adsabs/AstroCLIMB huggingface dataset:
Paper: Homologous Accelerated Electron Beams, a Quasiperiodic Fast-propagating Wave, and a Coronal Mass Ejection Observed in One Fan-spine Jet
Authors: Yadan Duan, Yuandeng Shen, Xinping Zhou, Zehao Tang, Chengrui Zhou, and Song Tan
Figure caption: Panel (a) shows the overview of the source region in which the erupted region of the AIA 131 Å image was overlaid on the extrapolated PFSS field lines. The position of the Earth and STEREO relative to the Sun as shown in the upper left corner; the separation angle between SDO and STEREO-A was about 120 degrees. The red box indicates the field of view (FOV) of the panel (d). Panel (b): the AIA 304 Å running-difference image displays the morphology of the jet, and the blue box represents the FOV of the panel (c). Panel (c): the AIA 304 Å image displays an S-shaped small filament at the base of the jet before it ejects. The black and green contours represent negative and positive magnetic fields of the HMI LOS magnetogram scaled at ±100G, respectively. Panel (d): the reconfigured magnetic configuration of the pseudostreamer from the global PFSS model, which was projected onto AIA 1600 Å image and a smaller-scale fan-spine topology existed at its south edge. The inset image (d1) gives a closer-up 3D view of the fan-spine topology at the south edge of the pseudostreamer, which was reconfigured by another local potential field extrapolation. In panel (d1), the skeleton is outlined by the red curves, and the position of the null point is indicated by a white arrow. In the extrapolation images in panels (a), (d), and (d1), the white and yellow lines, respectively, show the outer (inter) fan structures, while the green ones represent the south part of the pseudostreamer. Note that the green lines in panel (d1) may not be fully open since the local extrapolation is performed with a limited height (∼73 Mm).
Paper: Homologous Accelerated Electron Beams, a Quasiperiodic Fast-propagating Wave, and a Coronal Mass Ejection Observed in One Fan-spine Jet
Authors: Yadan Duan, Yuandeng Shen, Xinping Zhou, Zehao Tang, Chengrui Zhou, and Song Tan
Figure caption: Panels (a1)–(a4): AIA 304 Å sequence images show the eruptive process of the mini-filament.The green arrow points to the filament in panel (a1). Panels (b1)–(b4): time sequence of AIA 1600 Å images demonstrate the flare ribbon variations during the eruptive process. The blue arrows in panel (b2) indicate a semicircular flaring feature. The blue and red contours in panel (b3) are negative and positive magnetic fields of the HMI LOS magnetogram scaled at ±100G, respectively. Panel (c): the time–distance plot along the white arrow in panel (a1). The dark horizontal streak around 10 Mm corresponds to the rising filament body, while bright vertical streaks near 09:08 UT correspond to plasma ejections in the solar jet. These two features are used to roughly derive the projected velocity in the dynamic analysis in Section 2.1.
Paper: Homologous Accelerated Electron Beams, a Quasiperiodic Fast-propagating Wave, and a Coronal Mass Ejection Observed in One Fan-spine Jet
Authors: Yadan Duan, Yuandeng Shen, Xinping Zhou, Zehao Tang, Chengrui Zhou, and Song Tan
Figure caption: Panels (a1)–(a3) are the time sequence of STEREO-A 304 Å running-difference images, and panel (a4) is the STEREO-A 195 Å running-difference image. In panels (a1)–(a4), the black and white arrows mark the traveling ejected material along different magnetic field lines. The green dotted line represents the propagating trajectory of the EUV brightening, with a travel distance of about 816 Mm. Panels (b) and (c): STEREO-A COR1 and LASCO/C2 images show a narrow CME. The blue arrow marks the ejected direction of the jet in panel (b). Panel (d): the extrapolated PFSS field lines overlay in the EUVI 304 Å image, and the white (green) lines represent closed (open) magnetic fields.
