adsabs/AstroCLIMB huggingface dataset:
Paper: Comprehensive X-Ray Observations of the Exceptional Ultralong X-Ray and Gamma-Ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-Ray Afterglow Properties
Authors: Brendan O'Connor, Ramandeep Gill, James DeLaunay, Jeremy Hare, Dheeraj Pasham, Eric R. Coughlin, Ananya Bandopadhyay, Akash Anumarlapudi, Paz Beniamini, Jonathan Granot, Igor Andreoni, Jonathan Carney, Michael J. Moss, Ersin Göğüş, Jamie A. Kennea, Malte Busmann, Simone Dichiara, James Freeburn, Daniel Gruen, Xander J. Hall, Antonella Palmese, Tyler Parsotan, Samuele Ronchini, Aaron Tohuvavohu, Maia A. Williams
Figure caption: Top left: results of our temporal fit with the afterglow start time free. The fit includes all XRT and Chandra data. Top right: results of our temporal fit with the start time T0 fixed to GRB 250702D’s trigger time. Bottom left: the same as the top left but only including XRT data after 0.55 days. Bottom right: the same as the bottom right but only including XRT data after 0.55 days. The posterior distributions on T0 are also shown in Figure 1.
Paper: Turbulence-driven Anisotropic Acceleration of Energetic Electrons in Solar Wind Current Sheets
Authors: L. D. Wang, Y. Wang, F. S. Wei, X. S. Feng, B. Y. Wang, P. B. Zuo, Y. L. Chen, X. J. Xu, Z. L. Zhou
Figure caption: The normalized electron spectral index γnormal as a function of εe_normal (a)–(b), εc_normal (c)–(d), and εnormal (e)–(f) based on 103 events, shown for the parallel (left) and perpendicular (right) directions. Error bars represent the standard error.
Paper: Turbulence-driven Anisotropic Acceleration of Energetic Electrons in Solar Wind Current Sheets
Authors: L. D. Wang, Y. Wang, F. S. Wei, X. S. Feng, B. Y. Wang, P. B. Zuo, Y. L. Chen, X. J. Xu, Z. L. Zhou
Figure caption: Case studies of the relationship between the normalized spectral index and various turbulence metrics inside representative current sheets. The black triangles indicate the normalized spectral index at each native SST timestamp. (a) PVI and the perpendicular spectral index. (b) εe_normal and the perpendicular spectral index. (c) εc_normal and the parallel spectral index. (d) εnormal and the perpendicular spectral index.
Paper: Turbulence-driven Anisotropic Acceleration of Energetic Electrons in Solar Wind Current Sheets
Authors: L. D. Wang, Y. Wang, F. S. Wei, X. S. Feng, B. Y. Wang, P. B. Zuo, Y. L. Chen, X. J. Xu, Z. L. Zhou
Figure caption: The normalized electron spectral index γnormal as a function of PVI, based on 103 events, shown for the parallel (left) and perpendicular (right) directions. The different colors correspond to different time lags (τ) used for the PVI calculation, as indicated by the legend. Error bars represent the standard error.
Paper: Turbulence-driven Anisotropic Acceleration of Energetic Electrons in Solar Wind Current Sheets
Authors: L. D. Wang, Y. Wang, F. S. Wei, X. S. Feng, B. Y. Wang, P. B. Zuo, Y. L. Chen, X. J. Xu, Z. L. Zhou
Figure caption: The average normalized flux enhancement (dF) for energetic electrons within 103 current sheet events. Panels (a) and (b) show the enhancement in the parallel and perpendicular directions, respectively. The error bars represent the standard error.
