adsabs/AstroCLIMB huggingface dataset:
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: Strain surface plots and entropy slices for model s40o1 during the accretion phase. The x and y axes form the equator of the supernova; the z-axis indicates the axis of rotation. For the top two panels, the distance from the origin to a point on the green surface represents the detected h + along that direction. The bottom two panels are entropy slices, with overlaid velocity profiles (arrows). A clearer 3D picture of the dynamics can be seen in Figure 5. (a) Strain surface plot for h + during the accretion phase (∼285 ms pb). This rotating, four-lobed structure persists for the majority of the accretion phase, producing the largest GW amplitudes along the axis of rotation. (b) Strain surface plot for a rigid, solid-body ellipsoid. Data taken from simulation outputs motivate toy model parameters of mass 2.1 M ⊙, with principal axes c = 40 km, a = 62 km, b = 55 km, rotating with Ω = 1000 rad s−1, ﹩\dot{a}=\dot{b}=\dot{c}=0﹩ km s−1, replicating the strain surface during the accretion phase, seen in Figure 4(a). Once again, our choice of the solid-body approximation captures the morphology of the GW strain, while overestimating the magnitude. (c) Entropy slice through the CCSN pole for model s40o1 ∼285 ms pb. Arrows show the magnitude of the velocity in the y–z plane, and the solid black line is the density contour for the PNS surface of ρ = 1011 g cm−3. After the accretion of sufficient angular momentum from overlying material, the oblateness of the PNS increases. For scale, every centimeter on the page corresponds to 5.6 × 109 cm s−1. (d) Entropy slice through the equator from model s40o1 ∼285 ms after bounce. Accretion downflows striking the PNS surface cause slight deviations from axisymmetry (a circle in this slice). The oblateness of the PNS, deviation of axisymmetry in the azimuthal direction, and rotation motivate our choice for modeling the source of the GW emission as a rotating ellipsoid.
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: Strain surface plots and entropy slices for model s40o1 during the ringdown phase. The x and y axes form the equator of the supernova; the z-axis indicates the axis of rotation. For the top two panels, the distance from the origin to a point on the green surface represents the detected h + along that direction. The bottom two panels are entropy slices, with overlaid velocity profiles (arrows). (a) Strain surface plot for h + during ringdown. This rotating structure, which will modulate in scale for tens of milliseconds during ringdown, will give the largest GW amplitudes along the equator of the supernova. (b) Strain surface plot for a toy model of an elastic ellipsoid. Numbers taken from model s40o1 inform toy ellipsoid parameters of mass 1.3 M ⊙, with principal axes c = 77 km, a = 83 km, b = 81, rotating with Ω = 100 rad s−1, ﹩\dot{a}=\dot{b}=5000﹩ km s−1, ﹩\dot{c}=0﹩ km s−1, which replicates the strain surface for rotating ringdown seen in Figure 3(a). In particular, the rotating nonaxisymmetry (i.e., a ≠ b) of the ellipsoid contributes to the four-lobed structure. The changing principal axes (﹩\dot{a}\ne 0﹩, ﹩\dot{b}\ne 0﹩) contribute to the protruding GW surface along the equator. (c) Entropy slice through the pole from model s40o1 ∼13 ms after bounce shows a slightly oblate PNS surface. For scale, every centimeter on the page corresponds to 5.6 × 109 cm s−1. (d) Entropy slice through the equator from model s40o1 ∼13 ms after bounce display the PNS surface deviating from axisymmetry (a circle in this cross section) as convective instabilities within the PNS create asymmetries.
