bluuebunny/crossref_metadata_2025_split huggingface dataset:
Kinematics of Circumgalactic Gas: Feeding Galaxies and Feedback
Authors: Martin Crystal L. , Ho Stephanie H. , Kacprzak Glenn G. , Churchill Christopher W. 
Published: June 2019

Abstract
We present observations of 50 pairs of redshift z ≈ 0.2 star-forming galaxies and background quasars. These sightlines probe the circumgalactic medium (CGM) out to half the virial radius, and we describe the circumgalactic gas kinematics relative to the reference frame defined by the galactic disks. We detect halo gas in Mg ii absorption, measure the equivalent-width-weighted Doppler shifts relative to each galaxy, and find that the CGM has a component of angular momentum that is aligned with the galactic disk. No net counter-rotation of the CGM is detected within 45° of the major axis at any impact parameter. The velocity offset of the circumgalactic gas correlates with the projected rotation speed in the disk plane out to disk radii of roughly 70 kpc. We confirm previous claims that the Mg ii absorption becomes stronger near the galactic minor axis, and we show that the equivalent width correlates with the velocity range of the absorption. We cannot directly measure the location of any absorber along the sightline, but we explore the hypothesis that individual velocity components can be associated with gas orbiting in the disk plane or flowing radially outward in a conical outflow. We conclude that centrifugal forces partially support the low-ionization gas and galactic outflows kinematically disturb the CGM producing excess absorption. Our results firmly rule out schema for the inner CGM that lack rotation and suggest that angular momentum as well as galactic winds should be included in any viable model for the low-redshift CGM.
On the Fallback Disk around the Slowest Isolated Pulsar, 1E 161348-5055
Authors: Xu Kun , Li Xiang-Dong 
Published: June 2019

Abstract
The central compact object 1E 161348−5055 in the supernova remnant RCW 103 has a spin period ∼6.67 hr, making it the slowest isolated pulsar. It is believed that a supernova fallback disk is required to spin down the neutron star (NS) to the current spin period within a few thousand years. The mass of the fallback disk around newborn NSs can provide useful information on the supernova processes and the possible detection limit with optical/infrared observations. However, it is controversial how massive the disk is in the case of 1E 161348−5055. In this work we simulate the spin evolution of a magnetar that is driven by an interaction between the disk and the star’s magnetic field. Compared with previous studies, we take into account various critical conditions that affect the formation and evolution of the fallback disk. Our calculation shows that we can reproduce the extremely slow spin of 1E 161348−5055 when taking the initial disk mass M
d ∼ 10−7
M
⊙ and the NS magnetic field B ≥ 5 × 1015 G. This implies that 1E 161348−5055 may be a magnetar with very special initial parameters. However, if future observations reveal more objects like 1E 161348−5055, then stringent constraints can be placed on the supernova fallback.
Evolution of Three-dimensional Relativistic Ion Weibel Instability: Competition with Kink Instability
Authors: Takamoto Makoto , Matsumoto Yosuke , Kato Tsunehiko N. 
Published: June 2019

Abstract
In this paper, we report our recent findings on the relativistic Weibel instability and its nonlinear saturation by performing numerical simulations of collisionless plasmas. Analysis of the obtained numerical results revealed that the nonlinear phase of the Weibel instability can be described by characteristic phases based on the Weibel filaments’ current density in terms of particle and Alfvén limit currents. We also analyzed the relativistic kink instability based on the energy principle in the magnetohydrodynamic (MHD) regime, and found that the Weibel filaments do not suffer from the kink-type instability in the MHD regime up to 1000

. This finding allowed a magnetic field to be sustained by relativistic Weibel instability that was stable enough to be a seed for MHD dynamos.
ALMA Reveals Kinematics of Super Star Cluster Candidate H72.97-69.39 in LMC-N79
Authors: Nayak O. , Meixner M. , Sewiło M. , Ochsendorf B. , Bolatto A. , Indebetouw R. , Kawamura A. , Onishi T. , Fukui Y. 
Published: June 2019