Paper: Comprehensive X-Ray Observations of the Exceptional Ultralong X-Ray and Gamma-Ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-Ray Afterglow Properties
Authors: Brendan O'Connor, Ramandeep Gill, James DeLaunay, Jeremy Hare, Dheeraj Pasham, Eric R. Coughlin, Ananya Bandopadhyay, Akash Anumarlapudi, Paz Beniamini, Jonathan Granot, Igor Andreoni, Jonathan Carney, Michael J. Moss, Ersin Göğüş, Jamie A. Kennea, Malte Busmann, Simone Dichiara, James Freeburn, Daniel Gruen, Xander J. Hall, Antonella Palmese, Tyler Parsotan, Samuele Ronchini, Aaron Tohuvavohu, Maia A. Williams
Figure caption: Left: the peak timescale (source frame) for accretion onto a BH from a tidally disrupted WD, as a function of the mass of the WD. The different colors represent different BH masses, as shown in the legend. Right: fallback rate onto the BH from a hydrodynamical simulation of a 0.6M⊙ WD modeled as a 5/3 polytrope, being disrupted by a 4 × 103M⊙ (light blue curve) and 2 × 104M⊙ (dark blue curve) BH. The black dashed line shows a t−5/3 scaling, which is the expected late-time scaling of the fallback rate if the WD is completely tidally destroyed. The times are in the source frame.
Paper: Ringed versus Ringless Worlds: How Poynting–Robertson Drag Shapes Rings across the Solar System
Authors: Ryuki Hyodo, Shigeru Ida
Figure caption: Parameter space of the decay timescale as a function of the central body’s semimajor axis and ring particle radius (Equation (4)). The top and bottom panels correspond to cases with ρpar = 3.0 g cm−3 and ρpar = 1.0 g cm−3, corresponding to densities typical of rocky and icy ring particles, respectively. Regions with τdecay > 4 × 109 yr are shaded light blue, whereas those with τdecay < 4 × 109 yr are shaded light red. Contours indicate constant timescales of τdecay = 109, 108, 107, and 106 yr. Q = 1 is assumed. Vertical lines indicate the reference semimajor axes of selected planetary bodies.
Paper: Ringed versus Ringless Worlds: How Poynting–Robertson Drag Shapes Rings across the Solar System
Authors: Ryuki Hyodo, Shigeru Ida
Figure caption: Time evolution of the orbital distance of a particle around a central body, initially starting from apar = 5Rpla. For reference, apar ∼ 3Rpla is the Roche limit of Earth and Mars. The red, black, and blue curves correspond to a particle radius of rpar = 1 cm, 10 cm, and 1 m, respectively. Both the planetary obliquity and the particle’s orbital inclination are set to zero. In these calculations, the central body is assumed to be spherical. The calculations here include the perturbations from the planet’s shadow (the ϕ term given in Table 1).
Paper: Comprehensive X-Ray Observations of the Exceptional Ultralong X-Ray and Gamma-Ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-Ray Afterglow Properties
Authors: Brendan O'Connor, Ramandeep Gill, James DeLaunay, Jeremy Hare, Dheeraj Pasham, Eric R. Coughlin, Ananya Bandopadhyay, Akash Anumarlapudi, Paz Beniamini, Jonathan Granot, Igor Andreoni, Jonathan Carney, Michael J. Moss, Ersin Göğüş, Jamie A. Kennea, Malte Busmann, Simone Dichiara, James Freeburn, Daniel Gruen, Xander J. Hall, Antonella Palmese, Tyler Parsotan, Samuele Ronchini, Aaron Tohuvavohu, Maia A. Williams
Figure caption: The same as Figure 20 but now using the GBM “D” burst as T0.
Paper: Comprehensive X-Ray Observations of the Exceptional Ultralong X-Ray and Gamma-Ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-Ray Afterglow Properties
Authors: Brendan O'Connor, Ramandeep Gill, James DeLaunay, Jeremy Hare, Dheeraj Pasham, Eric R. Coughlin, Ananya Bandopadhyay, Akash Anumarlapudi, Paz Beniamini, Jonathan Granot, Igor Andreoni, Jonathan Carney, Michael J. Moss, Ersin Göğüş, Jamie A. Kennea, Malte Busmann, Simone Dichiara, James Freeburn, Daniel Gruen, Xander J. Hall, Antonella Palmese, Tyler Parsotan, Samuele Ronchini, Aaron Tohuvavohu, Maia A. Williams
Figure caption: Results of our temporal fit with a broken power law with the onset time T0 as a free parameter.
