bluuebunny/crossref_metadata_2025_split huggingface dataset:
Korg: Fitting, Model Atmosphere Interpolation, and Brackett Lines
Authors: Wheeler Adam J. , Casey Andrew R. , Abruzzo Matthew W. 
Published: January 2024

Abstract
We describe several updates to Korg, a package for 1D LTE spectral synthesis of FGKM stars. Built-in functions to fit observed spectra via synthesis or equivalent widths make it easy to take advantage of Korg's automatic differentiation. Comparison to a past analysis of 18 Sco shows that we obtain significantly reduced line-to-line abundance scatter with Korg. Fitting and synthesis are facilitated by a rigorously tested model atmosphere interpolation method, which introduces negligible error to synthesized spectra for stars with T
eff ≳ 4000 K. For cooler stars, atmosphere interpolation is complicated by the presence of molecules, though we demonstrate an adequate method for cool dwarfs. The chemical equilibrium solver has been extended to include polyatomic and charged molecules, extending Korg's regime of applicability to M stars. We also discuss a common oversight regarding the synthesis of hydrogen lines in the infrared, and show that Korg's Brackett line profiles are a much closer match to observations than others available. Documentation, installation instructions, and tutorials are available at https://github.com/ajwheeler/Korg.jl.
Probing the Subparsec Dust of a Supermassive Black Hole with the Tidal Disruption Event AT 2020mot
Authors: Newsome Megan , Arcavi Iair , Howell D. Andrew , Burke Jamison , De Kishalay , Dgany Yael , Faris Sara , Farah Joseph , Hiramatsu Daichi , McCully Curtis , Padilla-Gonzalez Estefania , Pellegrino Craig , Terreran Giacomo 
Published: January 2024

Abstract
AT 2020mot is a typical UV/optical tidal disruption event (TDE) with no radio or X-ray signatures in a quiescent host. We find an i-band excess and rebrightening along the decline of the light curve which could be due to two consecutive dust echoes from the TDE. We model our observations following van Velzen et al. and find that the near-infrared light curve can be explained by concentric rings of thin dust within ∼0.1 pc of a ∼6 × 106
M
⊙ supermassive black hole (SMBH), among the smallest scales at which dust has been inferred near SMBHs. We find dust covering factors of order f

c
≤ 2%, much lower than found for dusty tori of active galactic nuclei. These results highlight the potential of TDEs for uncovering the environments around black holes when including near-infrared observations in high-cadence transient studies.
Are Coronal Loops Projection Effects?
Authors: Uritsky Vadim M. , Klimchuk James A. 
Published: January 2024

Abstract
We report results of an in-depth numerical investigation of three-dimensional projection effects that could influence the observed loop-like structures in an optically thin solar corona. Several archetypal emitting geometries are tested, including collections of luminous structures with circular cross sections of fixed and random size, and light-emitting structures with highly anisotropic cross sections, as well as two-dimensional stochastic current density structures generated by fully developed magnetohydrodynamic turbulence. A comprehensive set of statistical signatures is used to compare the line-of-sight (LOS) integrated emission signals predicted by the constructed numerical models with the loop profiles observed by the extreme ultraviolet telescope on board the flight 2.1 of the High-Resolution Coronal Imager (Hi-C). The results suggest that typical cross-sectional emission envelopes of the Hi-C loops are unlikely to have high eccentricity, and that the observed loops cannot be attributed to randomly oriented quasi-two-dimensional emitting structures, some of which would produce anomalously strong optical signatures due to an accidental LOS alignment, as expected in the ''coronal veil“ scenario proposed recently by Malanushenko et al. The possibility of apparent loop-like projections of very small (close to the resolution limit) or very large (comparable with the size of an active region) light-emitting sheets remains open, but the intermediate range of scales commonly associated with observed loop systems is most likely filled with true quasi-one-dimensional (roughly axisymmetric) structures embedded into the three-dimensional coronal volume.
Lyα Absorption in a “Croissant-like” Heliosphere
Authors: Powell Erick , Opher Merav , Kornbleuth Marc Z. , Baliukin Igor , Michael Adam T. , Wood Brian E. , Izmodenov Vladislav , Toth Gabor , Tenishev Valeriy 
Published: January 2024