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: Strain surface plots and entropy slices for model s40o0 during the accretion phase. The x and y axes form the equator of the supernova; the z-axis indicates the pole. For the top two panels, the distance from the origin to a point on the green surface represents the detected h + along that direction. The bottom two panels are entropy slices, with overlaid velocity profiles (arrows). (a) Strain surface plot of h + for nonrotating model s40o0 during the accretion phase (∼230 ms pb). We attribute the skewed maximum GW amplitude (not aligned with the coordinate axes) with downflows perturbing the PNS at a misaligned angle. (b) Strain surface plot for nonrotating, tilted ellipsoid. Data taken from simulation outputs motivate toy model parameters of mass 2.1 M ⊙, with principal axes a = b = c = 45 km, nonrotating, ﹩\dot{a}=\dot{b}=0﹩ km s−1, and ﹩\dot{c}=50﹩ km s−1, tilted by π/4 radians, replicating the strain surface during the accretion phase, seen in Figure 6(a). Once again, our choice of the toy model approximation captures the morphology of the GW strain, while differing in the magnitude. (c) Entropy slice through the CCSN pole for model s40o0 ∼230 ms pb. Arrows show the magnitude of the velocity in the y–z plane, and the solid black line is the density contour for the PNS surface of ρ = 1011 g cm−3. The skewed angle of the postshock region is what motivates our choice for the tilted ellipsoid. For scale, every centimeter on the page corresponds to 5.6 × 109 cm s−1. (d) Entropy slice through the equator from model s40o0 ∼230 ms after bounce. Similar asymmetries to Figure 6(c) of the shock are visible when viewing the supernova equator.
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: These strain surface scatter plots, or S 3 plots, compile the direction of maximum GW emission (e.g., purple stars in Figures 2(a), 3(a), 4(a), and 6(a)) throughout the supernova evolution from simulation outputs. Brighter points correspond to later times. The x–y plane forms the equator of the supernova. The z-axis identifies the axis of rotation for rotating cases. (a) Dominant viewing angles of h + for s40o0. The distribution of dominant GW viewing angles remains nearly isotropic for the duration of the supernova evolution. (b) Dominant viewing angles of h + for s40o0.5. The dark (early time) points distributed along the equatorial plane are generated from the bounce signal and ringdown. The dominant signal direction then aligns with axis of rotation and finally relaxes to an isotropic distribution. (c) Dominant viewing angles of h + for the fast rotating model s40o1. The preferred GW direction is noticeably columnated and follows coherent paths that precess around the axis of rotation. (d) Same fast rotating model as in Figure 8(b), however, for the cross polarization h ×.
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: Strain surface plots of the tilted toy model ellipsoid from Section 4.5. h +, h ×, and ﹩\sqrt{{h}_{+}^{2}+{h}_{\times }^{2}}﹩ are shown from left to right. While similar to the dynamics of the bounce phase, we note different contributions to each polarization. Whereas a coordinate system aligned with the principal ellipsoid axis along c will only produce h + emission (Figure 2(b)), a differently oriented GW source will produce GW amplitudes with differing contributions in each polarization. When considering ﹩\sqrt{{h}_{+}^{2}+{h}_{\times }^{2}}﹩ on the right, the axisymmetric GW amplitudes are recovered along the axis tilted by π/4 from the z-axis. In short, two systems with similar dynamics will produce similar angular distributions of total amplitudes ﹩\sqrt{{h}_{+}^{2}+{h}_{\times }^{2}}﹩, but differing amounts in each polarization.
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: Magnitude of the spatial velocity—color values centered ∼3.9 × 109 cm s−1—near the PNS for model s40o1, taken ∼286 ms pb. The panel spans 200 km. The axis of rotation is aligned vertically with the page. The 3D structure more clearly displays the coherent flows around the PNS, whose oblateness can be seen by the inner contour, complementing the entropy slices seen in Figure 4.
Paper: Characterizing the Directionality of Gravitational Wave Emission from Matter Motions within Core-collapse Supernovae
Authors: Michael A. Pajkos, Steven J. VanCamp, Kuo-Chuan Pan, David Vartanyan, Nils Deppe, Sean M. Couch
Figure caption: Time domain waveforms (plus polarization) for s40o0 (top), s40o0.5 (middle), and s40o1 (bottom; Pan et al. 2021). The left (right) column corresponds to an observed h + when viewed along the equator (pole). While TDWFs are useful for analyzing GW emission throughout the supernova simulation, they are inherently limited to GW signals at a single, fixed viewing angle. This motivates the need for additional analysis methods that can identify a dominant viewing angle beyond the equator or pole and determine if this direction evolves in time. Note the different scales between each y-axis. Figure from Pajkos (2022).