Paper: Homologous Accelerated Electron Beams, a Quasiperiodic Fast-propagating Wave, and a Coronal Mass Ejection Observed in One Fan-spine Jet
Authors: Yadan Duan, Yuandeng Shen, Xinping Zhou, Zehao Tang, Chengrui Zhou, and Song Tan
Figure caption: Panel (a1) shows the light curves of GOES 1–8 Å and RHESSI in multiple energy channels from 09:00 UT to 10:00 UT. Panels (a2)–(a3): the radio dynamic spectrum from the Nançay Decametric Array (10–70 MHz) (NDA; Boischot et al. 1980) and RAD1 (RAD2) onboard WIND/WAVES (0.1–10 MHz)(Bougeret et al. 1995) shows the type II radio burst and the type III radio burst. The two asterisks in (a2) mark the frequencies used to calculate the compression ratio. Panels (b1)–(b3) show the time sequence of the Nançay Radioheliograph (NRH; Kerdraon & Delouis 1997) radio source; the green dots represent the eruptive source region.
Paper: Alpha–Proton Differential Flow of the Young Solar Wind: Parker Solar Probe Observations
Authors: P. Mostafavi, R. C. Allen, M. D. McManus, G. C. Ho, N. E. Raouafi, D. E. Larson, J. C. Kasper, and S. D. Bale
Figure caption: Solar wind properties over a 2 hr interval during encounter 5. From top to bottom are the H+ and He++ flux as a function of azimuthal angle (ϕ) in the spacecraft frame, proton and alpha velocities, radial component of the magnetic field, Alfvén speed, and magnitude of differential speed over local Alfvén speed.
Paper: Alpha–Proton Differential Flow of the Young Solar Wind: Parker Solar Probe Observations
Authors: P. Mostafavi, R. C. Allen, M. D. McManus, G. C. Ho, N. E. Raouafi, D. E. Larson, J. C. Kasper, and S. D. Bale
Figure caption: Probability distributions of the alpha–proton differential speed normalized to Alfvén speed for slow to fast solar wind speeds (from left to right). Wind data at 1 au (blue curves) and Helios data between 0.3 and 0.7 au (red curves) are adapted from Ďurovcová et al. (2017) and Marsch et al. (1982), respectively. Green curves are PSP observations close to the Sun at about 0.1 au. Here N is the number of data sets used for each analysis.
Paper: Alpha–Proton Differential Flow of the Young Solar Wind: Parker Solar Probe Observations
Authors: P. Mostafavi, R. C. Allen, M. D. McManus, G. C. Ho, N. E. Raouafi, D. E. Larson, J. C. Kasper, and S. D. Bale
Figure caption: Averages of the alpha–proton differential flow of the Helios and PSP data sets as a function of distance from the Sun for different ranges of solar wind speeds. Helios data are from 0.3 to 1 au. Circles and dashed lines are reproduced from Marsch et al. (1982) and Ďurovcová et al. (2019) fits, respectively. The PSP data are shown with crosses, and the dotted lines connect the different data sets.
Paper: Alpha–Proton Differential Flow of the Young Solar Wind: Parker Solar Probe Observations
Authors: P. Mostafavi, R. C. Allen, M. D. McManus, G. C. Ho, N. E. Raouafi, D. E. Larson, J. C. Kasper, and S. D. Bale
Figure caption: The 6 hr averages of the alpha–proton differential velocity are shown as a function of time of arrival to the spacecraft in a log–log scale. Helios and Ulysses data are adapted from Marsch et al. (1982) and Neugebauer et al. (1996), respectively.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Orbital evolution pathways used in our model. Solid and dashed lines show the evolution pathways in Case 1 and Case 2, respectively. The square and circle are the core formation locations for Case 1 and Case 2, respectively. The cross corresponds to Jupiter. The red and blue areas show the sweet spot for planetesimal accretion (SSP) (Shibata et al. 2021) with Rpl = 107.0 cm and Rpl = 106.0 cm, respectively.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Upper panels: the cumulative captured mass of planetesimals as a function of calculation time t − t0 in Case 1 (left) and in Case 2 (right). The different colors correspond to the different sizes of planetesimals. The planetesimal accretion rate decreases with time in Case 1; however, a second rapid planetesimal accretion occurs before the end of its formation in Case 2. Lower panels: the heavy-element mass fraction Zp that formed in Jupiter’s envelope as a function of the normalized mass m/Mp. The bin’s width is set to be 0.05 m/MJ. Planetesimals accreted during the second accretion phase are deposited into the outer envelope.