Abstract
Conditions in super star clusters (SSCs) lead to the formation of dozens of massive stars in close proximity. However, SSCs are rare in the local universe. H72.97-69.39, located in the N79 region of the Large Magellanic Cloud (LMC), is an SSC candidate. In this paper we report the ALMA observations of the potential SSC. ALMA reveals colliding filaments, outflows, an H ii region, and a C ii region associated with this cluster. The timescale of the outflow is 65,000 yr, which is consistent with this being a young cluster. The molecular gas around this potential early-stage SSC candidate is complex in nature on small scales (as seen with ALMA) and large scales (as seen with Herschel).
Evolution of Helium Star–White Dwarf Binaries Leading up to Thermonuclear Supernovae
Authors: Wong Tin Long Sunny , Schwab Josiah 
Published: June 2019

Abstract
We perform binary evolution calculations on helium star—carbon–oxygen white dwarf (CO WD) binaries, using the stellar evolution code MESA. This single degenerate channel may contribute significantly to thermonuclear supernovae at short delay times. We examine the thermal-timescale mass transfer from a 1.1 to 2.0

helium star to a 0.90–1.05

CO WD for initial orbital periods in the range 0.05–1 day. Systems in this range may produce a thermonuclear supernova, helium novae, a helium star—oxygen–neon WD binary, or a detached double CO WD binary. Our time-dependent calculations that resolve the stellar structures of both binary components allow accurate distinction between the eventual formation of a thermonuclear supernova (via central ignition of carbon burning) and that of an ONe WD (in the case of off-center ignition). Furthermore, we investigate the effect of a slow WD wind, which implies a specific angular momentum loss from the binary that is larger than typically assumed. We find that this does not significantly alter the region of parameter space over which systems evolve toward thermonuclear supernovae. Our determination of the correspondence between initial binary parameters and the final outcome informs population synthesis studies of the contribution of the helium donor channel to thermonuclear supernovae. In addition, we constrain the orbital properties and observable stellar properties of the progenitor binaries of thermonuclear supernovae and helium novae.
On the Elevation and Suppression of Star Formation within Galaxies
Authors: Wang Enci , Lilly Simon J. , Pezzulli Gabriele , Matthee Jorryt 
Published: June 2019

Abstract
To understand star formation in galaxies, we investigate the star formation rate (SFR) surface density (

) profiles for galaxies, based on a well-defined sample of 976 star-forming MaNGA galaxies. We find that the typical

profiles within 1.5

of normal SF galaxies can be well described by an exponential function for different stellar mass intervals, while the sSFR profile shows positive gradients, especially for more massive SF galaxies. This is due to the more pronounced central cores or bulges, rather than the onset of a “quenching” process. While galaxies that lie significantly above (or below) the star formation main sequence show overall an elevation (or suppression) of

at all radii, this central elevation (or suppression) is more pronounced in more massive galaxies. The degree of central enhancement and suppression is quite symmetric, suggesting that both the elevation and suppression of star formation are following the same physical processes. Furthermore, we find that the dispersion in

within and across the population is found to be tightly correlated with the inferred gas depletion time, whether based on the stellar surface mass density or the orbital dynamical time. This suggests that we are seeing the response of a simple gas-regulator system to variations in the accretion rate. This is explored using a heuristic model that can quantitatively explain the dependence of σ(

) on gas depletion timescale. Variations in accretion rate are progressively more damped out in regions of low star formation efficiency, leading to a reduced amplitude of variations in star formation.
Rocky Planetesimal Formation Aided by Organics
Authors: Homma Kazuaki A. , Okuzumi Satoshi , Nakamoto Taishi , Ueda Yuta 
Published: June 2019

Abstract
The poor stickiness of silicate dust grains is a major obstacle to the formation of rocky planetesimals. In this study, we examine the possibility that silicate grains with an organic mantle, which we call Organic-mantled Grains (OMGs), form planetesimals through direct coagulation. Organic mantles are commonly found in interplanetary dust particles, and laboratory experiments show that they are softer than silicates, in particular in warm environments. This, combined with the theory of particle adhesion, implies that OMGs are stickier than bare silicate grains. Because organic mantles can survive up to 400 K, silicate grains inside the water snow line in protoplanetary disks can in principle hold such mantles. We construct a simple grain adhesion model to estimate the threshold collision velocity below which aggregates of OMGs can grow. The model shows that aggregates of 0.1 μm-sized OMGs can overcome the fragmentation barrier in protoplanetary disks if the mantles are as thick as those in interplanetary dust particles and if the temperature is above ∼200 K. We use this adhesion model to simulate the global evolution of OMG aggregates in the inner part of a protoplanetary disk, demonstrating that OMG aggregates can indeed grow into planetesimals under favorable conditions. Because organic matter is unstable at excessively high temperatures, rocky planetesimal formation by the direct sticking of OMGs is expected to occur in a disk annulus corresponding to the temperature range ∼200–400 K. The organic-rich planetesimals may grow into carbon-poor rocky planetesimals by accreting a large amount of carbon-poor chondrules.
Origin of the CEMP-no Group Morphology in the Milky Way
Authors: Yoon Jinmi , Beers Timothy C. , Tian Di , Whitten Devin D. 
Published: June 2019

