adsabs/AstroCLIMB huggingface dataset:
Paper: Impulsively Accelerated Ions as the Source of Ion Acoustic Waves in Solar Wind
Authors: R. E. Ergun, L. G. Strus, D. M. Malaspina, I. H. Cairns, C. A. Cattell
Figure caption: (a) Examples of impulsively accelerated ion distributions that are used in the linear wave analysis. Each of the distributions has ﹩\delta {f}_{i}/{f}_{i}=1.25﹩ and δ v = 5 km s−1 centered at v ps. (b) The growth rate (color) vs. ω and k for 25 ion distributions with v ps ranging from 30 to 150 km s−1 in increments of 5 km s−1. The gray lines represent ω = kv ps for each of the 25 ion distributions. The black line marks ω and k at maximum growth rate. The highest growth rate is when ω/k ∼ v  ia , near 60 km s−1. (c) A cartoon of the relative motion of PSP with respect to impulsively accelerated ions. The accelerated ions are away from the Sun and carried anti-sunward in the solar wind at a speed of 167 km s−1 along  B . (d) A comparison of the predicted frequencies as a function of time with measured frequencies. The predicted frequencies, measured frequencies, and how they evolve in time are consistent. By choosing the location of PSP to be 35 km from the impulsive event (see cartoon), the predicted duration of the event is made to match that of the measured event.
Paper: Impulsively Accelerated Ions as the Source of Ion Acoustic Waves in Solar Wind
Authors: R. E. Ergun, L. G. Strus, D. M. Malaspina, I. H. Cairns, C. A. Cattell
Figure caption: One-dimensional test-particle simulations of impulsive acceleration. (a) Ion phase-space density as a function of velocity and distance. The image is a snapshot 300 ms after a 15 V impulsive acceleration that endures for 100 ms. The electric field is overplotted in red. (b) Ion distributions (f  i  vs. v) at various distances from the impulse (marked on plot) 300 ms after the impulse. The distributions are offset for better viewing. (c) A series of ion distributions (f  i  vs. v) at set times after the impulse. All of the ion distributions are measured 40 km from the acceleration source. (d)–(f) Ion distributions that result from impulsive acceleration that imparts identical velocities into each ion. The plots have an identical format to those in (a)–(c).
Paper: Impulsively Accelerated Ions as the Source of Ion Acoustic Waves in Solar Wind
Authors: R. E. Ergun, L. G. Strus, D. M. Malaspina, I. H. Cairns, C. A. Cattell
Figure caption: A frequency–time spectrogram of a short burst of ion acoustic-like wave emissions. The vertical axis is frequency, the horizontal axis is time, and the color represents the energy density of the electric field. The magenta line is the ion plasma frequency. The overplotted symbols show the center frequency of each spectra and an estimate of the uncertainty.
Paper: Impulsively Accelerated Ions as the Source of Ion Acoustic Waves in Solar Wind
Authors: R. E. Ergun, L. G. Strus, D. M. Malaspina, I. H. Cairns, C. A. Cattell
Figure caption: A reevaluation of the predicted frequency vs. time behavior of driven ion acoustic waves under (a)–(c) equal-energy impulsive acceleration and (d)–(f) equal-velocity impulsive acceleration. The format of figures is identical to that in Figure (4).
Paper: Impulsively Accelerated Ions as the Source of Ion Acoustic Waves in Solar Wind
Authors: R. E. Ergun, L. G. Strus, D. M. Malaspina, I. H. Cairns, C. A. Cattell
Figure caption: The predicted frequency as a function of time displaying a falling tone. In this example, the ion acceleration is in the direction opposite to that shown in Figure 4(c). PSP is 20 km from the location of the impulsive ion acceleration event at t = 0. The Mach ∼3 solar wind sweeps the accelerated ions past PSP, which sees the lower-velocity part of the impulsively accelerated ions first then the higher-velocity ions, resulting in the apparent falling tone.
Paper: A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Katie Chamberlain, Ekta Patel, Gurtina Besla, Paul Torrey, Vicente Rodriguez-Gomez
Figure caption: The median merger timescale as a function of redshift for low-mass (green) and high-mass (pink) pairs in our merger sample. Shaded regions represent the first and third quartile spread on the median. The thick dotted black line at low redshifts shows the time to z = 0 (the lookback time) as a function of redshift, which sets the upper bound for the merger timescale that a merging pair can have. The thin black line shows the Hubble time as a function of redshift multiplied by a constant β = 0.35, which approximates the median time until merger from z = 6 to z ∼ 1. The median time until merger is similar for low-mass and high-mass pairs, and rises from z = 6 to a peak at z ∼ 0.75, then decreases to z = 0.
