bluuebunny/crossref_metadata_2025_split huggingface dataset:
A STUDY OF RO-VIBRATIONAL OH EMISSION FROM HERBIG Ae/Be STARS
Authors: Brittain Sean D. , Najita Joan R. , Carr John S. , Ádámkovics Máté , Reynolds Nickalas 
Published: October 2016

ABSTRACT
We present a study of ro-vibrational OH and CO emission from 21 disks around Herbig Ae/Be stars. We find that the OH and CO luminosities are proportional over a wide range of stellar ultraviolet luminosities. The OH and CO line profiles are also similar, indicating that they arise from roughly the same radial region of the disk. The CO and OH emission are both correlated with the far-ultraviolet luminosity of the stars, while the polycyclic aromatic hydrocarbon (PAH) luminosity is correlated with the longer wavelength ultraviolet luminosity of the stars. Although disk flaring affects the PAH luminosity, it is not a factor in the luminosity of the OH and CO emission. These properties are consistent with models of UV-irradiated disk atmospheres. We also find that the transition disks in our sample, which have large optically thin inner regions, have lower OH and CO luminosities than non-transition disk sources with similar ultraviolet luminosities. This result, while tentative given the small sample size, is consistent with the interpretation that transition disks lack a gaseous disk close to the star.
THE LOCAL BLACK HOLE MASS FUNCTION DERIVED FROM THE MBH–P AND THE MBH–n RELATIONS
Authors: Mutlu-Pakdil Burçin , Seigar Marc S. , Davis Benjamin L. 
Published: October 2016

ABSTRACT
We present a determination of the supermassive black hole (SMBH) mass function for early- and late-type galaxies in the nearby universe (z < 0.0057), established from a volume-limited sample consisting of a statistically complete collection of the brightest spiral galaxies in the southern hemisphere. The sample is defined by limiting luminosity (redshift-independent) distance, D

L
= 25.4 Mpc, and a limiting absolute B-band magnitude,

. These limits define a sample of 140 spiral, 30 elliptical (E), and 38 lenticular (S0) galaxies. We established the Sérsic index distribution for early-type (E/S0) galaxies in our sample. Davis et al. established the pitch angle distribution for their sample, which is identical to our late-type (spiral) galaxy sample. We then used the pitch angle and the Sérsic index distributions in order to estimate the SMBH mass function for our volume-limited sample. The observational simplicity of our approach relies on the empirical relation between the mass of the central SMBH and the Sérsic index for an early-type galaxy or the logarithmic spiral-arm pitch angle for a spiral galaxy. Our SMBH mass function agrees well at the high-mass end with previous values in the literature. At the low-mass end, although inconsistencies exist in previous works that still need to be resolved, our work is more in line with expectations based on modeling of black hole evolution.
SPATIAL DISTRIBUTION OF PAIR PRODUCTION OVER THE PULSAR POLAR CAP
Authors: Belyaev Mikhail A. , Parfrey Kyle 
Published: October 2016

ABSTRACT
Using an analytic, axisymmetric approach that includes general relativity, coupled to a condition for pair production deduced from simulations, we derive general results about the spatial distribution of pair-producing field lines over the pulsar polar cap. In particular, we show that pair production on magnetic field lines operates over only a fraction of the polar cap for an aligned rotator for general magnetic field configurations, assuming the magnetic field varies spatially on a scale that is larger than the size of the polar cap. We compare our result to force-free simulations of a pulsar with a dipole surface field and find excellent agreement. Our work has implications for first-principles simulations of pulsar magnetospheres and for explaining observations of pulsed radio and high-energy emission.
CONSTRAINING THE LIFETIME AND OPENING ANGLE OF QUASARS USING FLUORESCENT Lyα EMISSION: THE CASE OF Q0420–388
Authors: Borisova Elena , Lilly Simon J. , Cantalupo Sebastiano , Prochaska J. Xavier , Rakic Olivera , Worseck Gabor 
Published: October 2016