Abstract
The elemental-abundance signatures of the very first stars are imprinted on the atmospheres of CEMP-no stars, as various evidence suggests they are bona fide second-generation stars. It has recently been recognized that the CEMP-no stars can be subdivided into at least two groups, based on their distinct morphology in the A(C)–[Fe/H] space, indicating the likely existence of multiple pathways for their formation. In this work, we compare the halo CEMP-no group morphology with that of stars found in satellite dwarf galaxies of the Milky Way—a very similar A(C)–[Fe/H] pattern is found, providing clear evidence that halo CEMP-no stars were indeed accreted from their host mini-halos, similar in nature to those that formed in presently observed ultra-faint dwarfs (UFDs) and dwarf spheroidal (dSph) galaxies. We also infer that the previously noted “anomalous” CEMP-no halo stars (with high A(C) and low [Ba/Fe] ratios) that otherwise would be associated with Group I may have the same origin as the Group III CEMP-no halo stars, by analogy with the location of several Group III CEMP-no stars in the UFDs and dSphs and their distinct separation from that of the CEMP-s stars in the A(Ba)–A(C) space. Interestingly, CEMP-no stars associated with UFDs include both Group II and Group III stars, while the more massive dSphs appear to have only Group II stars. We conclude that understanding the origin of the CEMP-no halo stars requires knowledge of the masses of their parent mini-halos, which is related to the amount of carbon dilution prior to star formation, in addition to the nature of their nucleosynthetic origin.
The Effective Surface Area of Amorphous Solid Water Measured by the Infrared Absorption of Carbon Monoxide
Authors: He Jiao , Clements Aspen R. , Emtiaz SM , Toriello Francis , Garrod Robin T. , Vidali Gianfranco 
Published: June 2019

Abstract
The need to characterize ices coating dust grains in dense interstellar clouds arises from the importance of ice morphology in facilitating the diffusion and storage of radicals and reaction products in ices, a well-known place for the formation of complex molecules. Yet, there is considerable uncertainty about the structure of interstellar medium ices, their ability to store volatiles, and under what conditions. We measured the infrared absorption spectra of CO on the pore surface of porous amorphous solid water (ASW), and quantified the effective pore surface area of ASW. Additionally, we present results obtained from a Monte Carlo model of ASW in which the morphology of the ice is directly visualized and quantified. We found that 200 ML of ASW annealed to 20 K has a total pore surface area that is equivalent to 46 ML. This surface area decreases linearly with temperature to about 120 K. We also found that (1) dangling OH bonds only exist on the surface of pores; (2) almost all of the pores in the ASW are connected to the vacuum–ice interface, and are accessible for adsorption of volatiles from the gas phase; there are few closed cavities inside ASW at least up to a thickness of 200 ML; (3) the total pore surface area is proportional to the total three-coordinated water molecules in the ASW in the temperature range 60–120 K. We also discuss the implications on the structure of ASW and surface reactions in the ice mantle in dense clouds.
Public Release of RELXILL_NK: A Relativistic Reflection Model for Testing Einstein’s Gravity
Authors: Abdikamalov Askar B. , Ayzenberg Dimitry , Bambi Cosimo , Dauser Thomas , García Javier A. , Nampalliwar Sourabh 
Published: June 2019

