bluuebunny/crossref_metadata_2025_split huggingface dataset:
TURBULENCE, TRANSPORT, AND WAVES IN OHMIC DEAD ZONES
Authors: Gole Daniel , Simon Jacob B. , Lubow Stephen H. , Armitage Philip J. 
Published: July 2016

ABSTRACT
We use local numerical simulations to study a vertically stratified accretion disk with a resistive mid-plane that damps magnetohydrodynamic (MHD) turbulence. This is an idealized model for the dead zones that may be present at some radii in protoplanetary and dwarf novae disks. We vary the relative thickness of the dead and active zones to quantify how forced fluid motions in the dead zone change. We find that the residual Reynolds stress near the mid-plane decreases with increasing dead zone thickness, becoming negligible in cases where the active to dead mass ratio is less than a few percent. This implies that purely Ohmic dead zones would be vulnerable to episodic accretion outbursts via the mechanism of Martin & Lubow. We show that even thick dead zones support a large amount of kinetic energy, but this energy is largely in fluid motions that are inefficient at angular momentum transport. Confirming results from Oishi & Mac Low, the perturbed velocity field in the dead zone is dominated by an oscillatory, vertically extended circulation pattern with a low frequency compared to the orbital frequency. This disturbance has the properties predicted for the lowest order r mode in a hydrodynamic disk. We suggest that in a global disk similar excitations would lead to propagating waves, whose properties would vary with the thickness of the dead zone and the nature of the perturbations (isothermal or adiabatic). Flows with similar amplitudes would buckle settled particle layers and could reduce the efficiency of pebble accretion.
CIRCUMSTELLAR DEBRIS DISKS: DIAGNOSING THE UNSEEN PERTURBER
Authors: Nesvold Erika R. , Naoz Smadar , Vican Laura , Farr Will M. 
Published: July 2016

ABSTRACT
The first indication of the presence of a circumstellar debris disk is usually the detection of excess infrared emission from the population of small dust grains orbiting the star. This dust is short-lived, requiring continual replenishment, and indicating that the disk must be excited by an unseen perturber. Previous theoretical studies have demonstrated that an eccentric planet orbiting interior to the disk will stir the larger bodies in the belt and produce dust via interparticle collisions. However, motivated by recent observations, we explore another possible mechanism for heating a debris disk: a stellar-mass perturber orbiting exterior to and inclined to the disk and exciting the disk particles’ eccentricities and inclinations via the Kozai–Lidov mechanism. We explore the consequences of an exterior perturber on the evolution of a debris disk using secular analysis and collisional N-body simulations. We demonstrate that a Kozai–Lidov excited disk can generate a dust disk via collisions and we compare the results of the Kozai–Lidov excited disk with a simulated disk perturbed by an interior eccentric planet. Finally, we propose two observational tests of a dust disk that can distinguish whether the dust was produced by an exterior brown dwarf or stellar companion or an interior eccentric planet.
EXPANDING MOLECULAR BUBBLE SURROUNDING TYCHO’S SUPERNOVA REMNANT (SN 1572) OBSERVED WITH THE IRAM 30 m TELESCOPE: EVIDENCE FOR A SINGLE-DEGENERATE PROGENITOR
Authors: Zhou (周平) Ping , Chen (陳陽) Yang , Zhang (張智昱) Zhi-Yu , Li (李向東) Xiang-Dong , Safi-Harb Samar , Zhou (周鑫) Xin , Zhang (張瀟) Xiao 
Published: July 2016

ABSTRACT
Whether the progenitors of SNe Ia are single-degenerate or double-degenerate white dwarf (WD) systems is a highly debated topic. To address the origin of Tycho’s Type Ia supernova remnant (SNR), SN 1572, we have carried out a 12CO J = 2–1 mapping and a 3 mm line survey toward the remnant using the IRAM 30 m telescope. We show that Tycho is surrounded by a clumpy molecular bubble at a local standard of rest velocity of