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: Top: each panel gives ﹩{\rm{\Delta }}\mathrm{log}({\rm{O}}/{\rm{H}})﹩ as a function of log(SFR) for Z O3Hβ  (left), Z O3O2 (middle), and Z R23 (right). Individual HALO7D galaxies are given by blue points, while median ﹩{\rm{\Delta }}\mathrm{log}({\rm{O}}/{\rm{H}})﹩ is given by red diamonds for bins of log(SFR). Error bars give the standard deviation in each bin. Using Spearman rank correlation tests, we find weak but significant correlations between ﹩{\rm{\Delta }}\mathrm{log}({\rm{O}}/{\rm{H}})﹩ and the SFR, though the significance for R23 is marginal. The test parameters are shown in the bottom left of each panel. Middle: same as the top row, but ﹩{\rm{\Delta }}\mathrm{log}({\rm{O}}/{\rm{H}})﹩ is given as a function of sSFR, the SF per stellar mass. We test this to check whether the scatter dependence on SFR is not simply restating the stellar mass dependence. We once more find weak but significant negative correlations with O3Hβ- and O3O2-measured metallicities, but no significance with R23. The methodological dependence perhaps reflects the use of the Hβ line in both Z and SFR measurements for O3Hβ and R23, but with O3O2, we measure significant correlations with both SFR and sSFR, indicating a weak tendency for more star-forming galaxies to exhibit lower Z. Bottom: ﹩{\rm{\Delta }}\mathrm{log}({\rm{O}}/{\rm{H}})﹩ is given as a function of ﹩{\rm{Log}}({{\rm{\Sigma }}}_{\mathrm{SFR}}﹩), the SF surface density, calculated from the half-light radii in kiloparsecs. We test this to check whether morphology helps SF relate to the metallicity scatter, e.g., by facilitating or inhibiting the expulsion of metal-enriched gas. As in the two previous cases, we measure a weak, marginal anticorrelation using O3Hβ, a significant anticorrelation with O3O2, and no detectable relation with R23.
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: HALO7D strong-emission line ratios as a function of stellar mass. In all panels, blue dots indicate individual HALO7D measurements, and cyan diamonds show the median HALO7D ratios in bins of stellar mass. Green squares denote z < 0.07 SDSS galaxies (Andrews & Martini 2013) corrected for diffuse ionized gas emission (Sanders et al. 2017). The top panel also gives the 90% SDSS population distribution within the shaded region. For comparison, composite spectra of z ∼ 2.3 and z ∼ 3.3 star-forming galaxies from the MOSDEF survey (Sanders et al. 2021) are shown with magenta circles and red triangles, respectively. In the top panel, the red curve indicates the diagnostic cutoff between SF galaxies below and AGN above (Juneau et al. 2014). The dashed vertical line separates the dwarf galaxies from the massive sample. In all three methods, the HALO7D medians for dwarf galaxies track the low-redshift composite measurements within the 1 standard deviation scatter, consistent with little evolution in the strong-line ratios of dwarf galaxies from z ∼ 1 to z = 0. (see Section 3.1)
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: The HALO7D MZRs. Each panel depicts an MZR determined with a different metallicity indicator. Clockwise from top left, they use O3Hβ, R23, Ne3O2, and O3O2. Individual HALO7D galaxies are shown as hollow black circles. The median HALO7D metallicity in bins of stellar mass is shown by the red diamonds, and the error bars give the standard deviation of metallicity in each mass bin. The HALO7D MZRs given by the median metallicities are consistent within the 1σ scatter with MZRs measured at redshifts near 0 (Tremonti et al. 2004; Andrews & Martini 2013) and those measured at comparable redshift using strong-line methods (Zahid et al. 2011; Guo et al. 2016a). This means we see a high-metallicity offset in comparison to the MZRs measured at higher redshift (e.g., Sanders et al. 2020), as well as those determined using only T  e -measured galaxies dependent on the [O III]λ4363 line. We also see some indication of higher scatter in metallicity among low-mass galaxies, which we explore in the subsequent sections.
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: Top: example spectra of three HALO7D dwarf galaxies with a range of line EWs. The blue solid line denotes the observed spectrum. The orange solid line shows the continuum estimate, and the green solid line the continuum-subtracted spectrum. Prominent emission lines are labeled and indicated by vertical-dashed lines. Black-dashed lines indicate strong and/or Balmer series emission lines. Green-dashed lines indicate typically fainter ionized metal lines, and blue-dashed lines show the locations of faint helium emission lines. The two magenta-dashed lines show the locations of the Ca H and K stellar absorption lines, though these features are not prominent in this spectrum, which has little stellar continuum due to its low stellar mass as well as a likely young stellar population. Bottom: an example composite spectrum for the lowest mass bin at 0.4 < z < 0.7, as described in Section 3.4. The inset on the right shows a zoom-in around the [O III]λ4363 line used for metallicity measurement via the T  e  method.
