{"results":[{"id":"arxiv_2603.25848","title":"The Hubble Missing Globular Cluster Survey. III. Astro-photometric catalogs, artificial-star tests, and improved absolute proper motions","authors":[{"name":"M. Libralato"},{"name":"A. Bellini"},{"name":"D. Massari"},{"name":"M. Bellazzini"},{"name":"F. Aguado-Agelet"},{"name":"S. Cassisi"},{"name":"E. Ceccarelli"},{"name":"E. Dalessandro"},{"name":"E. Dodd"},{"name":"F. R. Ferraro"},{"name":"C. Gallart"},{"name":"B. Lanzoni"},{"name":"M. Monelli"},{"name":"A. Mucciarelli"},{"name":"E. Pancino"},{"name":"R. Pascale"},{"name":"L. Rosignoli"},{"name":"M. Salaris"},{"name":"S. Saracino"},{"name":"C. Zerbinati"}],"abstract":"The Hubble Missing Globular Cluster Survey (MGCS) has taken one of the last opportunities to complete the census of Galactic globular clusters (GCs) started by past Hubble Space Telescope (HST) programs, securing high-resolution data for 34 GCs never observed before by HST. The previous papers of the series have highlighted the astrometric and photometric potential of the project by analyzing a subsample of targets. We present, and release to the community, the official astro-photometric catalogs of the MGCS for all GCs imaged by this project. We describe the data reduction using state-of-the-art techniques designed for HST. We discuss the photometric calibration and show, for the first time, the synergy with the Gaia catalog to ensure homogeneous photometry across our data set. We compute artificial-star tests that can be used to assess systematics and the completeness level of our data. We combined HST and Gaia data to refine the absolute PMs of our GCs, reaching a precision $\\sim$3 times better than that of Gaia alone. We used these new PMs to update (and to determine for the first time for six systems) the associations between GCs and their putative galaxy progenitors. This work continues decades-long efforts of large Treasury programs in sharing precise and accurate atlases to the community for studying GCs across a wide range of scientific endeavors.","source":"arXiv","year":2026,"language":"en","subjects":["astro-ph.GA","astro-ph.IM","astro-ph.SR"],"url":"https://arxiv.org/abs/2603.25848","pdf_url":"https://arxiv.org/pdf/2603.25848","is_open_access":true,"published_at":"2026-03-26T19:14:41Z","score":70},{"id":"arxiv_2509.20531","title":"Blue Stragglers and Friends: Initial Evolutionary Pathways in Close Low-Mass Binaries: Literature Review","authors":[{"name":"Robert D. Mathieu"},{"name":"Onno R. Pols"}],"abstract":"The scope of this literature review is observations of the products of first-stage evolution for binaries having components with M \u003c 2 $M_\\odot$. A taxonomy for these products comprises dwarfs (\"blue stragglers\"), giants (\"yellow stragglers\"), subdwarf B stars, and giant-like stars (\"sub-subgiants\" and \"red stragglers\"). This literature review is organized according to this taxonomy within three distinct environments: open star clusters, globular star clusters, and the Galactic field.   This literature review is the Supplemental Material for Blue Stragglers and Friends: Initial Evolutionary Pathways in Close Low-Mass Binaries (Mathieu \u0026 Pols, 2025, ARAA, 63:467-512, doi: www.annualreviews.org/content/journals/10.1146/annurev-astro-071221-054402). It is intended to support and expand on Section 3 of the main text of this Annual Review of Astronomy and Astrophysics, where an integrated perspective on the common and contrasting astrophysical properties of these binary evolution products is provided. Figures used in the main text to highlight key observational results are referenced in this literature review.   The closing date of this review is January 17, 2025, with some citations subsequently updated.","source":"arXiv","year":2025,"language":"en","subjects":["astro-ph.SR","astro-ph.GA"],"doi":"10.1146/annurev-astro-071221-054402","url":"https://arxiv.org/abs/2509.20531","pdf_url":"https://arxiv.org/pdf/2509.20531","is_open_access":true,"published_at":"2025-09-24T20:02:18Z","score":69},{"id":"arxiv_2506.06115","title":"Testing OH Megamaser Identification Methods in HI Surveys: Updated Source-Flagging Algorithms and New Detections in ALFALFA","authors":[{"name":"Hayley Roberts"},{"name":"Jeremy Darling"},{"name":"Kelley M. Hess"},{"name":"Andrew J. Baker"},{"name":"Elizabeth A. K. Adams"},{"name":"Helga Dénes"}],"abstract":"OH megamasers (OHMs) are extragalactic masers found primarily in gas-rich galaxy major mergers. To