Abstract
Lyα absorption profiles have been used to detect astrospheres and heliospheric absorption from the hydrogen wall and heliotail. Using magnetohydrodynamic models of the heliosphere, we can compare simulated to observed Lyα profiles to probe the neutral hydrogen within and near the heliosphere. There is an ongoing controversy whether the heliosphere has a long “comet-like” tail or a short “croissant-like” tail. Here we present the first Lyα absorption investigation using a croissant-like heliosphere. With identical boundary conditions we compare the BU model, which presents a croissant-like tail, and the Moscow model, which presents a comet-like tail. The BU and Moscow models present nearly identical Lyα profiles toward nose targets (α Cen and 36 Oph). Differences in Lyα profiles are shown toward the tail target (HD 35296). Despite the shortened heliotail of the croissant model, significant downwind heliosheath absorption is seen, just 5% shallower and shifted by 4 km s−1. This implies that an extended tail model is not required to reproduce the heliosheath Lyα absorption observations. Finer observation gratings may be able to resolve this shift. Additionally, when using higher interstellar medium (ISM) neutral and plasma densities and lower magnetic field (∣B
LISM∣ = 3.2 μG, α
BV ≈ 40°) than in the Moscow model, we find better agreement with observed Lyα profiles. None of the models presented show agreement in all directions simultaneously. Furthermore, we show that for the ISM conditions with the least certainty (n
p,LISM, n
H,LISM, T
LISM, B
LISM), B
LISM has the most significant effect on the structure of the hydrogen wall and Lyα profiles.
VaDAR: Varstrometry for Dual AGN Using Radio Interferometry
Authors: Schwartzman Emma , Clarke Tracy E. , Nyland Kristina , Secrest Nathan J. , Pfeifle Ryan W. , Schmitt Henrique , Satyapal Shobita , Rothberg Barry 
Published: January 2024

Abstract
Binary and dual active galactic nuclei (AGNs) are an important observational tool for studying the formation and dynamical evolution of galaxies and supermassive black holes. An entirely new method for identifying possible AGN pairs makes use of the exquisite positional accuracy of Gaia to detect astrometrically variable quasars, in tandem with the high spatial resolution of the Karl G. Jansky Very Large Array (VLA). We present a new pilot study of radio observations of 18 quasars (0.8 ≤ z ≤ 2.9), selected from the Sloan Digital Sky Survey DR16Q and matched with the Gaia DR3. All 18 targets are identified by their excess astrometric noise in Gaia. We targeted these 18 quasars with the VLA at 2–4 GHz (S band) and 8–12 GHz (X band), providing resolutions of 0.″65 and 0.″2, respectively, in order to constrain the origin of this variability. We combine these data with ancillary radio survey data and perform radio spectral modeling. The new observations are used to constrain the driver of the excess astrometric noise. We find that ∼44% of the target sample is likely to be either candidate dual AGN or gravitationally lensed quasars. Ultimately, we use this new strategy to help identify and understand this sample of astrometrically variable quasars, demonstrating the potential of this method for systematically identifying kiloparsec-scale dual quasars.
Monte Carlo Stellar Dynamics near Massive Black Holes: Two-dimensional Fokker–Planck Solutions of Multiple Mass Components
Authors: Zhang Fupeng , Amaro Seoane Pau 
Published: January 2024

Abstract
In this study we present a novel Monte Carlo code, referred to as GNC, which enables the investigation of dynamical relaxation in clusters comprising multiple mass components in the vicinity of supermassive black holes at the centers of galaxies. Our method is based on two-dimensional Fokker–Planck equations in the energy and angular momentum space, and allows the evolution of multiple mass components, including stars and compact objects. The code demonstrates remarkable flexibility in incorporating additional complex dynamics. By employing a weighting method, we effectively enhance the statistical accuracy of rare particle results. In this initial publication, we present the fundamental version of our method, focusing on two-body relaxations and loss cone effects. Through comparisons with previous studies, we establish consistent outcomes in terms of relaxation processes, energy and angular momentum distributions, density profiles, and loss cone consumption rates. We consistently observe the development of tangential anisotropy within the cluster, while the outer regions tend to retain near-isotropic characteristics. GNC holds great promise for exploring a wide range of intriguing phenomena within galactic nuclei, including relativistic stellar dynamics, providing detailed and insightful outcomes.
Enhanced Three-minute Oscillation above a Sunspot during a Solar Flare
Authors: Wang Ya , Fletcher Lyndsay , Mulay Sargam , Ji Haisheng , Cao Wenda 
Published: January 2024

