bluuebunny/crossref_metadata_2025_split huggingface dataset:
TURBULENT CHEMICAL DIFFUSION IN CONVECTIVELY BOUNDED CARBON FLAMES
Authors: Lecoanet Daniel , Schwab Josiah , Quataert Eliot , Bildsten Lars , Timmes F. X. , Burns Keaton J. , Vasil Geoffrey M. , Oishi Jeffrey S. , Brown Benjamin P. 
Published: November 2016

ABSTRACT
It has been proposed that mixing induced by convective overshoot can disrupt the inward propagation of carbon deflagrations in super-asymptotic giant branch stars. To test this theory, we study an idealized model of convectively bounded carbon flames with 3D hydrodynamic simulations of the Boussinesq equations using the pseudo-spectral code Dedalus. Because the flame propagation timescale is much longer than the convection timescale, we approximate the flame as fixed in space, and only consider its effects on the buoyancy of the fluid. By evolving a passive scalar field, we derive a turbulent chemical diffusivity produced by the convection as a function of height,

. Convection can stall a flame if the chemical mixing timescale, set by the turbulent chemical diffusivity,

, is shorter than the flame propagation timescale, set by the thermal diffusivity, κ, i.e., when

. However, we find

for most of the flame because convective plumes are not dense enough to penetrate into the flame. Extrapolating to realistic stellar conditions, this implies that convective mixing cannot stall a carbon flame and that “hybrid carbon–oxygen–neon” white dwarfs are not a typical product of stellar evolution.
MAGNETAR-POWERED SUPERNOVAE IN TWO DIMENSIONS. I. SUPERLUMINOUS SUPERNOVAE
Authors: Chen Ke-Jung , Woosley S. E. , Sukhbold Tuguldur 
Published: November 2016

ABSTRACT
Previous studies have shown that the radiation emitted by a rapidly rotating magnetar embedded in a young supernova can greatly amplify its luminosity. These one-dimensional studies have also revealed the existence of an instability arising from the piling up of radiatively accelerated matter in a thin dense shell deep inside the supernova. Here, we examine the problem in two dimensions and find that, while instabilities cause mixing and fracture this shell into filamentary structures that reduce the density contrast, the concentration of matter in a hollow shell persists. The extent of the mixing depends upon the relative energy input by the magnetar and the kinetic energy of the inner ejecta. The light curve and spectrum of the resulting supernova will be appreciably altered, as will the appearance of the supernova remnant, which will be shellular and filamentary. A similar pile up and mixing might characterize other events where energy is input over an extended period by a centrally concentrated source, e.g., a pulsar, radioactive decay, a neutrino-powered wind, or colliding shells. The relevance of our models to the recent luminous transient ASASSN-15lh is briefly discussed.
FAR-UV EMISSION PROPERTIES OF FR1 RADIO GALAXIES
Authors: Danforth Charles W. , Stocke John T. , France Kevin , Begelman Mitchell C. , Perlman Eric 
Published: November 2016

ABSTRACT
The power mechanism and accretion geometry for low-power FR 1 radio galaxies are poorly understood in comparison to those for Seyfert galaxies and QSOs. In this paper, we use the diagnostic power of the Lyα recombination line observed using the Cosmic Origins Spectrograph (COS) aboard the Hubble Space Telescope (HST) to investigate the accretion flows in three well-known, nearby FR 1s: M87, NGC 4696, and Hydra A. The Lyα emission line’s luminosity, velocity structure, and the limited knowledge of its spatial extent provided by COS are used to assess conditions within a few parsecs of the supermassive black hole in these radio-mode active galactic nuclei. We observe strong Lyα emission in all three objects with total luminosity similar to that seen in BL Lacertae objects. M87 shows a complicated emission-line profile in Lyα, which varies spatially across the COS aperture and possibly temporally over several epochs of observation. In both NGC 4696 and M87, the Lyα luminosities ∼1040 erg s−1 are closely consistent with the observed strength of the ionizing continuum in Case B recombination theory and with the assumption of a near-unity covering factor. It is possible that the Lyα-emitting clouds are ionized largely by beamed radiation associated with the jets. Long-slit UV spectroscopy can be used to test this hypothesis. Hydra A and the several BL Lac objects studied in this and previous papers have Lyα luminosities larger than M87 but their extrapolated, nonthermal continua are so luminous that they overpredict the observed strength of Lyα, a clear indicator of relativistic beaming in our direction. Given their substantial space density (∼4 × 10−3 Mpc−3), the unbeamed Lyman continuum radiation of FR 1s may make a substantial minority contribution (∼10%) to the local UV background if all FR 1s are similar to M87 in ionizing flux level.
THE EVOLUTION OF STAR FORMATION HISTORIES OF QUIESCENT GALAXIES
Authors: Pacifici Camilla , Kassin Susan A. , Weiner Benjamin J. , Holden Bradford , Gardner Jonathan P. , Faber Sandra M. , Ferguson Henry C. , Koo David C. , Primack Joel R. , Bell Eric F. , Dekel Avishai , Gawiser Eric , Giavalisco Mauro , Rafelski Marc , Simons Raymond C. , Barro Guillermo , Croton Darren J. , Davé Romeel , Fontana Adriano , Grogin Norman A. , Koekemoer Anton M. , Lee Seong-Kook , Salmon Brett , Somerville Rachel , Behroozi Peter 
Published: November 2016