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: Left: the scatter in the MZR σ MZR in bins of stellar mass. We calculate σ MZR for each of the three strong-line metallicity methods, indicated by different shapes and colors of track. Right: the intrinsic σ MZR scatter, calculated by subtracting in quadrature the median measurement error in each bin from the measured scatter. The trend of increasing scatter remains after the removal of measurement error, indicating that a broader range of gas-phase metallicities is fundamentally related to lower stellar mass in a galaxy. Gray curves indicate comparison samples, which show similar overall trends and offsets of <0.05 dex for low-mass galaxies.
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: Left: the stellar mass vs. redshift distribution of the HALO7D galaxy sample. The vertical-dashed line separates the dwarf and massive galaxy populations, defined at ﹩\mathrm{log}({M}_{\star }/{M}_{\odot })=9.5﹩. The gray points and histograms indicate the overall sample of galaxies for which a good redshift fit was obtained from spectral features, as described in Section 2.2. The blue points and histograms denote the subsample of galaxies with a sufficient set of emission line detections needed to measure the gas-phase metallicity (Z) from one of the strong-line methods described in 3. This yields a metallicity sample of 583 galaxies, including 388 dwarf galaxies, with a redshift range of 0.3 < z < 0.9. At higher redshift, the [O III]4959,5007 doublet moves out of the detection range. Red stars indicate [O III]λ4363 detections, described in Section 3.3. Right: the same distribution, but showing the fraction of the overall HALO7D sample included in the metallicity sample as a function of redshift and mass. The metallicity success rate for dwarf galaxies is high (typically >75%) in the most populated bins. For further analysis of the overall HALO7D sample, see (Pharo et al. 2022).
Paper: Validating Posteriors Obtained by an Emulator When Jointly Fitting Mock Data of the Global 21 cm Signal and High-z Galaxy UV Luminosity Function
Authors: J. Dorigo Jones, D. Rapetti, J. Mirocha, J. J. Hibbard, J. O. Burns, N. Bassett
Figure caption: Marginalized 1D and 2D posterior distributions for eight astrophysical parameters in ARES when jointly fitting mock global 21 cm signal and UVLF data. All is the same as in Figures 3 and B1, except that the noise in the 21 cm data being fit is  σ  21 = 250 mK, and the axis ranges are zoomed out to show the full prior ranges.
Paper: Dwarf Galaxies Show Little ISM Evolution from z ∼ 1 to z ∼ 0: A Spectroscopic Study of Metallicity, Star Formation, and Electron Density
Authors: John Pharo, Yicheng Guo, Guillermo Barro Calvo, Teja Teppala, Fuyan Bian, Timothy Carleton, Sandra Faber, Puragra Guhathakurta, David C. Koo
Figure caption: The MZR using T  e -derived metallicity measurements. Individual HALO7D galaxies are shown as small green circles. Blue and red circles show the measurements from composite spectra of HALO7D galaxies in two redshift bins, with the points sized according to the number of spectra contributing to each composite. Blue and red triangles show O3Hβ-derived metallicities for the same stacks. In the left panel, we include for comparison a z ∼ 0 MZR from T  e  measurements of SDSS galaxies (Andrews & Martini 2013), T  e -derived metallicities from a small sample of z ∼ 0.8 galaxies (FIGS, Pharo et al. 2019), 1.3 < z < 2.3 stacks (Henry et al. 2021), and z ∼ 2.3 stacks (Sanders et al. 2021). In the right panel, we compare with strong-line calibrations in both HALO7D and from Guo et al. (2016a).