Paper: A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Katie Chamberlain, Ekta Patel, Gurtina Besla, Paul Torrey, Vicente Rodriguez-Gomez
Figure caption: The distribution of merger timescales for low-mass (top) and high-mass (bottom) pairs as a function of physical separation at z = 0.5, 1, 1.5, 2, 3, 4, 5, and 6. The color bars show the percentage of the total number of pairs at each redshift (given in the bottom right corner of each panel) that are in a given separation bin. In each of the first panels, the gray horizontal dashed line shows the time remaining in the simulation, above which there are no mergers. The thin black line is a linear fit to each set of data with slopes from Table 1 and described in more detail in the text. We find (i) a positive correlation between separation and the time until merger at each selected redshift—the lowest separation pairs tend to have the shortest merger timescales; (ii) given a redshift and separation, the low-mass merger timescale is longer than the high-mass merger timescale, i.e., low-mass pairs at z = 1 with separations r sep < 100 kpc merge within 6 Gyr, while high-mass pairs in the same separation range merge within 3 Gyr; (iii) merger timescales are longer for lower redshift pairs; and (iv) the spread of merger timescales and separations increase with decreasing redshift.
Paper: A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Katie Chamberlain, Ekta Patel, Gurtina Besla, Paul Torrey, Vicente Rodriguez-Gomez
Figure caption: Selection of example orbits of low-mass major pairs that pass the pair selection criteria at z = 1.5, showing the separation between the primary and secondary as a function of lookback time. (Top) Orbits of pairs that merge before z = 0. (Middle) Orbits of pairs that do not merge before z = 0 (nonmergers), but are likely to merge if the simulation continued. (Bottom) Orbits of pairs that do not merge before z = 0 (nonmergers) and are unlikely to do so in the future ∼2 Gyr (past the end of the simulation). Solid lines represent the postinfall orbits, i.e., after the pair share a common FoF group. Dashed lines show the preinfall portion of the orbit. Triangle points in the first panel show the first redshift after merger where the orbit has a separation of 0 kpc. The vertical gray line marks z = 1.5 at a lookback time of 9.5 Gyr.
Paper: A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Katie Chamberlain, Ekta Patel, Gurtina Besla, Paul Torrey, Vicente Rodriguez-Gomez
Figure caption: (Top) The median merger timescale as a function of redshift for low-mass (green) and high-mass (pink) pairs with 3D physical separations greater than 10 kpc and less than 50, 70, 100, 150, 200, and 300 kpc from left to right. (Bottom) The median time until merger as a function of redshift for pairs with physical separations greater than 10 kpc and less than 0.25, 0.5, 1, 1.5, 2, and 2.5 R vir from left to right. The thin black line is the same as shown in Figure 5, and goes as the Hubble time 1/H(z) multiplied by 0.35 (see Section 4.2 for additional details). The time until merger increases from z = 4 to z ∼ 0.5–0.75, at which point the time until merger decreases to zero since all low redshift mergers must have short merger timescales to merge before the end of the simulation at z = 0.
Paper: A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Katie Chamberlain, Ekta Patel, Gurtina Besla, Paul Torrey, Vicente Rodriguez-Gomez
Figure caption: The number of unique low-mass (green) and high-mass (pink) pairs in our orbit catalog as a function of redshift. Orbits are only defined between first infall and the merger redshift (for merging pairs) or z = 0 (for nonmerging pairs). The solid lines show the total number of pairs at a given redshift (including nonmergers and mergers), while dashed lines show the number of pairs at a given redshift that will merge before z = 0. The decrease in the number of unique low-mass pairs from z = 2 to z = 0 is due to pairs being removed from the sample via mergers.