ABSTRACT
Although there has been much progress in understanding how galaxies evolve, we still do not understand how and when they stop forming stars and become quiescent. We address this by applying our galaxy spectral energy distribution models, which incorporate physically motivated star formation histories (SFHs) from cosmological simulations, to a sample of quiescent galaxies at

. A total of 845 quiescent galaxies with multi-band photometry spanning rest-frame ultraviolet through near-infrared wavelengths are selected from the Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey (CANDELS) data set. We compute median SFHs of these galaxies in bins of stellar mass and redshift. At all redshifts and stellar masses, the median SFHs rise, reach a peak, and then decline to reach quiescence. At high redshift, we find that the rise and decline are fast, as expected, because the universe is young. At low redshift, the duration of these phases depends strongly on stellar mass. Low-mass galaxies (

) grow on average slowly, take a long time to reach their peak of star formation (

Gyr), and then the declining phase is fast (

Gyr). Conversely, high-mass galaxies (

) grow on average fast (

Gyr), and, after reaching their peak, decrease the star formation slowly (

). These findings are consistent with galaxy stellar mass being a driving factor in determining how evolved galaxies are, with high-mass galaxies being the most evolved at any time (i.e., downsizing). The different durations we observe in the declining phases also suggest that low- and high-mass galaxies experience different quenching mechanisms, which operate on different timescales.
THE SYSTEMATICS OF STRONG LENS MODELING QUANTIFIED: THE EFFECTS OF CONSTRAINT SELECTION AND REDSHIFT INFORMATION ON MAGNIFICATION, MASS, AND MULTIPLE IMAGE PREDICTABILITY
Authors: Johnson Traci L. , Sharon Keren 
Published: November 2016

ABSTRACT
Until now, systematic errors in strong gravitational lens modeling have been acknowledged but have never been fully quantified. Here, we launch an investigation into the systematics induced by constraint selection. We model the simulated cluster Ares 362 times using random selections of image systems with and without spectroscopic redshifts and quantify the systematics using several diagnostics: image predictability, accuracy of model-predicted redshifts, enclosed mass, and magnification. We find that for models with >15 image systems, the image plane rms does not decrease significantly when more systems are added; however, the rms values quoted in the literature may be misleading as to the ability of a model to predict new multiple images. The mass is well constrained near the Einstein radius in all cases, and systematic error drops to <2% for models using >10 image systems. Magnification errors are smallest along the straight portions of the critical curve, and the value of the magnification is systematically lower near curved portions. For >15 systems, the systematic error on magnification is ∼2%. We report no trend in magnification error with the fraction of spectroscopic image systems when selecting constraints at random; however, when using the same selection of constraints, increasing this fraction up to ∼0.5 will increase model accuracy. The results suggest that the selection of constraints, rather than quantity alone, determines the accuracy of the magnification. We note that spectroscopic follow-up of at least a few image systems is crucial because models without any spectroscopic redshifts are inaccurate across all of our diagnostics.
PHASE QUANTIZATION STUDY OF SPATIAL LIGHT MODULATOR FOR EXTREME HIGH-CONTRAST IMAGING
Authors: Dou Jiangpei , Ren Deqing 
Published: November 2016

