeMarino 2003; Blondin & Mezzacappa 2006; Foglizzo et al. 2007). In rapidly rotating models, very strong GW emission can also occur during the post-bounce phase due to a corotation instability (Takiwaki & Kotake 2018). The emerging understanding of the GW emission features has led to the formulation of universal relations for the GW emission (Torres-Forné et al. 2019) and paved the way for phenomenological modelling for CCSN signals (Astone et al. 2018). Further work is still needed, however, to extend these models to fully explore CCSN GW signals from across the progenitor parameter space. The majority of 3D simulations that include GW emission are for progenitor stars below $30\\, \\mathrm{M}_{\\odot }$. In this paper, we perform simulations of high-mass Population III (Pop-III) stars in the pulsational pair instability regime to expand the parameter space coverage of 3D simulations and to provide further insights into the massive and very massive star remnant BH population.","Citation Text":["Abdikamalov et al. 2014"],"Citation Start End":[[460,483]]} {"Identifier":"2021MNRAS.503.2108PMüller,_Janka_&_Wongwathanarat_2012_Instance_1","Paragraph":"CCSNe are also of interest for GW astronomy as targets in their own right. As the sensitivity of GW detectors increases, they will begin to detect not only binary mergers but also other lower amplitude sources of GWs such as CCSNe. Accurate knowledge of the GW emission from CCSNe will be essential for detection and parameter estimation. The GW signal from rotational core bounce has already been well covered in the literature (e.g. Dimmelmeier et al. 2008; Abdikamalov et al. 2014; Fuller et al. 2015; Richers et al. 2017). In the non-rotating case, the GW emission from the post-bounce phase has been studied using self-consistent 3D simulations by many groups (Kuroda, Kotake & Takiwaki 2016; Andresen et al. 2017, 2019; Kuroda et al. 2017, 2018; Powell & Müller 2019, 2020; Radice et al. 2019; Andresen, Glas & Janka 2020; Mezzacappa et al. 2020; Pan et al. 2020). The structure of the GW emission has shown common features in different simulations from recent years. The dominant emission feature in the GW emission is due to the quadrupolar surface f\/g mode 1 of the proto-neutron star (PNS), which produces GW frequencies rising in time from a few hundred Hz up to a few kHz (Müller, Janka & Wongwathanarat 2012; Sotani et al. 2017; Kuroda et al. 2018; Morozova et al. 2018; Torres-Forné et al. 2018, 2019). In addition, some models (Kuroda et al. 2016, 2017; Andresen et al. 2017; Mezzacappa et al. 2020; Powell & Müller 2020) exhibit low-frequency GW emission due to the standing accretion shock instability (SASI; Blondin, Mezzacappa & DeMarino 2003; Blondin & Mezzacappa 2006; Foglizzo et al. 2007). In rapidly rotating models, very strong GW emission can also occur during the post-bounce phase due to a corotation instability (Takiwaki & Kotake 2018). The emerging understanding of the GW emission features has led to the formulation of universal relations for the GW emission (Torres-Forné et al. 2019) and paved the way for phenomenological modelling for CCSN signals (Astone et al. 2018). Further work is still needed, however, to extend these models to fully explore CCSN GW signals from across the progenitor parameter space. The majority of 3D simulations that include GW emission are for progenitor stars below $30\\, \\mathrm{M}_{\\odot }$. In this paper, we perform simulations of high-mass Population III (Pop-III) stars in the pulsational pair instability regime to expand the parameter space coverage of 3D simulations and to provide further insights into the massive and very massive star remnant BH population.","Citation Text":["Müller, Janka & Wongwathanarat 2012"],"Citation Start End":[[1185,1220]]} {"Identifier":"2021MNRAS.503.2108PTakiwaki_&_Kotake_2018_Instance_1","Paragraph":"CCSNe are also of interest for GW astronomy as targets in their own right. As the sensitivity of GW detectors increases, they will begin to detect not only binary mergers but also other lower amplitude sources of GWs such as CCSNe. Accurate knowledge of the GW emission from CCSNe will be essential for detection and parameter estimation. The GW signal from rotational core bounce has already been well covered in the literature (e.g. Dimmelmeier et al. 2008; Abdikamalov et al. 2014; Fuller et al. 2015; Richers et al. 2017). In the non-rotating case, the GW emission from the post-bounce phase has been studied using self-consistent 3D simulations by many groups (Kuroda, Kotake & Takiwaki 2016; Andresen et al. 2017, 2019; Kuroda et al. 2017, 2018; Powell & Müller 2019, 2020; Radice et al. 2019; Andresen, Glas & Janka 2020; Mezzacappa et al. 2020; Pan et al. 2020). The structure of the GW emission has shown common features in different simulations from recent years. The dominant emission feature in the GW emission is due to the quadrupolar surface f\/g mode 1 of the proto-neutron star (PNS), which produces GW frequencies rising in time from a few hundred Hz up to a few kHz (Müller, Janka & Wongwathanarat 2012; Sotani et al. 2017; Kuroda et al. 2018; Morozova et al. 2018; Torres-Forné et al. 2018, 2019). In addition, some models (Kuroda et al. 2016, 2017; Andresen et al. 2017; Mezzacappa et al. 2020; Powell & Müller 2020) exhibit low-frequency GW emission due to the standing accretion shock instability (SASI; Blondin, Mezzacappa & DeMarino 2003; Blondin & Mezzacappa 2006; Foglizzo et al. 2007). In rapidly rotating models, very strong GW emission can also occur during the post-bounce phase due to a corotation instability (Takiwaki & Kotake 2018). The emerging understanding of the GW emission features has led to the formulation of universal relations for the GW emission (Torres-Forné et al. 2019) and paved the way for phenomenological modelling for CCSN signals (Astone et al. 2018). Further work is still needed, however, to extend these models to fully explore CCSN GW signals from across the progenitor parameter space. The majority of 3D simulations that include GW emission are for progenitor stars below $30\\, \\mathrm{M}_{\\odot }$. In this paper, we perform simulations of high-mass Population III (Pop-III) stars in the pulsational pair instability regime to expand the parameter space coverage of 3D simulations and to provide further insights into the massive and very massive star remnant BH population.","Citation Text":["Takiwaki & Kotake 2018"],"Citation Start End":[[1742,1764]]} {"Identifier":"2021MNRAS.503.2108PAstone_et_al._2018_Instance_1","Paragraph":"CCSNe are also of interest for GW astronomy as targets in their own right. As the sensitivity of GW detectors increases, they will begin to detect not only binary mergers but also other lower amplitude sources of GWs such as CCSNe. Accurate knowledge of the GW emission from CCSNe will be essential for detection and parameter estimation. The GW signal from rotational core bounce has already been well covered in the literature (e.g. Dimmelmeier et al. 2008; Abdikamalov et al. 2014; Fuller et al. 2015; Richers et al. 2017). In the non-rotating case, the GW emission from the post-bounce phase has been studied using self-consistent 3D simulations by many groups (Kuroda, Kotake & Takiwaki 2016; Andresen et al. 2017, 2019; Kuroda et al. 2017, 2018; Powell & Müller 2019, 2020; Radice et al. 2019; Andresen, Glas & Janka 2020; Mezzacappa et al. 2020; Pan et al. 2020). The structure of the GW emission has shown common features in different simulations from recent years. The dominant emission feature in the GW emission is due to the quadrupolar surface f\/g mode 1 of the proto-neutron star (PNS), which produces GW frequencies rising in time from a few hundred Hz up to a few kHz (Müller, Janka & Wongwathanarat 2012; Sotani et al. 2017; Kuroda et al. 2018; Morozova et al. 2018; Torres-Forné et al. 2018, 2019). In addition, some models (Kuroda et al. 2016, 2017; Andresen et al. 2017; Mezzacappa et al. 2020; Powell & Müller 2020) exhibit low-frequency GW emission due to the standing accretion shock instability (SASI; Blondin, Mezzacappa & DeMarino 2003; Blondin & Mezzacappa 2006; Foglizzo et al. 2007). In rapidly rotating models, very strong GW emission can also occur during the post-bounce phase due to a corotation instability (Takiwaki & Kotake 2018). The emerging understanding of the GW emission features has led to the formulation of universal relations for the GW emission (Torres-Forné et al. 2019) and paved the way for phenomenological modelling for CCSN signals (Astone et al. 2018). Further work is still needed, however, to extend these models to fully explore CCSN GW signals from across the progenitor parameter space. The majority of 3D simulations that include GW emission are for progenitor stars below $30\\, \\mathrm{M}_{\\odot }$. In this paper, we perform simulations of high-mass Population III (Pop-III) stars in the pulsational pair instability regime to expand the parameter space coverage of 3D simulations and to provide further insights into the massive and very massive star remnant BH population.","Citation Text":["Astone et al. 2018"],"Citation Start End":[[1986,2004]]} {"Identifier":"2020AandA...644A..64D__Lee_et_al._(2012)_Instance_1","Paragraph":"Several faint and sparse knots are detected over all the field of observations, especially around the systemic velocity of IC443 vLSR = −4.5 km s−1 (Hewitt et al. 2006). These structures, noticeable between v = −7.5 km s−1 and v = −1.5 km s−1, might either correspond to a slice of turbulent medium driven by the SN shockwave and\/or belong to the ambient gas associated with the NW-SE molecular cloud in which IC443G is embedded (Lee et al. 2012). Other than that, the description of the region probed by our observations can be divided into the following six distinct structures:\n\n1.Cloudlet: in the upper part of the field we observe a large (~ 5′ × 2′, i.e., ~ 2.8 × 1.1 pc) elongated cloudlet detected between v = −7.0 km s−1 and v = −5.5 km s−1 (indicated by the letter “A” in Fig. 2), which is also detected in 12CO(3–2). This structure was labeled G1 by Zhang et al. (2010), as part of the double-peaked morphology of the extended G region. The 13CO J = 1–0 counterpart of this structure is much brighter than the other main structures in the field, and it is also detected in the transitions J = 2–1 and J = 3–2, and in C18O J = 1–0 and J = 2–1. This structure was also presented and characterized by Lee et al. (2012) who proposed the label SC 03, among a total of 12 SCs (of size ~1′) found in IC443.\n2.Ring-like structure: a ring-like structure seemingly lying in the center of the field (indicated by the letter “B” in Fig. 2), appearing between v = −5.5 km s−1 and v = −4.5 km s−1 and also detected in 12CO(3–2). It has a semimajor axis of 1.5′, or 0.8 pc. This structure might be spurious and is likely to be physically connected to the elongated cloudlet as both are spatially contiguous and their emission lines are spectrally close. It is partially detected as well in our observations of 13CO J = 1–0, J = 2–1 and J = 3–2, and also has a faint, partial counterpart in C18O J = 1–0 and J = 2–1. To understand the nature of this region we searched for counterparts in Spitzer Multiband Imaging Photometer (MIPS), WISE, DSS and XMM-Newton data; and in near-infrared and optical point source catalogs (Sect. 5), without success. Owing to projection effects, this apparent circular shape could also be explained by an unresolved and clumpy distribution of gas.\n3.Shocked clump: in the lower part of the field we identify a very bright clump emitting between v = −31.0 km s−1 and v = 16 km s−1. This structure of size ~2′ × 0.75′ (~ 1.1 × 0.4 pc), which is detected in the 12CO(3–2) transition as well, belongs to the southwestern ridge of the molecular shell of the SNR and has been described as a shocked molecular structure by several studies (van Dishoeck et al. 1993; Cesarsky et al. 1999; Snell et al. 2005; Shinn et al. 2011; Zhang et al. 2010). The core of the shocked clump (indicated by the letter “C” in Fig. 2) is also detected in 13CO in the transitions J = 1–0, J = 2–1, and J = 3–2, and in C18O J = 1–0 and J = 2–1.\n4.Shocked knot: an additional shocked knot (indicated by the letter “D” in Fig. 2) is also detected to the west of the previously described structure. This fainter and smaller structure is spatially separated from the main shocked clump.\n5.At the same position as the shocked clump and extending southward and westward, we find a faint, elongated clump emitting between v = 5.0 km s−1 and v = 7.5 km s−1. This structure (indicated by the symbol “*” in Fig. 2) spatially coincides with the shocked clump, yet the peak velocity is not exactly the same (see developments on kinematics of the region in Sect. 3.3). It has a faint counterpart in 13CO(1–0). Observations of the ambient molecular cloud by Lee et al. (2012) indicate this structure as part of a faint NE-SW complex of molecular gas in the velocity range +3 km s−1 vLSR +10 km s−1.\n6.Finally, the 13CO(1–0) map (Fig. 4, right panel and Fig. D.2) indicates a large clump of gas extending from the bottom center to the right end of the field, with a bright knot in the bottom right corner of the field. However, this structure has no bright, well-defined counterpart in any of the 12CO transitions maps. It is spatially and kinematically correlated with the faint and diffuse 12CO J = 1–0 and J = 2–1 emission seen in the velocity range −5.5 km s−1 vLSR −2 km s−1. From the comparison with the 12CO observations of Lee et al. (2012) and 13CO observations of Su et al. (2014) toward the SNR, we conclude that this structure is part of the western molecular complex observed in the velocity range −10 km s−1 vLSR 0 km s−1.\n","Citation Text":["Lee et al. 2012"],"Citation Start End":[[430,445]]} {"Identifier":"2020AandA...644A..64D__Lee_et_al._(2012)_Instance_2","Paragraph":"Several faint and sparse knots are detected over all the field of observations, especially around the systemic velocity of IC443 vLSR = −4.5 km s−1 (Hewitt et al. 2006). These structures, noticeable between v = −7.5 km s−1 and v = −1.5 km s−1, might either correspond to a slice of turbulent medium driven by the SN shockwave and\/or belong to the ambient gas associated with the NW-SE molecular cloud in which IC443G is embedded (Lee et al. 2012). Other than that, the description of the region probed by our observations can be divided into the following six distinct structures:\n\n1.Cloudlet: in the upper part of the field we observe a large (~ 5′ × 2′, i.e., ~ 2.8 × 1.1 pc) elongated cloudlet detected between v = −7.0 km s−1 and v = −5.5 km s−1 (indicated by the letter “A” in Fig. 2), which is also detected in 12CO(3–2). This structure was labeled G1 by Zhang et al. (2010), as part of the double-peaked morphology of the extended G region. The 13CO J = 1–0 counterpart of this structure is much brighter than the other main structures in the field, and it is also detected in the transitions J = 2–1 and J = 3–2, and in C18O J = 1–0 and J = 2–1. This structure was also presented and characterized by Lee et al. (2012) who proposed the label SC 03, among a total of 12 SCs (of size ~1′) found in IC443.