Paper: A Physically Motivated Framework to Compare the Merger Timescales of Isolated Low- and High-mass Galaxy Pairs Across Cosmic Time
Authors: Katie Chamberlain, Ekta Patel, Gurtina Besla, Paul Torrey, Vicente Rodriguez-Gomez
Figure caption: The fraction of low-mass (green) and high-mass (pink) orbits that merge before z = 0 shown as a function of redshift. The horizontal line shows a merger fraction of 0.9, or 90%. High-mass pairs have merger fractions greater than 0.9 for z > 1.1, and low-mass pairs for z > 1.6. The sharp decline of the merger fraction to zero at low redshift is a nonphysical feature of the simulation ending at z = 0. Only orbits with sufficiently short merger timescales will merge at redshifts z ≃ 1.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: An echelle diagram for TIC 435850195, showing the tidally tilted δ Sct pulsations. The abscissa is labeled by the echelle phase, which is the pulsation frequency ν modulo the orbital period, divided by the orbital period. The sizes of the points are scaled linearly according to their amplitudes in the periodogram of the light curve. From our analysis, we were able to extract 16 multiplets of tidally tilted pulsations. The doublet dipoles have been circled based on their pulsation axes. The numbered dipole doublets are shown in Figures 8 and 9; the triplets A and B are further discussed in Section 4.2.2.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: The amplitude (left) and phase (right) variations of the six strongest Y 10x  modes in TIC 435850195, as a function of orbital phase. These modes exhibit amplitude maxima at the primary eclipse (phases 0, 1, and 2) and amplitude minima at the maxima of the ELVs (phases 0.25, 0.75, 1.25, and 1.75). These modes also undergo a π phase shift at minimum amplitude. The abrupt 2π jumps in phase are an artifact of the cyclic nature of the phases and are not physically meaningful.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: The best-fit SED. The yellow and green lines are the best-fit model atmospheres from F. Castelli & R. L. Kurucz (2003) for the primary and secondary, respectively, while the thicker purple line is the sum of the two models. At nearly all wavelengths, the primary star’s emission dominates the secondary’s by at least 2 orders of magnitude. We have added a horizontal error bar to show the width of the GALEX far- and near-ultraviolet bandpasses, and an upper limit for the measurement in the W4 band. The uncertainties of ∼10% on each flux point are too small to be seen at this scale.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: Posterior distributions for stellar parameters from the joint MCMC fit to the light curve and the SED. The top panels show the mass, radius, and temperature of the primary (in gray), as well as the inclination (in tan); the bottom panels show the mass, radius, and temperature of the secondary (in magenta), and the age of the star (in turquoise). The median value is denoted by the solid vertical black lines, while the 1σ confidence intervals are denoted by the dotted black lines. Note that even though we fit for the age indirectly in terms of the “equivalent evolutionary phase” (EEP), we show the posterior for the age in Gyr. Prior to the histogram calculation, the ages were normalized by the density of EEP samples in that particular age range.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: Our best-fit model to the binned, folded, Fourier-reconstructed light curve of TIC 435850195, along with the residuals. The residual structure around the times of eclipse could be partially explained by our use of fixed limb darkening coefficients, rather than letting them be free parameters.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: The DFT (D. W. Kurtz 1985) of TIC 435850195, with sequential subtractions of the EB signal in the raw light curve (visible in the top panel) and the δ Sct pulsations (visible in the middle panel). Each set of periodic signals was fit for using least squares and then subtracted from the light curve; the bottom panel shows the DFT of the residual light curve, after both the EB signal and pulsations were fitted and removed. Note the differing scales between the top panel and the lower two.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: A ∼3.5 day portion of the TESS light curve of TIC 435850195 from the QLP (C. X. Huang et al. 2020a, 2020b), sampled at 200 s cadence. The amplitudes and phases of most of the pulsation modes are seen to vary systematically with the orbital phase. There are also prominent ellipsoidal light variations (discussed further in Section 3.1.2) and prominent primary eclipses.
Paper: TIC 435850195: The Second Triaxial Tidally Tilted Pulsator
Authors: Rahul Jayaraman, Saul A. Rappaport, Brian Powell, Gerald Handler, Mark Omohundro, Robert Gagliano, Veselin Kostov, Jim Fuller, Donald W. Kurtz, Valencia Zhang, George Ricker
Figure caption: Hertzsprung–Russell diagram showing evolutionary tracks for stars with masses between 0.7 and 1.9 M ⊙ from the MIST tracks (J. Choi et al. 2016; A. Dotter 2016). This diagram also shows the locations of the primary and secondary components, as stars and squares, respectively, for both the TIC 184743498 (Z24) and TIC 435850195 systems.