, which expands at a speed of

and has a mass of

(at the distance of 2.5 kpc). Enhanced 12CO J = 2–1 line emission relative to 12CO J = 1–0 emission and possible line broadenings (in velocity range −64 to −60 km s−1) are found at the northeastern boundary of the SNR, where the shell is deformed and decelerated. These features, combined with the morphological correspondence between the expanding molecular bubble and Tycho, suggest that the SNR is associated with the bubble at the velocity range −66 to −57 km s−1. The most plausible origin for the expanding bubble is the fast outflow (with velocity of hundreds km s−1) driven from the vicinity of a WD as it accreted matter from a nondegenerate companion star. The SNR has been expanding in the low-density wind-blown bubble, and the shock wave has just reached the molecular cavity wall. This is the first unambiguous detection of an expanding bubble driven by the progenitor of a Type Ia SNR, which constitutes evidence for a single-degenerate progenitor for this SN Ia.
SN 2015bn: A DETAILED MULTI-WAVELENGTH VIEW OF A NEARBY SUPERLUMINOUS SUPERNOVA
Authors: Nicholl M. , Berger E. , Smartt S. J. , Margutti R. , Kamble A. , Alexander K. D. , Chen T.-W. , Inserra C. , Arcavi I. , Blanchard P. K. , Cartier R. , Chambers K. C. , Childress M. J. , Chornock R. , Cowperthwaite P. S. , Drout M. , Flewelling H. A. , Fraser M. , Gal-Yam A. , Galbany L. , Harmanen J. , Holoien T. W.-S. , Hosseinzadeh G. , Howell D. A. , Huber M. E. , Jerkstrand A. , Kankare E. , Kochanek C. S. , Lin Z.-Y. , Lunnan R. , Magnier E. A. , Maguire K. , McCully C. , McDonald M. , Metzger B. D. , Milisavljevic D. , Mitra A. , Reynolds T. , Saario J. , Shappee B. J. , Smith K. W. , Valenti S. , Villar V. A. , Waters C. , Young D. R. 
Published: July 2016

ABSTRACT
We present observations of SN 2015bn (=PS15ae = CSS141223-113342+004332 = MLS150211-113342+004333), a Type I superluminous supernova (SLSN) at redshift z = 0.1136. As well as being one of the closest SLSNe I yet discovered, it is intrinsically brighter (

) and in a fainter galaxy (

) than other SLSNe at

. We used this opportunity to collect the most extensive data set for any SLSN I to date, including densely sampled spectroscopy and photometry, from the UV to the NIR, spanning −50 to +250 days from optical maximum. SN 2015bn fades slowly, but exhibits surprising undulations in the light curve on a timescale of 30–50 days, especially in the UV. The spectrum shows extraordinarily slow evolution except for a rapid transformation between +7 and +20–30 days. No narrow emission lines from slow-moving material are observed at any phase. We derive physical properties including the bolometric luminosity, and find slow velocity evolution and non-monotonic temperature and radial evolution. A deep radio limit rules out a healthy off-axis gamma-ray burst, and places constraints on the pre-explosion mass loss. The data can be consistently explained by a

M

stripped progenitor exploding with

erg kinetic energy, forming a magnetar with a spin-down timescale of ∼20 days (thus avoiding a gamma-ray burst) that reheats the ejecta and drives ionization fronts. The most likely alternative scenario—interaction with ∼20 M

of dense, inhomogeneous circumstellar material—can be tested with continuing radio follow-up.
TESTING THE PROPAGATING FLUCTUATIONS MODEL WITH A LONG, GLOBAL ACCRETION DISK SIMULATION
Authors: Hogg J Drew , Reynolds Christopher S. 
Published: July 2016

ABSTRACT
The broadband variability of many accreting systems displays characteristic structures; log-normal flux distributions, root-mean square (rms)-flux relations, and long inter-band lags. These characteristics are usually interpreted as inward propagating fluctuations of the mass accretion rate in an accretion disk driven by stochasticity of the angular momentum transport mechanism. We present the first analysis of propagating fluctuations in a long-duration, high-resolution, global three-dimensional magnetohydrodynamic (MHD) simulation of a geometrically thin (h/r ≈ 0.1) accretion disk around a black hole. While the dynamical-timescale turbulent fluctuations in the Maxwell stresses are too rapid to drive radially coherent fluctuations in the accretion rate, we find that the low-frequency quasi-periodic dynamo action introduces low-frequency fluctuations in the Maxwell stresses, which then drive the propagating fluctuations. Examining both the mass accretion rate and emission proxies, we recover log-normality, linear rms-flux relations, and radial coherence that would produce inter-band lags. Hence, we successfully relate and connect the phenomenology of propagating fluctuations to modern MHD accretion disk theory.
BAYESIAN ANALYSIS OF TWO STELLAR POPULATIONS IN GALACTIC GLOBULAR CLUSTERS. I. STATISTICAL AND COMPUTATIONAL METHODS
Authors: Stenning D. C. , Wagner-Kaiser R. , Robinson E. , van Dyk D. A. , Hippel T. von , Sarajedini A. , Stein N. 
Published: July 2016