Abstract
Three-minute oscillations are a common phenomenon in the solar chromosphere above a sunspot. Oscillations can be affected by the energy release process related to solar flares. In this paper, we report on an enhanced oscillation in flare event SOL2012-07-05T21:42 with a period of around 3 minutes that occurred at the location of a flare ribbon at a sunspot umbral–penumbral boundary and was observed in both chromospheric and coronal passbands. An analysis of this oscillation was carried out using simultaneous ground-based observations from the Goode Solar Telescope at the Big Bear Solar Observatory and space-based observations from the Solar Dynamics Observatory. A frequency shift was observed before and after the flare, with the running penumbral wave that was present with a period of about 200 s before the flare coexisting with a strengthened oscillation with a period of 180 s at the same locations after the flare. We also found a phase difference between different passbands, with the oscillation occurring from high-temperature to low-temperature passbands. Theoretically, the change in frequency was strongly dependent on the variation of the inclination of the magnetic field and the chromospheric temperature. Following an analysis of the properties of the region, we found the frequency change was caused by a slight decrease of the magnetic inclination angle with respect to the local vertical. In addition, we suggest that the enhanced 3 minute oscillation was related to the additional heating, maybe due to the downflow, during the EUV late phase of the flare.
Using the Two-point Correlation Function to Understand the Assembly Histories of Milky Way–like Galaxies
Authors: Zhang Yike , Wang Wenting , Han Jiaxin , Yang Xiaohu , Rodriguez-Gomez Vicente , Palau Carles G. , Tan Zhenlin 
Published: January 2024

Abstract
The two-point correlation function (2PCF) is a powerful statistical tool to measure galaxy clustering. Although 2PCF has also been used to study the clustering of stars on subparsec to kiloparsec scales, its physical implication is not clear. In this study, we use the Illustris-TNG50 simulation to study the connection between the 2PCF of accreted halo stars and the assembly histories of Milky Way-mass galaxies. We find, in general, that the 2PCF signal increases with the increase in galactocentric radii, r, and with the decrease in the pair separations. Galaxies that assemble late on average have stronger 2PCF signals. With z
1/4, z
1/2, and z
3/4 defined as the redshifts when galaxies accreted one-fourth, half, and three-fourths of their ex situ stellar mass today, we find they all show the strongest correlations with the 2PCF signals at r < ∼ 0.2R
200. z
3/4 shows the strongest correlations than those of z
1/4 or z
1/2. However, the correlations have large scatters. The 2PCFs in the velocity space show weaker correlations with the galaxy formation times within ∼0.35R
200 than real-space 2PCFs, and the scatter is considerably large. Both the real- and velocity-space 2PCFs correlate with the assembly histories of the host dark matter halos as well. Within 0.3R
200, the real-space 2PCF shows stronger correlations with the galaxy formation histories than with the halo formation histories. We conclude that it is difficult to use 2PCF alone to precisely predict the formation times or assembly histories of galaxies.
Evolution and Final Fate of Solar Metallicity Stars in the Mass Range 7–15 M
⊙. I. The Transition from Asymptotic Giant Branch to Super-AGB Stars, Electron Capture, and Core-collapse Supernova Progenitors
Authors: Limongi Marco , Roberti Lorenzo , Chieffi Alessandro , Nomoto Ken’ichi 
Published: January 2024

Abstract
According to a standard initial mass function, stars in the range 7–12 M
⊙ constitute ∼50% (by number) of the stars more massive than ∼7 M
⊙, but in spite of this, their evolutionary properties, and in particular their final fate, are still scarcely studied. In this paper, we present a detailed study of the evolutionary properties of solar metallicity nonrotating stars in the range 7–15 M
⊙, from the pre-main-sequence phase up to the presupernova stage or an advanced stage of the thermally pulsing phase, depending on the initial mass. We find that (1) the 7.00 M
⊙ star develops a degenerate CO core and evolves as a classical asymptotic giant branch (AGB) star in the sense that it does not ignite the C-burning reactions, (2) stars with initial mass M ≥ 9.22 M
⊙ end their lives as core-collapse supernovae, (3) stars in the range 7.50 ≤ M/M
⊙ ≤ 9.20 develop a degenerate ONeMg core and evolve through the thermally pulsing super-AGB phase, (4) stars in the mass range 7.50 ≤ M/M
⊙ ≤ 8.00 end their lives as hybrid CO/ONeMg or ONeMg WDs, and (5) stars with initial mass in the range 8.50 ≤ M/M
⊙ ≤ 9.20 may potentially explode as electron-capture supernovae.
Starburst-induced Gas–Star Kinematic Misalignment
Authors: Cenci Elia , Feldmann Robert , Gensior Jindra , Bullock James S. , Moreno Jorge , Bassini Luigi , Bernardini Mauro 
Published: January 2024