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Metallicity of the uppermost layer Ztop as a function of the mass of the uppermost layer Mconv,top. The metallicity is normalized by the protosolar metallicity Zprotosolar. We adopt 0.0142, obtained in Asplund et al. (2009), to be consistent with our disk model. The blue and red areas show the oxygen abundance retrieved by Juno (﹩{2.7}_{-1.7}^{+2.4}﹩; Li et al. 2020) and the atmospheric composition suggested by Galileo (2–4; Atreya et al. 2020). Solid and dashed lines show the results in Case 1 and Case 2, respectively. Here, we show the cases of Rpl = 106.5 cm. We also plot the cases where the planetesimal disk is twice heavier than the disk in our model with thin lines.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Mass of captured planetesimals as a function of the initial semimajor axis of planetesimals. Red and blue correspond to Case 1 and Case 2, respectively. The meshed textures show the mass of the captured planetesimals when Mp > 0.8MJ. Here we show the cases of Rpl = 106.5 cm. Bin width is set to 0.5 au. The gray filled areas show the initial feeding zones of proto-Jupiter.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Sketch for planetesimal accretion and the forming composition gradient in Jupiter envelope. The above panel shows the case when proto-Jupiter migrates from 7 to 5 au. Infalling gas covers the envelope enriched via planetesimal accretion and only the inner region of the Jupiter envelope is enriched with heavy elements. The bottom panel shows the case when proto-Jupiter migrates from 20 to 5 au. If the protoplanet reaches the sweet spot for accretion just before the end of gas accretion, planetesimals are deposited into the outer envelope. A several-times-enriched Jupiter atmosphere can be formed if the size of the outermost convective layer is as small as ≲0.2MJ.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Disk profile used in our model. The solid line shows the planetesimal surface density profile. We adopt the solid-to-gas ratio used in Turrini et al. (2021). The dashed lines show the gas surface density profile when Mp = 0.4MJ (red line) and Mp = 1.0MJ (blue line) in Case 2.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Evolution of timescales used in our model. The red and blue lines are the gas accretion timescale τacc and planetary migration timescale τtide, respectively. The solid and dashed lines are cases of Mth = 10−2 and 10−3, respectively. The dotted black line shows the depletion timescale τdep = 1 × 106 yr.
Paper: Enrichment of Jupiter’s Atmosphere by Late Planetesimal Bombardment
Authors: Sho Shibata, and Ravit Helled
Figure caption: Same as Figure 2 but using a small-disk model (left), steep-disk model (middle), and flat-disk model (right). In the upper panels, we normalize the cumulative captured mass using the total solid mass used in each simulation. We adapt the evolution pathways of Case 2.
Paper: Evidence from Disrupted Halo Dwarfs that r-process Enrichment via Neutron Star Mergers is Delayed by ≳500 Myr
Authors: Rohan P. Naidu, Alexander P. Ji, Charlie Conroy, Ana Bonaca, Yuan-Sen Ting, Dennis Zaritsky, Lieke A. C. van Son, Floor S. Broekgaarden, Sandro Tacchella, Vedant Chandra, Nelson Caldwell, Phillip Cargile, and Joshua S. Speagle
Figure caption: Kraken in the APOGEE data set. [Mg/Fe] vs. [Fe/H] for APOGEE stars in the inner 5 kpc of the galaxy selected to have low energy (energy cut from Figure 2). The eccentric stars (right panel) show a metal-poor, Mg-enhanced population that is absent at lower eccentricities (left panel). This preferential concentration at e > 0.5 tracks the Kraken GCs and is expected from dynamical friction considerations for a high-mass-ratio merger (e.g., Naidu et al. 2021).
