bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Central Star of NGC 2346 as a Clue to Binary Evolution through the Common Envelope Phase
Authors: Gómez-Muñoz M. A. , Manchado A. , Bianchi L. , Manteiga M. , Vázquez R. 
Published: November 2019

Abstract
We present an analysis of the binary central star of the planetary nebula NGC 2346 based on archival data from the International Ultraviolet Explorer, and new low- and high-resolution optical spectra (3700–7300 Å). By including in the spectral analysis the contribution of both stellar and nebular continuum, we reconciled long-time discrepant UV and optical diagnostics and derive E(B–V) = 0.18 ± 0.01. We reclassified the companion star as A5IV by analyzing the wings of the Balmer absorption lines in the high-resolution (R = 67,000) optical spectra. Using the distance to the nebula of 1400 pc from Gaia DR2, we constructed a photoionization model based on abundances and line intensities derived from the low-resolution optical spectra, and obtained a temperature of T
eff = 130,000 K and a luminosity of L = 170 L
⊙ for the ionizing star, consistent with the UV continuum. This analysis allows us to better characterize the binary system’s evolution. We conclude that the progenitor star of NGC 2346 has experienced a common envelope phase, in which the companion star has accreted mass and evolved off the main-sequence.
Evolution of the Three-dimensional Shape of Passively Evolving and Star-forming Galaxies at z < 1
Authors: Satoh Yuki K. , Kajisawa Masaru , Himoto Kazuharu G. 
Published: November 2019

Abstract
Using the HST/ACS I
F814W-band data, we investigated the distribution of apparent axial ratios of ∼21,000 galaxies with M

V
< −20 at 0.2 < z < 1.0 in the COSMOS field as a function of stellar mass, specific star formation rate (sSFR), and redshift. We statistically estimated intrinsic 3D shapes of these galaxies by fitting the axial-ratio distribution with triaxial ellipsoid models characterized by face-on (middle-to-long) and edge-on (short-to-long) axial ratios B/A and C/A. We found that the transition from thin disk to thick spheroid occurs at ΔMS ∼ −1 dex, i.e., 10 times lower sSFR than that of the main sequence for galaxies with M
star = 1010–1011
M
⊙ at 0.2 < z < 1.0. Furthermore, the intrinsic thickness (C/A) of passively evolving galaxies with M
star = 1010–1011
M
⊙ significantly decreases with time from C/A ∼ 0.40–0.50 at z ∼ 0.8 to C/A ∼ 0.33–0.37 at z ∼ 0.4, while those galaxies with M
star > 1011
M
⊙ have C/A ∼ 0.5 irrespective of redshift. On the other hand, star-forming galaxies on the main sequence with 109.5–1011
M
⊙ show no significant evolution in their shape at 0.2 < z < 1.0, but their thickness depends on stellar mass; more massive star-forming galaxies tend to have lower C/A (thinner shape) than low-mass ones. These results suggest that some fraction of star-forming galaxies with a thin disk, which started to appear around z ∼ 1, quench their star formation without violent morphological change, and these newly added quiescent galaxies with a relatively thin shape cause the significant evolution in the axial-ratio distribution of passively evolving galaxies with M
star < 1011
M
⊙ at z < 1.
Global 3D Hydrodynamic Modeling of In-transit Lyα Absorption of GJ 436b
Authors: Khodachenko M. L. , Shaikhislamov I. F. , Lammer H. , Berezutsky A. G. , Miroshnichenko I. B. , Rumenskikh M. S. , Kislyakova K. G. , Dwivedi N. K. 
Published: October 2019