ABSTRACT
A toy model is developed to understand how the spatial distribution of fluorescent emitters in the vicinity of bright quasars could be affected by the geometry of the quasar bi-conical radiation field and by its lifetime. The model is then applied to the distribution of high-equivalent-width Lyα emitters (with rest-frame equivalent widths above 100 Å, threshold used in, e.g., Trainor & Steidel) identified in a deep narrow-band 36 × 36 arcmin2 image centered on the luminous quasar Q0420–388. These emitters are found near the edge of the field and show some evidence of an azimuthal asymmetry on the sky of the type expected if the quasar is radiating in a bipolar cone. If these sources are being fluorescently illuminated by the quasar, the two most distant objects require a lifetime of at least 15 Myr for an opening angle of 60° or more, increasing to more than 40 Myr if the opening angle is reduced to a minimum of 30°. However, some other expected signatures of boosted fluorescence are not seen at the current survey limits, e.g., a fall off in Lyα brightness, or equivalent width, with distance. Furthermore, to have most of the Lyα emission of the two distant sources to be fluorescently boosted would require the quasar to have been significantly brighter in the past. This suggests that these particular sources may not be fluorescent, invalidating the above lifetime constraints. This would cast doubt on the use of this relatively low equivalent width threshold and thus also on the lifetime analysis in Trainor and Steidel.
PROMPT RADIATION AND MASS OUTFLOWS FROM THE STREAM–STREAM COLLISIONS OF TIDAL DISRUPTION EVENTS
Authors: Jiang (姜燕飞) Yan-Fei , Guillochon James , Loeb Abraham 
Published: October 2016

ABSTRACT
Stream–stream collisions play an important role in the circularization of highly eccentric streams that result from tidal disruption events (TDEs). We perform three-dimensional radiation hydrodynamic simulations to show that stream collisions can contribute significant optical and ultraviolet light to the flares produced by TDEs, and can explain the majority of the observed emission. Our simulations focus on the region near the radiation-pressure-dominated shock produced by a collision and track how the kinetic energy of the stream is dissipated by the associated shock. When the mass flow rate of the stream

is a significant fraction of the Eddington accretion rate, ≳2% of the initial kinetic energy is converted to radiation as a result of the collision. In this regime, the collision redistributes the specific kinetic energy into the downstream gas and more than 16% of the mass can become unbound. The fraction of unbound gas decreases rapidly as

drops significantly below the Eddington limit, with no unbound gas being produced when

drops to 1% of Eddington; we find, however, that the radiative efficiency increases slightly to ≲8% in these cases of low

. The effective radiation temperature and size of the photosphere are determined by the stream velocity and

, and we find them to be a few times 104 K and 1014 cm in our calculations, comparable to the values inferred for some TDE candidates. The size of the photosphere is directly proportional to

, which can explain its rapidly changing size as seen in TDE candidates such as PS1-10jh.
THE CARINA PROJECT. X. ON THE KINEMATICS OF OLD AND INTERMEDIATE-AGE STELLAR POPULATIONS*

†
Authors: Fabrizio M. , Bono G. , Nonino M. , Łokas E. L. , Ferraro I. , Iannicola G. , Buonanno R. , Cassisi S. , Coppola G. , Dall’Ora M. , Gilmozzi R. , Marconi M. , Monelli M. , Romaniello M. , Stetson P. B. , Thévenin F. , Walker A. R. 
Published: October 2016

ABSTRACT
We present new radial velocity (RV) measurements of old (horizontal branch) and intermediate-age (red clump) stellar tracers in the Carina dwarf spheroidal. They are based on more than 2200 low-resolution spectra collected with VIMOS at Very Large Telescope (VLT). The targets are faint (20 ≲ V ≲ 21.5 mag), but the accuracy at the faintest limit is ≤9 km s−1. These data were complemented with RV measurements either based on spectra collected with FORS2 and FLAMES/GIRAFFE at VLT or available in the literature. We ended up with a sample of 2748 stars and among them, 1389 are candidate Carina stars. We found that the intermediate-age stellar component shows a well-defined rotational pattern around the minor axis. The western and the eastern side of the galaxy differ by +5 and −4 km s−1 when compared with the main RV peak. The old stellar component is characterized by a larger RV dispersion and does not show evidence of the RV pattern. We compared the observed RV distribution with N-body simulations for a former disky dwarf galaxy orbiting a giant Milky Way–like galaxy. We rotated the simulated galaxy by 60° with respect to the major axis, we kept the observer on the orbital plane of the dwarf and extracted a sample of stars similar to the observed one. Observed and predicted