ABSTRACT
Direct imaging of exoplanets by reflected starlight is extremely challenging due to the large luminosity ratio to the primary star. Wave-front control is a critical technique to attenuate the speckle noise in order to achieve an extremely high contrast. We present a phase quantization study of a spatial light modulator (SLM) for wave-front control to meet the contrast requirement of detection of a terrestrial planet in the habitable zone of a solar-type star. We perform the numerical simulation by employing the SLM with different phase accuracy and actuator numbers, which are related to the achievable contrast. We use an optimization algorithm to solve the quantization problems that is matched to the controllable phase step of the SLM. Two optical configurations are discussed with the SLM located before and after the coronagraph focal plane mask. The simulation result has constrained the specification for SLM phase accuracy in the above two optical configurations, which gives us a phase accuracy of 0.4/1000 and 1/1000 waves to achieve a contrast of 10−10. Finally, we have demonstrated that an SLM with more actuators can deliver a competitive contrast performance on the order of 10−10 in comparison to that by using a deformable mirror.
THE LOST DWARFS OF CENTAURUS A AND THE FORMATION OF ITS DARK GLOBULAR CLUSTERS
Authors: Bovill Mia Sauda , Puzia Thomas H. , Ricotti Massimo , Taylor Matthew A. 
Published: November 2016

ABSTRACT
We present theoretical constraints for the formation of the newly discovered dark star clusters (DSCs) with high mass-to-light (

) ratios, from Taylor et al. These compact stellar systems photometrically resemble globular clusters (GCs) but have dynamical

ratios of ∼10–100, closer to the expectations for dwarf galaxies. The baryonic properties of the DSCs suggest that their host dark matter halos likely virialized at high redshift with

. We use a new set of high-resolution N-body simulations of Centaurus A to determine whether there is a set of z = 0 subhalos whose properties are in line with these observations. While we find such a set of subhalos, when we extrapolate the dark matter density profiles into the inner 20 pc, no dark matter halo associated with Centaurus A in our simulations, at any redshift, can replicate the extremely high central mass densities of the DSCs. Among the most likely options for explaining 105–

within subhalos of 10 pc diameter is the presence of a central massive black hole (BH). We therefore propose that the DSCs are remnant cusps of stellar systems surrounding the central BHs of dwarf galaxies that have been almost completely destroyed by interactions with Centaurus A.
MERGING GALAXIES WITH TIDAL TAILS IN COSMOS TO z = 1
Authors: Wen (闻璋正) Zhang Zheng , Zheng (郑宪忠) Xian Zhong 
Published: November 2016

ABSTRACT
Tidal tails are created in major mergers involving disk galaxies. It remains to be explored how the tidal tails trace the assembly history of massive galaxies. We identify a sample of 461 merging galaxies with long tidal tails, from 35,076 galaxies mass-complete at

and

, based on Hubble Space Telescope/ACS F814W imaging data and public catalogs of the COSMOS field. The long tails refer to those with length equal to or greater than the diameter of their host galaxies. The mergers with tidal tails are selected using our novel

technique for strong asymmetric features, along with visual examination. Our results show that the fraction of tidal-tailed mergers evolves mildly with redshift, as

, and becomes relatively higher in less-massive galaxies, out to z = 1. With a timescale of 0.5 Gyr for the tidal-tailed mergers, we obtain that the occurrence rate of such mergers follows

Gyr−1, and corresponds to ∼0.3 events since z = 1, as well as roughly one-third of the total budget of major mergers from the literature. For disk-involved major mergers, nearly half of them have undergone a phase with long tidal tails.
GRAVITY-DARKENED SEASONS: INSOLATION AROUND RAPID ROTATORS
Authors: Ahlers John P. 
Published: November 2016