Abstract
Using a global 3D, fully self-consistent, multifluid hydrodynamic model, we simulate the escaping upper atmosphere of the warm Neptune GJ 436b, driven by the stellar X-ray and ultraviolet (XUV) radiation impact and gravitational forces and interacting with the stellar wind. Under the typical parameters of XUV flux and stellar wind plasma expected for GJ 436, we calculate in-transit absorption in Lyα and find that it is produced mostly by energetic neutral atoms outside of the planetary Roche lobe, due to the resonant thermal line broadening. At the same time, the influence of radiation pressure has been shown to be insignificant. The modeled absorption is in good agreement with the observations and reveals such features as strong asymmetry between blue and red wings of the absorbed Lyα line profile, deep transit depth in the high-velocity blue part of the line reaching more than 70%, and the timing of early ingress. On the other hand, the model produces significantly deeper and longer egress than in observations, indicating that there might be other processes and factors, still not accounted for, that affect the interaction between the planetary escaping material and the stellar wind. At the same time, it is possible that the observational data, collected in different measurement campaigns, are affected by strong variations of the stellar wind parameters between the visits, and therefore they cannot be reproduced altogether with the single set of model parameters.
The Galilean Satellites Formed Slowly from Pebbles
Authors: Shibaike Yuhito , Ormel Chris W. , Ida Shigeru , Okuzumi Satoshi , Sasaki Takanori 
Published: November 2019

Abstract
It is generally accepted that the four major (Galilean) satellites formed out of the gas disk that accompanied Jupiter’s formation. However, understanding the specifics of the formation process is challenging, as both small particles (pebbles) and the satellites are subject to fast migration processes. Here we hypothesize a new scenario for the origin of the Galilean system, based on the capture of several planetesimal seeds and subsequent slow accretion of pebbles. To halt migration, we invoke an inner disk truncation radius, and other parameters are tuned for the model to match physical, dynamical, compositional, and structural constraints. In our scenario it is natural that Ganymede’s mass is determined by pebble isolation. Our slow pebble accretion scenario then reproduces the following characteristics: (1) the mass of all the Galilean satellites; (2) the orbits of Io, Europa, and Ganymede captured in mutual 2:1 mean motion resonances; (3) the ice mass fractions of all the Galilean satellites; and (4) the unique ice-rock partially differentiated Callisto and the complete differentiation of the other satellites. Our scenario is unique to simultaneously reproduce these disparate properties.
First Observation of the Solar Type III Burst Decay and Its Interpretation
Authors: Melnik V. N. , Konovalenko A. A. , Yerin S. M. , Bubnov I. M. , Brazhenko A. I. , Frantsuzenko A. V. , Dorovskyy V. V. , Shevchuk M. V. , Rucker H. O. 
Published: November 2019

Abstract
The decay of a Type III burst into two Type III bursts was registered during solar observations by GURT and URAN-2 radio telescopes on 2017 April 18. This was the first time such a phenomenon was observed. Newborn Type III bursts have drift rates smaller than that of a decaying Type III burst. Such decays of Type III bursts were predicted by a gas-dynamic theory of high-energy electron beams propagating through the thermal background plasma. In the frame of this theory Type III sources are beam-plasma structures moving with constant velocities. In our case the sum of velocities of newborn Type III sources equals the velocity of a decaying Type III source. The last one is 0.33c in the case of fundamental radio emission and 0.2c at the harmonic radio emission of a Type III burst. The density ratio of slow and fast newborn Type III sources is about 3.
Confirmation of Planet-mass Objects in Extragalactic Systems
Authors: Bhatiani Saloni , Dai Xinyu , Guerras Eduardo 
Published: November 2019

Abstract
Quasar microlensing serves as a unique probe of discrete objects within galaxies and galaxy clusters. Recent advancement of the technique shows that it can constrain planet-scale objects beyond our native galaxy by studying their induced microlensing signatures, the energy shift of emission lines originating in the vicinity of the black hole of high redshift background quasars. We employ this technique to exert effective constraints on the planet-mass object distribution within two additional lens systems, Q J0158−4325 (z