Paper: Evidence from Disrupted Halo Dwarfs that r-process Enrichment via Neutron Star Mergers is Delayed by ≳500 Myr
Authors: Rohan P. Naidu, Alexander P. Ji, Charlie Conroy, Ana Bonaca, Yuan-Sen Ting, Dennis Zaritsky, Lieke A. C. van Son, Floor S. Broekgaarden, Sandro Tacchella, Vedant Chandra, Nelson Caldwell, Phillip Cargile, and Joshua S. Speagle
Figure caption: Selecting Kraken and GSE samples. Panel (a): All APOGEE stars that satisfy our quality cuts are shown in the [Mg/Mn] vs. [Al/Fe] chemical plane that has been used to separate accreted stars from in situ stars (e.g., Das et al. 2020). We use the brown dashed line to demarcate the two visibly distinct populations. Panel (b): Total orbital energy vs. the z-component of angular momentum for accreted stars identified via panel (a). We select GSE as a high-energy population and Kraken as the low-energy population motivated by the location of their associated GCs in this plane. Panel (c): The final selected Kraken (purple) and GSE (golden) samples (see Equations (1) and (2)) show tight, coherent [Mg/Fe] vs. [Fe/H] sequences characteristic of distinct dwarfs. The Kraken sequence is α-enhanced with no visible “knee,” which is expected for a galaxy disrupted earlier, and forming stars more efficiently than GSE.
Paper: Evidence from Disrupted Halo Dwarfs that r-process Enrichment via Neutron Star Mergers is Delayed by ≳500 Myr
Authors: Rohan P. Naidu, Alexander P. Ji, Charlie Conroy, Ana Bonaca, Yuan-Sen Ting, Dennis Zaritsky, Lieke A. C. van Son, Floor S. Broekgaarden, Sandro Tacchella, Vedant Chandra, Nelson Caldwell, Phillip Cargile, and Joshua S. Speagle
Figure caption: Magellan/MIKE abundances for GSE (golden squares) and Kraken (purple circles). Each panel shows the median abundances as dashed lines. Typical errors are indicated in the top-left diagram corner. Notice that Kraken has a relative dearth of elements that are associated with “delayed” sources (e.g., Eu: NSMs, Fe: Type Ia SNe, Ba: NSMs+AGBs) across all panels, supporting the case for a more efficient, shorter star formation history compared to GSE.
Paper: Evidence from Disrupted Halo Dwarfs that r-process Enrichment via Neutron Star Mergers is Delayed by ≳500 Myr
Authors: Rohan P. Naidu, Alexander P. Ji, Charlie Conroy, Ana Bonaca, Yuan-Sen Ting, Dennis Zaritsky, Lieke A. C. van Son, Floor S. Broekgaarden, Sandro Tacchella, Vedant Chandra, Nelson Caldwell, Phillip Cargile, and Joshua S. Speagle
Figure caption: Simple models for the evolution of [Eu/Mg]. Each track shown in blue is constrained to pass through the Kraken point (purple star) by adjusting RCCSNe/RNSMs and the [Eu/Mg]CCSNe. On these tracks every point corresponds to an M⋆ = 5 × 108M⊙ galaxy. The predicted [Eu/Mg] distributions shown on the right include a 0.1 dex uncertainty for comparison with observations. The median [Eu/Mg] we measure is shown as shaded regions, and all Eu-free stars are set to [Eu/Mg] = −1. Statistical errors on the median [Eu/Mg] for all galaxies shown in the left panels are smaller than the star-shaped markers used to represent them. Top: models where Eu arises purely from NSMs require minimum delay times ≈500–1000 Myr to match the rapid evolution across Kraken and GSE (top left). Such delay times imply the existence of substantial fractions of Eu-free stars inconsistent with observations (top right). Bottom: when contributions from both CCSNe and NSMs are allowed, there is a “floor” for [Eu/Mg] at early times due to CCSNe followed by a rapid rise from delayed NSMs. Models with ﹩{t}_{\min }\approx 500\mbox{--}1000﹩ Myr reproduce the abundances in Kraken and GSE as well as in dwarfs with extended SFHs (Sgr, LMC, and Fornax). The predicted [Eu/Mg] distribution (right panel) is bimodal, with each mode corresponding to the CCSNe-dominated phase and NSM-dominated phase of the tracks.