ABSTRACT
I model the effect of rapid stellar rotation on a planet’s insolation. Fast-rotating stars have induced pole-to-equator temperature gradients (known as gravity darkening) of up to several thousand Kelvin that affect the star’s luminosity and peak emission wavelength as a function of latitude. When orbiting such a star, a planet’s annual insolation can strongly vary depending on its orbital inclination. Specifically, inclined orbits result in temporary exposure to the star’s hotter poles. I find that gravity darkening can drive changes in a planet’s equilibrium temperature of up to ∼15% due to increased irradiance near the stellar poles. This effect can also vary a planet’s exposure to UV radiation by up to ∼80% throughout its orbit as it is exposed to an irradiance spectrum corresponding to different stellar effective temperatures over time.
Rapport de synthèse
Authors: Derieux Emmanuel 
Published: November 2016

« Informer n’est pas un délit », mais quelques méthodes d’enquête utilisées et divers contenus diffusés peuvent l’être, en raison de la nécessaire protection de droits individuels ou collectifs concurrents. Il convient de déterminer de justes limites aux abus de la liberté d’expression et, dans un souci d’équilibre des droits et le respect de certaines formes, d’en assurer l’application.
La victoire à trois points dans le football a-t-elle rendu les équipes plus offensives ?
Authors: Duhautois Richard , Eyssautier Romain 
Published: November 2016

Dans les années 1990, la règle de la victoire à trois points a été introduite par les fédérations de football. Le système 2 points pour une victoire, 1 point pour le match nul et 0 point pour une défaite a été remplacé par 3 points pour une victoire, 1 point pour un match nul et 0 point pour une défaite. Le but de cette réforme était d’augmenter la récompense obtenue lors d’une victoire afin d’influencer les tactiques des équipes et de les rendre plus offensives. Nous comparons la part des matchs nuls avant et après la réforme dans le Championnat de France de première division et la Coupe de France. En utilisant une méthode d’estimation en doubles différences, nous montrons que la répartition des victoires est affectée par le changement de règle : la part des victoires à l’extérieur a augmenté et la part des victoires à domicile a diminué, laissant inchangée la part des matchs nuls.
Brutality or Frequency?
Authors: Arin K. Peren , Spagnolo Fabio , Spagnolo Nicola 
Published: November 2016

Ce travail examine les effets du terrorisme sur la croissance économique en Inde. En utilisant un modèle de Markov à changement de régime, on trouve des preuves que le terrorisme a des effets importants et négatifs sur la croissance économique de l’Inde. Nos résultats empiriques montrent aussi que l’ampleur de ces effets est plus grande dans des périodes de haute croissance économique. Enfin, nous comparons l’ampleur des effets de « brutalité » et de « fréquence » des attaques terroristes et nous concluons que l’effet de « fréquence » est légèrement plus élevé que l’effet de « brutalité ».	JEL Classification: C32, E2.
La balance du carbone incorporé au commerce bilatéral entre la France et la Chine : transferts d’émissions ou nouvelles créations ?
Authors: He Jie , Jacquemin Johan 
Published: November 2016

Nous calculons la balance des émissions de carbone incorporées au commerce (BEIC) bilatéral franco-chinois entre 1996 et 2005. Les résultats confirment le rôle d’exportateur net en carbone de la Chine et l’augmentation rapide de l’excédent de la BEIC depuis l’adhésion de la Chine à l’Organisation mondiale du commerce. Cependant, la quasi-totalité de cet excédent est due à la faible efficacité en carbone de la Chine par rapport à la France. La part de carbone émis sur le sol chinois réellement transféré de la France vers la Chine reste très faible (1-2 %). Le commerce franco-chinois semble continuer à profiter essentiellement de leurs différences de dotations factorielles. L’avantage comparatif issu des réglementations environnementales ne joue qu’un rôle marginal.
Comparison of 360-Degree Circumferential Trabeculotomy and Conventional Trabeculotomy in Primary Pediatric Glaucoma Surgery: Part 1
Authors: Celea Christiana , Dragosloveanu Serban , Pop Mihai , Celea Cristian 
Published: November 2016

Purpose:
To quantify the outcomes of a single circumferential trabeculotomy versus a single conventional trabeculotomy after 2 years of follow-up in patients who underwent primary pediatric glaucoma surgery.

Methods:
This was a retrospective study of patients aged 1 day to 3 years who underwent primary pediatric glaucoma surgery. A total of 45 patients (79 eyes) were followed up for 2 years. There were two groups: the 360-degrees circumferential trabeculotomy with illuminated catheter group and the conventional trabeculotomy group.