Paper: Comprehensive X-Ray Observations of the Exceptional Ultralong X-Ray and Gamma-Ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-Ray Afterglow Properties
Authors: Brendan O'Connor, Ramandeep Gill, James DeLaunay, Jeremy Hare, Dheeraj Pasham, Eric R. Coughlin, Ananya Bandopadhyay, Akash Anumarlapudi, Paz Beniamini, Jonathan Granot, Igor Andreoni, Jonathan Carney, Michael J. Moss, Ersin Göğüş, Jamie A. Kennea, Malte Busmann, Simone Dichiara, James Freeburn, Daniel Gruen, Xander J. Hall, Antonella Palmese, Tyler Parsotan, Samuele Ronchini, Aaron Tohuvavohu, Maia A. Williams
Figure caption: The background-subtracted 3–79 keV NuSTAR lightcurves for both FPMA and FPMB individually in 150 s bins. The background lightcurves for both FPMA and FPMB are also shown for comparison. The dashed black line shows the mean (background-subtracted) count rate in the observation (∼0.25 cts s−1). The bottom panel shows the residuals (for both FPMA and FPMB) with respect to the mean count rate, to underscore the source’s short-timescale variability.
Paper: Comprehensive X-Ray Observations of the Exceptional Ultralong X-Ray and Gamma-Ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-Ray Afterglow Properties
Authors: Brendan O'Connor, Ramandeep Gill, James DeLaunay, Jeremy Hare, Dheeraj Pasham, Eric R. Coughlin, Ananya Bandopadhyay, Akash Anumarlapudi, Paz Beniamini, Jonathan Granot, Igor Andreoni, Jonathan Carney, Michael J. Moss, Ersin Göğüş, Jamie A. Kennea, Malte Busmann, Simone Dichiara, James Freeburn, Daniel Gruen, Xander J. Hall, Antonella Palmese, Tyler Parsotan, Samuele Ronchini, Aaron Tohuvavohu, Maia A. Williams
Figure caption: The same as Figure 9 but now using GRB 250702D as the start time T0. The FS afterglow fit posterior distributions are shown in Figure 21, and the RS emission is now obtained with a different value of εB,RS = 2 × 10−4. The description of the data is broadly consistent with the fit in Figure 9. The lightcurves are obtained for the following model parameters that keep the X-ray afterglow emission below the flaring X-ray emission at early times: θj = 4 × 10−3 rad, Ek,iso = 4 × 1055 erg, Γ0 = 282, n0 = 1.9 at R0 = 1018 cm, p = 2.24, ϵe = 0.13, and ϵB = 10−4, k = 2.
Paper: Self-similar Cosmic-Ray Transport in High-resolution Magnetohydrodynamic Turbulence
Authors: Philipp Kempski, Drummond B. Fielding, Eliot Quataert, Robert J. Ewart, Philipp Grete, Matthew W. Kunz, Alexander A. Philippov, James Stone
Figure caption: PDFs of collision times calculated using the particles’ magnetic moments (see Figure 5). We bin ﹩{\mathrm{log}}({\mu }_{{\rm{M}}})﹩ in bins of width 1/2 and define τμ as the time a particle spends in the same bin. P(τμ) shows clear power-law behavior, qualitatively similar to the P(τz) and P(τb) PDFs in Figure 6. This suggests that the power laws in P(τz) and P(τb) are likely not due to magnetic mirroring, which conserves μM.