Abstract
We present the public release version of relxill_nk, an X-ray reflection model for testing the Kerr hypothesis and general relativity. This model extends the relxill model that assumes the black hole (BH) spacetime is described by the Kerr metric. We also present relxilllp_nk, the first non-Kerr X-ray reflection model with a lamppost corona configuration, as well as all other models available in the full relxill_nk package. In all models the relevant relativistic effects are calculated through a general relativistic ray-tracing code that can be applied to any well-behaved, stationary, axisymmetric, and asymptotically flat BH spacetime. We show that the numerical error introduced by using a ray-tracing code is not significant compared with the observational error present in current X-ray reflection spectrum observations. In addition, we present the reflection spectrum for the Johannsen metric as calculated by relxill_nk.
How Bright Are Fast Optical Bursts Associated With Fast Radio Bursts?
Authors: Yang Yuan-Pei , Zhang Bing , Wei Jian-Yan 
Published: June 2019

Abstract
The origin of fast radio bursts (FRBs) is still unknown. Multiwavelength observations during or shortly after the FRB phase would be essential to identify the counterpart of an FRB and to constrain its progenitor and environment. In this work, we investigate the brightness of the “fast optical bursts” (FOBs) associated with FRBs and the prospects of detecting them. We investigate several inverse Compton (IC) scattering processes that might produce an FOB, including both the one-zone and two-zone models. We also investigate the extension of the same mechanism of FRB emission to the optical band. We find that a detectable FOB with the current and forthcoming telescopes is possible under the IC scenarios with very special conditions. In particular, the FRB environment would need to invoke a neutron star with an extremely strong magnetic field and an extremely fast spin, or an extremely young supernova remnant surrounding the FRB source. Furthermore, most electrons in the source are also required to have a fine-tuned energy distribution such that most of the IC energy is channeled in the optical band. We conclude that the prospect of detecting FOBs associated with FRBs is low. On the other hand, if FOBs are detected from a small fraction of FRBs, these FOBs would reveal extreme physical conditions in the FRB environments.
The Effect of Minor and Major Mergers on the Evolution of Low-excitation Radio Galaxies
Authors: Gordon Yjan A. , Pimbblet Kevin A. , Kaviraj Sugata , Owers Matt S. , O’Dea Christopher P. , Walmsley Mike , Baum Stefi A. , Crossett Jacob P. , Fraser-McKelvie Amelia , Lintott Chris J. , Pierce Jonathon C. S. 
Published: June 2019

Abstract
We use deep, μ

r
≲ 28 mag arcsec−2, r-band imaging from the Dark Energy Camera Legacy Survey to search for past, or ongoing, merger activity in a sample of 282 low-excitation radio galaxies (LERGs) at z < 0.07. Our principal aim is to assess the the role of mergers in the evolution of LERGs. Exploiting the imaging depth, we classify tidal remnants around galaxies as both minor and major morphological disturbances for our LERG sample and 1622 control galaxies matched in redshift, stellar mass, and environment. In groups and in the field, the LERG minor merger fraction is consistent with the control population. In galaxy clusters, 8.8 ± 2.9% of LERGs show evidence of recent minor mergers in contrast to 23.0 ± 2.0% of controls. This ∼4σ deficit of minor mergers in cluster LERGs suggests these events may inhibit this type of nuclear activity for galaxies within the cluster environment. We observe a >4σ excess of major mergers in the LERGs with M
* ≲ 1011 M⊙, with 10 ± 1.5% of these active galactic nuclei involved in such large-scale interactions compared to 3.2 ± 0.4% of control galaxies. This excess of major mergers in LERGs decreases with increasing stellar mass, vanishing by M
* > 1011.3 M⊙. These observations show that minor mergers do not fuel LERGs, and are consistent with typical LERGs being powered by accretion of matter from their halo. Where LERGs are associated with major mergers, these objects may evolve into more efficiently accreting active galactic nuclei as the merger progresses and more gas falls on to the central engine.
A Physical Basis for the H-band Blue-edge Velocity and Light-curve Shape Correlation in Context of Type Ia Supernova Explosion Physics
Authors: Ashall C. , Hoeflich P. , Hsiao E. Y. , Phillips M. M. , Stritzinger M. , Baron E. , Piro A. L. , Burns C. , Contreras C. , Davis S. , Galbany L. , Holmbo S. , Kirshner R. P. , Krisciunas K. , Marion G. H. , Morrell N. , Sand D. J. , Shahbandeh M. , Suntzeff N. B. , Taddia F. 
Published: June 2019