Paper: Stellar Models are Reliable at Low Metallicity: An Asteroseismic Age for the Ancient Very Metal-poor Star KIC 8144907
Authors: Daniel Huber, Ditte Slumstrup, Marc Hon, Yaguang Li, Victor Aguirre Børsen-Koch, Timothy R. Bedding, Meridith Joyce, J. M. Joel Ong, Aldo Serenelli, Dennis Stello, Travis Berger, Samuel K. Grunblatt, Michael Greklek-McKeon, Teruyuki Hirano, Evan N. Kirby, Marc H. Pinsonneault, Arthur Alencastro Puls, Joel Zinn
Figure caption: Left: iron abundance vs. age for stars with ages from detailed asteroseismic modeling (orange circles) and subgiants with ages from isochrone fitting by M. Xiang & H.-W. Rix (2022, gray logarithmic heat map) with kinematics consistent with an “in situ” population (e < 0.8, Lz > 0 kpc km s−1). Literature asteroseismic ages are taken from T. L. Campante et al. (2015), V. Silva Aguirre et al. (2015, 2017), W. J. Chaplin et al. (2020), and T. Li et al. (2020). Right: same as left panel but for stars with kinematics consistent with an accreted population (e > 0.8, Lz < −500 kpc km s−1). The abundances and kinematics of KIC 8144907 are consistent with either population.
Paper: Stellar Models are Reliable at Low Metallicity: An Asteroseismic Age for the Ancient Very Metal-poor Star KIC 8144907
Authors: Daniel Huber, Ditte Slumstrup, Marc Hon, Yaguang Li, Victor Aguirre Børsen-Koch, Timothy R. Bedding, Meridith Joyce, J. M. Joel Ong, Aldo Serenelli, Dennis Stello, Travis Berger, Samuel K. Grunblatt, Michael Greklek-McKeon, Teruyuki Hirano, Evan N. Kirby, Marc H. Pinsonneault, Arthur Alencastro Puls, Joel Zinn
Figure caption: Left: power spectrum of the 4 yr Kepler timeseries of KIC 8144907 centered on the oscillations. Middle: échelle diagram (grayscale) and extracted frequencies for radial (circles), dipole (squares), and quadrupole (diamonds) modes. Right: échelle diagram showing frequencies from the best-fitting model from BeSPP (Section 3.3.1) before (faint open symbols) and after (open symbols) applying a surface correction. Gray symbols show the observed frequencies.
Paper: Stellar Models are Reliable at Low Metallicity: An Asteroseismic Age for the Ancient Very Metal-poor Star KIC 8144907
Authors: Daniel Huber, Ditte Slumstrup, Marc Hon, Yaguang Li, Victor Aguirre Børsen-Koch, Timothy R. Bedding, Meridith Joyce, J. M. Joel Ong, Aldo Serenelli, Dennis Stello, Travis Berger, Samuel K. Grunblatt, Michael Greklek-McKeon, Teruyuki Hirano, Evan N. Kirby, Marc H. Pinsonneault, Arthur Alencastro Puls, Joel Zinn
Figure caption: Left: iron abundance vs. frequency of maximum power for stars with asteroseismic detections. Literature values (black points) are from M. H. Pinsonneault et al. (2014), A. Serenelli et al. (2017), T. Matsuno et al. (2021b), and J. Schonhut-Stasik et al. (2024). Individual literature values are from W. J. Chaplin et al. (2020, ν Indi), M. Valentini et al. (2019, EPIC 206443679), and S. Deheuvels et al. (2014, KIC 7341231). New data from this study are shown as red symbols. The shaded area marks stars generally not amenable to frequency modeling (﹩{\nu }_{\max }\lt 100﹩                      μHz). Right: same as the left panel but showing α abundance vs. metallicity.
Paper: Stellar Models are Reliable at Low Metallicity: An Asteroseismic Age for the Ancient Very Metal-poor Star KIC 8144907
Authors: Daniel Huber, Ditte Slumstrup, Marc Hon, Yaguang Li, Victor Aguirre Børsen-Koch, Timothy R. Bedding, Meridith Joyce, J. M. Joel Ong, Aldo Serenelli, Dennis Stello, Travis Berger, Samuel K. Grunblatt, Michael Greklek-McKeon, Teruyuki Hirano, Evan N. Kirby, Marc H. Pinsonneault, Arthur Alencastro Puls, Joel Zinn
Figure caption: Subaru/HDS spectrum of KIC 8144907 near the Mg triplet. The red line shows a Keck/HIRES spectrum of the solar-metallicity star KIC 10006158 for comparison.