Paper: Only Nitrogen-enhanced Galaxies Have Detectable Ultraviolet Nitrogen Emission Lines at High Redshift
Authors: Peixin Zhu, Lisa J. Kewley, Tiger Yu-Yang Hsiao, James Trussler
Figure caption: Detection limits of JWST observations for UV nitrogen emission lines N III] and N IV]. The gray dashed and dotted lines indicate the 3σ detection thresholds for the CEERS survey (exposure time: 3.1 ks) and the JADES Deep survey (maximum exposure time: 27.7 hr), respectively, assuming a rest-frame continuum level of ∼10−19 erg cm−2 s−1 Å−1. H II region models at ﹩\mathrm{log}(P/k)=9.2﹩ are shown in red (N-normal) and orange (N-enhanced), while AGN photoionization models at the same gas pressure are shown in blue (N-normal) and deep sky blue (N-enhanced). Solid and dashed lines represent AGN models with ﹩\mathrm{log}({E}_{\,\rm{peak}\,}/{\rm{keV}})=-2.0﹩ and −1.75, respectively. Each model grid consists of constant metallicity lines (﹩12+\mathrm{log}({\rm{O}}/{\rm{H}})=7.30,7.70,8.00,8.28,8.43﹩ for AGN; 7.15, 7.75, 8.15, 8.43 for H II) and constant ionization parameter lines (spanning ﹩\mathrm{log}(U)=-3.0﹩ to −0.5 for AGN and ﹩\mathrm{log}(U)=-4.0﹩ to −0.5 for H II, in steps of 0.5 dex). Large colored squares represent the z > 5 “N-enhanced” galaxy sample compiled in P. Zhu et al. (2025a), and open gray squares represent archival >3σ N III] and N IV] detections collected from the DJA. Black arrows in the upper-right corner of each panel indicate the effect of AV = 5.0 mag dust extinction on the UV observations derived from the extinction curve in J. A. Cardelli et al. (1989).
Paper: Only Nitrogen-enhanced Galaxies Have Detectable Ultraviolet Nitrogen Emission Lines at High Redshift
Authors: Peixin Zhu, Lisa J. Kewley, Tiger Yu-Yang Hsiao, James Trussler
Figure caption: Detection Limits of JWST observations for the UV emission lines He II and O III]. CLASSY galaxies with >3σ O III] and He II detections are included for comparison and shown as red circles. Model grid parameter ranges and symbols follow those in Figure 1.
Paper: Only Nitrogen-enhanced Galaxies Have Detectable Ultraviolet Nitrogen Emission Lines at High Redshift
Authors: Peixin Zhu, Lisa J. Kewley, Tiger Yu-Yang Hsiao, James Trussler
Figure caption: Detection limit on N III] and N IV] emission lines for JWST observations with different exposure times. The green dashed and dotted lines represent the 3σ detection limit of a 40 hr survey and a 500 hr survey using NIRSpec PRISM, respectively, for galaxies with rest-frame continuum level at ∼10−19 erg cm−2 s−1 Å−1. Model grid parameter ranges follow those in Figure 1.
Paper: Only Nitrogen-enhanced Galaxies Have Detectable Ultraviolet Nitrogen Emission Lines at High Redshift
Authors: Peixin Zhu, Lisa J. Kewley, Tiger Yu-Yang Hsiao, James Trussler
Figure caption: Detection Limits of JWST observations for the UV emission lines C III] and C IV. CLASSY galaxies with C III] and C IV detections are included for comparison and shown as red circles. Model grid parameter ranges and symbols follow those in Figure 1.
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Left panel: distribution of χeff for mutually aligned spin directions (maroon) and random spin directions (teal). Dotted lines indicate equal-mass (q = 1) and maximally spinning BBHs (χ1 = χ2 = 1), solid lines assume an extended mass ratio distribution and a spin magnitude distribution that peaks at lower values, which are consistent with previous GW detections (see Section 1). Black markers show three eccentric BBH merger candidates identified by N. Gupte et al. (2024; from bottom to top: GW200129, GW190701, and GW200208_22), and orange markers show four candidates identified by I. Romero-Shaw et al. (2022; from bottom to top: GW200208_22, GW190521, GW190620, and GW191109). The commonly identified candidate GW200208_22 is highlighted by a filled marker (I. Romero-Shaw et al. 2025). Right panel: sketch of uncorrelated (top) and mutually aligned black hole spins of eccentric mergers (bottom).