ratios across the central regions are in remarkable agreement. This evidence indicates that Carina was a disky dwarf galaxy that experienced several strong tidal interactions with the Milky Way. Owing to these interactions, Carina transformed from a disky to a prolate spheroid and the rotational velocity transformed into random motions.
CARMA LARGE AREA STAR FORMATION SURVEY: DENSE GAS IN THE YOUNG L1451 REGION OF PERSEUS
Authors: Storm Shaye , Mundy Lee G. , Lee Katherine I. , Fernández-López Manuel , Looney Leslie W. , Teuben Peter , Arce Héctor G. , Rosolowsky Erik W. , Meisner Aaron M. , Isella Andrea , Kauffmann Jens , Shirley Yancy L. , Kwon Woojin , Plunkett Adele L. , Pound Marc W. , Segura-Cox Dominique M. , Tassis Konstantinos , Tobin John J. , Volgenau Nikolaus H. , Crutcher Richard M. , Testi Leonardo 
Published: October 2016

ABSTRACT
We present a 3 mm spectral line and continuum survey of L1451 in the Perseus Molecular Cloud. These observations are from the CARMA Large Area Star Formation Survey (CLASSy), which also imaged Barnard 1, NGC 1333, Serpens Main, and Serpens South. L1451 is the survey region with the lowest level of star formation activity—it contains no confirmed protostars. HCO+, HCN, and N2H+

(
J
=
1
→
0
)

are all detected throughout the region, with HCO+ being the most spatially widespread, and molecular emission seen toward 90% of the area above N(H2) column densities of 1.9 × 1021 cm−2. HCO+ has the broadest velocity dispersion, near 0.3 km s−1 on average, compared with ∼0.15 km s−1 for the other molecules, thus representing a range of subsonic to supersonic gas motions. Our non-binary dendrogram analysis reveals that the dense gas traced by each molecule has a similar hierarchical structure, and that gas surrounding the candidate first hydrostatic core (FHSC), L1451-mm, and other previously detected single-dish continuum clumps has similar hierarchical structure; this suggests that different subregions of L1451 are fragmenting on the pathway to forming young stars. We determined that the three-dimensional morphology of the largest detectable dense-gas structures was relatively ellipsoidal compared with other CLASSy regions, which appeared more flattened at the largest scales. A virial analysis shows that the most centrally condensed dust structures are likely unstable against collapse. Additionally, we identify a new spherical, centrally condensed N2H+ feature that could be a new FHSC candidate. The overall results suggest that L1451 is a young region starting to form its generation of stars within turbulent, hierarchical structures.
INSIGHTS INTO HYDROCARBON CHAIN AND AROMATIC RING FORMATION IN THE INTERSTELLAR MEDIUM: COMPUTATIONAL STUDY OF THE ISOMERS OF
AND
AND THEIR FORMATION PATHWAYS
Authors: Peverati Roberto , Bera Partha P. , Lee Timothy J. , Head-Gordon Martin 
Published: October 2016

ABSTRACT
Small hydrocarbons such as acetylene is present in circumstellar envelopes of carbon-rich stars, but the processes that yield larger molecules, and eventually polycyclic aromatic hydrocarbons (PAHs), remain poorly understood. To gain additional insight into the early steps of such processes, electronic structure calculations were performed on the potential energy surfaces of

,

and

. The results establish reactive pathways from acetylene and its ion to formation of the first aromatic ring. We characterize the stable isomers, their spectroscopic properties, and many of the transition structures that represent barriers to isomerization. The pathways to stabilized

and

are most likely to arise from unimolecular decomposition of hot

and

by H atom elimination. By contrast, we found an ion-molecule pathway to

to be very stable to fragmentation and elimination reactions even without collisional stabilization. This aromatic species is a good nucleation center for the growth of larger PAHs in interstellar conditions.
EXTENDED RELATIVISTIC CONFIGURATION INTERACTION AND MANY-BODY PERTURBATION CALCULATIONS OF SPECTROSCOPIC DATA FOR THE N ≤ 6 CONFIGURATIONS IN Ne-LIKE IONS BETWEEN Cr xv AND Kr xxvii
Authors: Wang K. , Chen Z. B. , Si R. , Jönsson P. , Ekman J. , Guo X. L. , Li S. , Long F. Y. , Dang W. , Zhao X. H. , Hutton R. , Chen C. Y. , Yan J. , Yang X. 
Published: October 2016

ABSTRACT
Level energies, wavelengths, electric dipole, magnetic dipole, electric quadrupole, and magnetic quadrupole transition rates, oscillator strengths, and line strengths from combined relativistic configuration interaction and many-body perturbation calculations are reported for the 201 fine-structure states of the