l
= 0.317) and SDSS J1004+4112 (z

l
= 0.68), using Chandra observations of the two gravitationally lensed quasars. The observed variations of the emission line peak energy can be explained as microlensing of the FeKα emission region induced by planet-mass microlenses. To corroborate this, we perform microlensing simulations to determine the probability of a caustic transiting the source region and compare this with the observed line shift rates. Our analysis yields constraints on the substellar population, with masses ranging from Moon (10−8
M
⊙) to Jupiter (10−3
M
⊙) sized bodies, within these galaxy or cluster scale structures, with total mass fractions of ∼3 × 10−4 and ∼1 × 10−4 with respect to halo mass for Q J0158−4325 and SDSS J1004+4112, respectively. Our analysis suggests that unbound planet-mass objects are universal in galaxies, and we surmise the objects to be either free-floating planets or primordial black holes. We present the first ever constraints on the substellar mass distribution in the intracluster light of a galaxy cluster. Our results provide the most stringent limit on the mass fraction of primordial black holes at the mass range.
Including Dust Coagulation in Hydrodynamic Models of Protoplanetary Disks: Dust Evolution in the Vicinity of a Jupiter-mass Planet
Authors: Dra̧żkowska Joanna , Li Shengtai , Birnstiel Til , Stammler Sebastian M. , Li Hui 
Published: November 2019

Abstract
Dust growth is often neglected when building models of protoplanetary disks due to its complexity and computational expense. However, it does play a major role in shaping the evolution of protoplanetary dust and planet formation. In this paper, we present a numerical model coupling 2D hydrodynamic evolution of a protoplanetary disk, including a Jupiter-mass planet, and dust coagulation. This is obtained by including multiple dust fluids in a single grid-based hydrodynamic simulation and solving the Smoluchowski equation for dust coagulation on top of solving for the hydrodynamic evolution. We find that fragmentation of dust aggregates trapped in a pressure bump outside of the planetary gap leads to an enhancement in the density of small grains. We compare the results obtained from the full-coagulation treatment to the commonly used, fixed-dust-size approach and to previously applied, less computationally intensive methods for including dust coagulation. We find that the full-coagulation results cannot be reproduced using the fixed-size treatment, but some can be mimicked using a relatively simple method for estimating the characteristic dust size in every grid cell.
Influence of Wolf–Rayet Stars on Surrounding Star-forming Molecular Clouds
Authors: Baug T. , Grijs Richard de , Dewangan L. K. , Herczeg Gregory J. , Ojha D. K. , Wang Ke , Deng Licai , Bhatt B. C. 
Published: October 2019

Abstract
We investigate the influence of Wolf–Rayet (W-R) stars on their surrounding star-forming molecular clouds. We study five regions containing W-R stars in the inner Galactic plane (l ∼ [14°–52°]), using multiwavelength data from near-infrared to radio wavelengths. Analysis of 13CO line data reveals that these W-R stars have developed gas-deficient cavities in addition to molecular shells with expansion velocities of a few kilometers per second. The pressure owing to stellar winds primarily drives these expanding shells and sweeps up the surrounding matter to distances of a few parsecs. The column densities of shells are enhanced by a minimum of 14% for one region to a maximum of 88% for another region with respect to the column densities within their central cavities. No active star formation—including molecular condensations, protostars, or ionized gas—is found inside the cavities, whereas such features are observed around the molecular shells. Although the expansion of ionized gas is considered an effective mechanism to trigger star formation, the dynamical ages of the H ii regions in our sample are generally not sufficiently long to do so efficiently. Overall, our results hint at the possible importance of negative W-R wind-driven feedback on the gas-deficient cavities, where star formation is quenched as a consequence. In addition, the presence of active star formation around the molecular shells indicates that W-R stars may also assist in accumulating molecular gas, and that they could initiate star formation around those shells.
Demographics of Planetesimals Formed by the Streaming Instability
Authors: Li 李日 Rixin 新 , Youdin Andrew N. , Simon Jacob B. 
Published: October 2019