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Bayes factor distributions that compare the mutually aligned and uncorrelated models. The maroon histogram assumes GW detections of systems with mutually aligned spins and indicates the confidence for preferring the aligned model over the uncorrelated model. Conversely, the teal histogram assumes GW detections of systems with uncorrelated spins and indicates the confidence for preferring the uncorrelated spin model over the mutually aligned spin model. Thus, in either case, a large Bayes factor (﹩{\mathrm{log}}_{10}\,{ \mathcal B }\gtrsim 1.3﹩) indicates that we would correctly infer the spin properties of the underlying population. Solid and dashed vertical lines indicate the medians and 5th/95th percentiles of the distributions, respectively. We assume an eccentric BBH fraction of ξecc = 0.05, a measurement uncertainty for χeff of ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}=0.2﹩ for LVK O5 and A# and ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}=0.02﹩ for ET/CE, and vary between each panel the total number of detections between 2, 100 (LVK O5), 104 (A#), and 105 (ET/CE).
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Percentiles of the Bayes factor distributions that compare the uncorrelated model (teal) to a tilted model (maroon), where we allow the spins to be tilted with respect to one another by ﹩{{\rm{\min }}}({\hat{{\boldsymbol{\chi }}}}_{1}\cdot {\hat{{\boldsymbol{\chi }}}}_{2})﹩. We assume an eccentric BBH fraction of ξecc = 0.05 and a measurement uncertainty for χeff of ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}=0.2﹩ for LVK O5 and A# and ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}=0.02﹩ for ET/CE.
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Percentiles of the Bayes factor distributions as a function of the eccentric BBH fraction ξecc. We assume that χeff will be measured with an uncertainty of ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}=0.2﹩ for LVK O5 and A# and ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}=0.02﹩ for ET/CE. As in Figure 2, solid and dashed lines indicate the median and 5th/95th percentiles, respectively. The vertical yellow dotted lines indicate the eccentric fraction of events identified by N. Gupte et al. (2024; 3 of 57 analyzed events; “Gupte+”) and by I. Romero-Shaw et al. (2022; 4 of 62 analyzed events; “RS+”), respectively.
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Percentiles of the Bayes factor distributions as a function of the eccentric BBH fraction and the measurement uncertainty ﹩{\sigma }_{{\chi }_{{{\rm{eff}}}}}﹩ of χeff. We assume an eccentric BBH fraction of ξecc = 0.05. The vertical yellow dotted line indicates the typical uncertainty obtained in GWTC-3.
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: Joy’s law (latitude variation of the tilt angle) at different stages of BMRs' evolution. (a) At the initial emergence Te. Panels (b)–(e), respectively, represent tilt and Joy’s law fit at approximately 25%, 50%, 75%, and 100% (i.e., at T0) of the backtracked phase. (Hence, panel (c) presents the middle of the backtracking phase.) (f) At the matured phase (Tm). We note that panels (a), (e), and (f) include the whole usable BMRs (1876), while the temporal bins in panels (b), (c), and (d) are chosen in such a way that they accommodate an equal number of BMRs (∼1500). The error bars are computed from the Gaussian fitting of the tilt data in each latitude bin.
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: Distribution of the time intervals Tm − Te for BMRs, where Te is the emergence time identified by backtracking and Tm is the later time when the BMR reaches its maximum flux.
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: (i)–(l) and (m)–(p) The same BMRs that are shown in Figure 2 are now searched in the corresponding (near simultaneous) intensity continua.
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: The distributions of 10,000 of the (a) means and (b) standard deviations of the tilts at Te. Each mean/standard deviation is computed from 100 randomly picked BMRs having matured flux ≥1022 Mx (to be close to the emerging active regions used in H. Schunker et al. 2020).