\n2.Ring-like structure: a ring-like structure seemingly lying in the center of the field (indicated by the letter “B” in Fig. 2), appearing between v = −5.5 km s−1 and v = −4.5 km s−1 and also detected in 12CO(3–2). It has a semimajor axis of 1.5′, or 0.8 pc. This structure might be spurious and is likely to be physically connected to the elongated cloudlet as both are spatially contiguous and their emission lines are spectrally close. It is partially detected as well in our observations of 13CO J = 1–0, J = 2–1 and J = 3–2, and also has a faint, partial counterpart in C18O J = 1–0 and J = 2–1. To understand the nature of this region we searched for counterparts in Spitzer Multiband Imaging Photometer (MIPS), WISE, DSS and XMM-Newton data; and in near-infrared and optical point source catalogs (Sect. 5), without success. Owing to projection effects, this apparent circular shape could also be explained by an unresolved and clumpy distribution of gas.\n3.Shocked clump: in the lower part of the field we identify a very bright clump emitting between v = −31.0 km s−1 and v = 16 km s−1. This structure of size ~2′ × 0.75′ (~ 1.1 × 0.4 pc), which is detected in the 12CO(3–2) transition as well, belongs to the southwestern ridge of the molecular shell of the SNR and has been described as a shocked molecular structure by several studies (van Dishoeck et al. 1993; Cesarsky et al. 1999; Snell et al. 2005; Shinn et al. 2011; Zhang et al. 2010). The core of the shocked clump (indicated by the letter “C” in Fig. 2) is also detected in 13CO in the transitions J = 1–0, J = 2–1, and J = 3–2, and in C18O J = 1–0 and J = 2–1.\n4.Shocked knot: an additional shocked knot (indicated by the letter “D” in Fig. 2) is also detected to the west of the previously described structure. This fainter and smaller structure is spatially separated from the main shocked clump.\n5.At the same position as the shocked clump and extending southward and westward, we find a faint, elongated clump emitting between v = 5.0 km s−1 and v = 7.5 km s−1. This structure (indicated by the symbol “*” in Fig. 2) spatially coincides with the shocked clump, yet the peak velocity is not exactly the same (see developments on kinematics of the region in Sect. 3.3). It has a faint counterpart in 13CO(1–0). Observations of the ambient molecular cloud by Lee et al. (2012) indicate this structure as part of a faint NE-SW complex of molecular gas in the velocity range +3 km s−1 vLSR +10 km s−1.\n6.Finally, the 13CO(1–0) map (Fig. 4, right panel and Fig. D.2) indicates a large clump of gas extending from the bottom center to the right end of the field, with a bright knot in the bottom right corner of the field. However, this structure has no bright, well-defined counterpart in any of the 12CO transitions maps. It is spatially and kinematically correlated with the faint and diffuse 12CO J = 1–0 and J = 2–1 emission seen in the velocity range −5.5 km s−1 vLSR −2 km s−1. From the comparison with the 12CO observations of Lee et al. (2012) and 13CO observations of Su et al. (2014) toward the SNR, we conclude that this structure is part of the western molecular complex observed in the velocity range −10 km s−1 vLSR 0 km s−1.\n","Citation Text":["Lee et al. (2012)"],"Citation Start End":[[1209,1226]]} {"Identifier":"2020AandA...644A..64D__Lee_et_al._(2012)_Instance_3","Paragraph":"Several faint and sparse knots are detected over all the field of observations, especially around the systemic velocity of IC443 vLSR = −4.5 km s−1 (Hewitt et al. 2006). These structures, noticeable between v = −7.5 km s−1 and v = −1.5 km s−1, might either correspond to a slice of turbulent medium driven by the SN shockwave and\/or belong to the ambient gas associated with the NW-SE molecular cloud in which IC443G is embedded (Lee et al. 2012). Other than that, the description of the region probed by our observations can be divided into the following six distinct structures:\n\n1.Cloudlet: in the upper part of the field we observe a large (~ 5′ × 2′, i.e., ~ 2.8 × 1.1 pc) elongated cloudlet detected between v = −7.0 km s−1 and v = −5.5 km s−1 (indicated by the letter “A” in Fig. 2), which is also detected in 12CO(3–2). This structure was labeled G1 by Zhang et al. (2010), as part of the double-peaked morphology of the extended G region. The 13CO J = 1–0 counterpart of this structure is much brighter than the other main structures in the field, and it is also detected in the transitions J = 2–1 and J = 3–2, and in C18O J = 1–0 and J = 2–1. This structure was also presented and characterized by Lee et al. (2012) who proposed the label SC 03, among a total of 12 SCs (of size ~1′) found in IC443.\n2.Ring-like structure: a ring-like structure seemingly lying in the center of the field (indicated by the letter “B” in Fig. 2), appearing between v = −5.5 km s−1 and v = −4.5 km s−1 and also detected in 12CO(3–2). It has a semimajor axis of 1.5′, or 0.8 pc. This structure might be spurious and is likely to be physically connected to the elongated cloudlet as both are spatially contiguous and their emission lines are spectrally close. It is partially detected as well in our observations of 13CO J = 1–0, J = 2–1 and J = 3–2, and also has a faint, partial counterpart in C18O J = 1–0 and J = 2–1. To understand the nature of this region we searched for counterparts in Spitzer Multiband Imaging Photometer (MIPS), WISE, DSS and XMM-Newton data; and in near-infrared and optical point source catalogs (Sect. 5), without success. Owing to projection effects, this apparent circular shape could also be explained by an unresolved and clumpy distribution of gas.\n3.Shocked clump: in the lower part of the field we identify a very bright clump emitting between v = −31.0 km s−1 and v = 16 km s−1. This structure of size ~2′ × 0.75′ (~ 1.1 × 0.4 pc), which is detected in the 12CO(3–2) transition as well, belongs to the southwestern ridge of the molecular shell of the SNR and has been described as a shocked molecular structure by several studies (van Dishoeck et al. 1993; Cesarsky et al. 1999; Snell et al. 2005; Shinn et al. 2011; Zhang et al. 2010). The core of the shocked clump (indicated by the letter “C” in Fig. 2) is also detected in 13CO in the transitions J = 1–0, J = 2–1, and J = 3–2, and in C18O J = 1–0 and J = 2–1.\n4.Shocked knot: an additional shocked knot (indicated by the letter “D” in Fig. 2) is also detected to the west of the previously described structure. This fainter and smaller structure is spatially separated from the main shocked clump.\n5.At the same position as the shocked clump and extending southward and westward, we find a faint, elongated clump emitting between v = 5.0 km s−1 and v = 7.5 km s−1. This structure (indicated by the symbol “*” in Fig. 2) spatially coincides with the shocked clump, yet the peak velocity is not exactly the same (see developments on kinematics of the region in Sect. 3.3). It has a faint counterpart in 13CO(1–0). Observations of the ambient molecular cloud by Lee et al. (2012) indicate this structure as part of a faint NE-SW complex of molecular gas in the velocity range +3 km s−1 vLSR +10 km s−1.\n6.Finally, the 13CO(1–0) map (Fig. 4, right panel and Fig. D.2) indicates a large clump of gas extending from the bottom center to the right end of the field, with a bright knot in the bottom right corner of the field. However, this structure has no bright, well-defined counterpart in any of the 12CO transitions maps. It is spatially and kinematically correlated with the faint and diffuse 12CO J = 1–0 and J = 2–1 emission seen in the velocity range −5.5 km s−1 vLSR −2 km s−1. From the comparison with the 12CO observations of Lee et al. (2012) and 13CO observations of Su et al. (2014) toward the SNR, we conclude that this structure is part of the western molecular complex observed in the velocity range −10 km s−1 vLSR 0 km s−1.\n","Citation Text":["Lee et al. (2012)"],"Citation Start End":[[3642,3659]]} {"Identifier":"2020AandA...644A..64D__Lee_et_al._(2012)_Instance_4","Paragraph":"Several faint and sparse knots are detected over all the field of observations, especially around the systemic velocity of IC443 vLSR = −4.5 km s−1 (Hewitt et al. 2006). These structures, noticeable between v = −7.5 km s−1 and v = −1.5 km s−1, might either correspond to a slice of turbulent medium driven by the SN shockwave and\/or belong to the ambient gas associated with the NW-SE molecular cloud in which IC443G is embedded (Lee et al. 2012). Other than that, the description of the region probed by our observations can be divided into the following six distinct structures:\n\n1.Cloudlet: in the upper part of the field we observe a large (~ 5′ × 2′, i.e., ~ 2.8 × 1.1 pc) elongated cloudlet detected between v = −7.0 km s−1 and v = −5.5 km s−1 (indicated by the letter “A” in Fig. 2), which is also detected in 12CO(3–2). This structure was labeled G1 by Zhang et al. (2010), as part of the double-peaked morphology of the extended G region. The 13CO J = 1–0 counterpart of this structure is much brighter than the other main structures in the field, and it is also detected in the transitions J = 2–1 and J = 3–2, and in C18O J = 1–0 and J = 2–1. This structure was also presented and characterized by Lee et al. (2012) who proposed the label SC 03, among a total of 12 SCs (of size ~1′) found in IC443.\n2.Ring-like structure: a ring-like structure seemingly lying in the center of the field (indicated by the letter “B” in Fig. 2), appearing between v = −5.5 km s−1 and v = −4.5 km s−1 and also detected in 12CO(3–2). It has a semimajor axis of 1.5′, or 0.8 pc. This structure might be spurious and is likely to be physically connected to the elongated cloudlet as both are spatially contiguous and their emission lines are spectrally close. It is partially detected as well in our observations of 13CO J = 1–0, J = 2–1 and J = 3–2, and also has a faint, partial counterpart in C18O J = 1–0 and J = 2–1. To understand the nature of this region we searched for counterparts in Spitzer Multiband Imaging Photometer (MIPS), WISE, DSS and XMM-Newton data; and in near-infrared and optical point source catalogs (Sect. 5), without success. Owing to projection effects, this apparent circular shape could also be explained by an unresolved and clumpy distribution of gas.\n3.Shocked clump: in the lower part of the field we identify a very bright clump emitting between v = −31.0 km s−1 and v = 16 km s−1. This structure of size ~2′ × 0.75′ (~ 1.1 × 0.4 pc), which is detected in the 12CO(3–2) transition as well, belongs to the southwestern ridge of the molecular shell of the SNR and has been described as a shocked molecular structure by several studies (van Dishoeck et al. 1993; Cesarsky et al. 1999; Snell et al. 2005; Shinn et al. 2011; Zhang et al. 2010). The core of the shocked clump (indicated by the letter “C” in Fig. 2) is also detected in 13CO in the transitions J = 1–0, J = 2–1, and J = 3–2, and in C18O J = 1–0 and J = 2–1.\n4.Shocked knot: an additional shocked knot (indicated by the letter “D” in Fig. 2) is also detected to the west of the previously described structure. This fainter and smaller structure is spatially separated from the main shocked clump.\n5.At the same position as the shocked clump and extending southward and westward, we find a faint, elongated clump emitting between v = 5.0 km s−1 and v = 7.5 km s−1. This structure (indicated by the symbol “*” in Fig. 2) spatially coincides with the shocked clump, yet the peak velocity is not exactly the same (see developments on kinematics of the region in Sect. 3.3). It has a faint counterpart in 13CO(1–0). Observations of the ambient molecular cloud by Lee et al. (2012) indicate this structure as part of a faint NE-SW complex of molecular gas in the velocity range +3 km s−1 vLSR +10 km s−1.\n6.Finally, the 13CO(1–0) map (Fig. 4, right panel and Fig. D.2) indicates a large clump of gas extending from the bottom center to the right end of the field, with a bright knot in the bottom right corner of the field. However, this structure has no bright, well-defined counterpart in any of the 12CO transitions maps. It is spatially and kinematically correlated with the faint and diffuse 12CO J = 1–0 and J = 2–1 emission seen in the velocity range −5.5 km s−1 vLSR −2 km s−1. From the comparison with the 12CO observations of Lee et al. (2012) and 13CO observations of Su et al. (2014) toward the SNR, we conclude that this structure is part of the western molecular complex observed in the velocity range −10 km s−1 vLSR 0 km s−1.