ABSTRACT
We develop a Bayesian model for globular clusters composed of multiple stellar populations, extending earlier statistical models for open clusters composed of simple (single) stellar populations. Specifically, we model globular clusters with two populations that differ in helium abundance. Our model assumes a hierarchical structuring of the parameters in which physical properties—age, metallicity, helium abundance, distance, absorption, and initial mass—are common to (i) the cluster as a whole or to (ii) individual populations within a cluster, or are unique to (iii) individual stars. An adaptive Markov chain Monte Carlo (MCMC) algorithm is devised for model fitting that greatly improves convergence relative to its precursor non-adaptive MCMC algorithm. Our model and computational tools are incorporated into an open-source software suite known as BASE-9. We use numerical studies to demonstrate that our method can recover parameters of two-population clusters, and also show how model misspecification can potentially be identified. As a proof of concept, we analyze the two stellar populations of globular cluster NGC 5272 using our model and methods. (BASE-9 is available from GitHub: https://github.com/argiopetech/base/releases).
BAYESIAN ANALYSIS OF TWO STELLAR POPULATIONS IN GALACTIC GLOBULAR CLUSTERS. II. NGC 5024, NGC 5272, AND NGC 6352
Authors: Wagner-Kaiser R. , Stenning D. C. , Robinson E. , Hippel T. von , Sarajedini A. , Dyk D. A. van , Stein N. , Jefferys W. H. 
Published: July 2016

ABSTRACT
We use Cycle 21 Hubble Space Telescope (HST) observations and HST archival Advanced Camera for Surveys Treasury observations of Galactic Globular Clusters to find and characterize two stellar populations in NGC 5024 (M53), NGC 5272 (M3), and NGC 6352. For these three clusters, both single and double-population analyses are used to determine a best fit isochrone(s). We employ a sophisticated Bayesian analysis technique to simultaneously fit the cluster parameters (age, distance, absorption, and metallicity) that characterize each cluster. For the two-population analysis, unique population level helium values are also fit to each distinct population of the cluster and the relative proportions of the populations are determined. We find differences in helium ranging from ∼0.05 to 0.11 for these three clusters. Model grids with solar α-element abundances ([α/Fe] = 0.0) and enhanced α-elements ([α/Fe] = 0.4) are adopted.
A history of you, me, and humanity: mitochondrial DNA in anthropological research
Authors: Torres Jada Benn 
Published: July 2016

AbstractWithin genetic anthropology, mitochondrial DNA (mtDNA) has garnered a prominent if not enduring place within the anthropological toolkit. MtDNA has provided new and innovative perspectives on the emergence and dispersal of our species, interactions with extinct human species, and illuminated relationships between human groups. In this paper, I provide a brief overview of the major findings ascertained from mtDNA about human origins, human dispersal across the globe, interactions with other hominin species, and the more recent uses of mtDNA in direct to consumer ancestry tests. Relative to nuclear DNA, mtDNA is a small section of the genome and due to its inheritance pattern provides a limited resolution of population history and an individual's genetic ancestry. Consequently, some scholars dismiss mtDNA as insignificant due to the limited inferences that may be made using the locus. Regardless, mtDNA provides some useful insights to understanding how social, cultural, and environmental factors have shaped patterns of genetic variability. Furthermore, with regard to the experiences of historically marginalized groups, in particular those of African descent throughout the Americas, mtDNA has the potential to fill gaps in knowledge that would otherwise remain unknown. Within anthropological sciences, the value of this locus for understanding human experience is maximized when contextualized with complementary lines of evidence.
Instrumentation and measurement strategy for the NOAA SENEX aircraft
campaign as part of the Southeast Atmosphere Study 2013
Authors: Warneke Carsten , Trainer Michael , de Gouw Joost A. , Parrish David D. , Fahey David W. , Ravishankara A. R. , Middlebrook Ann M. , Brock Charles A. , Roberts James M. , Brown Steven S. , Neuman Jonathan A. , Lerner Brian M. , Lack Daniel , Law Daniel , Hübler Gerhard , Pollack Iliana , Sjostedt Steven , Ryerson Thomas B. , Gilman Jessica B. , Liao Jin , Holloway John , Peischl Jeff , Nowak John B. , Aikin Kenneth C. , Min Kyung-Eun , Washenfelder Rebecca A. , Graus Martin G. , Richardson Mathew , Markovic Milos Z. , Wagner Nick L. , Welti André , Veres Patrick R. , Edwards Peter , Schwarz Joshua P. , Gordon Timothy , Dube William P. , McKeen Stuart A. , Brioude Jerome , Ahmadov Ravan , Bougiatioti Aikaterini , Lin Jack J. , Nenes Athanasios , Wolfe Glenn M. , Hanisco Thomas F. , Lee Ben H. , Lopez-Hilfiker Felipe D. , Thornton Joel A. , Keutsch Frank N. , Kaiser Jennifer , Mao Jingqiu , Hatch Courtney D. 
Published: July 2016