Results:
Mean age was 5.37 ± 6.32 months. There were 41 eyes with circumferential trabeculotomy and 38 eyes with conventional trabeculotomy. In the circumferential group, the technique could not be completed in 3 eyes (7.31%) because of severe canal malformations. Mean intraocular pressure and corneal diameter decreased in both groups postoperatively. At 2 years' follow-up, intraocular pressure (IOP) decreased, with 13.61 mm Hg in the circumferential group and 9.09 mm Hg in the conventional group. At 6 months postoperatively, corneal diameter decreased, with 0.52 mm in the circumferential group and 0.27 mm in the conventional group. Axial length remained the same.

Conclusions:
Both procedures were successful, but circumferential trabeculotomy was better than the conventional procedure for lowering IOP, with an average of 4.52 mm Hg at 2 years' follow-up. The decrease in postoperative corneal diameter was also better in the circumferential group. The mean preoperative and postoperative axial lengths were similar in both groups; thus, the surgery did not influence this measurement in the studied cases.

[
J Pediatr Ophthalmol Strabismus.
2016;53(6):357–364.]
Quelques implications pédagogiques de l’apprentissage de l’arabe comme langue pluriglossique et langue de spécialité dans un enseignement militaire de type Lansad
Authors: Baize-Varin Marie 
Published: November 2016

Cet article traite de la spécificité de l’enseignement de l’arabe aux Écoles de Saint-Cyr Coëtquidan (ESCC), école de formation initiale des officiers de l’armée de Terre française. Il montre en quoi l’enseignement de l’arabe y est particulièrement révélateur de la pluriglossie de cette langue, puisque dépendant ici des besoins des apprenants. En effet, l’arabe, en tant que langue de spécialité militaire – si nous abordons d’un point de vue lexical le concept de langue de spécialité - est étudié par deux publics différents. Cependant, étant donné que les élèves-officiers des ESCC sont considérés comme « spécialistes d’autres disciplines » et que la formation qui y est délivrée est dite « intégrée » (militaire, académique et comportementale), nous pouvons voir ici une convergence entre Lansad et langue de spécialité. Encore faut-il déterminer de quel(s) arabe(s)il s’agit.
The Use of 2 Conditioning Programs and the Fitness Characteristics of Police Academy Cadets
Authors: Cocke Charles , Dawes Jay , Orr Robin Marc 
Published: November 2016

Context: Police academy training must physically prepare cadets for the rigors of their occupational tasks to prevent injury and allow them to adequately perform their duties.
Objective: To compare the effects of 2 physical training programs on multiple fitness measures in police cadets.
Design: Cohort study.
Setting: Police training academy.
Patients or Other Participants: We collected data from 70 male (age = 27.4 ± 5.9 years, body weight = 85.4 ± 11.8 kg) and 20 female (age = 30.5 ± 5.8 years, body weight = 62.8 ± 11.0 kg) police cadets and analyzed data from 61 male cadets (age = 27.5 ± 5.5 years, body weight = 87.7 ± 13.2 kg).
Intervention(s): Participants completed one of two 6-month training programs. The randomized training group (RTG; n = 50), comprising 4 separate and sequential groups (n = 13, n = 11, n = 13, n = 13), completed a randomized training program that incorporated various strength and endurance exercises chosen on the day of training. The periodized group (PG; n = 11) completed a periodized training program that alternated specific phases of training.
Main Outcome Measure(s): Anthropometric fitness measures were body weight, fat mass, and lean body mass. Muscular and metabolic fitness measures were 1-repetition maximum bench press, push-up and sit-up repetitions performed in 1 minute, vertical jump, 300-m sprint, and 2.4-km run.
Results: The RTG demonstrated improvements in all outcome measures between pretraining and posttraining; however, the improvements varied among the 4 individual RTGs. Conversely, the PG displayed improvements in only 3 outcome measures (push-ups, sit-ups, and 300-m sprint) but approached the level of significance set for this study (P &lt; .01) in body weight, fat mass, and 1-repetition maximum bench press.
Conclusions: Regardless of format, physical training programs can improve the fitness of tactical athletes. In general, physical fitness measures appeared to improve more in the RTG than in the PG. However, this observation varied among groups, and injury rates were not compared.