\n","Citation Text":["Lee et al. (2012)"],"Citation Start End":[[4316,4333]]} {"Identifier":"2018MNRAS.480.3483M__Martin_&_Lee_1996_Instance_1","Paragraph":"The total energy at each point is defined as a sum of four separate components; the CCSD(T) energy extrapolated to the complete basis set (CBS) limit and three energy increments. Each increment represents a source of electron correlation omitted from the above CBS energy: core-correlation, scalar-relativistic correlation, and higher order dynamic correlation. A nomenclature has been used in the past to describe this composite theory by its components, where C represents CBS-extrapolation, cC represents core-correlation, R represents scalar-relativity, and E represents higher order correlation (Fortenberry et al. 2011). For example, the CcCRE potential surface (equation 2) includes all of the corrections, but the CcCR omits the higher order correlation correction. \n(2)\r\n\\begin{equation*}\r\nE_\\text{CcCRE} = E_\\text{CBS} + \\Delta E_\\text{core} + \\Delta E_\\text{rel} + \\Delta E_\\text{hlc}\r\n\\end{equation*}\r\nTwo different procedures are used to extrapolate the CCSD(T) energy to the CBS limit. The first scheme used is the three-point total energy extrapolation shown in equation (3, Martin & Lee 1996). \n(3)\r\n\\begin{equation*}\r\nE(X) = E_\\text{CBS}+ A(X+1\/2)^{-4} + B(X+1\/2)^{-6}\r\n\\end{equation*}\r\nThe second scheme extrapolates the Hartree–Fock energy and the correlation energy, represented here as ε, separately using equations (4) and (5), respectively (Feller 1993; Helgaker et al. 1997). \n(4)\r\n\\begin{equation*}\r\nE^\\text{HF}(X) = E^\\text{HF}_\\text{CBS} + A e^{BX}\r\n\\end{equation*}\r\n(5)\r\n\\begin{equation*}\r\n\\varepsilon ^\\text{(T)}(X) = \\varepsilon ^\\text{(T)}_\\text{CBS} + A X^{-3}\r\n\\end{equation*}\r\nThe resulting CCSD(T)\/CBS energy in this latter scheme is $E^{\\prime }_\\text{CBS} = E^\\text{HF}_\\text{CBS} + \\varepsilon ^\\text{(T)}_\\text{CBS}$, where the prime is simply used to distinguish the two CBS extrapolations. Each energy correction (increment) is defined as the difference between the energy with the correlation effect considered and the energy without it when using the same basis set. The core-correlation correction, ΔEcore, is EMTc − EMT as defined with the geometry correction. Scalar relativity is incorporated through ΔErel, which is taken as the difference in the all-electron CCSD(T)\/cc-pCV(T+d)Z-DK energy with and without the Douglas–Kroll–Hess (DKH) corrections to second-order (Reiher & Wolf 2004). The energy contribution from non-iterative quadruple excitations in the coupled cluster wavefunction, ΔEhlc, is defined as the difference between CCSDT(Q)\/cc-pV(T+d)Z and CCSD(T)\/cc-pV(T+d)Z at each point.","Citation Text":["Martin & Lee 1996"],"Citation Start End":[[1090,1107]]} {"Identifier":"2022MNRAS.509.2758G__Mannarelli_et_al._2007_Instance_1","Paragraph":"However, in our model, the interactions between strangeons are dominated by strong force. The detailed calculations of the shear modulus is still not performed, but it should be much larger than that of the NS’s crust. If the burst oscillation frequencies observed in low-mass X-ray binaries correspond to the first few torsional modes of SSs, the shear modulus should be about one thousand times of the NS’s crust, say $\\mu \\simeq 4\\times 10^{32}\\, \\rm erg\\, cm^{-3}$ (Xu 2003; Owen 2005). We do not know how large the tidal deformability will deviate from the fluid case for SSs, but we can obtain some key insights of this problem from the calculations of tidal deformabilities for crystalline colour superconducting phase (Lau, Leung & Lin 2017, 2019). QSs composed of crystalline colour superconducting phase are rigid with extremely high shear modulus (Alford, Bowers & Rajagopal 2001; Mannarelli, Rajagopal & Sharma 2007). The shear modulus is approximately given by (Mannarelli et al. 2007)\n(77)$$\\begin{eqnarray*}\r\n\\mu =2.47 \\, \\mathrm{MeV} \/ \\mathrm{fm}^{3}\\left(\\frac{\\Delta }{10 \\, \\mathrm{MeV}}\\right)^{2}\\left(\\frac{\\mu _{\\rm q}}{400 \\, \\mathrm{MeV}}\\right)^{2}\\, ,\r\n\\end{eqnarray*}$$where μq is the average quark chemical potential and Δ is the gap parameter which is in the range of 5–$25\\, \\rm MeV$. If the shear modulus is taken to be $\\mu =4\\times 10^{32}\\, \\rm erg\\, cm^{-3}$ ($\\Delta \\simeq 5\\, \\rm MeV$), according to the results in Lau et al. (2017, 2019), the deviations of the tidal deformabilities from the fluid case are in the order of $1{{\\ \\rm per\\ cent}}$. For larger gap parameters, the deviations can be very large and more interestingly, they found that the universal relations between the moment of inertia and tidal deformability will deviate from the ones for fluid stars. If we take the shear modulus to be about $\\mu \\simeq 4\\times 10^{32}\\, \\rm erg\\, cm^{-3}$, the corrections may not be very large and the results discussed in our work is a good approximation. But if the shear modulus is actually larger, then we need to consider the corrections due to the elasticity.","Citation Text":["Mannarelli et al. 2007"],"Citation Start End":[[975,997]]} {"Identifier":"2022ApJ...928...91C__Quintana_et_al._2016_Instance_1","Paragraph":"We derive leftover planetesimal populations directly from our simulations sets that incorporate planetesimals (see Table 1 and the left panel of Figure 1), and perform an additional batch of ∼105 simulations of the final few giant impacts in our systems to derive collisional fragment distributions. This additional suite of computations utilizes a modified version of the Mercury integration package described in Chambers (2013) that incorporates collisional parameter space mapped in Stewart & Leinhardt (2012) to track hit-and-run and fragmenting impacts. Aside from the fragmentation algorithm, the integration parameters (i.e., time step, ejection radius, etc.) are identical to those utilized in Section 2.1. To prevent the calculation from becoming intractable, the user must establish a minimum fragment mass (MFM; 0.005 M\n⊕ in our simulations based on previous experience with the code; Quintana et al. 2016; Clement et al. 2019b). When the algorithm detects a fragmenting collision, the total remnant mass is divided into a number of equal-mass fragments with M > M\nMFM that are ejected in uniformly spaced directions in the collisional plane at v ≃ 1.05v\nesc. If the total eroded mass is less than the MFM, the collision is considered totally accretionary. While this treatment of fragmentation is obviously somewhat contrived (see Section 4 for a discussion of some of these caveats), a first-order dissection of the distinctive populations of collisionally generated debris and unaltered planetesimals is important for our study as the fragment material might posses enhanced volatile and light element inventories if it is ejected from near the surface of partially or fully differentiated proto-planets. Moreover, since we utilize these simulations to infer the orbital distribution of debris given a supposed size frequency distribution (SFD), our particular selection of MFM is not carried forward into our study of late bombardment, and is therefore only important for keeping our experiments computationally feasible.","Citation Text":["Quintana et al. 2016"],"Citation Start End":[[896,916]]} {"Identifier":"2017ApJ...835..169O__Stalevski_et_al._2012_Instance_1","Paragraph":"Recent MIR studies have provided us with a much more realistic view of the central part of the AGNs. Spitzer studies of nearby Compton-thick AGNs have shown that even Compton-thick AGNs, especially low-luminosity ones, often show only modest to moderate silicate absorption at \n\n\n\n\n\n μm (e.g., Hao et al. 2007; Goulding et al. 2012). A classical smooth torus model, such as that of Pier & Krolik (1992), predicts deeper absorption in proportion to the X-ray absorption column density. On the other hand, if the torus is made of a collection of clouds, each cloud is heated to ∼300 K to emit MIR emission while absorbing the background light when the foreground cloud is cooler than the one behind. The radiation transfer effect among the clouds significantly reduces the net silicate absorption even when the torus is seen edge-on (Nenkova et al. 2002, 2008a, 2008b; Hönig et al. 2006; Hönig & Kishimoto 2010; Stalevski et al. 2012, 2016). Meanwhile, recent MIR interferometric studies of nearby AGNs have started to directly reveal the dust distribution in the vicinity of the AGNs at parsec scales. In some best-studied AGNs, extended optically thin dust emission elongated toward the system’s polar direction (e.g., direction of the extended narrow-line region or outflow) is typically found in addition to the compact disk-like component (e.g., Raban et al. 2009; Hönig et al. 2012, 2013; Tristram et al. 2012, 2014; López-Gonzaga et al. 2016; see also Asmus et al. 2016 for the single-dish study; see Netzer 2015 for a review). Such extended polar emission is clearly inconsistent with the classical idea of the dusty torus in the unification theory, and its nature is under debate. Some proposed ideas are that it originates from the inner funnel of an extended dust distribution above and below the torus and\/or the dusty outflow within the ionizing cone that is radiatively driven from the inner wall of the compact dusty torus (e.g., Hönig et al. 2012, 2013; Keating et al. 2012; Roth et al. 2012; Tristram et al. 2014).","Citation Text":["Stalevski et al. 2012"],"Citation Start End":[[910,931]]} {"Identifier":"2017ApJ...835..169OHao_et_al._2007_Instance_1","Paragraph":"Recent MIR studies have provided us with a much more realistic view of the central part of the AGNs. Spitzer studies of nearby Compton-thick AGNs have shown that even Compton-thick AGNs, especially low-luminosity ones, often show only modest to moderate silicate absorption at \n\n\n\n\n\n μm (e.g., Hao et al. 2007; Goulding et al. 2012). A classical smooth torus model, such as that of Pier & Krolik (1992), predicts deeper absorption in proportion to the X-ray absorption column density. On the other hand, if the torus is made of a collection of clouds, each cloud is heated to ∼300 K to emit MIR emission while absorbing the background light when the foreground cloud is cooler than the one behind. The radiation transfer effect among the clouds significantly reduces the net silicate absorption even when the torus is seen edge-on (Nenkova et al. 2002, 2008a, 2008b; Hönig et al. 2006; Hönig & Kishimoto 2010; Stalevski et al. 2012, 2016). Meanwhile, recent MIR interferometric studies of nearby AGNs have started to directly reveal the dust distribution in the vicinity of the AGNs at parsec scales. In some best-studied AGNs, extended optically thin dust emission elongated toward the system’s polar direction (e.g., direction of the extended narrow-line region or outflow) is typically found in addition to the compact disk-like component (e.g., Raban et al. 2009; Hönig et al. 2012, 2013; Tristram et al. 2012, 2014; López-Gonzaga et al. 2016; see also Asmus et al. 2016 for the single-dish study; see Netzer 2015 for a review). Such extended polar emission is clearly inconsistent with the classical idea of the dusty torus in the unification theory, and its nature is under debate. Some proposed ideas are that it originates from the inner funnel of an extended dust distribution above and below the torus and\/or the dusty outflow within the ionizing cone that is radiatively driven from the inner wall of the compact dusty torus (e.g., Hönig et al. 2012, 2013; Keating et al. 2012; Roth et al. 2012; Tristram et al. 2014).","Citation Text":["Hao et al. 2007"],"Citation Start End":[[294,309]]} {"Identifier":"2017ApJ...835..169OPier_&_Krolik_(1992)_Instance_1","Paragraph":"Recent MIR studies have provided us with a much more realistic view of the central part of the AGNs. Spitzer studies of nearby Compton-thick AGNs have shown that even Compton-thick AGNs, especially low-luminosity ones, often show only modest to moderate silicate absorption at \n\n\n\n\n\n μm (e.g., Hao et al. 2007; Goulding et al. 2012). A classical smooth torus model, such as that of Pier & Krolik (1992), predicts deeper absorption in proportion to the X-ray absorption column density. On the other hand, if the torus is made of a collection of clouds, each cloud is heated to ∼300 K to emit MIR emission while absorbing the background light when the foreground cloud is cooler than the one behind. The radiation transfer effect among the clouds significantly reduces the net silicate absorption even when the torus is seen edge-on (Nenkova et al. 2002, 2008a, 2008b; Hönig et al. 2006; Hönig & Kishimoto 2010; Stalevski et al. 2012, 2016). Meanwhile, recent MIR interferometric studies of nearby AGNs have started to directly reveal the dust distribution in the vicinity of the AGNs at parsec scales. In some best-studied AGNs, extended optically thin dust emission elongated toward the system’s polar direction (e.g., direction of the extended narrow-line region or outflow) is typically found in addition to the compact disk-like component (e.g., Raban et al. 2009; Hönig et al. 2012, 2013; Tristram et al. 2012, 2014; López-Gonzaga et al. 2016; see also Asmus et al. 2016 for the single-dish study; see Netzer 2015 for a review). Such extended polar emission is clearly inconsistent with the classical idea of the dusty torus in the unification theory, and its nature is under debate. Some proposed ideas are that it originates from the inner funnel of an extended dust distribution above and below the torus and\/or the dusty outflow within the ionizing cone that is radiatively driven from the inner wall of the compact dusty torus (e.g., Hönig et al. 2012, 2013; Keating et al. 2012; Roth et al. 2012; Tristram et al. 2014).","Citation Text":["Pier & Krolik (1992)"],"Citation Start End":[[382,402]]} {"Identifier":"2017ApJ...835..169OHönig_et_al._2012_Instance_1","Paragraph":"Recent MIR studies have provided us with a much more realistic view of the central part of the AGNs. Spitzer studies of nearby Compton-thick AGNs have shown that even Compton-thick AGNs, especially low-luminosity ones, often show only modest to moderate silicate absorption at \n\n\n\n\n\n μm (e.g., Hao et al. 2007; Goulding et al. 2012). A classical smooth torus model, such as that of Pier & Krolik (1992), predicts deeper absorption in proportion to the X-ray absorption column density. On the other hand, if the torus is made of a collection of clouds, each cloud is heated to ∼300 K to emit MIR emission while absorbing the background light when the foreground cloud is cooler than the one behind. The radiation transfer effect among the clouds significantly reduces the net silicate absorption even when the torus is seen edge-on (Nenkova et al. 2002, 2008a, 2008b; Hönig et al. 2006; Hönig & Kishimoto 2010; Stalevski et al. 2012, 2016). Meanwhile, recent MIR interferometric studies of nearby AGNs have started to directly reveal the dust distribution in the vicinity of the AGNs at parsec scales. In some best-studied AGNs, extended optically thin dust emission elongated toward the system’s polar direction (e.g., direction of the extended narrow-line region or outflow) is typically found in addition to the compact disk-like component (e.g., Raban et al. 2009; Hönig et al. 2012, 2013; Tristram et al. 2012, 2014; López-Gonzaga et al. 2016; see also Asmus et al. 2016 for the single-dish study; see Netzer 2015 for a review). Such extended polar emission is clearly inconsistent with the classical idea of the dusty torus in the unification theory, and its nature is under debate. Some proposed ideas are that it originates from the inner funnel of an extended dust distribution above and below the torus and\/or the dusty outflow within the ionizing cone that is radiatively driven from the inner wall of the compact dusty torus (e.g., Hönig et al. 2012, 2013; Keating et al. 2012; Roth et al. 2012; Tristram et al. 2014).","Citation Text":["Hönig et al. 2012"],"Citation Start