date, only $\\sim$120 OHMs have been cataloged since their discovery in 1982, and efforts to identify distinct characteristics of OHM host galaxies have remained inconclusive. As radio astronomy advances with next-generation telescopes and extensive 21 cm HI surveys, precursors to the Square Kilometre Array (SKA) are expected to detect the 18 cm OH masing line with significantly increased frequency, potentially expanding the known OHM population tenfold. These detections, however, risk confusion with lower-redshift HI emitters unless accompanied by independent spectroscopic redshifts. Building on methods proposed by Roberts et al. (arXiv:2102.12486) for distinguishing these interloping OHMs via near- to mid-IR photometry and emission line frequencies, we apply these techniques to data from the Arecibo Legacy Fast ALFA [Arecibo L-band Feed Array] (ALFALFA) survey and a preliminary APERture Tile In Focus (Apertif) HI emission line catalog from the Westerbork Synthesis Radio Telescope. Our study, utilizing the Apache Point Observatory 3.5m telescope to obtain optical spectroscopic redshifts of 142 candidates (107 from ALFALFA and 35 from Apertif), confirms five new OHM host galaxies and reidentifies two previously catalogued OHMs misclassified as HI emitters in ALFALFA. These findings support the predictions from Roberts et al. (arXiv:2102.12486 [astro-ph.GA]) and underscore the evolving landscape of radio astronomy in the context of next-generation telescopes.","source":"arXiv","year":2025,"language":"en","subjects":["astro-ph.GA"],"doi":"10.3847/1538-4357/adcedc","url":"https://arxiv.org/abs/2506.06115","pdf_url":"https://arxiv.org/pdf/2506.06115","is_open_access":true,"published_at":"2025-06-06T14:25:02Z","score":69},{"id":"crossref_10.21070/ups.8652","title":"E-Comic Astro Kids Explore Milky Way","authors":[{"name":"Febi Talitha Salsabila"},{"name":"Machful Indrakurniawan"}],"abstract":"","source":"CrossRef","year":2025,"language":"en","subjects":null,"doi":"10.21070/ups.8652","url":"https://doi.org/10.21070/ups.8652","is_open_access":true,"published_at":"","score":69},{"id":"arxiv_2409.06774","title":"JWST imaging of the closest globular clusters -- IV. Chemistry, luminosity, and mass functions of the lowest-mass members in the NIRISS parallel fields","authors":[{"name":"M. Libralato"},{"name":"R. Gerasimov"},{"name":"L. Bedin"},{"name":"J. Anderson"},{"name":"D. Apai"},{"name":"A. Bellini"},{"name":"A. J. Burgasser"},{"name":"M. Griggio"},{"name":"D. Nardiello"},{"name":"M. Salaris"},{"name":"M. Scalco"},{"name":"E. Vesperini"}],"abstract":"We present observations of the two closest globular clusters, NGC 6121 and NGC 6397, taken with the NIRISS detector of JWST. The combination of our new JWST data with archival Hubble Space Telescope (HST) images allows us to compute proper motions, disentangle cluster members from field objects, and probe the main sequence (MS) of the clusters down to \u003c0.1 $M_\\odot$ as well as the brighter part of the white-dwarf sequence. We show that theoretical isochrones fall short in modeling the low-mass MS and discuss possible explanations for the observed discrepancies. Our analysis suggests that the lowest-mass members of both clusters are significantly more metal-rich and oxygen-poor than their higher-mass counterparts. It is unclear whether the difference is caused by a genuine mass-dependent chemical heterogeneity, low-temperature atmospheric processes altering the observed abundances, or systematic shortcomings in the models. We computed the present-day local luminosity and mass functions of the two clusters; our data reveal a strong flattening of the mass function indicative of a significant preferential loss of low-mass stars in agreement with previous dynamical models for these two clusters. We have made our NIRISS astro-photometric catalogs and stacked images publicly available to the community.","source":"arXiv","year":2024,"language":"en","subjects":["astro-ph.SR","astro-ph.GA"],"url":"https://arxiv.org/abs/2409.06774","pdf_url":"https://arxiv.org/pdf/2409.06774","is_open_access":true,"published_at":"2024-09-10T18:00:01Z","score":68},{"id":"arxiv_2406.17347","title":"Hubble Space Telescope proper motions of Large Magellanic Cloud star clusters -- I. Catalogues and results for NGC 