Paper: Evidence from Disrupted Halo Dwarfs that r-process Enrichment via Neutron Star Mergers is Delayed by ≳500 Myr
Authors: Rohan P. Naidu, Alexander P. Ji, Charlie Conroy, Ana Bonaca, Yuan-Sen Ting, Dennis Zaritsky, Lieke A. C. van Son, Floor S. Broekgaarden, Sandro Tacchella, Vedant Chandra, Nelson Caldwell, Phillip Cargile, and Joshua S. Speagle
Figure caption: Left: schematic of our preferred scenario featuring both rare CCSNe and NSMs with a ﹩{t}_{\min }=750\,\mathrm{Myr}﹩. Only systems with stellar masses comparable to Kraken and GSE are shown for a fair comparison. Right: the relative contribution of rCCSNE and NSMs to the total Eu produced as a function of total star formation duration under the assumption of a top-hat SFH. rCCSNe contribute significantly at early times in galaxies like Kraken (≈50% of Eu), whereas in galaxies like Sgr and Fornax ≈85% of Eu arises from NSMs.
Paper: The Unanticipated Phenomenology of the Blazar PKS 2131–021: A Unique Supermassive Black Hole Binary Candidate
Authors: S. O'Neill, S. Kiehlmann, A. C. S. Readhead, M. F. Aller, R. D. Blandford, I. Liodakis, M. L. Lister, P. Mróz, C. P. O'Dea, T. J. Pearson, V. Ravi, M. Vallisneri, K. A. Cleary, M. J. Graham, K. J. B. Grainge, M. W. Hodges, T. Hovatta, A. Lähteenmäki, J. W. Lamb, T. J. W. Lazio, W. Max-Moerbeck, V. Pavlidou, T. A. Prince, R. A. Reeves, M. Tornikoski, P. Vergara de la Parra, and J. A. Zensus
Figure caption: The 14.5–15.5 GHz light curve of PKS 2131−021. The Haystack data are shown by the green squares, the UMRAO data by the brown triangles, and the OVRO data by the blue circles. Note the excellent agreement between Haystack and UMRAO and between UMRAO and OVRO in the regions of overlap. The light curve shows three distinct epochs of activity: In epoch 1 (MJD < 45,500) there is a strong periodic signal, P1 = 1729.1 ± 32.4 days; in epoch 2 (45,500 < MJD < 52,850) this periodic signal is absent; in epoch 3 (MJD > 52,850) the periodic signal of epoch 1 returns, with P3 = 1760.4 ± 5.3 days, in phase but with lower amplitude than that of epoch 1. The solid green line shows the least-squares sine-wave fit to the Haystack data, and the dotted blue line shows the least-squares sine-wave fit to the OVRO data extrapolated backward to provide a comparison with the Haystack data. The periods of the Haystack and OVRO sine-wave fits match to ≲2%. The phase of the OVRO periodic signal extrapolated back to epoch 1 matches to ∼10% of the period.
Paper: The Unanticipated Phenomenology of the Blazar PKS 2131–021: A Unique Supermassive Black Hole Binary Candidate
Authors: S. O'Neill, S. Kiehlmann, A. C. S. Readhead, M. F. Aller, R. D. Blandford, I. Liodakis, M. L. Lister, P. Mróz, C. P. O'Dea, T. J. Pearson, V. Ravi, M. Vallisneri, K. A. Cleary, M. J. Graham, K. J. B. Grainge, M. W. Hodges, T. Hovatta, A. Lähteenmäki, J. W. Lamb, T. J. W. Lazio, W. Max-Moerbeck, V. Pavlidou, T. A. Prince, R. A. Reeves, M. Tornikoski, P. Vergara de la Parra, and J. A. Zensus
Figure caption: MOJAVE 15 GHz VLBI maps (Lister et al. 2018) matched to the OVRO 15 GHz light curve (blue circles) and least-squares sine-wave fit to the OVRO data (blue line). The total flux densities measured by MOJAVE are shown by the red asterisks. The maps show the basic core−jet structure of PKS 2131−021 on parsec scales. The bar at the lower left indicates the scale of 5 mas (∼42 pc) of all the maps, and the small cross indicates the typical FWHM beam size and orientation. Detailed comparison of the maps, models, and light curve shows that it is the core (primarily) and innermost component (partly), at ∼0.3 mas from the core, that are responsible for the periodic flux density variations.