Abstract
The streaming instability (SI) is a mechanism to aerodynamically concentrate solids in protoplanetary disks and facilitate the formation of planetesimals. Recent numerical modeling efforts have demonstrated the increasing complexity of the initial mass distribution of planetesimals. To better constrain this distribution, we conduct SI simulations including self-gravity with the highest resolution hitherto. To subsequently identify all of the self-bound clumps, we develop a new clump-finding tool, Planetesimal Analyzer. We then apply a maximum likelihood estimator to fit a suite of parameterized models with different levels of complexity to the simulated mass distribution. To determine which models are best-fitting and statistically robust, we apply three model selection criteria with different complexity penalties. We find that the initial mass distribution of clumps is not universal regarding both the functional forms and parameter values. Our model selection criteria prefer models different from those previously considered in the literature. Fits to multi-segment power-law models break to a steeper distribution above masses close to those of 100 km collapsed planetesimals, similar to observed size distributions in the Kuiper Belt. We find evidence for a turnover at the low-mass end of the planetesimal mass distribution in our high-resolution run. Such a turnover is expected for gravitational collapse, but had not previously been reported.
Thermal Components in Gamma-Ray Bursts. I. How Do They Affect Nonthermal Spectral Parameters?
Authors: Li Liang 
Published: November 2019

Abstract
The spectral components of the prompt emission of gamma-ray bursts (GRBs) mainly consist of two possible origins: synchrotron (nonthermal) and photosphere (thermal). The typical spectral properties of GRBs can be modeled by a dominant nonthermal component (a Band-like function or cutoff power law), while some of them have an additional thermal component (a Planck-like function). In this paper, we investigate the effects of thermal components on the nonthermal spectral parameters. We focus on eight Fermi Gamma-ray Burst Monitor bursts of which the spectra deviate from a Band-only function, and the thermal components are significant. We sort them into thermal-subdominant Group I (e.g., GRB 110721A) and thermal-dominant Group II (e.g., GRB 090902B). Several interesting results are found assuming the spectral component is totally attributed to the nonthermal component: (i) the low-energy photon index α becomes harder; (ii) the peak energy E
c is significantly smaller and lies between the peak temperature of blackbody component and the peak energy of the cutoff power law + blackbody (CPL+BB) model; (iii) total flux F is generally the same; (iv) the changes (Δα and ΔE
c) are positively correlated with the ratio between the thermal flux and total flux; and (v) parameter relations (F–α, F–E
c, and E
c–α) also changed prominently. The GRBs in both groups show the same results. Our analysis indicates that the thermal component is important, and it significantly affects the spectral parameters and the consequential physical interpretations.
L’observation socio-territoriale par les acteurs du secteur social : catégories d’analyse et choix méthodologiques
Authors: Terrier Eugénie 
Published: October 2019

La territorialisation de l’action sociale en France a favorisé le développement de l’analyse spatiale des réalités sociales locales. Cet article s’intéresse à la manière dont l’observation des territoires est actuellement abordée au sein des institutions de l’action sociale. Il s’agit de mieux comprendre les approches théoriques et méthodologiques qui sont actuellement privilégiées par différents acteurs du secteur social : qu’ils soient spécialistes de l’observation sociale locale, cadres de l’action sociale ou travailleurs sociaux. Cette réflexion s’appuie sur les résultats de plusieurs recherches-actions menées avec des départements. L’évaluation des travaux existants au sein des collectivités et au niveau national montre une prédominance de l’approche statistique et cartographique des données socio-économiques.
Être hébergé en famille dans une structure sociale : des interventions qui varient selon les espaces de vie
Authors: Ganne Claire , Thiery Nathalie 
Published: October 2019

Les établissements sociaux qui hébergent des familles sans logement proposent des conditions d’hébergement très variées, de l’institution collective à l’hébergement en appartement autonome. De plus, ils relèvent de différents secteurs des politiques sociales. Si les centres d’hébergement et de réinsertion sociale, qu’ils soient collectifs ou « diffus », visent prioritairement l’accès au logement, les centres maternels (souvent collectifs) et les centres parentaux, de création plus récente et fonctionnant davantage en logement diffus, s’inscrivent dans le dispositif de la protection de l’enfance. En se basant sur trois recherches menées auprès de personnes hébergées dans ces différentes structures, cet article a pour objectif d’explorer l’articulation entre l’agencement spatial des espaces de vie et les pratiques d’interventions sociales en direction des familles, en fonction des missions de l’institution.
Interpréter le domicile, évaluer le danger. Les visites à domicile dans le champ de la protection de l’enfance
Authors: Léon Stéphane , Rey Claudie 
Published: October 2019