1850","authors":[{"name":"F. Niederhofer"},{"name":"A. Bellini"},{"name":"V. Kozhurina-Platais"},{"name":"M. Libralato"},{"name":"M. Häberle"},{"name":"N. Kacharov"},{"name":"S. Kamann"},{"name":"N. Bastian"},{"name":"I. Cabrera-Ziri"},{"name":"M. -R. L. Cioni"},{"name":"F. Dresbach"},{"name":"S. Martocchia"},{"name":"D. Massari"},{"name":"S. Saracino"}],"abstract":"We present proper motion (PM) measurements for a sample of 23 massive star clusters within the Large Magellanic Cloud using multi-epoch data from the Hubble Space Telescope (HST). We combined archival data from the ACS/WFC and WFC3/UVIS instruments with observations from a dedicated HST programme, resulting in time baselines between 4.7 and 18.2 yr available for PM determinations. For bright well-measured stars, we achieved nominal PM precisions of 55 $μ$as/yr down to 11 $μ$as/yr . To demonstrate the potential and limitations of our PM data set, we analysed the cluster NGC 1850 and showcase a selection of different science applications. The precision of the PM measurements allows us to disentangle the kinematics of the various stellar populations that are present in the HST field. The cluster has a centre-of-mass motion that is different from the surrounding old field stars and also differs from the mean motion of a close-by group of very young stars. We determined the velocity dispersion of field stars to be 0.128 +/- 0.003 mas/yr (corresponding to 30.3 +/- 0.7 km/s). The velocity dispersion of the cluster inferred from the PM data set most probably overestimates the true value, suggesting that the precision of the measurements at this stage is not sufficient for a reliable analysis of the internal kinematics of extra-galactic star clusters. Finally, we exploit the PM-cleaned catalogue of likely cluster members to determine any radial segregation between fast and slowly-rotating stars, finding that the former are more centrally concentrated. With this paper, we also release the astro-photometric catalogues for each cluster.","source":"arXiv","year":2024,"language":"en","subjects":["astro-ph.GA"],"url":"https://arxiv.org/abs/2406.17347","pdf_url":"https://arxiv.org/pdf/2406.17347","is_open_access":true,"published_at":"2024-06-25T08:01:14Z","score":68},{"id":"arxiv_2208.10656","title":"Deblurring galaxy images with Tikhonov regularization on magnitude domain","authors":[{"name":"Kazumi Murata"},{"name":"Tsutomu T. Takeuchi"}],"abstract":"We propose a regularization-based deblurring method that works efficiently for galaxy images. The spatial resolution of a ground-based telescope is generally limited by seeing conditions and much worse than space-based telescopes. This circumstance has generated considerable research interest in restoration of spatial resolution. Since image deblurring is a typical inverse problem and often ill-posed, solutions tend to be unstable. To obtain a stable solution, much research has adopted regularization-based methods for image deblurring, but the regularization term is not necessarily appropriate for galaxy images. Although galaxies have an exponential or Sersic profile, the conventional regularization assumes the image profiles to behave linear in space. The significant deviation between the assumption and real situation leads to blurring the images and smoothing out the detailed structures. Clearly, regularization on logarithmic, i.e. magnitude domain, should provide a more appropriate assumption, which we explore in this study. We formulate a problem of deblurring galaxy images by an objective function with a Tikhonov regularization term on magnitude domain. We introduce an iterative algorithm minimizing the objective function with a primal-dual splitting method. We investigate the feasibility of the proposed method using simulation and observation images. In the simulation, we blur galaxy images with a realistic point spread function and add both Gaussian and Poisson noises. For the evaluation with the observed images, we use galaxy images taken by the Subaru HSC-SSP. Both of these evaluations show that our method successfully recovers the spatial resolution of the images and significantly outperforms the conventional methods. The code is publicly available from the Github ( https://github.com/kzmurata-astro/PSFdeconv_amag ).","source":"arXiv","year":2022,"language":"en","subjects":["astro-ph.IM","astro-ph.GA"],"doi":"10.1093/pasj/psac071","url":"https://arxiv.org/abs/2208.10656","pdf_url":"https://arxiv.org/pdf/2208.10656","is_open_access":true,"published_at":"2022-08-23T00:16:01Z","score":66},{"id":"arxiv_2206.09924","title":"The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XXIII. Proper-motion