End":[[1368,1385]]} {"Identifier":"2017ApJ...835..169OHönig_et_al._2012_Instance_2","Paragraph":"Recent MIR studies have provided us with a much more realistic view of the central part of the AGNs. Spitzer studies of nearby Compton-thick AGNs have shown that even Compton-thick AGNs, especially low-luminosity ones, often show only modest to moderate silicate absorption at \n\n\n\n\n\n μm (e.g., Hao et al. 2007; Goulding et al. 2012). A classical smooth torus model, such as that of Pier & Krolik (1992), predicts deeper absorption in proportion to the X-ray absorption column density. On the other hand, if the torus is made of a collection of clouds, each cloud is heated to ∼300 K to emit MIR emission while absorbing the background light when the foreground cloud is cooler than the one behind. The radiation transfer effect among the clouds significantly reduces the net silicate absorption even when the torus is seen edge-on (Nenkova et al. 2002, 2008a, 2008b; Hönig et al. 2006; Hönig & Kishimoto 2010; Stalevski et al. 2012, 2016). Meanwhile, recent MIR interferometric studies of nearby AGNs have started to directly reveal the dust distribution in the vicinity of the AGNs at parsec scales. In some best-studied AGNs, extended optically thin dust emission elongated toward the system’s polar direction (e.g., direction of the extended narrow-line region or outflow) is typically found in addition to the compact disk-like component (e.g., Raban et al. 2009; Hönig et al. 2012, 2013; Tristram et al. 2012, 2014; López-Gonzaga et al. 2016; see also Asmus et al. 2016 for the single-dish study; see Netzer 2015 for a review). Such extended polar emission is clearly inconsistent with the classical idea of the dusty torus in the unification theory, and its nature is under debate. Some proposed ideas are that it originates from the inner funnel of an extended dust distribution above and below the torus and\/or the dusty outflow within the ionizing cone that is radiatively driven from the inner wall of the compact dusty torus (e.g., Hönig et al. 2012, 2013; Keating et al. 2012; Roth et al. 2012; Tristram et al. 2014).","Citation Text":["Hönig et al. 2012"],"Citation Start End":[[1943,1960]]} {"Identifier":"2015MNRAS.450.1514C__Bond_et_al._1991_Instance_1","Paragraph":"The EPS model developed by Bond et al. (1991) is based on the excursion set formalism. For each collapsed region one constructs random ‘trajectories’ of the linear density contrast δ(M) as a function of the variance σ2(M). Defining\n\n(3)\n\n\\begin{equation}\n\\omega \\equiv \\delta _{\\rm c}(z)\\quad {\\rm {and}}\\quad S\\equiv \\sigma ^{2}(M),\n\\end{equation}\n\nwe use ω and S to label redshift and mass, respectively. If the initial density field is a Gaussian random field smoothed under a sharp k-space filter, increasing S (corresponding to a decreased in the filter mass M) results in δ(M) starting to wander away from zero, executing a random walk. The fraction of matter in collapsed objects in the mass interval M, M + dM at redshift z is associated with the fraction of trajectories that have their first upcrossing through the barrier ω in the interval S, S + dS, which is given by (Bond et al. 1991; Bower 1991; Lacey & Cole 1993)\n\n(4)\n\n\\begin{equation}\nf(S,\\omega ){\\rm d}S=\\frac{1}{\\sqrt{2\\pi }}\\frac{\\omega }{S^{3\/2}}\\rm {exp}\\left[-\\frac{\\omega ^{2}}{2S}\\right]dS,\n\\end{equation}\n\nwhere S is defined as\n\n(5)\n\n\\begin{equation}\nS(M) = \\frac{1}{2\\pi ^{2}}\\int _{0}^{\\infty }P(k)\\hat{W}^{2}(k;R)k^{2}{\\rm d}k.\n\\end{equation}\n\nHere P(k) is the linear power spectrum and $\\hat{W}(k;R)$ is the Fourier transform of a top hat window function. The probability function in equation (4) yields the PS mass function and gives the probability for a change ΔS in a time-step Δω, since for random walks the upcrossing probabilities are a Markov process (i.e. are independent of the path taken). The analytic function given by equation (4) provides the basis for the construction of merger trees. Neistein et al. (2006) derived a differential equation for the average halo mass history over an ensemble of merger trees from the EPS formalism. Defining MEPS(z) to be the mass of the most massive halo (main progenitor), along the main branch of the merger tree, as a function of redshift, they obtained the differential equation (see derivation in Appendix A)\n\n(6)\n\n\\begin{eqnarray}\n\\frac{{\\rm d}M_{\\rm {EPS}}}{{\\rm d}z}&=& \\sqrt{\\frac{2}{\\pi }}\\frac{M_{\\rm {EPS}}}{\\sqrt{S_{q}-S}}\\frac{1.686}{D(z)^{2}}\\frac{{\\rm d}D(z)}{{\\rm d}z},\n\\end{eqnarray}\n\nwhere Sq = S(MEPS(z)\/q) and S = S(MEPS(z)). The value of q needs to be obtained empirically so that MEPS reproduces halo mass histories from cosmological simulations. Neistein et al. (2006) showed that the uncertainty of q is an intrinsic property of EPS theory, where different algorithms for constructing merger trees may correspond to different values of q.","Citation Text":["Bond et al. (1991)"],"Citation Start End":[[27,45]]} {"Identifier":"2015MNRAS.450.1514C__Bond_et_al._1991_Instance_2","Paragraph":"The EPS model developed by Bond et al. (1991) is based on the excursion set formalism. For each collapsed region one constructs random ‘trajectories’ of the linear density contrast δ(M) as a function of the variance σ2(M). Defining\n\n(3)\n\n\\begin{equation}\n\\omega \\equiv \\delta _{\\rm c}(z)\\quad {\\rm {and}}\\quad S\\equiv \\sigma ^{2}(M),\n\\end{equation}\n\nwe use ω and S to label redshift and mass, respectively. If the initial density field is a Gaussian random field smoothed under a sharp k-space filter, increasing S (corresponding to a decreased in the filter mass M) results in δ(M) starting to wander away from zero, executing a random walk. The fraction of matter in collapsed objects in the mass interval M, M + dM at redshift z is associated with the fraction of trajectories that have their first upcrossing through the barrier ω in the interval S, S + dS, which is given by (Bond et al. 1991; Bower 1991; Lacey & Cole 1993)\n\n(4)\n\n\\begin{equation}\nf(S,\\omega ){\\rm d}S=\\frac{1}{\\sqrt{2\\pi }}\\frac{\\omega }{S^{3\/2}}\\rm {exp}\\left[-\\frac{\\omega ^{2}}{2S}\\right]dS,\n\\end{equation}\n\nwhere S is defined as\n\n(5)\n\n\\begin{equation}\nS(M) = \\frac{1}{2\\pi ^{2}}\\int _{0}^{\\infty }P(k)\\hat{W}^{2}(k;R)k^{2}{\\rm d}k.\n\\end{equation}\n\nHere P(k) is the linear power spectrum and $\\hat{W}(k;R)$ is the Fourier transform of a top hat window function. The probability function in equation (4) yields the PS mass function and gives the probability for a change ΔS in a time-step Δω, since for random walks the upcrossing probabilities are a Markov process (i.e. are independent of the path taken). The analytic function given by equation (4) provides the basis for the construction of merger trees. Neistein et al. (2006) derived a differential equation for the average halo mass history over an ensemble of merger trees from the EPS formalism. Defining MEPS(z) to be the mass of the most massive halo (main progenitor), along the main branch of the merger tree, as a function of redshift, they obtained the differential equation (see derivation in Appendix A)\n\n(6)\n\n\\begin{eqnarray}\n\\frac{{\\rm d}M_{\\rm {EPS}}}{{\\rm d}z}&=& \\sqrt{\\frac{2}{\\pi }}\\frac{M_{\\rm {EPS}}}{\\sqrt{S_{q}-S}}\\frac{1.686}{D(z)^{2}}\\frac{{\\rm d}D(z)}{{\\rm d}z},\n\\end{eqnarray}\n\nwhere Sq = S(MEPS(z)\/q) and S = S(MEPS(z)). The value of q needs to be obtained empirically so that MEPS reproduces halo mass histories from cosmological simulations. Neistein et al. (2006) showed that the uncertainty of q is an intrinsic property of EPS theory, where different algorithms for constructing merger trees may correspond to different values of q.","Citation Text":["Bond et al. 1991"],"Citation Start End":[[881,897]]} {"Identifier":"2021MNRAS.500..259S__Meiksin_&_White_1999_Instance_1","Paragraph":"Finally, putting everything together, and using dΩu = dϕvdθusin θu, the cross-correlation $\\rho _{\\ell \\ell ^{\\prime }ij}^{uv}(\\beta , b, \\bar{n}_{g})$ can be written as\n(28)$$\\begin{eqnarray*}\r\n\\rho _{\\ell \\ell ^{\\prime }ij}^{uv}(\\beta , b, \\bar{n}_{g}) = \\delta _{ij}^{K} \\frac{\\kappa _{\\ell \\ell ^{\\prime }}^{uv}(k_{i},\\beta ,b,\\bar{n}_{g})}{\\kappa _{\\ell \\ell ^{\\prime }}(k_{i},\\beta ,b,\\bar{n}_{g})},\r\n\\end{eqnarray*}$$with, at leading order in $(\\bar{n}_{g}P_m^\\mathrm{lin}(k))^{-1}$ (e.g. Meiksin & White 1999; Howlett & Percival 2017),\n(29)$$\\begin{eqnarray*}\r\n\\kappa _{\\ell \\ell ^{\\prime }}^{uv}(k,\\beta ,b,\\bar{n}_{g}) &=& \\int _{0}^{2\\pi } \\mathrm{ d}\\phi _{v} \\int _{0}^{\\pi } \\mathrm{ d}\\theta _{u}\\sin {\\theta _{u}} \\nonumber \\\\\r\n&&\\times \\, \\bigg[ b^{2}\\left(1 + \\beta \\cos ^{2}{\\theta _{u}}\\right) \\left(1 + \\beta \\cos ^{2}{\\theta _{v}}\\right) P_m^\\mathrm{lin}(k) \\nonumber \\\\\r\n&& +\\, \\frac{1}{\\bar{n}_{g}} e^{-k^{2}\\left(\\cos ^{2}{\\theta _{u}} + \\cos ^{2}{\\theta _{v}} - 2 \\cos {\\theta _{u}}\\cos {\\theta _{v}} \\cos \\theta _{uv} \\right) f^{2} \\sigma _{d}^{2}\/2} \\bigg]^{2} \\nonumber \\\\\r\n&&\\times \\, \\mathcal {L}_{\\ell }(\\cos {\\theta _{u}})\\mathcal {L}_{\\ell ^{\\prime }}(\\cos \\theta _{v}),\r\n\\end{eqnarray*}$$\n (30)$$\\begin{eqnarray*}\r\n&&\\kappa _{\\ell \\ell ^{\\prime }}(k,\\beta ,b,\\bar{n}_{g}) \\nonumber \\\\\r\n&&\\quad = 2\\pi \\int _{0}^{\\pi } \\mathrm{ d}\\theta _{u}\\sin {\\theta _{u}} \\left[ b^{2} \\left(1 + \\beta \\cos ^{2}{\\theta _{u}}\\right)^{2} P_m^\\mathrm{lin}(k) + \\frac{1}{\\bar{n}_{g}} \\right]^{2} \\nonumber \\\\\r\n&&\\qquad\\times \\, \\mathcal {L}_{\\ell }(\\cos {\\theta _{u}})\\mathcal {L}_{\\ell ^{\\prime }}(\\cos {\\theta _{u}}).\r\n\\end{eqnarray*}$$In the limit that there is no shot noise, $1\/\\bar{n}_{g} \\rightarrow 0$, and the $P_m^\\mathrm{lin}(k)$ in equation (29) cancels with the $P_m^\\mathrm{lin}(k)$ in equation (30), removing any k-dependence on the cross-correlation. If the LOS u and v are orthogonal, then we arrive at the same expression as equations (18) and (19).","Citation Text":["Meiksin & White 1999"],"Citation Start End":[[496,516]]} {"Identifier":"2022ApJ...927..237I__Fukushima_&_Yajima_2021_Instance_1","Paragraph":"In addition, star formation in the halo is modeled by assuming a conversion efficiency from gas into stars ϵ\n⋆. In our fiducial case, we adopt ϵ\n⋆ = 0.05 (e.g., Visbal et al. 2015), which is motivated by abundance matching and the observed UV luminosity function of galaxies at z ≃ 6 (Bouwens et al. 2015). Note that the efficiency is calculated as the average value over time and scales in galaxies. Alternatively, we suppose that a star formation episode with a high value of ϵ\n⋆ lasts within a few megayears in the nuclear region before SN explosions of massive stars begin to occur and regulate the star formation efficiency (SFE) in the bulge. According to numerical simulations that study star cluster formation from a giant molecular cloud with a size of 10–100 pc, the SFE becomes as high as ϵ\n⋆ ≳ 0.2–0.3 when the initial gas surface density is higher than ∼103\nM\n⊙ pc−2 (Fukushima et al. 2020; Fukushima & Yajima 2021). Referring to those observational and theoretical studies, we assume f\n\nn\n = f\n0(1 − ϵ\n⋆), where f\n0 = 1 and ϵ\n⋆ = 0.05 (fiducial case) and f\n0 = 4 and ϵ\n⋆ = 0.5 (high SFE case). Following the definition of the SFE, ϵ\n⋆, the SFR is approximated as\n32\n\n\n\nSFR=4πϵ⋆1−ϵ⋆ρ(r)r2Vc,≃0.11ϵ⋆f0Tvir,43\/2M⊙yr−1,\n\nwhere V\nc is the halo circular velocity. This SFR is used to estimate the emissivity of stellar irradiation (LW and X-rays) and to calculate the bulge growth in mass. Note that in most cases, the gas mass within r ≃ r\nc for the given initial condition is lower than the total mass of newly forming stars.\n10\n\n\n10\nAlthough we do not consider the self-gravity of gas in our simulations, it would dominate the bulge gravity at the intermediate scale of ∼O(10 pc) only in the early stage of the bulge formation where M\n⋆ ≲ 106\nM\n⊙. In this case, however, radiative feedback associated with BH accretion blows the gas outward, and then the gas self-gravity eventually becomes less important (see Section 3.2.2). Therefore, our star formation model implicitly assumes that the bulge growth is not led by in situ star formation but by efficient migration of stars formed at larger radii with morphological evolution owing to stellar relaxation (see also Appendix A).","Citation Text":["Fukushima & Yajima 2021"],"Citation Start End":[[904,927]]} {"Identifier":"2021ApJ...915L..13H__Descouvemont_et_al._2004_Instance_1","Paragraph":"To obtain reaction rates in a wide temperature range \n\n\n\n\n\n\nT\n\n\n9\n\n\n=\n0.001\n\n\n–10 (where T9 is in units of 109 K) for BBN calculation inputs, continuous excitation functions over \n\n\n\n\n\n\n10\n\n\n−\n8\n\n\n\n\n to a few MeV are needed for numerical integration. Therefore we performed an R-matrix analysis to compile both the present and the previous data of these three reaction channels by using AZURE2 (Azuma et al. 2010) including all the relevant partial widths \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n. The 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n data set used for the R-matrix analysis is based on the same selection as used in Damone et al. (2018), Damone (2018; part of Dam18 + Sek76 as displayed in Figure 2), and the present THM data, Bor63, and Pop76 are added. For the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n and 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n channels, all the labeled data shown in Figure 2 (except for p1 Tom19 and \n\n\n\n\nγ\nα\n\n\n Bar16) were used without any data cutoff. Appendix B shows the adopted data sets more explicitly. We included nine known levels below the 8Be excitation energy of \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\nMeV\n\n\n (Tilley et al. 2004) and an additional nonresonant background pole, with a common channel radius of 5 fm for each channel in the same manner as Adahchour & Descouvemont (2003). The most significant channel 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n0\n\n\n)\n\n\n7\n\n\n\n\nLi is dominated by four of these levels as described in detail by a former R-matrix study (Adahchour & Descouvemont 2003; Descouvemont et al. 2004); the 2− resonance near the neutron threshold (labeled as level I) principally dominates the cross section up to the BBN energies, the two 3+ states at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.24\n\nMeV\n\n\n (level II) and \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n21.5\n\nMeV\n\n\n well characterize the corresponding single peaks, and a 2+ background pole accounts for the enhancement at high energies. The most important resonances to expand analysis to the 7Be\n\n\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n7\n\n\n\n\nLi* and 7Be\n\n\n\n\n\n\n(\nn\n,\nα\n)\n\n\n4\n\n\n\n\nHe channels are the 1− state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.4\n\nMeV\n\n\n (level III) and the 2+ state at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.1\n\nMeV\n\n\n (level IV), respectively; the former expresses the 7Be\n\n\n\n\n(\nn\n,\n\n\np\n\n\n1\n\n\n)\n\n\n resonance behavior peaked at \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n0.5\n\nMeV\n\n\n tailing down to the thermal neutron energy by the \n\n\n\n\n1\n\n\/\n\nv\n\n\n law, and the latter forms the first peak in the 7Be\n\n\n\n\n(\nn\n,\nα\n)\n\n\n spectrum around \n\n\n\n\n\n\nE\n\n\nc\n.