Paper: Particle-in-Cell Simulations of Sunward and Anti-sunward Whistler Waves in the Solar Wind
Authors: Ilya V. Kuzichev, Ivan Y. Vasko, Anton V. Artemyev, Stuart D. Bale, Forrest S. Mozer
Figure caption: The evolution of the velocity distribution function (VDF) of halo electrons in the simulation run with β  c  = 1, A  h =1.3, and u  c /v  A  = − 1.5, exhibiting the electron heat flux suppression of about 8% of the initial heat flux value q  e (0) (Figure 5): (a), (b) initial and saturated VDFs of halo electrons (log scale) and (c) the relative difference of these distributions, δVDF = VDFsat/VDFin − 1; (d) the linear density of the initial and saturated heat flux in the parallel velocity space, Q  h (v ∣∣) = 0.5∫v ∣∣ m  e   v  2 · f  h (v ∣∣, v ⊥)d 2 v ⊥, where f  h (v ∣∣, v ⊥) is the VDF of halo electrons, and (e) the difference δ Q  h (v ∥) of the initial and saturated heat flux densities (the heat flux density is in arbitrary units). The percentage values indicated in panel (e) correspond to the variation of partial heat fluxes, ﹩{\int }_{{v}_{| | }\lt 0}\delta {Q}_{h}{{dv}}_{| | }\approx -0.41\ {q}_{e}(0)﹩ and ﹩{\int }_{{v}_{| | }\gt 0}\delta {Q}_{h}{{dv}}_{| | }\approx 0.32\ {q}_{e}(0)﹩, in units of the initial electron heat flux value. The resonant electron velocities, v ∣∣ = (ω + − ω  c )/k + < 0 and v ∣∣ = (ω − − ω  c )/k − > 0, corresponding, respectively, to parallel and antiparallel whistler waves, are indicated in panel (c) by solid vertical lines.
Paper: Particle-in-Cell Simulations of Sunward and Anti-sunward Whistler Waves in the Solar Wind
Authors: Ilya V. Kuzichev, Ivan Y. Vasko, Anton V. Artemyev, Stuart D. Bale, Forrest S. Mozer
Figure caption: The results of linear stability analysis of a combined whistler heat flux and temperature anisotropy instability at fixed core electron beta and halo temperature anisotropy (β  c  = 1 and A  h  = 1.3) but various values of the electron heat flux set by core drift velocity u  c /v  A . Panels (a) and (b) present dispersion curves (ω/ω  ce  vs. kc/ω  pe ) and growth rates (γ/ω  ce  vs. kc/ω  pe ) of whistler waves propagating parallel (k > 0) and antiparallel (k < 0) to the electron heat flux, where ω  ce  and ω  pe  are, respectively, electron cyclotron and plasma frequencies. Panels (c)–(e) present the growth rate, frequency, and wavenumber of the fastest-growing parallel and antiparallel whistler waves at various values of core drift velocity u  c /v  A . The green bars in panels (c)–(e) indicate u  c /v  A  values used in simulation runs presented in Section 3.
Paper: Particle-in-Cell Simulations of Sunward and Anti-sunward Whistler Waves in the Solar Wind
Authors: Ilya V. Kuzichev, Ivan Y. Vasko, Anton V. Artemyev, Stuart D. Bale, Forrest S. Mozer
Figure caption: The temporal evolution of the electron heat flux in simulation runs performed at β  c  = 1 and A  h  = 1.3 but various values of core electron drift velocity u  c /v  A  (Section 3). The panel presents the relative electron heat flux variation in percent, ﹩\delta {q}_{e}=100 \% \cdot \left[\ {q}_{e}(t)/{q}_{e}(0)-1\right]﹩, where q  e (t) is the electron heat flux averaged over the simulation box.
Paper: Particle-in-Cell Simulations of Sunward and Anti-sunward Whistler Waves in the Solar Wind
Authors: Ilya V. Kuzichev, Ivan Y. Vasko, Anton V. Artemyev, Stuart D. Bale, Forrest S. Mozer
Figure caption: The results of simulation runs performed at β  c  = 1 and A  h  = 1.3 but various values of core electron drift velocity u  c /v  A  (Section 3). Panel (a) presents saturated amplitudes ﹩{B}_{w}^{+}/{B}_{0}﹩ and ﹩{B}_{w}^{-}/{B}_{0}﹩ of parallel and antiparallel whistler waves along with their initial linear growth rates γ +/ω  ce  and γ −/ω  ce  also shown in Figure 1. Panel (b) demonstrates that the ratios ﹩{B}_{w}^{+}/{B}_{w}^{-}﹩ and γ +/γ − are closely correlated, ﹩{B}_{w}^{+}/{B}_{w}^{-}\approx {({\gamma }_{+}/{\gamma }_{-})}^{0.73}﹩.