catalogs and internal kinematics","authors":[{"name":"M. Libralato"},{"name":"A. Bellini"},{"name":"E. Vesperini"},{"name":"G. Piotto"},{"name":"A. P. Milone"},{"name":"R. P. van der Marel"},{"name":"J. Anderson"},{"name":"A. Aparicio"},{"name":"B. Barbuy"},{"name":"L. R. Bedin"},{"name":"L. Borsato"},{"name":"S. Cassisi"},{"name":"E. Dalessandro"},{"name":"F. R. Ferraro"},{"name":"I. R. King"},{"name":"B. Lanzoni"},{"name":"D. Nardiello"},{"name":"S. Ortolani"},{"name":"A. Sarajedini"},{"name":"S. T. Sohn"}],"abstract":"A number of studies based on data collected by the $\\textit{Hubble Space Telescope}$ ($\\textit{HST}$) GO-13297 program \"HST Legacy Survey of Galactic Globular Clusters: Shedding UV Light on Their Populations and Formation\" have investigated the photometric properties of a large sample of Galactic globular clusters and revolutionized our understanding of their stellar populations. In this paper, we expand previous studies by focusing our attention on the stellar clusters' internal kinematics. We computed proper motions for stars in 56 globular and one open clusters by combining the GO-13297 images with archival $\\textit{HST}$ data. The astro-photometric catalogs released with this paper represent the most complete and homogeneous collection of proper motions of stars in the cores of stellar clusters to date, and expand the information provided by the current (and future) $\\textit{Gaia}$ data releases to much fainter stars and into the crowded central regions. We also census the general kinematic properties of stellar clusters by computing the velocity-dispersion and anisotropy radial profiles of their bright members. We study the dependence on concentration and relaxation time, and derive dynamical distances. Finally, we present an in-depth kinematic analysis of the globular cluster NGC 5904.","source":"arXiv","year":2022,"language":"en","subjects":["astro-ph.GA","astro-ph.SR"],"doi":"10.3847/1538-4357/ac7727","url":"https://arxiv.org/abs/2206.09924","pdf_url":"https://arxiv.org/pdf/2206.09924","is_open_access":true,"published_at":"2022-06-20T18:00:00Z","score":66},{"id":"arxiv_2111.00635","title":"A SysTematic seaRch fOr Dual Agns in meRgINg Galaxies (ASTRO-DARING) II: first results from long-slit spectroscopic observations","authors":[{"name":"Yang-wei Zhang"},{"name":"Yang Huang"},{"name":"Jin-ming Bai"},{"name":"Xiao-wei Liu"},{"name":"Jian-guo Wang"},{"name":"Xiao-bo Dong"}],"abstract":"Building a large sample of kiloparsec (kpc)-scale dual active galactic nuclei (AGNs) amongst merging galaxies is of vital importance to understand the co-evolution between host galaxies and their central super massive black holes (SMBHs). Doing so, with just such a sample, we have developed an innovative method of systematically searching and identifying dual AGNs of amongst kpc scale merging galaxies and selected 222 candidates at redshifts $\\leqslant$ 0.25. All the selected candidates have FIRST radio detection and at least one of two cores previously revealed as AGN spectroscopically. We report the first results from A SysTematic seaRch fOr Dual Agns in meRgINg Galaxies (ASTRO-DARING), which consist of spatially resolved long-slit spectroscopic observations of 41 targets selected from our merging galaxies sample carried out between November 2014 and February 2017, using the Yunnan Faint Object Spectrograph and Camera (YFOSC) mounted on the 2.4 meter telescope in Lijiang of Yunnan Observatories. Of these 16 are likely dual AGNs and 15 are newly identified. The efficiency of ASTRO-DARING is thus nearly 40 per cent. With this method, we plan to build the first even sample of more than 50 dual AGNs constructed using a consistent approach. Further analysis of the dual AGN sample shall provide vital clues for understanding the co-evolution of galaxies and SMBHs.","source":"arXiv","year":2021,"language":"en","subjects":["astro-ph.GA"],"doi":"10.3847/1538-3881/ac2deb","url":"https://arxiv.org/abs/2111.00635","pdf_url":"https://arxiv.org/pdf/2111.00635","is_open_access":true,"published_at":"2021-11-01T00:28:42Z","score":65},{"id":"arxiv_2001.10527","title":"A New Lecture-Tutorial for Teaching Interferometry to Astro 101 Students","authors":[{"name":"Colin S. Wallace"},{"name":"Chase Hatcher"},{"name":"Timothy G. Chambers"},{"name":"Seth D. Hornstein"},{"name":"Julia Kamenetzky"},{"name":"Edward E. Prather"}],"abstract":"The ground-breaking image of a black hole's event horizon, which captured the public's