Abstract
A kinematic misalignment of the stellar and gas components is a phenomenon observed in a significant fraction of galaxies. However, the underlying physical mechanisms are not well understood. A commonly proposed scenario for the formation of a misaligned component requires any preexisting gas disk to be removed, via flybys or ejective feedback from an active galactic nucleus. In this Letter, we study the evolution of a Milky Way mass galaxy in the FIREbox cosmological volume that displays a thin, counterrotating gas disk with respect to its stellar component at low redshift. In contrast to scenarios involving gas ejection, we find that preexisting gas is mainly removed via the conversion into stars in a central starburst, triggered by a merging satellite galaxy. The newly accreted, counterrotating gas eventually settles into a kinematically misaligned disk. About 4% (8 out of 182) of FIREbox galaxies with stellar masses larger than 5 × 109
M
⊙ at z = 0 exhibit gas–star kinematic misalignment. In all cases, we identify central starburst-driven depletion as the main reason for the removal of the preexisting corotating gas component, with no need for feedback from, e.g., a central active black hole. However, during the starburst, the gas is funneled toward the central regions, likely enhancing black hole activity. By comparing the fraction of misaligned discs between FIREbox and other simulations and observations, we conclude that this channel might have a non-negligible role in inducing kinematic misalignment in galaxies.
Goodwill : un retour vers le futur ? Simulation des effets attendus d’un retour vers un amortissement systématique
Authors: Bessieux-Ollier Corinne , Blum Véronique , Walliser Élisabeth 
Published: January 2024

Le document de travail DP/2020/1 « regroupements d’entreprises » émis par l’IASB questionne le choix fait il y a deux décennies de supprimer l’amortissement du goodwill et de le remplacer par un test de dépréciation annuel. Nous proposons une simulation permettant d’étudier les effets d’un changement de méthode comptable avec un retour vers l’amortissement systématique du goodwill pour un échantillon de 57 entreprises issues du SBF 120. Nos résultats indiquent une détérioration importante de la performance et de la structure financières des entreprises.
Provisionnement par l’approche des pertes de crédit attendues et réduction de la procyclicité
Authors: Dao-Le Flécher Phu , Paget-Blanc Eric 
Published: January 2024

L’article vise à déterminer si les nouvelles règles de provision permettent de réduire le caractère procyclique des provisions, en se fondant sur la crise de la Covid-19. La discrétion accrue en matière de provision a été exacerbée par les mesures prises par les régulateurs pour limiter l’impact de la crise. À partir d’un échantillon de 94 banques européennes et américaines cotées, nous constatons qu’en 2020, les encours à risque ont diminué et les dépréciations pour risque de crédit n’ont que légèrement augmenté en Europe, malgré la diminution sensible du PIB. Nous concluons que la norme IFRS 9, fondée sur l’approche par les pertes de crédit attendues et associée à des mesures d’assouplissement réglementaires en période de crise, permet de réduire la procyclicité des provisions.
Marseille face à la peste
Authors: Vigié Marc 
Published: January 2024

Comme la guerre, l’épidémie est pour une société un moment de vérité. Elle tue, beaucoup et sans distinction. Son assaut brutal suspend le cours de l’ordinaire, confronte les croyances aux connaissances, teste la robustesse et la résilience des structures politiques, sociales, économiques, morales et culturelles. Elle exige une réaction collective. Surtout, elle pose une question essentielle : comment la vaincre ? L’exemple de la peste qui ravage Marseille et la Provence entre 1720 et 1722 le montre.
Qu’est-ce que vaincre dans une perspective monothéiste ?
Authors: Hanne Olivier 
Published: January 2024