Abstract
Our recent work demonstrates a correlation between the high-velocity blue edge, v
edge, of the iron-peak Fe/Co/Ni H-band emission feature and the optical light-curve (LC) shape of normal, transitional and subluminous SNe Ia. We explain this correlation in terms of SN Ia physics. v
edge corresponds to the sharp transition between the complete and incomplete silicon burning regions in the ejecta. It measures the point in velocity space where the outer 56Ni mass fraction, X
Ni, falls to the order of 0.03–0.10. For a given 56Ni mass, M(56Ni), v
edge is sensitive to the specific kinetic energy E
kin(M(56Ni)/M
WD) of the corresponding region. Combining v
edge with LC parameters (i.e., s

BV
,

in B and V) allows us to distinguish between explosion scenarios. The correlation between v
edge and light-curve shape is consistent with explosion models near the Chandrasekhar limit. However, the available sub-M
Ch WD explosion model based on SN 1999by exhibits velocities that are too large to explain the observations. Finally, the subluminous SN 2015bo exhibits signatures of a dynamical merger of two WDs demonstrating diversity among explosion scenarios at the faint end of the SNe Ia population.
A Proposed Metadata Standard for Recording and Sharing Attribution Information in Biodiversity
Authors: Thessen Anne , Shorthouse David , Paul Deborah , Conlon Michael , Woodburn Matt , Koureas Dimitrios , Ramdeen Sarah , Haak Laurel , Cornwell Peter 
Published: June 2019

Research collections are an important tool for understanding the Earth, its systems, and human interaction. Despite the importance of collections, many are not maintained or curated as thoroughly as we would like. Part of the reason for this is the lack of professional reward for collection, curation, or maintenance. To address this gap in attribution metadata, the Research Data Alliance (RDA) and the Biodiversity Information Standards (TDWG) organization co-endorsed a Working Group to create recommendations for the representation of attribution metadata. After 18 months, this Working Group recommended a very simple data exchange standard to link people, the curatorial actions they perform, and the digital or physical objects they are curating. These recommendations are discussed in the context of community-developed use cases. Future work includes:

exploration of a Darwin Core extension,

best practices on how to best adopt these recommendations, and

possible solutions to help accelerate the process of connecting people and their activities in legacy and future data.

exploration of a Darwin Core extension,
best practices on how to best adopt these recommendations, and
possible solutions to help accelerate the process of connecting people and their activities in legacy and future data.
To explore options for making collections work more visible and citable, we tested the use of digital annotation tools and person identifiers in curation workflows. The results from this pilot project in collaboration with ORCID and Data Futures to display specimens on an ORCID profile will be presented.
Next Steps in Data Capture from Specimen Labels and Data Integration: Lessons learnt from the ICEDIG pilots
Authors: Dillen Mathias , Groom Quentin , Phillips Sarah , Spasic Irena 
Published: June 2019

The rapid development and refinement of digital technologies in the last two decades has spearheaded a wave of digitization in natural history collections. This has generated a massive number of digitized images and many more are expected with the planned European Distributed Systems of Scientific Collections (DiSSCo) infrastructure. Many of these images will contain labels with data written on them, typed on them or interpretable from them, but capturing these data remains a challenge. Automated as well as manual methods are being investigated and have yielded mixed results. In addition, previously captured data or data to be captured this way will need to be interoperable in order to make digital access and enrichment most effective. Finally, institutions holding the physical specimens will need to remain capable of efficiently curating the digital, potentially annotated, counterparts. This will require compatibility with the diverse data models of local Collection Management Systems (CMS).
In the context of the ICEDIG (Innovation and consolidation for large scale digitisation of natural heritage) project, a benchmark dataset of herbarium specimens was assembled from nine contributing institutions (Dillen et al. 2019). This dataset was used to evaluate automated methods of text recognition, such as OCR (Optical Character Recognition) and HTR (Handwritten Text Recognition), and post-capture classification, such as language identification or NER (Named Entity Recognition). A pipeline from scan to scientifically useful data was drafted and guidelines for selecting appropriate software solutions were provided.
The benchmark dataset was also processed through multiple crowdsourcing platforms, after which the quality and interoperability of the resulting transcriptions was analyzed. The aptitude of local Collection Management Systems to curate these digitized specimens efficiently was investigated, as well as the fitness of data standards in use to ensure and maintain proper interoperability. In addition, available surveys on CMS use and satisfaction were summarized and in-depth assessments of the CMS in use at the ICEDIG partner institutes were performed. A summary of results and recommendations will be presented.