attention and imagination in April 2019, was captured using the power of interferometry: many separate telescopes working together to observe the cosmos in incredible detail. Many recent astrophysical discoveries that have revolutionized the scientific community's understanding of the cosmos were made by interferometers such as LIGO, ALMA, and the Event Horizon Telescope. Astro 101 instructors who want their students to learn the science behind these discoveries must teach about interferometry. Decades of research show that using active learning strategies can significantly increase students' learning and reduces achievement gaps between different demographic groups over what is achieved from traditional lecture-based instruction. As part of an effort to create active learning materials on interferometry, we developed and tested a new Lecture-Tutorial to help Astro 101 students learn about key properties of astronomical interferometers. This paper describes this new Lecture-Tutorial and presents evidence for its effectiveness from a study conducted with 266 Astro 101 students at the University of North Carolina at Chapel Hill.","source":"arXiv","year":2020,"language":"en","subjects":["physics.ed-ph","astro-ph.GA"],"doi":"10.1119/10.0006124","url":"https://arxiv.org/abs/2001.10527","pdf_url":"https://arxiv.org/pdf/2001.10527","is_open_access":true,"published_at":"2020-01-28T18:58:48Z","score":64},{"id":"arxiv_1912.03137","title":"Photo-processing of astro-PAHs","authors":[{"name":"Christine Joblin"},{"name":"Gabi Wenzel"},{"name":"Sarah Rodriguez Castillo"},{"name":"Aude Simon"},{"name":"Hassan Sabbah"},{"name":"Anthony Bonnamy"},{"name":"Dominique Toublanc"},{"name":"Giacomo Mulas"},{"name":"Mingchao Ji"},{"name":"Alexandre Giuliani"},{"name":"Laurent Nahon"}],"abstract":"Polycyclic aromatic hydrocarbons (PAHs) are key species in astrophysical environments in which vacuum ultraviolet (VUV) photons are present, such as star-forming regions. The interaction with these VUV photons governs the physical and chemical evolution of PAHs. Models show that only large species can survive. However, the actual molecular properties of large PAHs are poorly characterized and the ones included in models are only an extrapolation of the properties of small and medium-sized species. We discuss here experiments performed on trapped ions including some at the SOLEIL VUV beam line DESIRS. We focus on the case of the large dicoronylene cation, C48H20+ , and compare its behavior under VUV processing with that of smaller species. We suggest that C2H2 is not a relevant channel in the fragmentation of large PAHs. Ionization is found to largely dominate fragmentation. In addition, we report evidence for a hydrogen dissociation channel through excited electronic states. Although this channel is minor, it is already effective below 13.6 eV and can significantly influence the stability of astro-PAHs. We emphasize that the competition between ionization and dissociation in large PAHs should be further evaluated for their use in astrophysical models.","source":"arXiv","year":2019,"language":"en","subjects":["astro-ph.GA","physics.chem-ph"],"doi":"10.1088/1742-6596/1412/6/062002","url":"https://arxiv.org/abs/1912.03137","pdf_url":"https://arxiv.org/pdf/1912.03137","is_open_access":true,"published_at":"2019-12-06T14:16:26Z","score":63},{"id":"arxiv_1911.06925","title":"Spatially-Resolved Spectroscopic Properties of Low-Redshift Star-Forming Galaxies","authors":[{"name":"Sebastian F. Sanchez"}],"abstract":"I review here the spatially-resolved spectroscopic properties of low-redshift star-forming galaxies (and their retired counter-parts), using results from the most recent Integral Field Spectroscopy galaxy surveys. First, I briefly summarise the global spectroscopic properties of these galaxies, discussing the main ionization processes, and the global relations described between the star-formation rates, oxygen abundances, and average properties of their stellar populations (age and metallicity) with the stellar mass. Second, I present the local distribution of the ionizing processes, down to kiloparsec scales, and I show how the global scaling relations found between integrated parameters (like the star-formation main sequence, mass-metallicity relation and Schmidt-Kennicutt law) present local/resolved counter-parts, with the global ones being just integrated/average versions of the local ones. I discuss the local/resolved star-formation and