Les trois monothéismes formalisent différemment la dynamique qui conduit à la victoire : profondément éthique dans le judaïsme, nécessairement spirituelle dans le christianisme, multiforme dans l’islam. Pourtant, chaque mouvement religieux a su adapter, et parfois trahir, ses textes sacrés pour répondre aux circonstances historiques, sans jamais négliger l’idée d’un inachèvement de toute victoire dans le temps et dans l’Histoire.
OTAN. Gagner ou vaincre selon les différents alliés
Authors: Bathurst Ben , Fernández Sánchez Javier , Giacomin Dario , Goisque Jérôme 
Published: January 2024

Quatre généraux alliés, siégeant côte à côte au sein du comité militaire de l’ otan , se sont prêtés au jeu d’une définition du mot « vaincre ». Loin des définitions académiques, leur analyse révèle le caractère profondément paradoxal de cette notion. Finalement, qu’est-ce que vaincre ?
Vaincre ou rallier les Marocains : le dilemme de la France au temps de la conquête
Authors: Rivet Daniel 
Published: January 2024

Quelle méthode employer pour conquérir le Maroc et l’intégrer à l’empire que la iii e République est en train de fonder ? Telle est la question qui divise la France coloniale au début du xx e siècle. Faut-il, par une politique des tribus, croquées l’une après l’autre, recourir exclusivement à la manière forte des militaires, ou bien faut-il procéder par en haut, en satellisant l’État marocain en prenant appui sur le sultan et sur son appareillage étatique encore embryonnaire, à l’instar du protectorat tunisien réalisé en 1881, comme le soutiennent les diplomates et les financiers ?
La royauté française dans la guerre de Cent Ans : une victoire inéluctable ?
Authors: Hélary Xavier 
Published: January 2024

Comment Charles VII a-t-il réussi à vaincre l’ennemi anglais ? Au début de l’année 1429, rien n’était joué. Et si Jeanne d’Arc a fait pencher la balance de son côté, il est possible que, même si elle n’avait pas été là, les choses auraient quand même tourné en sa faveur. C’est peut-être que la victoire finale de la royauté française ne s’est pas jouée uniquement dans les batailles. Comment l’expliquer ? Deux personnalités, qui incarnent chacune à sa façon le courage malheureux, vont nous y aider : Jean le Bon et Jeanne d’Arc.
Peut-on encore rendre les honneurs à un vaincu ?
Authors: Jordan Frédéric 
Published: January 2024

Les coutumes de la guerre, comme celle de rendre les honneurs au vaincu, semblent aujourd’hui s’effacer. Faut-il donc accepter de voir ces pratiques disparaître sous prétexte que le champ de bataille aurait changé de nature au regard des engagements de plus en plus complexes auxquels nous sommes confrontés ? Il s’agit de démontrer que nos soldats doivent continuer de se les approprier pour pouvoir vaincre.
Vaincre sans humilier
Authors: Abel Olivier 
Published: January 2024

Peut-on vaincre sans humilier ? La loi de la force, qui impose à l’autre l’obligation de se mesurer ou de disparaître, est barbare, et abandonne tôt ou tard les vainqueurs eux-mêmes. Comment mener la guerre en sachant qu’on ne sera pas toujours victorieux, et de manière à ce que la paix soit encore ensuite un jour possible ? La force victorieuse est écrasante et dévastatrice par les passions terribles qu’elle déchaîne, car on hait et on méprise ceux à qui on a fait du mal, et les puissances de la vengeance sont insatiables. Il s’agit ici de comprendre à quelles conditions elles pourraient être apaisées.
Instruire pour vaincre. Une somme de « petits riens »
Authors: Erbland Brice , Garin Laurent , Marteau Jordan , Cotard Jean-Luc 
Published: January 2024

« Ils s’instruisent pour vaincre » est la célèbre devise de l’École spéciale militaire de Saint-Cyr qui accompagne les élèves-officiers de l’armée de terre depuis plus de deux siècles. Elle mérite que l’on s’y attarde. C’est ce que font ici le colonel Erbland, aujourd’hui à la tête du premier bataillon de saint-cyriens, et ses deux adjoints, en charge, entre autres, de ce qui ne peut réellement être décrit dans un inventaire de formation : l’éducation au savoir-être militaire. C’est pourtant dans cet aspect essentiel et difficilement normalisable que se trouve l’enseignement de l’esprit permettant d’aller jusqu’au bout et de vaincre.