Paper: The Interplay between the Disk and Corona of the Changing-look Active Galactic Nucleus 1ES 1927+654
Authors: Ruancun Li, Claudio Ricci, Luis C. Ho, Benny Trakhtenbrot, Erin Kara, Megan Masterson, Iair Arcavi
Figure caption: Light curves of the disk (red-filled circles), blackbody (blue-filled squares), and corona (green-filled diamonds) components. The x-axis shows days since the optical outburst on 2017 December 23. The bolometric light curve and its 1σ  uncertainty are plotted as the black curve and the gray shaded region, respectively. The stars at t = 0 and the horizontal dashed lines mark the luminosity of individual subcomponents before the optical outburst (No. 0). The vertical dashed lines separate the four evolution epochs discussed in Section 4.1. The luminosity is in erg s−1 (left y-axis) and in Eddington units (right y-axis; for M BH = 1.36 ×  106 M ⊙; R. Li et al. 2022).
Paper: The Interplay between the Disk and Corona of the Changing-look Active Galactic Nucleus 1ES 1927+654
Authors: Ruancun Li, Claudio Ricci, Luis C. Ho, Benny Trakhtenbrot, Erin Kara, Megan Masterson, Iair Arcavi
Figure caption: Example of our broadband SED modeling for the 2018 December 12 observation. In the left panel (a), the gray points show the original broadband data, where all X-ray spectra were visually rebinned to have an S/N = 10. To better illustrate the intrinsic SED, we show the data corrected for dust reddening and interstellar medium absorption based on our best-fit result. The data include the 250 Å binned LCO spectrum (red), the photometric points from Swift UVOT images (green), the 0.3–3 keV soft X-ray spectrum from the XMM-Newton EPIC PN camera (blue), and the 3–10 keV hard X-ray spectrum from merging the NuSTAR FPMA and FPMB cameras (purple). The black curve shows our best-fit final model (see Section 3.2.4), which consists of four components: a geometrically thin accretion disk (red), a blackbody that peaks in the soft X-ray band (blue), a thermally Comptonized continuum (green), and a broad Gaussian feature at ∼1 keV (cyan). The right panel shows the data/model ratio for the four different models outlined in Section 3.2 (from top to bottom): (b) a phenomenological model consisting of a single-temperature blackbody and a power law (zbbody+zpower law); (c) a phenomenological model consisting of an accretion disk and a power law (zashift ×  diskbb+zpower law); (d) a physical model consisting of a thermalized disk, a warm Comptonized corona, and a hot Comptonized corona (agnslim) (A. Kubota & C. Done 2019); (e) a physical model consisting of an accretion disk, a blackbody describing the inner hot accretion flow, and a thermally Comptonized continuum (zashift × diskbb+zbbody+nthComp). The reduced χ 2 obtained by applying these models is listed in the four subpanels.
Paper: The Interplay between the Disk and Corona of the Changing-look Active Galactic Nucleus 1ES 1927+654
Authors: Ruancun Li, Claudio Ricci, Luis C. Ho, Benny Trakhtenbrot, Erin Kara, Megan Masterson, Iair Arcavi
Figure caption: Intrinsic SED models for the four evolution epochs discussed in Section 4.1. In each panel, the dashed–dotted curve and black error bars show the best-fit intrinsic SED model and the broadband data used, at roughly the beginning of the epoch. The solid curve shows the best-fit intrinsic SED models at the end of each epoch: 2018 May 17 (I; dark green, upper left), 2018 October 3 (II; lime, upper right), 2019 May 7 (III; orange, lower right), and 2021 January 12 (IV; red, lower left). The dashed curves show the four subcomponents: thin disk (red), blackbody (blue), corona (green), and broad Gaussian profile (cyan). Arrows mark the evolution tracks for the different subcomponents, with red for thin disk, blue for blackbody, and green for corona. In panel I, the black circles with error bars show the host galaxy subtracted, pre-outburst UV flux from GALEX.