chemical enrichment histories and their implication on the inside-out growth of galaxies. Third, I present the radial distributions of the surface densities of the properties explored globally, and how they depend on the integrated galaxy properties. Finally, I summarise all these results and discuss what we have learned from them regarding the evolution of galaxies. Final version in Journal Page: https://www.annualreviews.org/doi/pdf/10.1146/annurev-astro-012120-013326","source":"arXiv","year":2019,"language":"en","subjects":["astro-ph.GA"],"doi":"10.1146/annurev-astro-012120-013326","url":"https://arxiv.org/abs/1911.06925","pdf_url":"https://arxiv.org/pdf/1911.06925","is_open_access":true,"published_at":"2019-11-16T00:51:21Z","score":63},{"id":"arxiv_1809.04300","title":"The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters - XVII. Public Catalogue Release","authors":[{"name":"D. Nardiello"},{"name":"M. Libralato"},{"name":"G. Piotto"},{"name":"J. Anderson"},{"name":"A. Bellini"},{"name":"A. Aparicio"},{"name":"L. R. Bedin"},{"name":"S. Cassisi"},{"name":"V. Granata"},{"name":"I. R. King"},{"name":"F. Lucertini"},{"name":"A. F. Marino"},{"name":"A. P. Milone"},{"name":"S. Ortolani"},{"name":"I. Platais"},{"name":"R. P. van der Marel"}],"abstract":"In this paper we present the astro-photometric catalogues of 56 globular clusters and one open cluster. Astrometry and photometry are mainly based on images collected within the \"HST Legacy Survey of Galactic Globular Clusters: Shedding UV Light on Their Populations and Formation\" (GO-13297, PI:~Piotto), and the \"ACS Survey of Galactic Globular Clusters\" (GO-10775, PI:~Sarajedini). For each source in the catalogues for which we have reliable proper motion we also publish a membership probability for separation of field and cluster stars. These new catalogues, which we make public in Mikulski Archive for Space Telescopes, replace previous catalogues by Paper VIII of this series.","source":"arXiv","year":2018,"language":"en","subjects":["astro-ph.SR","astro-ph.GA","astro-ph.IM"],"doi":"10.1093/mnras/sty2515","url":"https://arxiv.org/abs/1809.04300","pdf_url":"https://arxiv.org/pdf/1809.04300","is_open_access":true,"published_at":"2018-09-12T08:14:57Z","score":62},{"id":"arxiv_1704.07425","title":"The State-of-the-Art HST Astro-Photometric Analysis of the core of $ω$ Centauri. I. The Catalog","authors":[{"name":"A. Bellini"},{"name":"J. Anderson"},{"name":"L. R. Bedin"},{"name":"I. R. King"},{"name":"R. P. van der Marel"},{"name":"G. Piotto"},{"name":"A. M. Cool"}],"abstract":"We have constructed the most-comprehensive catalog of photometry and proper motions ever assembled for a globular cluster (GC). The core of $ω$Cen has been imaged over 650 times through WFC3's UVIS and IR channels for the purpose of detector calibration. There exist from 4 to over 60 exposures through each of 26 filters, stretching continuously from F225W in the UV to F160W in the infrared. Furthermore, the 11-year baseline between these data and a 2002 ACS survey has allowed us to more than double the proper-motion accuracy and triple the number of well-measured stars compared to our previous groundbreaking effort. This totally unprecedented complete spectral coverage for over 470,000 stars within the cluster's core, from the tip of the red-giant branch down to the white dwarfs, provides the best astro-photometric observational data base yet to understand the multiple-population phenomenon in any GC. In this first paper of the series we describe in detail the data-reduction processes and deliver the astro-photometric catalog to the astronomical community.","source":"arXiv","year":2017,"language":"en","subjects":["astro-ph.SR","astro-ph.GA","astro-ph.IM"],"doi":"10.3847/1538-4357/aa7059","url":"https://arxiv.org/abs/1704.07425","pdf_url":"https://arxiv.org/pdf/1704.07425","is_open_access":true,"published_at":"2017-04-24T19:25:30Z","score":61},{"id":"arxiv_1705.01951","title":"The State-of-the-Art HST Astro-Photometric Analysis of the core of $ω$ Centauri. II. Differential-Reddening Map","authors":[{"name":"A. Bellini"},{"name":"J. Anderson"},{"name":"R. P. van der Marel"},{"name":"I. R. King"},{"name":"G. Piotto"},{"name":"L. R. Bedin"}],"abstract":"We take advantage of the exquisite quality of the Hubble Space Telescope astro-photometric catalog of the core of wCen presented in the first paper of this series to derive a high-resolution, high-precision, high-accuracy differential-reddening