\nm\n.\n\n\n∼\n1\n\nMeV\n\n\n. Despite its importance in the \n\n\n\n\n(\nn\n,\nα\n)\n\n\n channel, level IV is much less significant in the total cross section especially at lower energies due to its p-wave nature. Therefore we imposed some restrictions on level IV, which made the analysis much simpler; fixing \n\n\n\n\n\n\nΓ\n\n\np\n0\n\n\n\n\n, \n\n\n\n\n\n\nΓ\n\n\np\n1\n\n\n\n\n, and \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\n at a known ratio \n\n\n\n\n\n\nΓ\n\n\nα\n\n\n\n\/\n\n\n\nΓ\n\n\np\n\n\n∼\n4.5\n\n\n (Tilley et al. 2004), and freeing \n\n\n\n\n\n\nΓ\n\n\nn\n\n\n\n\n and resonance energy (refitted to be 19.87 MeV) not to significantly exceed the known total width \n\n\n\n\nΓ\n=\n880\n\n\nkeV\n\n\n (Tilley et al. 2004). The other four higher-lying levels (0+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n20.2\n\nMeV\n\n\n, 2+ at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22.24\n\nMeV\n\n\n, 1− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n22\n\n\n MeV, and 2− at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n24\n\n\n MeV) play rather supplementary roles mainly for the higher-energy behavior. The 4+ and 4− higher-spin states (at \n\n\n\n\n\n\nE\n\n\nx\n\n\n=\n19.86\n\nMeV\n\n\n and 20.9 MeV, respectively) were not included due to their limited influences. We do not introduce the γ-emission channels to fit the Bar16 plots (representing the 7Be\n\n\n\n\n\n\n\n\nn\n,\nγ\nα\n\n\n\n\n4\n\n\n\n\nHe reaction channel Barbagallo et al. 2016), which appears significant only below the BBN energies. See Appendix C for more details on the present R-matrix analysis.","Citation Text":["Descouvemont et al. 2004"],"Citation Start End":[[1497,1521]]} {"Identifier":"2017ApJ...849...52N__Quataert_&_Gruzinov_2000_Instance_1","Paragraph":"The bolometric luminosity of 3C 84 is about 0.4% of the Eddington luminosity. Thus, the accretion flow of 3C 84 is likely to be a radiatively inefficient accretion flow (RIAF: Narayan & Yi 1995) rather than a standard disk (Shakura & Sunyaev 1973). However, we note that 3C 84 has a cold (\n\n\n\n\n\n\nT\n\n\ne\n\n\n∼\n\n\n10\n\n\n4\n\n\n\n\n K) disk-like accretion flow, as identified by FFA of the emission from the counter jet in the parsec scale (Walker et al. 2000) and inhomogeneous gas distribution around the black hole (Fujita et al. 2016). A number of theoretical studies predicted that the accretion flow components of hot geometrically thick (RIAF-like) and cold geometrically thin can coexist in either horizontal or vertical stratification (e.g., Miller & Stone 2000; Merloni & Fabian 2002; Liu et al. 2007; Ho 2008; Liu & Taam 2013). The measured Faraday rotation can be caused by such an RIAF-like component. We thus estimate the accretion rate of the RIAF-like component using the measured RM. For a simplicity, we assume that the RIAF-like component is a quasi-spherical Bondi accretion flow with a power-law density profile. We can calculate the accretion rate, following the formulation as follows (Quataert & Gruzinov 2000; Marrone et al. 2006; Kuo et al. 2014).\n\n\n\n\n\n\n\n\n\nM\n\n\n˙\n\n\n\n\n=\n\n\n1.3\n×\n\n\n10\n\n\n−\n10\n\n\n\n\n\n[\n\n1\n−\n\n\n\n(\n\n\n\nr\n\n\nout\n\n\n\n\/\n\n\n\nr\n\n\nin\n\n\n\n)\n\n\n\n−\n(\n3\nβ\n−\n1\n)\n\n\/\n\n2\n\n\n\n]\n\n\n\n−\n2\n\n\/\n\n3\n\n\n\n\n\n\n\n\n×\n\n\n\n\n\n\n\n\n\nM\n\n\nBH\n\n\n\n\n8.0\n×\n\n\n10\n\n\n8\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n\n\n\n\n\n4\n\n\/\n\n3\n\n\n\n\n\n\n\n\n\n2\n\n\n3\nβ\n−\n1\n\n\n\n\n\n\n\n−\n2\n\n\/\n\n3\n\n\n\n\nr\n\n\nin\n\n\n7\n\n\/\n\n6\n\n\n\n\n\n\n\n\n\nRM\n\n\nrad\n\n\n\nm\n\n\n−\n2\n\n\n\n\n\n\n\n\n\n2\n\n\/\n\n3\n\n\n.\n\n\n\n\n\nFor an inner effective radius \n\n\n\n\n\n\nr\n\n\nin\n\n\n\n\n of 1 pc (\n\n\n\n\n1.3\n×\n\n\n10\n\n\n4\n\n\n\n\nR\n\n\ns\n\n\n\n\n), where the hotspot is located, the observed RM implies an accretion rate of \n\n\n\n\n∼\n4.3\n×\n\n\n10\n\n\n−\n2\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n yr−1 and \n\n\n\n\n∼\n8.6\n×\n\n\n10\n\n\n−\n2\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n yr−1 for \n\n\n\n\nβ\n=\n0.5\n\n\n and \n\n\n\n\nβ\n=\n1.5\n\n\n, which are corresponding to convection-dominated accretion flow (CDAF: Narayan et al. 2000; Quataert & Gruzinov 2000) and advection-dominated accretion flow (ADAF: Ichimaru 1977; Narayan & Yi 1995), respectively. Here we assumed the outer effective radius \n\n\n\n\n\n\nr\n\n\nout\n\n\n\n\n of \n\n\n\n\n\n\n10\n\n\n5\n\n\n\n\nR\n\n\ns\n\n\n\n\n (∼8 pc), which is approximately the same with the Bondi radius of 8.6 pc (Fujita et al. 2016). The derived accretion rate is roughly consistent with that estimated from the bolometric luminosity with a black hole mass of \n\n\n\n\n8\n×\n\n\n10\n\n\n8\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n and a radiative efficiency of 10% (\n\n\n\n\n\n\nM\n\n\n˙\n\n\n∼\n\n\nL\n\n\nbol\n\n\n\n\/\n\n(\n0.1\n\n\nc\n\n\n2\n\n\n)\n≃\n7.1\n\n×\n\n\n10\n\n\n−\n2\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n yr−1).","Citation Text":["Quataert & Gruzinov 2000"],"Citation Start End":[[1196,1220]]} {"Identifier":"2017ApJ...849...52N__Quataert_&_Gruzinov_2000_Instance_2","Paragraph":"The bolometric luminosity of 3C 84 is about 0.4% of the Eddington luminosity. Thus, the accretion flow of 3C 84 is likely to be a radiatively inefficient accretion flow (RIAF: Narayan & Yi 1995) rather than a standard disk (Shakura & Sunyaev 1973). However, we note that 3C 84 has a cold (\n\n\n\n\n\n\nT\n\n\ne\n\n\n∼\n\n\n10\n\n\n4\n\n\n\n\n K) disk-like accretion flow, as identified by FFA of the emission from the counter jet in the parsec scale (Walker et al. 2000) and inhomogeneous gas distribution around the black hole (Fujita et al. 2016). A number of theoretical studies predicted that the accretion flow components of hot geometrically thick (RIAF-like) and cold geometrically thin can coexist in either horizontal or vertical stratification (e.g., Miller & Stone 2000; Merloni & Fabian 2002; Liu et al. 2007; Ho 2008; Liu & Taam 2013). The measured Faraday rotation can be caused by such an RIAF-like component. We thus estimate the accretion rate of the RIAF-like component using the measured RM. For a simplicity, we assume that the RIAF-like component is a quasi-spherical Bondi accretion flow with a power-law density profile. We can calculate the accretion rate, following the formulation as follows (Quataert & Gruzinov 2000; Marrone et al. 2006; Kuo et al. 2014).\n\n\n\n\n\n\n\n\n\nM\n\n\n˙\n\n\n\n\n=\n\n\n1.3\n×\n\n\n10\n\n\n−\n10\n\n\n\n\n\n[\n\n1\n−\n\n\n\n(\n\n\n\nr\n\n\nout\n\n\n\n\/\n\n\n\nr\n\n\nin\n\n\n\n)\n\n\n\n−\n(\n3\nβ\n−\n1\n)\n\n\/\n\n2\n\n\n\n]\n\n\n\n−\n2\n\n\/\n\n3\n\n\n\n\n\n\n\n\n×\n\n\n\n\n\n\n\n\n\nM\n\n\nBH\n\n\n\n\n8.0\n×\n\n\n10\n\n\n8\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n\n\n\n\n\n4\n\n\/\n\n3\n\n\n\n\n\n\n\n\n\n2\n\n\n3\nβ\n−\n1\n\n\n\n\n\n\n\n−\n2\n\n\/\n\n3\n\n\n\n\nr\n\n\nin\n\n\n7\n\n\/\n\n6\n\n\n\n\n\n\n\n\n\nRM\n\n\nrad\n\n\n\nm\n\n\n−\n2\n\n\n\n\n\n\n\n\n\n2\n\n\/\n\n3\n\n\n.\n\n\n\n\n\nFor an inner effective radius \n\n\n\n\n\n\nr\n\n\nin\n\n\n\n\n of 1 pc (\n\n\n\n\n1.3\n×\n\n\n10\n\n\n4\n\n\n\n\nR\n\n\ns\n\n\n\n\n), where the hotspot is located, the observed RM implies an accretion rate of \n\n\n\n\n∼\n4.3\n×\n\n\n10\n\n\n−\n2\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n yr−1 and \n\n\n\n\n∼\n8.6\n×\n\n\n10\n\n\n−\n2\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n yr−1 for \n\n\n\n\nβ\n=\n0.5\n\n\n and \n\n\n\n\nβ\n=\n1.5\n\n\n, which are corresponding to convection-dominated accretion flow (CDAF: Narayan et al. 2000; Quataert & Gruzinov 2000) and advection-dominated accretion flow (ADAF: Ichimaru 1977; Narayan & Yi 1995), respectively. Here we assumed the outer effective radius \n\n\n\n\n\n\nr\n\n\nout\n\n\n\n\n of \n\n\n\n\n\n\n10\n\n\n5\n\n\n\n\nR\n\n\ns\n\n\n\n\n (∼8 pc), which is approximately the same with the Bondi radius of 8.6 pc (Fujita et al. 2016). The derived accretion rate is roughly consistent with that estimated from the bolometric luminosity with a black hole mass of \n\n\n\n\n8\n×\n\n\n10\n\n\n8\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n and a radiative efficiency of 10% (\n\n\n\n\n\n\nM\n\n\n˙\n\n\n∼\n\n\nL\n\n\nbol\n\n\n\n\/\n\n(\n0.1\n\n\nc\n\n\n2\n\n\n)\n≃\n7.1\n\n×\n\n\n10\n\n\n−\n2\n\n\n\n\nM\n\n\n⊙\n\n\n\n\n yr−1).","Citation Text":["Quataert & Gruzinov 2000"],"Citation Start End":[[1971,1995]]} {"Identifier":"2020AandA...635A.137L__Li_et_al._2015_Instance_1","Paragraph":"We tested the optimization of the physical model for each of these candidates. For each candidate, we constructed a grid of parameters (λL, βL, ϕ0, ψ0, Ia, Ib). The grid for the orientation of the angular momentum vector was constructed by distributing ten different positions evenly on the celestial sphere. Standard Euler angles at t0 were arranged at 60° intervals. In addition, the moments of inertia were sequenced at 0.01 intervals from 0.01 to 0.99 in the case of SAM, and intervals of 0.1 from 1.1 to 10 in the case of LAM. Optimization was performed using the grid as the initial parameter set. The photometric model of the surface properties of airless body was considered as the Hapke model (Hapke 1993). The Hapke model parameters were optimized using initial values of a typical S-type asteroid: ϖ = 0.23, g = −0.27, h = 0.08, B0 = 1.6, and \n\n$\\bar{\\theta} = 20^{\\circ}$\n\n\n\nθ\n¯\n\n=\n\n20\n°\n\n\n\n (Li et al. 2015), where ϖ denotes the single scattering albedo, g denotes the particle phase function parameter, h and B0 respectively denote the width and amplitude of the opposition surge, and \n\n$\\bar{\\theta}$\n\n\nθ\n¯\n\n\n denotes the macroscopic roughness angle. Additionally, because the light curves used in this study covered only phases angles from 14.0° to 28.5°, the parameters for opposition surge (h and B0) were fixed during the optimization process. The \n\n$\\bar{\\theta}$\n\n\nθ\n¯\n\n\n was also fixed because it cannot be reliably obtained from our data. Thus, only two parameters, ϖ and g, were optimized. We found that the physical model is not sensitive to the Hapke model parameters. Solutions corresponding to the 2016 and 2017 data converged at one or two global minima for each frequency combination. However, we found that the values between the moment of inertia obtained from the shape model (assuming constant density) and the dynamical moments of inertia were different in all solutions except for SAM1. Because we preferred the physically self-consistent model, we excluded the combination of LAM and SAM2. In addition, solutions corresponding to the 2016 and 2017 data were similar to SAM1. Therefore, we accepted values for Pψ and Pϕ based on SAM1.","Citation Text":["Li et al. 2015"],"Citation Start End":[[905,919]]} {"Identifier":"2019ApJ...883..168R___2013b_Instance_1","Paragraph":"We conclude by displaying in Figure 9 the NS moment of inertia calculated from the EoSs without Δ's and with Δ's (with couplings xσΔ = xωΔ = 1.15 and xρΔ = 0). The results have been obtained by solving Hartle’s slow-rotation differential equation for the moment of inertia in general relativity coupled to the TOV equations (Hartle 1967). Astronomical observations of binary pulsars may provide information on the moment of inertia of NSs, ultimately offering possible limits on the underlying EoS (Lattimer & Schutz 2005). The only double-pulsar system known to date is PSR J0737-3039. The mass of its primary component PSR J0737-3039A, or pulsar A, is of 1.338 M⊙. It is expected that a precise measurement regarding the moment of inertia of this slowly rotating pulsar will be obtained in the near future from radio observations of PSR J0737-3039 (Burgay et al. 2003; Lyne et al. 2004). In a recent work, Landry & Kumar (2018) (also see Kumar & Landry 2019) use approximately universal relations among NS observables (Yagi & Yunes 2013a, 2013b), known as the binary-Love and I-Love relations (recall that the tidal deformability is related to the Love number), to determine a range of \n\n\n\n\n\n g cm2 for I of pulsar A from the 90% credible limits on the tidal deformability of a 1.4 M⊙ NS reported by LIGO-Virgo from the GW170817 event (Abbott et al. 2019). Landry & Kumar (2018) also facilitate a wider range I ≤ 1.67 × 1045 g cm2 for I of pulsar A from the less restrictive upper limit on the tidal deformability obtained by the LIGO-Virgo collaboration in their initial data analysis of GW170817 in Abbott et al. (2017). We have plotted in Figure 9 these two constraints reported in Landry & Kumar (2018) for I of pulsar A (we show both of the constraints because there may be a certain dependence on the analysis and on the assumed boundaries for Λ of a 1.4 M⊙ star). We can see in Figure 9 that the moment of inertia is an observable highly sensitive to the existence of Δ isobars in the composition of the core of the star. The presence of these particles, in particular for smaller values of the coupling of the Δ to the ρ-meson, improves the agreement with the constraints on the moment of inertia of pulsar A, whose measurement is anticipated within the next few years.","Citation Text":["Yagi & Yunes","2013b"],"Citation Start End":[[1021,1033],[1041,1046]]} {"Identifier":"2022MNRAS.512.2489O__Dado_&_Dar_2015_Instance_1","Paragraph":"The radioactive contribution to the light curve follows the analytic estimation of Dado & Dar (2015) exactly, taking as inputs from our models the Ni mass (Table 1), the ejecta asymptotic velocity, Vej, and the ejecta mass, $\\mathcal {M}_{\\rm ej}$. All these quantities are approximate and not the result of a sufficiently long and detailed calculation. We estimate an upper bound to the ejecta mass as the difference between the stellar mass at the brink of collapse, M0, and the PNS mass at tpb = tf (i.e. $\\mathcal {M}_{\\rm ej}:=M_0-M_{{\\small PNS}}(t_{\\rm f})$). We note that $\\mathcal {M}_{\\rm ej}$ is significantly greater than the mass unbound at tpb = tf (Mej; see Fig. 3) or the mass enclosed by the shock at that time (Msh, e; Table 1). At tpb = tf the explosion is ongoing and both Mej and Msh, e are still increasing until they reach their final values. The asymptotic ejecta velocity is estimated as $V_{\\rm ej}=\\sqrt{2E_{\\rm k}\/\\mathcal {M}_{\\rm ej}} = \\sqrt{2 (\\mathcal {T}_{{\\small PNS}}f_{\\rm er} + E_{\\rm exp})\/ \\mathcal {M}_{\\rm ej}}\\approx \\sqrt{2 \\mathcal {T}_{{\\small PNS}}f_{\\rm er} \/ \\mathcal {M}_{\\rm ej}}$, where we allow for the possibility that only a fraction fer of the PNS rotational energy can be converted into kinetic energy of the ejecta, Ek. The last approximation results from the fact that the $\\mathcal {T}_{{\\small PNS}}$ ($\\gt 10^{52}\\,$erg) is one order of magnitude (or more) greater than Eexp ($\\lt 2\\times 10^{51}\\,$ erg; see Table 1). Typical ejecta velocities in all our models are $V_{\\rm ej} \\approx (0.4-1.6)\\times 10^{9}\\, \\rm{cm\\,s}^{-1}$. The corresponding luminosity reads (Dado & Dar 2015)\n(8)$$\\begin{eqnarray}\r\nL_{\\mathrm{nuc}}(t)=\\frac{{\\rm e}^{-t^{2} \/ 2 t_{\\mathrm{r}}^{2}}}{t_{\\mathrm{r}}^{2}} \\int _{0}^{t} x {\\rm e}^{x^{2} \/ 2 t_{\\mathrm{r}}^{2}} \\skew{4}\\dot{E} \\, {\\rm d} x ,\r\n\\end{eqnarray}$$where\n(9)$$\\begin{eqnarray}\r\nt_{\\rm r}=\\sqrt{ \\frac{3\\mathcal {M}_{\\rm ej}f_{\\rm e} \\sigma _{\\rm T}}{8\\pi m_{\\rm p} c V_{\\rm ej}} },\r\n\\end{eqnarray}$$σT is the Thompson cross-section, mp is the proton mass, c is the speed of light, fe ≈ 0.275 is the fraction of free electrons, and $\\skew{4}\\dot{E}=\\skew{4}\\dot{E}_\\gamma + \\skew{4}\\dot{E}_{e^+}$, where\n(10)$$\\begin{eqnarray}\r\n\\skew{4}\\dot{E}_{\\gamma } &=& \\frac{M_\\mathrm{Ni}}{{\\rm M}_{\\odot }}\\left[7.78 A_{\\gamma }^\\mathrm{Ni} {\\rm e}^{-t \/ 8.76 \\mathrm{~d}}\\right. \\\\\r\n&&\\left.