Paper: The Unanticipated Phenomenology of the Blazar PKS 2131–021: A Unique Supermassive Black Hole Binary Candidate
Authors: S. O'Neill, S. Kiehlmann, A. C. S. Readhead, M. F. Aller, R. D. Blandford, I. Liodakis, M. L. Lister, P. Mróz, C. P. O'Dea, T. J. Pearson, V. Ravi, M. Vallisneri, K. A. Cleary, M. J. Graham, K. J. B. Grainge, M. W. Hodges, T. Hovatta, A. Lähteenmäki, J. W. Lamb, T. J. W. Lazio, W. Max-Moerbeck, V. Pavlidou, T. A. Prince, R. A. Reeves, M. Tornikoski, P. Vergara de la Parra, and J. A. Zensus
Figure caption: Radio light curves of the entire source from UMRAO at 14.5 GHz (brown triangles), OVRO at 15.0 GHz (filled blue circles), and MOJAVE at 15.0 GHz (red asterisks), as well as individual parsec-scale jet features as measured by the MOJAVE program.
Paper: The Unanticipated Phenomenology of the Blazar PKS 2131–021: A Unique Supermassive Black Hole Binary Candidate
Authors: S. O'Neill, S. Kiehlmann, A. C. S. Readhead, M. F. Aller, R. D. Blandford, I. Liodakis, M. L. Lister, P. Mróz, C. P. O'Dea, T. J. Pearson, V. Ravi, M. Vallisneri, K. A. Cleary, M. J. Graham, K. J. B. Grainge, M. W. Hodges, T. Hovatta, A. Lähteenmäki, J. W. Lamb, T. J. W. Lazio, W. Max-Moerbeck, V. Pavlidou, T. A. Prince, R. A. Reeves, M. Tornikoski, P. Vergara de la Parra, and J. A. Zensus
Figure caption: The angular separation of jet components from the core vs. time for individual Gaussian model fitted features in PKS 2131−021 on the MOJAVE program. Colored symbols indicate robust features for which kinematic fits were obtained. The identification number is overlined if an acceleration model was fitted and indicated a ≥3σ acceleration. An underlined identification number indicates a feature with nonradial motion. The black circles represent Gaussian components fitted to the jet emission that could not be clearly cross-identified over a minimum of five epochs.
Paper: The Unanticipated Phenomenology of the Blazar PKS 2131–021: A Unique Supermassive Black Hole Binary Candidate
Authors: S. O'Neill, S. Kiehlmann, A. C. S. Readhead, M. F. Aller, R. D. Blandford, I. Liodakis, M. L. Lister, P. Mróz, C. P. O'Dea, T. J. Pearson, V. Ravi, M. Vallisneri, K. A. Cleary, M. J. Graham, K. J. B. Grainge, M. W. Hodges, T. Hovatta, A. Lähteenmäki, J. W. Lamb, T. J. W. Lazio, W. Max-Moerbeck, V. Pavlidou, T. A. Prince, R. A. Reeves, M. Tornikoski, P. Vergara de la Parra, and J. A. Zensus
Figure caption: Maps of PKS 2131−021 on different angular scales. (a) VLA 1.4 GHz map from Rector & Stocke (2001). (b) VLA 4.86 GHz map from Rector & Stocke (2003); the gray scale shows the 4.86–8.46 GHz spectral index, which shows that the core has a flat spectrum and the jet has a steep spectrum. (c) EVN+MERLIN 4.99 GHz map from Cassaro et al. (2002). The rms noise level is 0.2 mJy beam−1, and the peak flux density is 1349 mJy beam−1. (d) Stack of 24 MOJAVE images (Lister et al. 2019) from 1995 July 28 to 2012 May 24. FWHM beamwidth: 1.04 × 0.45 mas in position angle −3°. Contours: ﹩\sqrt{2}\times 1.714﹩ mJy beam−1.