Le domicile constitue à la fois le refuge de la vie privée et une catégorie de l’action sociale. Espace ambivalent, il situe les travailleurs sociaux entre le contrôle et l’aide, entre la contrainte légale et l’accompagnement. Ces notions posent la question de leur mise en œuvre dans un contexte législatif qui oscille entre respect de la vie privée et obligation légale de protection de l’enfance. Le domicile est un support à l’évaluation des travailleurs sociaux dans le cadre de la protection de l’enfance : il permet de mesurer le danger et d’envisager les réponses possibles dans un cadre juridique. Cependant, ce cadre ne suffit pas à construire la relation avec les familles. Les travailleurs sociaux sont amenés à négocier leur place au sein du domicile des familles, la lecture de cet espace de l’intime étant indispensable à l’évaluation du danger que les enfants rencontrent ou peuvent rencontrer.
Le Cinématographe dans le mouvement :une métaphysique des feuilles
Authors: Albera François 
Published: October 2019

La réception du Cinématographe Lumière à son émergence suggère qu’avec lui s’institue une distinction entre deux types de mouvement : celui des figures (qui a été jusqu’ici analysé et reconstitué par les jouets optiques, la chronophotographie et les bandes du kinétoscope) et celui du fond qui demeurait jusque là indifférencié, neutre et devient, avec les Lumière, un milieu. L’anecdote reprise par Méliès du mouvement des feuilles des arbres dans le vent semble ainsi désigner un phénomène qui est celui de la captation/restitution des micro-mouvements de la matière, l’aérien, rendant tangible l’insaisissable éther. L’hypothèse de cette étude est que le cinéma accompagne par là la refondation du monde physique par la science sur la base de la crise du modèle mécanique – que proclame Albert Einstein – que font éclater les évolutions de la thermodynamique, l’optique, l’électromagnétisme et la microphysique. Le point de jonction se situe dans les rapports entre ces phénomènes naturels aériens, de poussières, de fumées ou de feuilles innombrables avec l’activité de l’émulsion du film et ses cristaux d’halogénures d’argent.
Predicting Prolonged Intensive Care Unit Stay Among Patients With Sepsis-Induced Hypotension
Authors: Murphy David L. , Johnson Nicholas J. , Hall M. Kennedy , Kim Mitchell L. , Shapiro Nathan I. , Henning Daniel J. 
Published: November 2019

Background
Sepsis risk stratification tools typically predict mortality, although stays in the intensive care unit (ICU) of 24 hours or longer may be more clinically relevant for emergency department disposition.

Objective
To explore predictors of ICU stay of 24 hours or longer among infected, hypotensive emergency department patients.

Methods
A secondary analysis of 2 prospective, observational studies of adult patients with severe sepsis or an infection with a systolic blood pressure less than 90 mm Hg in 3 urban, academic emergency departments was performed. Patients with hypotension and infection were included. Patients with emergency department intubation, vasopressor administration, and/or death were excluded. The primary outcome was ICU stay of 24 hours or longer or death in less than 24 hours. Multivariable logistic regression was used to predict ICU stay of 24 hours or longer.

Results
Of 233 patients, 108 (46.4%) had ICU stays of 24 hours or longer. History of heart failure (odds ratio, 3.6; 95% CI, 1.5-8.3), bicarbonate level less than 20 mEq/L (odds ratio, 2.0; 95% CI, 1.1-3.8), respiratory rate greater than 20/min (odds ratio, 2.0; 95% CI, 1.1-3.7), and creatinine level greater than 2.0 mg/dL (odds ratio, 3.6; 95% CI, 1.9-6.7) were independent predictors of ICU stay of 24 hours or longer (area under curve, 0.74). The presence of 1 of these factors predicted ICU stay of 24 hours or longer (area under curve, 0.74) with 82.4% sensitivity and 49.6% specificity.

Conclusions
These exploratory results show that heart failure, bicarbonate level of less than 20 mEq/L, tachypnea, or creatinine level greater than 2.0 mg/dL increases the likelihood of an ICU stay of 24 hours or longer among infected, hypotensive emergency department patients.