Globular cluster ≈ Globular cluster
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<i>Gaia</i> Data Release 2 Open
Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry and photometry are unprecedented. Aims. …
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Multiple Stellar Populations in Globular Clusters Open
Globular clusters (GCs) exhibit star-to-star variations in specific elements (e.g., He, C, N, O, Na, Al) that bear the hallmark of high-temperature H-burning. These abundance variations can be observed spectroscopically and also photometri…
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Binary black hole mergers from globular clusters: Masses, merger rates, and the impact of stellar evolution Open
The recent discovery of GW150914, the binary black hole merger detected by Advanced LIGO, has the potential to revolutionize observational astrophysics. But to fully utilize this new window into the universe, we must compare these new obse…
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Re-evaluating old stellar populations Open
Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Her…
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A catalogue of masses, structural parameters, and velocity dispersion profiles of 112 Milky Way globular clusters Open
We have determined masses, stellar mass functions and structural parameters\nof 112 Milky Way globular clusters by fitting a large set of N-body simulations\nto their velocity dispersion and surface density profiles. The velocity\ndispersi…
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Evidence for two early accretion events that built the Milky Way stellar halo Open
The Gaia Sausage is the major accretion event that built the stellar halo of the Milky Way galaxy. Here, we provide dynamical and chemical evidence for a second substantial accretion episode, distinct from the Gaia Sausage. The Sequoia Eve…
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The<i>Hubble Space Telescope</i>UV Legacy Survey of Galactic globular clusters – IX. The Atlas of multiple stellar populations Open
We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the 'Hubble Space Telescope (HST ) UV Legacy Survey of Galactic GCs', to identify and characterize their multiple stellar …
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Gaia EDR3 view on galactic globular clusters Open
We use the data from Gaia Early Data Release 3 (EDR3) to study the kinematic properties of Milky Way globular clusters. We measure the mean parallaxes and proper motions (PM) for 170 clusters, determine the PM dispersion profiles for more …
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Mean proper motions, space orbits, and velocity dispersion profiles of Galactic globular clusters derived from<i>Gaia</i>DR2 data Open
We have derived the mean proper motions and space velocities of 154 Galactic\nglobular clusters and the velocity dispersion profiles of 141 globular clusters\nbased on a combination of Gaia DR2 proper motions with ground-based\nline-of-sig…
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Hot Subluminous Stars Open
Hot subluminous stars of spectral type B and O are core helium-burning stars\nat the blue end of the horizontal branch or have evolved even beyond that\nstage. Strikingly, the distribution in the Hertzsprung-Russell diagram of\nHe-rich vs.…
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The O-Na And Mg-Al Anticorrelations In Turn-Off And Early Subgiants In Globular Clusters Open
High dispersion spectra (R greater than or similar to 40 000) for a quite large number of stars at the main sequence turn-off and at the base of the giant branch in NGC 6397 and NGC 6752 were obtained with the UVES on Kueyen (VLT UT2). The…
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The formation and assembly history of the Milky Way revealed by its globular cluster population Open
We use the age–metallicity distribution of 96 Galactic globular clusters (GCs) to infer the formation and assembly history of the Milky Way (MW), culminating in the reconstruction of its merger tree. Based on a quantitative comparison of t…
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MOCCA-SURVEY Database – I. Coalescing binary black holes originating from globular clusters Open
In this first of a series of papers, we utilize results for around 2000 star cluster models simulated using the mocca code for star cluster evolution (Survey Database I) to determine the astrophysical properties and local merger rate densi…
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Accurate distances to Galactic globular clusters through a combination of <i>Gaia</i> EDR3, <i>HST</i>, and literature data Open
We have derived accurate distances to Galactic globular clusters by combining data from the Gaia Early Data Release 3 (EDR3) with distances based on Hubble Space Telescope (HST) data and literature-based distances. We determine distances e…
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The total mass of the Large Magellanic Cloud from its perturbation on the Orphan stream Open
In a companion paper by Koposov et al., RR Lyrae from Gaia Data Release 2 are used to demonstrate that stars in the Orphan stream have velocity vectors significantly misaligned with the stream track, suggesting that it has received a large…
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Eccentric black hole mergers forming in globular clusters Open