+\\,1.50 A_{\\gamma }^\\mathrm{Co}\\left[{\\rm e}^{-t \/ 111.27 \\mathrm{~d}}-{\\rm e}^{-t \/ 8.76 \\mathrm{~d}}\\right]\\right] 10^{43} \\mathrm{erg}\\, \\mathrm{s}^{-1}\r\n\\end{eqnarray}$$is the power supplied by gamma rays, and\n(11)$$\\begin{eqnarray}\r\n\\skew{4}\\dot{E}_{\\mathrm{e}^{+}} = \\frac{M_\\mathrm{Ni}}{{\\rm M}_{\\odot }} A_{\\mathrm{e}} \\left[{\\rm e}^{-t \/ 111.27 \\mathrm{~d}}-{\\rm e}^{-t \/ 8.76 \\mathrm{~d}}\\right] 10^{43} \\mathrm{erg}\\, \\mathrm{s}^{-1}\r\n\\end{eqnarray}$$is the power supply in the form of the kinetic energy of positrons. Ae ≈ 0.05 is the ratio of the energy released as positron kinetic energy and as gamma-ray energy in the decay of 56Co. $A_\\gamma ^\\mathrm{Ni}$ and $A_\\gamma ^\\mathrm{Co}$ are the absorbed fractions of the gamma-ray energy in the SN ejecta from the decay of 56Ni (decay time of 8.76 days) and 56Co (111.27 days), respectively. They are computed as $A_\\gamma \\approx 1-{\\rm e}^{-\\tau _\\gamma }$, with $\\tau _\\gamma =3\\mathcal {M}_{\\rm ej}\\sigma _t\/(8\\pi m_p V^2_{\\rm ej}t^2)$, and $\\sigma _t=9.5\\times 10^{-26}\\,$ cm2 ($\\sigma _t=8.7\\times 10^{-26}\\,$ cm2) for 56Ni (56Co).","Citation Text":["Dado & Dar (2015)"],"Citation Start End":[[83,100]]} {"Identifier":"2022MNRAS.512.2489O__Dado_&_Dar_2015_Instance_2","Paragraph":"The radioactive contribution to the light curve follows the analytic estimation of Dado & Dar (2015) exactly, taking as inputs from our models the Ni mass (Table 1), the ejecta asymptotic velocity, Vej, and the ejecta mass, $\\mathcal {M}_{\\rm ej}$. All these quantities are approximate and not the result of a sufficiently long and detailed calculation. We estimate an upper bound to the ejecta mass as the difference between the stellar mass at the brink of collapse, M0, and the PNS mass at tpb = tf (i.e. $\\mathcal {M}_{\\rm ej}:=M_0-M_{{\\small PNS}}(t_{\\rm f})$). We note that $\\mathcal {M}_{\\rm ej}$ is significantly greater than the mass unbound at tpb = tf (Mej; see Fig. 3) or the mass enclosed by the shock at that time (Msh, e; Table 1). At tpb = tf the explosion is ongoing and both Mej and Msh, e are still increasing until they reach their final values. The asymptotic ejecta velocity is estimated as $V_{\\rm ej}=\\sqrt{2E_{\\rm k}\/\\mathcal {M}_{\\rm ej}} = \\sqrt{2 (\\mathcal {T}_{{\\small PNS}}f_{\\rm er} + E_{\\rm exp})\/ \\mathcal {M}_{\\rm ej}}\\approx \\sqrt{2 \\mathcal {T}_{{\\small PNS}}f_{\\rm er} \/ \\mathcal {M}_{\\rm ej}}$, where we allow for the possibility that only a fraction fer of the PNS rotational energy can be converted into kinetic energy of the ejecta, Ek. The last approximation results from the fact that the $\\mathcal {T}_{{\\small PNS}}$ ($\\gt 10^{52}\\,$erg) is one order of magnitude (or more) greater than Eexp ($\\lt 2\\times 10^{51}\\,$ erg; see Table 1). Typical ejecta velocities in all our models are $V_{\\rm ej} \\approx (0.4-1.6)\\times 10^{9}\\, \\rm{cm\\,s}^{-1}$. The corresponding luminosity reads (Dado & Dar 2015)\n(8)$$\\begin{eqnarray}\r\nL_{\\mathrm{nuc}}(t)=\\frac{{\\rm e}^{-t^{2} \/ 2 t_{\\mathrm{r}}^{2}}}{t_{\\mathrm{r}}^{2}} \\int _{0}^{t} x {\\rm e}^{x^{2} \/ 2 t_{\\mathrm{r}}^{2}} \\skew{4}\\dot{E} \\, {\\rm d} x ,\r\n\\end{eqnarray}$$where\n(9)$$\\begin{eqnarray}\r\nt_{\\rm r}=\\sqrt{ \\frac{3\\mathcal {M}_{\\rm ej}f_{\\rm e} \\sigma _{\\rm T}}{8\\pi m_{\\rm p} c V_{\\rm ej}} },\r\n\\end{eqnarray}$$σT is the Thompson cross-section, mp is the proton mass, c is the speed of light, fe ≈ 0.275 is the fraction of free electrons, and $\\skew{4}\\dot{E}=\\skew{4}\\dot{E}_\\gamma + \\skew{4}\\dot{E}_{e^+}$, where\n(10)$$\\begin{eqnarray}\r\n\\skew{4}\\dot{E}_{\\gamma } &=& \\frac{M_\\mathrm{Ni}}{{\\rm M}_{\\odot }}\\left[7.78 A_{\\gamma }^\\mathrm{Ni} {\\rm e}^{-t \/ 8.76 \\mathrm{~d}}\\right. \\\\\r\n&&\\left.+\\,1.50 A_{\\gamma }^\\mathrm{Co}\\left[{\\rm e}^{-t \/ 111.27 \\mathrm{~d}}-{\\rm e}^{-t \/ 8.76 \\mathrm{~d}}\\right]\\right] 10^{43} \\mathrm{erg}\\, \\mathrm{s}^{-1}\r\n\\end{eqnarray}$$is the power supplied by gamma rays, and\n(11)$$\\begin{eqnarray}\r\n\\skew{4}\\dot{E}_{\\mathrm{e}^{+}} = \\frac{M_\\mathrm{Ni}}{{\\rm M}_{\\odot }} A_{\\mathrm{e}} \\left[{\\rm e}^{-t \/ 111.27 \\mathrm{~d}}-{\\rm e}^{-t \/ 8.76 \\mathrm{~d}}\\right] 10^{43} \\mathrm{erg}\\, \\mathrm{s}^{-1}\r\n\\end{eqnarray}$$is the power supply in the form of the kinetic energy of positrons. Ae ≈ 0.05 is the ratio of the energy released as positron kinetic energy and as gamma-ray energy in the decay of 56Co. $A_\\gamma ^\\mathrm{Ni}$ and $A_\\gamma ^\\mathrm{Co}$ are the absorbed fractions of the gamma-ray energy in the SN ejecta from the decay of 56Ni (decay time of 8.76 days) and 56Co (111.27 days), respectively. They are computed as $A_\\gamma \\approx 1-{\\rm e}^{-\\tau _\\gamma }$, with $\\tau _\\gamma =3\\mathcal {M}_{\\rm ej}\\sigma _t\/(8\\pi m_p V^2_{\\rm ej}t^2)$, and $\\sigma _t=9.5\\times 10^{-26}\\,$ cm2 ($\\sigma _t=8.7\\times 10^{-26}\\,$ cm2) for 56Ni (56Co).","Citation Text":["Dado & Dar 2015"],"Citation Start End":[[1628,1643]]} {"Identifier":"2021ApJ...923..116M__Marsch_et_al._1982_Instance_1","Paragraph":"Instabilities, driven by departures from local thermodynamic equilibrium (LTE), are frequently credited with affecting the behavior of rapidly evolving plasma systems, e.g., the expanding solar wind (Matthaeus et al. 2012). To quantify these departures, the underlying charged particle velocity distribution functions (VDFs) are typically modeled as bi-Maxwellians, having anisotropic temperatures T\n⊥,j\n and T\n∥,j\n with respect to the local magnetic field \nB\n; relative field-aligned drifts between each pair of constituent VDF components i and j being Δv\n\ni,j\n=(\nV\n\n\ni\n − \nV\n\n\nj\n) · \nB\n\/∣\nB\n∣; and temperature disequilibrium between species T\n\ni\n ≠ T\n\nj\n (Marsch et al. 1982). These anisotropies, drifts, and disequilibrium serve as distinct sources of free energy capable of driving the growth of a number of distinct unstable solutions (see, e.g., Section 5 of Verscharen et al. 2019). The presence of multiple free-energy sources makes it difficult to determine which subset of sources drives a given instability; parametric models accounting for a single source of free energy—e.g., the temperature anisotropy of a single population (Gary et al. 1997; Yoon 2017)—do not account for the diminishment or enhancement of predicted linear growth rates associated with the introduction of other departures from LTE, e.g., relative drifts of proton beams (Daughton & Gary 1998; Woodham et al. 2019; Liu et al. 2021), helium (Podesta & Gary 2011; Bourouaine et al. 2013; Verscharen et al. 2013), or their combined effects (Chen et al. 2016). To account for these effects, previous studies implemented Nyquist’s instability criterion (Nyquist 1932; Klein et al. 2017) on limited sets of in situ measurements from the Wind (Klein et al. 2018), Parker Solar Probe (Verniero et al. 2020; Klein et al. 2021), and Helios (Klein et al. 2019) missions, finding that a majority of intervals were unstable, that the kinds of waves driven unstable were very sensitive to the model used to describe the VDF, and that inclusion of multiple ion populations could both enhance or diminish the predicted growth rates.","Citation Text":["Marsch et al. 1982"],"Citation Start End":[[658,676]]} {"Identifier":"2018ApJ...852..112K__Aliu_et_al._2012_Instance_1","Paragraph":"The Virgo Cluster radio galaxy M87 (NGC 4486), located at a distance of \n\n\n\n\n\n Mpc (Mei et al. 2007) and believed to harbour a BH of mass \n\n\n\n\n\n, was the first extragalactic source detected at VHE energies (Aharonian et al. 2003). Given its proximity, M87 has been a prime target to probe scenarios for the formation of relativistic jets with high-resolution radio observations exploring scales down to some tens of rg, and much effort has recently been dedicated in this direction (e.g., Acciari et al. 2009; Doeleman et al. 2012; Hada et al. 2014, 2016; Akiyama et al. 2015, 2017; Kino et al. 2015). At VHE energies, M87 has revealed at least three active γ-ray episodes, during which day-scale flux variability (i.e., \n\n\n\n\n\n) has been observed (Aharonian et al. 2006; Albert et al. 2008; Acciari et al. 2009; Abramowski et al. 2012; Aliu et al. 2012). The VHE spectrum is compatible with a relatively hard power law (photon index ∼2.2) extending from 300 GeV to beyond 10 TeV, while the corresponding TeV output is relatively moderate, with an isotropic equivalent luminosity of \n\n\n\n\n\n erg s−1. The inner, parsec-scale jet in M87 is considered to be misaligned by \n\n\n\n\n\n–25°, resulting in modest Doppler boosting of its jet emission and creating challenges for conventional jet models to account for the observed VHE characteristics (see, e.g., Rieger & Aharonian 2012 for review and references). Gap-type emission models offer a promising alternative and different realizations have been proposed in the literature (e.g., Neronov & Aharonian 2007; Levinson & Rieger 2011; Broderick & Tchekhovskoy 2015; Vincent 2015; Ptitsyna & Neronov 2016). M87 is overall highly underluminous with characteristic estimates for its total nuclear (disk and jet) bolometric luminosity not exceeding \n\n\n\n\n\n erg s−1 by much (e.g., Owen et al. 2000; Whysong & Antonucci 2004; Prieto et al. 2016), suggesting that accretion onto its BH indeed occurs in a non-standard, advective-dominated (ADAF) mode characterized by an intrinsically low radiative efficiency (e.g., Di Matteo et al. 2003; Nemmen et al. 2014), with inferred accretion rates possibly ranging up to \n\n\n\n\n\n (e.g., Levinson & Rieger 2011) and a BH spin parameter close to its maximum one (e.g., Feng & Wu 2017). For these values of the accretion rate, the soft photon field (see Equations (2) and (3)) is sufficiently sparse that the maximum Lorentz factor \n\n\n\n\n\n of the magnetospheric particles is essentially determined by the curvature mechanism. The observed VHE variability is in principle compatible with \n\n\n\n\n\n, so that the different dependence of the gap power on β, Equation (20), does not necessarily (in the absence of other, intrinsic considerations of gap closure) imply a strong difference in the extractable gap powers. Figure 2 shows a representative point for M87 (taking \n\n\n\n\n\n). The observed VHE luminosity of M87 is some orders of magnitudes lower than the maximum possible gap power (given by the dotted line) and within the bound imposed by ADAF considerations (vertical line). The observed VHE flaring events thus appear consistent with a magnetospheric origin. VLBI observations of (delayed) radio core flux enhancements indeed provide support for the proposal that the variable VHE emission in M87 originates at the jet base very near to the BH (e.g., Acciari et al. 2009; Beilicke 2012; Hada et al. 2012, 2014).","Citation Text":["Aliu et al. 2012"],"Citation Start End":[[836,852]]} {"Identifier":"2019MNRAS.489.2417A__Kennicutt_1998_Instance_1","Paragraph":"In addition to the photons from the UVB, accounted for in Haardt Madau (2001) (HM01), ionizing photons ($\\rm h\\nu \\ge 1\\, Ryd$) emitted by nearby young stars, in particular these belonging to the halo in consideration, can contribute substantially to the total Ly emission of star-forming galaxies. The strength of this contribution depends strongly on the interstellar dust and gas geometry and kinematics (Kunth etal. 2003; Verhamme etal. 2012), as those determine how many Ly photons escape from the star-forming regions. In a first, conservative approximation, we assume that all the ionizing photons from stars are absorbed by dust or photoionizing neutral gas in the ISM. Since the dust attenuation is poorly constrained at low redshift, we will consider a simplistic model for the emitted Ly$\\rm \\alpha$ photons. We start with the prescription from Furlanetto etal. (2005) to estimate the intrinsic Ly luminosity from ionizing photons in the absence of dust: $L\\rm ^{stars}_{Ly\\alpha } \\ [erg\\, s^{-1}] = 10^{42}\\ SFR\\ [M_{\\odot }\\ yr^{-1}]$. We compute the SFR of each halo from the mass of young stars, using the continuous star formation approximation (Kennicutt 1998):\n\n(1)\n$$\\begin{eqnarray*}\r\n\\rm SFR [M_{\\odot }\\, yr^{-1}] = \\frac{\\mathit{ M}_{stars \\lt 10^8\\ yr}\\ [M_{\\odot }]}{10^8\\ [yr]}.