,

,

,

,

,

, and

configurations in all Ne-like ions between Cr xv and Kr xxvii. Calculated level energies and transition data are compared with experiments from the National Institute of Standards and Technology (NIST) and CHIANTI databases, and other recent benchmark calculations. The mean energy difference with the NIST experiments is only 0.05%. The present calculations significantly increase the amount of accurate spectroscopic data for the n > 3 states in a number of Ne-like ions of astrophysical interest. A complete data set should be helpful for analyzing new observations from solar and other astrophysical sources, and is also likely to be useful for modeling and diagnosing a variety of plasmas, including astronomical and fusion plasma.
A CATALOG OF ECLIPSING BINARIES AND VARIABLE STARS OBSERVED WITH ASTEP 400 FROM DOME C, ANTARCTICA
Authors: Chapellier E. , Mékarnia D. , Abe L. , Guillot T. , Agabi K. , Rivet J.-P. , Schmider F.-X. , Crouzet N. , Aristidi E. 
Published: October 2016

ABSTRACT
We used the large photometric database of the ASTEP program, whose primary goal was to detect exoplanets in the southern hemisphere from Antarctica, to search for eclipsing binaries (EcBs) and variable stars. 673 EcBs and 1166 variable stars were detected, including 31 previously known stars. The resulting online catalogs give the identification, the classification, the period, and the depth or semi-amplitude of each star. Data and light curves for each object are available at http://astep-vo.oca.eu.
L’approche du décrochage scolaire selon les théories culturalistes de l’activité. Bénéfices et perspectives
Authors: Flavier Éric , Méard Jacques 
Published: October 2016

Actuellement, les politiques éducatives portent une attention accrue à la prévention et la lutte contre le décrochage scolaire, notamment parce qu’il représente un indicateur de l’état de santé des systèmes éducatifs. Les nombreuses études sur le sujet, principalement sociologiques, permettent de comprendre le phénomène comme un processus complexe et multifactoriel de désadhésion au travail scolaire. Dans leur prolongement, cet article, sur fond d’études empiriques, se donne pour ambition d’appréhender la problématique de la lutte contre le décrochage scolaire à partir d’une approche dite « orientée activité », c’est-à-dire au plus près des acteurs, de leurs pratiques et des significations qu’ils leur accordent en contexte de travail. Nous déclinerons trois hypothèses spécifiques de ce courant : l’hypothèse d’un développement par le sens et l’efficience, l’hypothèse d’un développement par des motifs concurrents, l’hypothèse d’un développement dans un « système d’activité ». L’adoption de ces hypothèses offre de nouvelles perspectives d’étude du phénomène dans une visée développementale, soutenant ainsi l’accroissement du pouvoir d’agir des professionnels de l’éducation au profit d’un meilleur accrochage scolaire des élèves et professionnel des enseignants.
L’activité de travail du professeur de fitness au prisme de la solidarité technique
Authors: Pichot Lilian 
Published: October 2016

Consacré à la vie de travail dans les petites entreprises de fitness, cet article dévoile une activité de travail qui dépasse les planifications usuelles. L’activité de travail dans les clubs de fitness donne à voir des scènes de travail que les concepts de travail d’organisation et de solidarité technique nous permettent de mieux saisir. L’agir au travail, inextricablement individuel et collectif, se forge dans une chaine d’interdépendances situées ici et là qui rassemblent exploitants, professeurs de fitness et usagers consommateurs. Ces interdépendances redéfinissent le travail d’organisation et l’accomplissement de soi au travail. Marqué par la promiscuité, le travail du prof de fitness s’appuie sur des ressources techniques, corporelles, cognitives et relationnelles qui tentent d’apprivoiser une somme d’incertitudes parmi lesquelles les intentions d’agir parfois dissimulées des destinataires du service. Ce faisant, l’activité professionnelle révèle une émancipation individuelle, affranchie des standards comportementaux indigènes. Elle est assujettie aux formes collectives plurielles du travail « en train de se faire », qui passe, outre la possession de capacités physico-techniques et corporelles, par l’appropriation de rôles adaptés à l’arène et taillés selon la réputation acquise.
(In)Visibilité de l’art sur les réseaux sociaux numériques (RSN) : analyser l’acceptation des RSN par les artistes
Authors: Porcher Amandine , Vacherand-Revel Jacqueline , Bobillier Chaumon Marc-Éric , Moktari Manon , Cuvillier Bruno 
Published: October 2016