map of the field. The map has a spatial resolution of 2x2 square arcsecs over a total field of view of about 4.3'x4.3'. The differential reddening itself is estimated via an iterative procedure using five distinct color-magnitude diagrams, which provided consistent results to within the 0.1% level. Assuming an average reddening value E(B-V)=0.12, the differential-reddening within the cluster's core can vary by up to +/- 10%, with a typical a standard deviation of about 4%. Our differential-reddening map is made available to the astronomical community in the form of a multi-extension FITS file. This differential-reddening map is essential for a detailed understanding of the multiple stellar populations of wCen, as presented in the next paper in this series. Moreover, it provides unique insight into the level of small spatial-scale extinction variations in the Galactic foreground.","source":"arXiv","year":2017,"language":"en","subjects":["astro-ph.SR","astro-ph.GA","astro-ph.IM"],"doi":"10.3847/1538-4357/aa705f","url":"https://arxiv.org/abs/1705.01951","pdf_url":"https://arxiv.org/pdf/1705.01951","is_open_access":true,"published_at":"2017-05-04T18:00:06Z","score":61},{"id":"arxiv_1706.07063","title":"The State-of-the-Art HST Astro-Photometric Analysis of the core of ωCentauri. III. The Main Sequence's Multiple Populations Galore","authors":[{"name":"A. Bellini"},{"name":"A. P. Milone"},{"name":"J. Anderson"},{"name":"A. F. Marino"},{"name":"G. Piotto"},{"name":"R. P. van der Marel"},{"name":"L. R. Bedin"},{"name":"I. R. King"}],"abstract":"We take advantage of the exquisite quality of the Hubble Space Telescope 26-filter astro-photometric catalog of the core of Omega Cen presented in the first paper of this series and the empirical differential-reddening correction presented in the second paper in order to distill the main sequence into its constituent populations. To this end, we restrict ourselves to the five most useful filters: the magic \"trio\" of F275W, F336W, and F438W, along with F606W and F814W. We develop a strategy for identifying color systems where different populations stand out most distinctly, then we isolate those populations and examine them in other filters where their sub-populations also come to light. In this way, we have identified at least 15 sub-populations, each of which has a distinctive fiducial curve through our 5-dimensional photometric space. We confirm the MSa to be split into two subcomponents, and find that both the bMS and the rMS are split into three subcomponents. Moreover, we have discovered two additional MS groups: the MSd (which has three subcomponents) shares similar properties with the bMS, and the MSe (which has four subcomponents), has properties more similar to those of the rMS. We examine the fiducial curves together and use synthetic spectra to infer relative heavy-element, light-element, and Helium abundances for the populations. Our findings show that the stellar populations and star formation history of Omega Cen are even more complex than inferred previously. Finally, we provide as a supplement to the original catalog a list that identifies for each star which population it most likely is associated with.","source":"arXiv","year":2017,"language":"en","subjects":["astro-ph.SR","astro-ph.GA"],"doi":"10.3847/1538-4357/aa7b7e","url":"https://arxiv.org/abs/1706.07063","pdf_url":"https://arxiv.org/pdf/1706.07063","is_open_access":true,"published_at":"2017-06-21T18:00:25Z","score":61},{"id":"crossref_10.1016/s0167-8140(15)40325-1","title":"SP-0327: ASTRO accreditation programmes (APEx)-ASTRO","authors":[{"name":"P. Tripuraneni"}],"abstract":"","source":"CrossRef","year":2015,"language":"en","subjects":null,"doi":"10.1016/s0167-8140(15)40325-1","url":"https://doi.org/10.1016/s0167-8140(15)40325-1","is_open_access":true,"citations":1,"published_at":"","score":59.03},{"id":"arxiv_1508.04426","title":"Simulating Astro-H Observations of Sloshing Gas Motions in the Cores of Galaxy Clusters","authors":[{"name":"J. ZuHone"},{"name":"E. Miller"},{"name":"A. Simionescu"},{"name":"M. Bautz"}],"abstract":"Astro-H will be the first X-ray observatory to employ a high-resolution microcalorimeter, capable of measuring the shift and width of individual spectral lines to the precision necessary for estimating the velocity of the diffuse plasma in galaxy clusters. This new capability is expected to bring significant progress in understanding the dynamics, and therefore the physics, of