\r\n\\end{eqnarray*}\r\n$$\nUsing COS data of low-redshift ($z \\sim 0.03$) star-forming galaxies, Wofford, Leitherer Salzer (2013) measured a Ly escape fraction ranging from 1percent to $\\rm 10{{\\ \\rm per\\ cent}}$. They estimate that this fraction is sensitive to the presence of dust and to the Hi column density, the Ly photons escaping more easily from holes of low Hi and dust column densities, resulting in a large scatter. Winds can also have a strong effect and can help Ly photons to escape (Dijkstra Jeeson-Daniel 2013) but we do not consider winds in our model. As we do not have any model for either the dust or radiative transfer, we will stay conservative in our assumptions. Hayes etal. (2011) find Ly escape fractions between $\\rm 0.1{{\\ \\rm per\\ cent}}$ and $\\rm 1{{\\ \\rm per\\ cent}}$ for low-z galaxies. Therefore, we will consider two extreme cases for the Ly luminosity from the stellar contribution at low redshift: one with a Ly escape fraction of $\\rm 1{{\\ \\rm per\\ cent}}$, and another with a Ly escape fraction of $\\rm 0.1{{\\ \\rm per\\ cent}}$. At higher redshift (z 1), we adopt a Ly escape fraction of $\\rm 10{{\\ \\rm per\\ cent}}$ that is within the prediction of Hayes etal. (2011). We are aware that different works predict very different escape fractions for Ly (e.g. Wofford etal. 2013; Naidu etal. 2017, but we choose to follow the trend observed in Hayes etal. (2011). Predicting the spatial and spectral profiles of such emission would require the full calculation from radiative transfer techniques (Verhamme etal. 2006, 2012; Rosdahl etal. 2013; Lake etal. 2015), which is beyond the scope of this work. However, as our goal is to study the detectability of such emission with upcoming instruments, we chose to make the simple assumption that all the Ly photons only go through one absorption\/re-emission process before leaving the cloud. Also, we assume that all of the Ly photons are emitted from the centre of the galaxy. We then weigh the profile proportionally to the total hydrogen density of the gas cell and by its inverse squared distance to the centre. This gives us, for each cell j the luminosity $L_{j}^{\\star }$:\n\n(2)\n$$\\begin{eqnarray*}\r\nL_{j}^{\\star }\\rm [erg\\, s^{-1}] = \\mathit{ f}_{esc} (Ly\\alpha) \\frac{\\frac{\\mathit{ n}_{\\mathit{ j},H}}{\\mathit{ R}_\\mathit{ j}^2}}{\\int _{\\mathit{ R}_{vir}} \\frac{\\mathit{ n}_H}{\\mathit{ R}^2}} 10^{42} SFR_\\mathit{ j}\\, [M_{\\odot }\\, yr^{-1}] .\r\n\\end{eqnarray*}\r\n$$\n","Citation Text":["Kennicutt 1998"],"Citation Start End":[[1163,1177]]} {"Identifier":"2018ApJ...860....8X__Ghirlanda_et_al._2004a_Instance_2","Paragraph":"For GRB 140629A, our analysis suggests that the optical and X-ray afterglows are from a narrow jet (\n\n\n\n\n\n rad) with a low B \n\n\n\n\n\n in a dense medium (n = 60 cm−3). In addition, the radiation efficiency of GRB 140629A is extremely low. We test whether or not it satisfies various empirical relations reported in the literature derived from observations of the prompt gamma-ray phase and the multi-wavelength afterglows. By estimating the jet opening angle with a jet-like break time tj in late multi-wavelength light curves, Ghirlanda et al. (2004a) derived a tight correlation between geometrically corrected jet energy \n\n\n\n\n\n and the peak energy \n\n\n\n\n\n of \n\n\n\n\n\n spectrum in the burst frame, i.e., \n\n\n\n\n\n. The \n\n\n\n\n\n value inferred from the Ghirlanda relation is 46 keV for GRB 140629A, which is definitely inconsistent with the data, i.e., \n\n\n\n\n\n. Liang & Zhang (2005) derived an empirical relation between \n\n\n\n\n\n, \n\n\n\n\n\n, and the jet break time (\n\n\n\n\n\n) in the burst frame, i.e., \n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\nBased on this relation, an isotropic energy \n\n\n\n\n\n erg is obtained, which is larger than that observed by more than one order of magnitude. These results suggest that GRB 140629A does not follow these two relations (Ghirlanda et al. 2004a; Liang & Zhang 2005), although both tight correlations have been used for measuring the cosmological parameters with GRBs (e.g., Dai et al. 2004; Ghirlanda et al. 2004b; Liang & Zhang 2005; Wang et al. 2015a). Note that the observed jet break time of GRB 140629A is much earlier, hence the inferred θj is much lower than those of the GRBs used to derive these relations (e.g., Frail et al. 2001; Bloom et al. 2003). It is unclear whether the violation of GRB 140629A is due to the selection effect or other physical reasons. For example, two-component jet models composed of a narrow and a wide component have been proposed to explain the data of some GRBs (e.g., Huang et al. 2004; Racusin et al. 2008). In these cases, the high-energy emission was proposed to be emitted by the narrow jet. However, one cannot exclude the possibility that the observed gamma-ray energy would be dominated by the wide jet component under certain conditions. Meanwhile, the early break time for GRB 140629A is likely due to the effect of the narrow jet component but not the wide one. If this is the case, the inconsistency between the jet energy and the opening angle would result in this violation of GRB 140629A. Liang et al. (2015) discovered a tight empirical correlation between Liso, \n\n\n\n\n\n, and Γ0 to reveal the direct connection between the gamma-ray and afterglows,\n7\n\n\n\n\n\nBased on the equation above, we get \n\n\n\n\n\n for GRB 140629A, where the error is calculated from the uncertainties in \n\n\n\n\n\n and Γ0 only. The derived \n\n\n\n\n\n is well consistent with the observed one, \n\n\n\n\n\n erg s−1, as shown in Figure 6. Note that the initial Lorentz factor of the ejecta Γ0 is sensitive to the deceleration time (the peak time of the onset bump), but not strongly related to the jet break time. The onset of the afterglow bump is usually bright (Liang et al. 2010, 2013; Li et al. 2012; Wang et al. 2013), and it is easier to identify than the jet break time from an observed light curve.10\n\n10\nThe jet break is usually detected in late optical afterglow light curves. It is dim and also contaminated by emission from the host galaxy and\/or associated supernovae (e.g., Li et al. 2012). This is also an issue in identifying an observed jet break as the narrow or the wide component in the case of a two-component jet.\n The consistency of GRB 140629A with \n\n\n\n\n\n suggests that this relation is more robust than the Ghirlanda or Liang–Zhang relations, since it is not sensitive to the jet opening angle θj.","Citation Text":["Ghirlanda et al. 2004a"],"Citation Start End":[[1227,1249]]} {"Identifier":"2018ApJ...860....8X__Ghirlanda_et_al._2004a_Instance_1","Paragraph":"For GRB 140629A, our analysis suggests that the optical and X-ray afterglows are from a narrow jet (\n\n\n\n\n\n rad) with a low B \n\n\n\n\n\n in a dense medium (n = 60 cm−3). In addition, the radiation efficiency of GRB 140629A is extremely low. We test whether or not it satisfies various empirical relations reported in the literature derived from observations of the prompt gamma-ray phase and the multi-wavelength afterglows. By estimating the jet opening angle with a jet-like break time tj in late multi-wavelength light curves, Ghirlanda et al. (2004a) derived a tight correlation between geometrically corrected jet energy \n\n\n\n\n\n and the peak energy \n\n\n\n\n\n of \n\n\n\n\n\n spectrum in the burst frame, i.e., \n\n\n\n\n\n. The \n\n\n\n\n\n value inferred from the Ghirlanda relation is 46 keV for GRB 140629A, which is definitely inconsistent with the data, i.e., \n\n\n\n\n\n. Liang & Zhang (2005) derived an empirical relation between \n\n\n\n\n\n, \n\n\n\n\n\n, and the jet break time (\n\n\n\n\n\n) in the burst frame, i.e., \n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\n\/\n\n\n\n\n\nBased on this relation, an isotropic energy \n\n\n\n\n\n erg is obtained, which is larger than that observed by more than one order of magnitude. These results suggest that GRB 140629A does not follow these two relations (Ghirlanda et al. 2004a; Liang & Zhang 2005), although both tight correlations have been used for measuring the cosmological parameters with GRBs (e.g., Dai et al. 2004; Ghirlanda et al. 2004b; Liang & Zhang 2005; Wang et al. 2015a). Note that the observed jet break time of GRB 140629A is much earlier, hence the inferred θj is much lower than those of the GRBs used to derive these relations (e.g., Frail et al. 2001; Bloom et al. 2003). It is unclear whether the violation of GRB 140629A is due to the selection effect or other physical reasons. For example, two-component jet models composed of a narrow and a wide component have been proposed to explain the data of some GRBs (e.g., Huang et al. 2004; Racusin et al. 2008). In these cases, the high-energy emission was proposed to be emitted by the narrow jet. However, one cannot exclude the possibility that the observed gamma-ray energy would be dominated by the wide jet component under certain conditions. Meanwhile, the early break time for GRB 140629A is likely due to the effect of the narrow jet component but not the wide one. If this is the case, the inconsistency between the jet energy and the opening angle would result in this violation of GRB 140629A. Liang et al. (2015) discovered a tight empirical correlation between Liso, \n\n\n\n\n\n, and Γ0 to reveal the direct connection between the gamma-ray and afterglows,\n7\n\n\n\n\n\nBased on the equation above, we get \n\n\n\n\n\n for GRB 140629A, where the error is calculated from the uncertainties in \n\n\n\n\n\n and Γ0 only. The derived \n\n\n\n\n\n is well consistent with the observed one, \n\n\n\n\n\n erg s−1, as shown in Figure 6. Note that the initial Lorentz factor of the ejecta Γ0 is sensitive to the deceleration time (the peak time of the onset bump), but not strongly related to the jet break time. The onset of the afterglow bump is usually bright (Liang et al. 2010, 2013; Li et al. 2012; Wang et al. 2013), and it is easier to identify than the jet break time from an observed light curve.10\n\n10\nThe jet break is usually detected in late optical afterglow light curves. It is dim and also contaminated by emission from the host galaxy and\/or associated supernovae (e.g., Li et al. 2012). This is also an issue in identifying an observed jet break as the narrow or the wide component in the case of a two-component jet.\n The consistency of GRB 140629A with \n\n\n\n\n\n suggests that this relation is more robust than the Ghirlanda or Liang–Zhang relations, since it is not sensitive to the jet opening angle θj.","Citation Text":["Ghirlanda et al. (2004a)"],"Citation Start End":[[525,549]]} {"Identifier":"2021ApJ...912...11D__Sell_et_al._2014_Instance_5","Paragraph":"None of the galaxies in this paper would be classified as an AGN on the basis of WISE mid-IR colors; they do not meet the \n\n\n\n\n\n (Vega) threshold from Stern et al. (2012) or the reliable AGN criteria from Assef et al. (2013). There are two galaxies with weak X-ray detections (J1506+5402 and J1613+2834, four X-ray counts each) from Sell et al. (2014) that indicate \n\n\n\n\n\n erg s−1 and four galaxies with X-ray upper limits (J0826+4305, J0944+0930, J1558+3957, J2140+1209) that imply \n\n\n\n\n\n erg s−1. All of these galaxies are consistent with the relationship between X-ray luminosity and mid-IR luminosity for starburst galaxies (Asmus et al. 2011; Mineo et al. 2014; Sell et al. 2014). One of the galaxies with a weak X-ray detection (J1506+5402) also has a clear detection of [Ne v] \n\n\n\n\n\n and an emission-line ratio \n\n\n\n\n\n, which is the highest ratio in the sample and consistent with a composite Baldwin, Phillips, and Terlevich (BPT) classification (Baldwin et al. 1981; Kewley et al. 2001; Kauffmann et al. 2003; Sell et al. 2014). These [Ne v] and [O iii] emission lines could be produced either by an extreme (\n\n\n\n\n\n Myr) starburst or an AGN that contributes \n\n\n\n\n\n% of the mid-IR continuum (Diamond-Stanic et al. 2012; Geach et al. 2013; Sell et al. 2014). The galaxy with the slowest outflow velocity in the sample (J2140+1209) has a weak broad Mg ii line, which is a clear indication of a type 1 AGN component, and spectral modeling suggests a \n\n\n\n\n\n% AGN continuum contribution at \n\n\n\n\n\n (Sell et al. 2014); the other 11\/12 galaxies show no evidence for any AGN continuum contributions at near-UV or optical wavelengths on the basis of high signal-to-noise spectroscopy (as described above and shown in Figure 1, which we describe below). In summary, there is some evidence for AGN activity in several of these 12 galaxies, but in all cases, the upper limits on the AGN emission indicate that it contributes a small fraction of the galaxy’s bolometric luminosity.","Citation Text":["Sell et al. 2014"],"Citation Start End":[[1500,1516]]} {"Identifier":"2021ApJ...912...11D__Sell_et_al._2014_Instance_4","Paragraph":"None of the galaxies in this paper would be classified as an AGN on the basis of WISE mid-IR colors; they do not meet the \n\n\n\n\n\n (Vega) threshold from Stern et al. (2012) or the reliable AGN criteria from Assef et al. (2013). There are two galaxies with weak X-ray detections (J1506+5402 and J1613+2834, four X-ray counts each) from Sell et al. (2014) that indicate \n\n\n\n\n\n erg s−1 and four galaxies with X-ray upper limits (J0826+4305, J0944+0930, J1558+3957, J2140+1209) that imply \n\n\n\n\n\n erg s−1. All of these galaxies are consistent with the relationship between X-ray luminosity and mid-IR luminosity for starburst galaxies (Asmus et al. 2011; Mineo et al. 2014; Sell et al. 2014). One of the galaxies with a weak X-ray detection (J1506+5402) also has a clear detection of [Ne v] \n\n\n\n\n\n and an emission-line ratio \n\n\n\n\n\n, which is the highest ratio in the sample and consistent with a composite Baldwin, Phillips, and Terlevich (BPT) classification (Baldwin et al. 1981; Kewley et al. 2001; Kauffmann et al. 2003; Sell et al. 2014). These [Ne v] and [O iii] emission lines could be produced either by an extreme (\n\n\n\n\n\n Myr) starburst or an AGN that contributes \n\n\n\n\n\n% of the mid-IR continuum (Diamond-Stanic et al. 2012; Geach et al. 2013; Sell et al. 2014). The galaxy with the slowest outflow velocity in the sample (J2140+1209) has a weak broad Mg ii line, which is a clear indication of a type 1 AGN component, and spectral modeling suggests a \n\n\n\n\n\n% AGN continuum contribution at \n\n\n\n\n\n (Sell et al. 2014); the other 11\/12 galaxies show no evidence for any AGN continuum contributions at near-UV or optical wavelengths on the basis of high signal-to-noise spectroscopy (as described above and shown in Figure 1, which we describe below). In summary, there is some evidence for AGN activity in several of these 12 galaxies, but in all cases, the upper limits on the AGN emission indicate that it contributes a small fraction of the galaxy’s bolometric