Les Réseaux Sociaux Numériques représentent a priori des instruments médiateurs de l’activité, essentielle, de « mise en visibilité » des artistes. Mais l’usage de ces dispositifs peut aussi être une contrainte ou un empêchement. Aussi, cette étude poursuit le but d’identifier les facteurs favorables et défavorables à l’acceptation des RSN par les artistes. Le cadre théorique de « l’acceptation située » des technologies selon Bobillier Chaumon (2013) est mobilisé pour soutenir une démarche de recherche qualitative auprès de 15 artistes numériques et traditionnels. L’analyse thématique de 12 entretiens semi-directifs et 4 entretiens à visée d’explicitation révèle que le processus « d’acceptation » des technologies s’inscrit dans un rapport aux technologies déjà existant qui dépend des expériences vécues avec des dispositifs technologiques et de la façon dont la technologie s’ancre dans la démarche artistique. Ce processus est modulé par des leviers principalement rattachés aux dimensions « personnelle et interpersonnelle » du modèle « d’acceptation située », et des freins se rapportent principalement aux dimensions « personnelle, transpersonnelle et métapersonnelle ». Nous avons identifié quatre types de stratégies de régulation déployées pour faire face aux freins. Les stratégies qualifiées de « narratives » représenteraient un intérêt spécifique pour l’acceptation du RSN et pour la profession d’artiste en sollicitant créativité et esthétique.
Les forums virtuels : ressource pour le développement des pratiques et du bien-être des professionnels
Authors: Prost Magali , Cahour Béatrice , Détienne Françoise 
Published: October 2016

L’étude se situe dans la perspective de l’ergonomie constructive (Falzon, 2013) et cherche à savoir si le forum d’enseignants du primaire étudié est une ressource qui permet le développement du pouvoir d’agir des participants, et à quelles conditions ceux-ci s’engagent sur le forum (facteurs de conversion - Fernagu-Oudet, 2012 ; Sen, 2001). Le pouvoir d’agir est envisagé sous l’angle du développement des pratiques (dimension constructive) et du développement du bien-être (dimension émotionnelle). Trois méthodes complémentaires de recueil de données ont été mises en place : (1) un questionnaire diffusé sur le forum EDP (quatre-vingts participants), (2) neuf entretiens d’auto-confrontation basés sur les traces écrites des discussions, et (3) vingt fils de discussions sélectionnés sur le forum. Une analyse de contenu a été réalisée sur l’ensemble des données à partir des catégories proposées par Mollo et Nascimento (2013) concernant les effets bénéfiques de l’activité réflexive, ainsi que des catégories liées à la dimension émotionnelle (témoignage de soutien émotionnel et amélioration de l’expérience émotionnelle). Les résultats mettent en évidence l’apport développemental des échanges au niveau de l’élaboration collective d’outils pédagogiques, de règles de métier, de savoirs et de savoir-faire. Le versant émotionnel est présent dans tous les échanges. Deux facteurs de conversion ont été identifiés : l’anonymat de l’identité réelle et la présence d’une communauté de pairs bienveillante, réactive et partageant les mêmes pratiques. Les résultats sont discutés au regard du développement de la pratique et du bien-être des professionnels, ainsi que des conditions nécessaires pour qu’un tel développement puisse avoir lieu au sein même des établissements.
Une structure dialogique et plastique : une hypothèse de l’usage de Néopass@ction
Authors: Espinassy Laurence 
Published: October 2016

Nous interrogeons la forme et l’usage d’un artefact de formation destiné au métier enseignant proposant une « entrée activité » : la plateforme de ressources en ligne Néopass@ction, et plus particulièrement le thème « Aider les élèves à travailler et à apprendre » (Accès en ligne : http://neo.ens-lyon.fr/neo) que nous avons conçu (Félix & Espinassy, 2011). Nous soutenons l’hypothèse que les choix de conception, notamment une entrée par les « dilemmes professionnels », ainsi que l’organisation formelle de ces ressources correspondant à des formes historico-culturelles préexistantes (artistiques, plastiques, littéraires…), favorisent une mise en débat de situations de travail comme moyen d’entrer progressivement dans le métier. Nous interrogeons la structure dialogique de cet artefact et les « hypothèses instrumentales » des opérateurs et des concepteurs.