Abstract. Natural emissions of ozone-and-aerosol-precursor gases such as isoprene and monoterpenes are high in the southeastern US. In addition, anthropogenic emissions are significant in the southeastern US and summertime photochemistry is rapid. The NOAA-led SENEX (Southeast Nexus) aircraft campaign was one of the major components of the Southeast Atmosphere Study (SAS) and was focused on studying the interactions between biogenic and anthropogenic emissions to form secondary pollutants. During SENEX, the NOAA WP-3D aircraft conducted 20 research flights between 27 May and 10 July 2013 based out of Smyrna, TN. Here we describe the experimental approach, the science goals and early results of the NOAA SENEX campaign. The aircraft, its capabilities and standard measurements are described. The instrument payload is summarized including detection limits, accuracy, precision and time resolutions for all gas-and-aerosol phase instruments. The inter-comparisons of compounds measured with multiple instruments on the NOAA WP-3D are presented and were all within the stated uncertainties, except two of the three NO2 measurements. The SENEX flights included day- and nighttime flights in the southeastern US as well as flights over areas with intense shale gas extraction (Marcellus, Fayetteville and Haynesville shale). We present one example flight on 16 June 2013, which was a daytime flight over the Atlanta region, where several crosswind transects of plumes from the city and nearby point sources, such as power plants, paper mills and landfills, were flown. The area around Atlanta has large biogenic isoprene emissions, which provided an excellent case for studying the interactions between biogenic and anthropogenic emissions. In this example flight, chemistry in and outside the Atlanta plumes was observed for several hours after emission. The analysis of this flight showcases the strategies implemented to answer some of the main SENEX science questions.
A POLÍTICA DE COTAS NA AMÉRICA LATINA COMO IMPULSORA DA REPRESENTAÇÃO FEMININA NA CÂMARA BAIXA
Authors: Da Silva Ellen , Lopes Harvey Isadora 
Published: July 2016

Nos anos 1990, a pressão externa da comunidade internacional, combinada com a pressão interna dos movimentos feministas, gerou ambiente propício para a reflexão de políticas públicas sobre igualdade de gênero em diversos países latino-americanos. Neste contexto, foi gestada a política de cotas legislativas para inclusão de mulheres na política institucional na região. A política de cotas, que teve início na Argentina de 1991, foi implementada nos anos que se seguiram em mais 14 países. É nesse sentido, e a partir de literatura atinente, que o presente trabalho expõe os processos em torno do surgimento de cotas legislativas; assim como seus principais resultados e desafios na mencionada região. A relevância desta empreitada reside na necessidade por um diagnóstico atualizado sobre cotas, em nível regional. Ainda que haja vasta literatura sobre o tema, em sua maioria, versam sobre experiências nacionais. Os resultados encontrados no decorrer deste trabalho apontam que, de modo geral, a representação feminina cresceu nos parlamentos da região. No entanto, aponta também a discrepância de intensidade entre cada país, assim como a predominância de sucesso em democracias que contam com mandatos de posição, magnitude em distrito eleitoral maior e listas fechadas e bloqueadas
From conflict to partnership: growing collaboration between police and NGOs in countries with concentrated epidemics among key populations
Authors: Thomson Nicholas , Riley Diane , Bergenstrom Anne , Carpenter Jenae , Zelitchenko Alex 
Published: July 2016