luminosity.","Citation Text":["Sell et al. 2014"],"Citation Start End":[[1246,1262]]} {"Identifier":"2021ApJ...912...11D__Sell_et_al._2014_Instance_3","Paragraph":"None of the galaxies in this paper would be classified as an AGN on the basis of WISE mid-IR colors; they do not meet the \n\n\n\n\n\n (Vega) threshold from Stern et al. (2012) or the reliable AGN criteria from Assef et al. (2013). There are two galaxies with weak X-ray detections (J1506+5402 and J1613+2834, four X-ray counts each) from Sell et al. (2014) that indicate \n\n\n\n\n\n erg s−1 and four galaxies with X-ray upper limits (J0826+4305, J0944+0930, J1558+3957, J2140+1209) that imply \n\n\n\n\n\n erg s−1. All of these galaxies are consistent with the relationship between X-ray luminosity and mid-IR luminosity for starburst galaxies (Asmus et al. 2011; Mineo et al. 2014; Sell et al. 2014). One of the galaxies with a weak X-ray detection (J1506+5402) also has a clear detection of [Ne v] \n\n\n\n\n\n and an emission-line ratio \n\n\n\n\n\n, which is the highest ratio in the sample and consistent with a composite Baldwin, Phillips, and Terlevich (BPT) classification (Baldwin et al. 1981; Kewley et al. 2001; Kauffmann et al. 2003; Sell et al. 2014). These [Ne v] and [O iii] emission lines could be produced either by an extreme (\n\n\n\n\n\n Myr) starburst or an AGN that contributes \n\n\n\n\n\n% of the mid-IR continuum (Diamond-Stanic et al. 2012; Geach et al. 2013; Sell et al. 2014). The galaxy with the slowest outflow velocity in the sample (J2140+1209) has a weak broad Mg ii line, which is a clear indication of a type 1 AGN component, and spectral modeling suggests a \n\n\n\n\n\n% AGN continuum contribution at \n\n\n\n\n\n (Sell et al. 2014); the other 11\/12 galaxies show no evidence for any AGN continuum contributions at near-UV or optical wavelengths on the basis of high signal-to-noise spectroscopy (as described above and shown in Figure 1, which we describe below). In summary, there is some evidence for AGN activity in several of these 12 galaxies, but in all cases, the upper limits on the AGN emission indicate that it contributes a small fraction of the galaxy’s bolometric luminosity.","Citation Text":["Sell et al. 2014"],"Citation Start End":[[1018,1034]]} {"Identifier":"2021ApJ...912...11D__Sell_et_al._2014_Instance_1","Paragraph":"None of the galaxies in this paper would be classified as an AGN on the basis of WISE mid-IR colors; they do not meet the \n\n\n\n\n\n (Vega) threshold from Stern et al. (2012) or the reliable AGN criteria from Assef et al. (2013). There are two galaxies with weak X-ray detections (J1506+5402 and J1613+2834, four X-ray counts each) from Sell et al. (2014) that indicate \n\n\n\n\n\n erg s−1 and four galaxies with X-ray upper limits (J0826+4305, J0944+0930, J1558+3957, J2140+1209) that imply \n\n\n\n\n\n erg s−1. All of these galaxies are consistent with the relationship between X-ray luminosity and mid-IR luminosity for starburst galaxies (Asmus et al. 2011; Mineo et al. 2014; Sell et al. 2014). One of the galaxies with a weak X-ray detection (J1506+5402) also has a clear detection of [Ne v] \n\n\n\n\n\n and an emission-line ratio \n\n\n\n\n\n, which is the highest ratio in the sample and consistent with a composite Baldwin, Phillips, and Terlevich (BPT) classification (Baldwin et al. 1981; Kewley et al. 2001; Kauffmann et al. 2003; Sell et al. 2014). These [Ne v] and [O iii] emission lines could be produced either by an extreme (\n\n\n\n\n\n Myr) starburst or an AGN that contributes \n\n\n\n\n\n% of the mid-IR continuum (Diamond-Stanic et al. 2012; Geach et al. 2013; Sell et al. 2014). The galaxy with the slowest outflow velocity in the sample (J2140+1209) has a weak broad Mg ii line, which is a clear indication of a type 1 AGN component, and spectral modeling suggests a \n\n\n\n\n\n% AGN continuum contribution at \n\n\n\n\n\n (Sell et al. 2014); the other 11\/12 galaxies show no evidence for any AGN continuum contributions at near-UV or optical wavelengths on the basis of high signal-to-noise spectroscopy (as described above and shown in Figure 1, which we describe below). In summary, there is some evidence for AGN activity in several of these 12 galaxies, but in all cases, the upper limits on the AGN emission indicate that it contributes a small fraction of the galaxy’s bolometric luminosity.","Citation Text":["Sell et al. (2014)"],"Citation Start End":[[333,351]]} {"Identifier":"2021ApJ...912...11D__Sell_et_al._2014_Instance_2","Paragraph":"None of the galaxies in this paper would be classified as an AGN on the basis of WISE mid-IR colors; they do not meet the \n\n\n\n\n\n (Vega) threshold from Stern et al. (2012) or the reliable AGN criteria from Assef et al. (2013). There are two galaxies with weak X-ray detections (J1506+5402 and J1613+2834, four X-ray counts each) from Sell et al. (2014) that indicate \n\n\n\n\n\n erg s−1 and four galaxies with X-ray upper limits (J0826+4305, J0944+0930, J1558+3957, J2140+1209) that imply \n\n\n\n\n\n erg s−1. All of these galaxies are consistent with the relationship between X-ray luminosity and mid-IR luminosity for starburst galaxies (Asmus et al. 2011; Mineo et al. 2014; Sell et al. 2014). One of the galaxies with a weak X-ray detection (J1506+5402) also has a clear detection of [Ne v] \n\n\n\n\n\n and an emission-line ratio \n\n\n\n\n\n, which is the highest ratio in the sample and consistent with a composite Baldwin, Phillips, and Terlevich (BPT) classification (Baldwin et al. 1981; Kewley et al. 2001; Kauffmann et al. 2003; Sell et al. 2014). These [Ne v] and [O iii] emission lines could be produced either by an extreme (\n\n\n\n\n\n Myr) starburst or an AGN that contributes \n\n\n\n\n\n% of the mid-IR continuum (Diamond-Stanic et al. 2012; Geach et al. 2013; Sell et al. 2014). The galaxy with the slowest outflow velocity in the sample (J2140+1209) has a weak broad Mg ii line, which is a clear indication of a type 1 AGN component, and spectral modeling suggests a \n\n\n\n\n\n% AGN continuum contribution at \n\n\n\n\n\n (Sell et al. 2014); the other 11\/12 galaxies show no evidence for any AGN continuum contributions at near-UV or optical wavelengths on the basis of high signal-to-noise spectroscopy (as described above and shown in Figure 1, which we describe below). In summary, there is some evidence for AGN activity in several of these 12 galaxies, but in all cases, the upper limits on the AGN emission indicate that it contributes a small fraction of the galaxy’s bolometric luminosity.","Citation Text":["Sell et al. 2014"],"Citation Start End":[[667,683]]} {"Identifier":"2020MNRAS.494.2440A__Piso_&_Youdin_2014_Instance_1","Paragraph":"Equation (25) shows that entropy advection can easily result in tens of per cent increase in the outer boundary temperature, and possibly substantially more depending on the depth to which the flow penetrates and whether the Bondi radius is larger than the Hill radius. How will this impact the cooling luminosity? We can estimate the effect on the luminosity if we assume that the radiative zone is isothermal (which applies only to low-metallicity envelopes), so that the temperature at the radiative–convective boundary (RCB) is the same as the outer boundary temperature, TRCB = Tadv. The luminosity, set at the RCB, is\n(26)$$\\begin{eqnarray*}\r\nL\\approx {64\\pi GM_\\mathrm{ p}\\sigma T_{\\rm RCB}^4 \\nabla _{\\rm ad}\\over 3\\kappa P_{\\rm RCB}}\\propto {T_{\\rm RCB}^4\\over \\kappa P_{\\rm RCB}}\r\n\\end{eqnarray*}$$(Arras & Bildsten 2006; Piso & Youdin 2014) (again we will neglect the self-gravity of the envelope). For a power-law dependence of opacity κ ∝ ρaTb ∝ PaTb − a, we find that for a fixed internal entropy so that $P_{\\rm RCB}\\propto T_{\\rm RCB}^{\\gamma \/(\\gamma -1)}$, the luminosity varies with RCB temperature as\n(27)$$\\begin{eqnarray*}\r\n{\\mathrm{ d}\\ln L\\over \\mathrm{ d}\\ln T_{\\rm RCB}} = 4 - b+a - (1+a){\\gamma \\over \\gamma -1}.\r\n\\end{eqnarray*}$$Taking the values a = 2\/3 and b = 3 for molecular opacity from Bell & Lin (1994), we find that a change in RCB temperature ΔTRCB leads to a change in luminosity\n(28)$$\\begin{eqnarray*}\r\n{\\Delta L\\over L} &\\approx & -4 {\\Delta T_\\mathrm{RCB}\\over T_\\mathrm{RCB}}\\approx -4{T_\\mathrm{adv}-T_\\mathrm{ d}\\over T_\\mathrm{ d}}\\nonumber \\\\\r\n&=& -{8\\over 5} \\left({R_\\mathrm{ B}\\over R_{\\rm out}}\\right) \\left[{R_{\\rm out}\\over R_{\\rm adv}}-1\\right].\r\n\\end{eqnarray*}$$A hotter outer boundary leads to a lower luminosity. For Radv\/Rout = 0.3 (0.1) and assuming Rout = RB, the predicted decrease in luminosity is a factor of ≈4 (≈14). For dust opacity, Bell & Lin (1994) give a = 0 and b = 1\/2 (metal grains) or b = 2 (ice grains). In this case, dln L\/dln TRCB = (1\/2) − b, so the change in luminosity will be smaller than for molecular opacity.","Citation Text":["Piso & Youdin 2014"],"Citation Start End":[[832,850]]} {"Identifier":"2022ApJ...934...85A__Salpeter_1955_Instance_1","Paragraph":"Next, we try to convert the Galactic SN rate into a constraint on the Galactic SFR. According to Horiuchi et al. (2011) and Botticella et al. (2012), a cosmological SN rate is linked to the cosmological SFR as\n3\n\n\n\nRSN(z)=∫mlSNmuSNϕIMF(m)dm∫mlmumϕIMF(m)dmψSFR(z)≡kSNψSFR(z),\n\nwhere \n\n\n\nRSN(z)\n\n is the SN rate, ψ\nSFR(z) is the SFR as a function of redshift (z), ϕ\nIMF is the initial mass function (IMF), m is the mass of a star, (m\n\nl\n–m\n\nu\n) is the mass range of IMF, (\n\n\n\nmlSN\n\n–\n\n\n\nmuSN\n\n) is the mass range of SN stars, and \n\n\n\nkSN\n\n is the scaling factor between \n\n\n\nRSN\n\n and ψ\nSFR by the number fraction of stars per unit mass. We apply this relationship for the Galactic SN rate and averaged Galactic SFR; therefore, \n\n\n\nRSNgal=kSNψSFRgal\n\n. We show the constraint on \n\n\n\nψSFRgal\n\n and \n\n\n\nkSN\n\n with 90% CL as shown in Figure 4. The yellow vertical band is an expected range of \n\n\n\nkSN\n\n = (0.0068–0.0088)\n\n\n\nM⊙−1\n\n assuming the (modified) Salpeter-type IMF (Salpeter 1955; Horiuchi et al. 2011; Madau & Dickinson 2014), which contains uncertainties from astronomical observations and models. The lowest value of \n\n\n\nkSN\n\n is calculated from the IMF with a power index of the mass γ = −2.35 in the mass range of 0.1–100 M\n⊙. On the other hand, the highest value of \n\n\n\nkSN\n\n is obtained by combining the IMF with γ = −1.5 in the mass range of 0.1–0.5 M\n⊙ and the one with γ = −2.35 in the mass range of 0.5–100 M\n⊙. In either case, the mass range of SN stars is set in 8–40 M\n⊙. The colored horizontal lines and bands correspond to an allowed \n\n\n\nψSFRgal\n\n range reproduced from the astronomical observation to be (1–2) M\n⊙ yr−1 (Murray & Rahman 2009; Robitaille & Whitney 2010; Chomiuk & Povich 2011; Davies et al. 2011; Licquia & Newman 2015). Our result thus provides the upper limit on the SFR as \n\n\n\nψSFRgal\n\n (17.5–22.7) M\n⊙ yr−1 with 90% CL assuming the Salpeter-type IMF within our Galaxy. This result disfavors a large SFR in our Galaxy and is consistent with the constraints from the astronomical observations.","Citation Text":["Salpeter 1955"],"Citation Start End":[[968,981]]} {"Identifier":"2022ApJ...927..237I__Ding_et_al._2020_Instance_1","Paragraph":"The empirical relation between the mass of SMBHs and the properties of their host galaxies is considered to be one of the most important outcomes caused by their coevolution over the cosmic timescale (e.g., Magorrian et al. 1998; Ferrarese & Merritt 2000; Kormendy & Ho 2013). Theoretical models for explaining the tight correlations have been proposed, but the origin is still unclear. To understand the nature of these correlations, it is critically important to study them beyond the local universe, characterizing how and when the relations have been established and evolved until now. So far, a large number of observational studies have extensively investigated the redshift dependence of the BH-to-bulge mass ratio of M\n•\/M\n⋆ and overall suggested its positive redshift dependence, i.e., the ratio increases with redshift (Bennert et al. 2011; Schramm & Silverman 2013; Ding et al. 2020). Beyond z ∼ 6, the Atacama Large Millimeter\/submillimeter Array (ALMA) is a powerful tool to measure the dynamical mass of gas in quasar host galaxies and allows us to explore the early stage of the BH\/galaxy correlation (e.g., Wang et al. 2010, 2013; Venemans et al. 2017). In addition, observations with the Subaru HSC provide low-luminosity and less-massive BH samples, which are unique populations to determine the M\n•\/M\n⋆ ratio at z > 6 (Izumi et al. 2019, 2021). Figure 11 shows the distribution of z > 6 quasars compiled in Izumi et al. (2021), together with those in the local universe (Kormendy & Ho 2013). First, the brightest z > 6 quasars with M\n1450 −25 mag tend to have M\n•\/M\n⋆ ratios higher than those seen in the local universe. Namely, the mass ratio for those brightest objects is boosted by a factor of ∼10 (blue dashed line; Pensabene et al. 2020). On the other hand, the fainter quasars with M\n1450 >−25 mag appear to follow the local relation, although those BHs are considered to grow at rates of ≳ 0.05 SFR and will be overmassive at lower redshifts.\n15\n\n\n15\nIn this paper, overmassive BHs are referred to as a BH population with a BH-to-galaxy mass ratio higher than that observed in the local universe; \n\n\n\nM•\/M⋆≳4.9−0.5+0.6×10−3\n\n (Kormendy & Ho 2013). We employ this terminology to clearly contrast the difference between the overmassive and undermassive BH population with respect to the local value (see Figure 11). Note that a previous study by Agarwal et al. (2013) used a term of “obese BH,” which refers to a BH population dominating over the stellar mass of its host galaxy at least in the initial growing stage (i.e., M\n•\/M\n⋆ > 1). We note that for all of the z > 6 samples, the values of the x-axis are not the bulge mass of their host galaxies but the dynamical mass measured by [C ii] 158 μm lines. In general, the dynamical mass is considered to be higher than the true bulge mass. With a high-resolution ALMA observation, Izumi et al. (2021) found that the gas dynamics of the core component of a low-luminosity quasar at z = 7.07 (HSC J1243+0100) is governed by rotation associated with a compact bulge and estimated its mass as ∼50% of the [C ii]-based dynamical mass. Therefore, the correlation at z > 6 might be shifted to the left if the conversion factor from the dynamical mass to the bulge mass is taken into account.","Citation Text":["Ding et al. 2020"],"Citation Start End":[[877,893]]}