the intracluster medium. However, because this plasma is optically thin, projection effects will be an important complicating factor in interpreting future Astro-H measurements. To study these effects in detail, we performed an analysis of the velocity field from simulations of a galaxy cluster experiencing gas sloshing, and generated synthetic X-ray spectra, convolved with model Astro-H Soft X-ray Spectrometer (SXS) responses. We find that the sloshing motions produce velocity signatures that will be observable by Astro-H in nearby clusters: the shifting of the line centroid produced by the fast-moving cold gas underneath the front surface, and line broadening produced by the smooth variation of this motion along the line of sight. The line shapes arising from inviscid or strongly viscous simulations are very similar, indicating that placing constraints on the gas viscosity from these measurements will be difficult. Our spectroscopic analysis demonstrates that, for adequate exposures, Astro-H will be able to recover the first two moments of the velocity distribution of these motions accurately, and in some cases multiple velocity components may be discerned. The simulations also confirm the importance of accurate treatment of PSF scattering in the interpretation of Astro-H/SXS spectra of cluster plasmas.","source":"arXiv","year":2015,"language":"en","subjects":["astro-ph.HE","astro-ph.GA"],"doi":"10.3847/0004-637X/821/1/6","url":"https://arxiv.org/abs/1508.04426","pdf_url":"https://arxiv.org/pdf/1508.04426","is_open_access":true,"published_at":"2015-08-18T15:40:09Z","score":59},{"id":"crossref_10.1093/ofid/ofv133.1240","title":"Development of Anemia and Changes in Hemoglobin Concentrations With Amphotericin B Therapy for Cryptococcal Meningitis","authors":[{"name":"Lillian Tugume"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Bozena Morawski"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Mahsa Abassi"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Nathan Bahr"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Reuben Kiggundu"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Henry Nabeta"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Kathy Huppler Hullsiek"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Taseera Kabanda"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Abdu Musubire"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Charlotte Schutz"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Conrad Muzoora"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Darlisha Williams"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Melissa Rolfes"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Graeme Meintjes"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"Joshua Rhein"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"David Meya"},{"name":"COAT Trial and ASTRO-CM Trial Teams"},{"name":"David Boulware"},{"name":"COAT Trial and ASTRO-CM Trial Teams"}],"abstract":"","source":"CrossRef","year":2015,"language":"en","subjects":null,"doi":"10.1093/ofid/ofv133.1240","url":"https://doi.org/10.1093/ofid/ofv133.1240","is_open_access":true,"published_at":"","score":59},{"id":"crossref_10.1093/ofid/ofv133.507","title":"Enhanced Consolidation Therapy With High-Dose Fluconazole and Sertraline Ameliorates Negative Outcomes Associated With Persistent Cerebrospinal Fluid Culture Positivity in Cryptococcal Meningitis","authors":[{"name":"Mahsa Abassi"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Joshua Rhein"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Bozena Morawski"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Kathy H. Hullsiek"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Lillian Tugume"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Henry Nabeta"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Reuben Kiggundu"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Andrew Akampurira"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"Darlisha Williams"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"David Meya"},{"name":"on behalf of the ASTRO-CM Trial Team"},{"name":"David Boulware"},{"name":"on behalf of the ASTRO-CM Trial Team"}],"abstract":"","source":"CrossRef","year":2015,"language":"en","subjects":null,"doi":"10.1093/ofid/ofv133.507","url":"https://doi.org/10.1093/ofid/ofv133.507","is_open_access":true,"published_at":"","score":59}],"total":342391,"page":1,"page_size":20,"sources":["arXiv","CrossRef"],"query":"astro-ph.GA"}