We derive the probability for a newly formed binary black hole (BBH) to\nundergo an eccentric gravitational wave (GW) merger during binary-single\ninteractions inside a stellar cluster. By integrating over the hardening\ninteractions such …
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Post-Newtonian Dynamics in Dense Star Clusters: Highly Eccentric, Highly Spinning, and Repeated Binary Black Hole Mergers Open
We present models of realistic globular clusters with post-Newtonian dynamics for black holes. By modeling the relativistic accelerations and gravitational-wave emission in isolated binaries and during three- and four-body encounters, we f…
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Black holes: The next generation—repeated mergers in dense star clusters and their gravitational-wave properties Open
When two black holes merge in a dense star cluster, they form a new black\nhole with a well-defined mass and spin. If that "second-generation" black hole\nremains in the cluster, it will continue to participate in dynamical\nencounters, fo…
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Gaia Data Release 2. Observational Hertzsprung-Russell diagrams Open
[Abstract] Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, and homogeneity of both astrometry and photometry are unpreceden…
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Merging black hole binaries: the effects of progenitor's metallicity, mass-loss rate and Eddington factor Open
The first four gravitational wave events detected by LIGO were all\ninterpreted as merging black hole binaries (BHBs), opening a new perspective on\nthe study of such systems. Here we use our new population-synthesis code MOBSE,\nan upgrad…
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The ACS Survey Of Galactic Globular Clusters. VII. Relative Ages Open
The ACS Survey of Galactic globular clusters is a Hubble Space Telescope Treasury program designed to provide a new large, deep, and homogeneous photometric database. Based on observations from this program, we have measured precise relati…
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Proper motions and dynamics of the Milky Way globular cluster system from<i>Gaia</i>DR2 Open
We use Gaia Data Release 2 to determine the mean proper motions for 150 Milky\nWay globular clusters (almost the entire known population), with a typical\nuncertainty of 0.05 mas/yr limited mainly by systematic errors. Combining them\nwith…
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Improving the open cluster census Open
Context. Data from the Gaia satellite are revolutionising our understanding of the Milky Way. With every new data release, there is a need to update the census of open clusters. Aims. We aim to conduct a blind, all-sky search for open clus…
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The dragon simulations: globular cluster evolution with a million stars Open
Introducing the dragon simulation project, we present direct N-body simulations of four massive globular clusters (GCs) with 106 stars and 5 per cent primordial binaries at a high level of accuracy and realism. The GC evolution is computed…
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DYNAMICAL FORMATION OF THE GW150914 BINARY BLACK HOLE Open
We explore the possibility that GW150914, the binary black hole (BBH) merger recently detected by Advanced LIGO, was formed by gravitational interactions in the core of a dense star cluster. Using models of globular clusters (GCs) with det…
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The Abundances Of Neutron-Capture Species In The Very Metal-Poor Globular Cluster M15: A Uniform Analysis Of Red Giant Branch And Red Horizontal Branch Stars Open
The globular cluster M15 is unique in its display of star-to-star variations in the neutron-capture elements. Comprehensive abundance surveys have been previously conducted for handfuls of M15 red giant branch (RGB) and red horizontal bran…
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Properties of globular cluster systems in nearby early-type galaxies Open
We present a study of globular clusters (GCs) in 17 relatively nearby early-type galaxies, based on deep F555W and F814W images from the Wide Field Planetary Camera 2, on board the Hubble Space Telescope. A detailed analysis of color distr…
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Constraining the mass and radius of neutron stars in globular clusters Open
In this paper, we analyse observations of eight quiescent low-mass X-ray binaries in globular clusters and combine them to determine the neutron star mass–radius curve and the equation of state of dense matter. We determine the effect that…
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The feeble giant. Discovery of a large and diffuse Milky Way dwarf galaxy in the constellation of Crater Open
© 2016 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.We announce the discovery of the Crater 2 dwarf galaxy, identified in imaging data of the VLT Survey Telescope ATLAS survey. Given its half…
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The influence of Sagittarius and the Large Magellanic Cloud on the stellar disc of the Milky Way Galaxy Open
We present N-body simulations of a Sagittarius-like dwarf spheroidal galaxy (Sgr) that follow its orbit about the Milky Way (MW) since its first crossing of the Galaxy's virial radius to the present day. As Sgr orbits around the MW, it exc…