IntroductionBetween September 2012 and December 2015, a series of national and regional consultations, aimed at resolving a persistent dynamic of conflict between law enforcement agencies (LEAs) and civil society organizations (CSOs) working on issues of access to HIV services in high‐priority countries for people who use drugs have been organized by the HIV/AIDS Section of the United Nations Office on Drugs and Crime, the Joint United Nations Programme on HIV/AIDS, the Law Enforcement and HIV Network (LEAHN) and other international organizations. The aim of these consultations has been to understand, at a national and regional level, the key points of tension between police and CSOs and how to overcome these tensions to enhance access to and uptake of services by key populations, including people who inject drugs, sex workers, men who have sex with men and transgenders. This commentary briefly describes the methods, process, content and key outcomes of these consultations held across diverse number of countries and regions, including Africa, South East Asia, South Asia, Central Asia, Eastern Europe and Latin America.DiscussionWhile the context varies, this paper highlights that there are commonalities that drive a persistent dynamic of conflict and therefore also common methods for resolution of conflict and forging partnerships. Both policing and CSOs have key sectoral responsibilities and reform agendas to implement to ensure that as an individual agency they are able to meet their obligations as partners in the HIV response. Using the key outcomes of discussions and recommendations from these consultations and drawing on existing literature, the objective of this paper is to present a preliminary model that roadmaps the critical path from resolution of conflict to partnership between LEAs and CSOs.ConclusionsThis paper seeks to highlight that critical resources are required to support ongoing development and harnessing of partnerships between LEAs and CSOs and argues that these resources should not just come from global HIV funding mechanisms but should be part of a more mainstreamed security sector reform agenda that understands the mutual benefits that programming for human rights–based policing reform would have on HIV, development and security.
Impact of climate variability on the tidal oceanic magnetic signal—A model‐based sensitivity study
Authors: Saynisch J. , Petereit J. , Irrgang C. , Kuvshinov A. , Thomas M. 
Published: July 2016

AbstractESA's satellite magnetometer mission Swarm is supposed to lower the limit of observability for oceanic processes. While periodic magnetic signals from ocean tides are already detectable in satellite magnetometer observations, changes in the general ocean circulation are yet too small or irregular for a successful separation. An approach is presented that utilizes the good detectability of tidal magnetic signals to detect changes in the oceanic electric conductivity distribution. Ocean circulation, tides, and the resultant magnetic fields are calculated with a global general ocean circulation model coupled to a 3‐D electromagnetic induction model. For the decay of the meridional overturning circulation, as an example, the impact of climate variability on tidal oceanic magnetic signals is demonstrated. Total overturning decay results in anomalies of up to 0.7 nT in the radial magnetic M2 signal at sea level. The anomalies are spatially heterogeneous and reach in extended areas 30% or more of the unperturbed tidal magnetic signal. The anomalies should be detectable in long time series from magnetometers on land or at the ocean bottom. The anomalies at satellite height (430 km) reach 0.1 nT and pose a challenge for the precision of the Swarm mission. Climate variability induced deviations in the tide system (e.g., tidal velocities and phases) are negligible. Changes in tidal magnetic fields are dominated by changes in seawater salinity and temperature. Therefore, it is concluded that observations of tidal magnetic signals could be used as a tool to detect respective state changes in the ocean.
Convective vortices and dust devils at the MSL landing site: Annual variability
Authors: Kahanpää H. , Newman C. , Moores J. , Zorzano M.‐P. , Martín‐Torres J. , Navarro S. , Lepinette A. , Cantor B. , Lemmon M. T. , Valentín‐Serrano P. , Ullán A. , Schmidt W. 
Published: July 2016

AbstractTwo hundred fifty‐two transient drops in atmospheric pressure, likely caused by passing convective vortices, were detected by the Rover Environmental Monitoring Station instrument during the first Martian year of the Mars Science Laboratory (MSL) landed mission. These events resembled the vortex signatures detected by the previous Mars landers Pathfinder and Phoenix; however, the MSL observations contained fewer pressure drops greater than 1.5 Pa and none greater than 3.0 Pa. Apparently, these vortices were generally not lifting dust as only one probable dust devil has been observed visually by MSL. The obvious explanation for this is the smaller number of strong vortices with large central pressure drops since according to Arvidson et al. [] ample dust seems to be present on the surface. The annual variation in the number of detected convective vortices followed approximately the variation in Dust Devil Activity (DDA) predicted by the MarsWRF numerical climate model. This result does not prove, however, that the amount of dust lifted by dust devils would depend linearly on DDA, as is assumed in several numerical models of the Martian atmosphere, since dust devils are only the most intense fraction of all convective vortices on Mars, and the amount of dust that can be lifted by a dust devil depends on its central pressure drop. Sol‐to‐sol variations in the number of vortices were usually small. However, on 1 Martian solar day a sudden increase in vortex activity, related to a dust storm front, was detected.