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: The same as Figure 3(a) but including those additional 307 BMRs for which T0 was the same as Te.
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: Evolution of Joy’s law with the flux emergence during BMRs' early phase. Joy’s law is computed when the BMR flux falls between (a) 0%–5%, (b) 0%–10%, (c) 5%–15%, and (d) 20%–30% of the maximum flux. The number of BMRs belonging to panels (a)–(d) are 436, 729, 809, and 862. It is essential to remember that due to the unequal growth rates of the BMRs, we capture the different phases of BMRs at the fixed flux range.
Paper: Observed Joy’s Law of Bipolar Magnetic Region Tilts at Emergence Supports the Thin Flux Tube Model
Authors: Anu Sreedevi, Bidya Binay Karak, Bibhuti Kumar Jha, Rambahadur Gupta, Dipankar Banerjee
Figure caption: Tilt distribution at different times. Panels (a), (b), and (c), respectively, represent the distributions of the BMR tilt angles at Te, T0, and Tm. The parameters of the Gaussian fit, μ and σ, are printed on each panel.
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Distribution of the maximum difference ﹩{{{\rm{\max }}}}_{t\gt 0}| {\chi }_{{{\rm{eff}}}}(t)-{\chi }_{{{\rm{eff}}}}(0)| ﹩ of χeff during the inspirals of our BBH sample with initially aligned spins and high eccentricity. The inset exemplifies the time evolution of χeff of a typical system.
Paper: Distinguishing the Origin of Eccentric Black Hole Mergers with Gravitational-wave Spin Measurements
Authors: Jakob Stegmann, Davide Gerosa, Isobel Romero-Shaw, Giulia Fumagalli, Hiromichi Tagawa, Lorenz Zwick
Figure caption: Distribution of the cosine of spin tilt angles, ﹩\cos {\theta }_{1}﹩ (left panels) and ﹩\cos {\theta }_{2}﹩ (right panels). We assume spin tilts to be either mutually aligned (maroon) or uncorrelated (teal) at formation. Distributions at detection (fGW = 10 Hz) and BBH formation (fGW = 0.95 Hz) are shown as a filled and dashed histogram, respectively. We assume either maximally spinning BH (top panels) or spin magnitudes extracted from a Beta distribution as in Figure 2 (bottom panels).
Paper: Self-similar Cosmic-Ray Transport in High-resolution Magnetohydrodynamic Turbulence
Authors: Philipp Kempski, Drummond B. Fielding, Eliot Quataert, Robert J. Ewart, Philipp Grete, Matthew W. Kunz, Alexander A. Philippov, James Stone
Figure caption: Diffusion coefficients parallel (blue) and perpendicular (orange) to the background guide field and along the local magnetic field (pink) in our simulations with δBrms/B0 = 2 at different resolutions. κxy is multiplied by a factor of 3 for visualization purposes, and we multiply κ∥ by the effective late-time ballistic velocity of the field lines (see bottom panel of Figure 3 and Equation (1)) to compare with Equation (3), which is the expected relationship for fully magnetized particles diffusing along field lines. Diffusion along z is much more efficient than in the x–y plane, demonstrating that the mean field renders transport extremely anisotropic despite the fact that δBrms/B0 ≈ 2. The horizontal orange lines show the predicted perpendicular diffusion coefficients assuming particles are perfectly tied to field lines, using the late-time κxy of magnetic field lines (bottom panel of Figure 3) and using that particle pitch angles satisfy, on average, 〈∣μ∣〉 = 0.5. At small rL, xy-diffusion thus appears to be well described by transport mediated by the field-line random walk, which turns out to be well converged with resolution. In contrast, κz, which dominates the overall diffusion rate, is not converged with resolution; at the highest resolution, we find an extended range of gyroradii where κz has a weak dependence on particle energy.