TheHubble Space TelescopeUV Legacy Survey of Galactic Globular Clusters. XV. The Dynamical Clock: Reading Cluster Dynamical Evolution from the Segregation Level of Blue Straggler Stars

  title={TheHubble Space TelescopeUV Legacy Survey of Galactic Globular Clusters. XV. The Dynamical Clock: Reading Cluster Dynamical Evolution from the Segregation Level of Blue Straggler Stars},
  author={Francesco R. Ferraro and Barbara Lanzoni and Silvia Raso and Domenico Nardiello and Emanuele Dalessandro and Enrico Vesperini and Giampaolo Piotto and Cristina Pallanca and Giacomo Beccari and Andrea Bellini and Mattia Libralato and Jay Barry Anderson and Antonio Aparicio and Luigi R. Bedin and Santi Cassisi and Antonino P. Milone and S. Ortolani and Alvio Renzini and Maurizio Salaris and Roeland P. van der Marel},
  journal={The Astrophysical Journal},
The parameter A+, defined as the area enclosed between the cumulative radial distribution of blue straggler stars (BSSs) and that of a reference population, is a powerful indicator of the level of BSS central segregation. As part of the Hubble Space Telescope UV Legacy Survey of Galactic globular clusters (GCs), here we present the BSS population and the determination of A+ in 27 GCs observed out to about one half-mass radius. In combination with 21 additional clusters discussed in a previous… 
The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XVIII. Proper-motion Kinematics of Multiple Stellar Populations in the Core Regions of NGC 6352
We present the analysis of the radial distributions and kinematic properties of the multiple stellar populations (mPOPs) hosted in the globular cluster (GC) NGC 6352 as part of the Hubble Space
Extra-tidal structures around the Gaia Sausage candidate globular cluster NGC 6779 (M56)
We present results on the stellar density radial profile of the outer regions of NGC6779, a Milky Way globular cluster recently proposed as a candidate member of the Gaia Sausage structure, a merger
Blue Straggler Stars beyond the Milky Way. IV. Radial Distributions and Dynamical Implications
Blue straggler stars have been proposeed as powerful indicators to measure the dynamical state of Galactic globular clusters. Here we examine for the first time if this framework of blue straggler
Star-density Profiles of Six Old Star Clusters in the Large Magellanic Cloud
We used resolved star counts from Hubble Space Telescope images to determine the center of gravity and the projected density profiles of 6 old globular clusters in the Large Magellanic Cloud (LMC),
High-resolution Extinction Map in the Direction of the Bulge Globular Cluster NGC 6440
We used optical images acquired with the UVIS channel of the Wide Field Camera 3 on board of the Hubble Space Telescope to construct the first high-resolution extinction map in the direction of NGC
Spectral Energy Distribution of Blue Stragglers in the Core of 47 Tucanae
We have constructed the Spectral Energy Distributions (SEDs) of a sample of Blue Straggler Stars (BSSs) in the core of the globular cluster 47 Tucanae, taking advantage of the large set of high
Dependence of the Old Star Clusters’ Dynamical Clock on the Host Galaxy Gravitational Field
  • A. Piatti
  • Physics
    Research Notes of the AAS
  • 2020
I report outcomes of the analysis of the $A^+$ parameter, which measures the level of radial segregation of blue straggler stars in old star clusters, commonly known as the dynamical clock for the
Investigating the Blue Straggler Stars radial distribution in globular clusters with Monte Carlo simulations
We investigate the evolution of the radial distribution of Blue Straggler Stars through a set of Monte Carlo simulations of star clusters under a variety of initial conditions. We used a novel
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Hubble Space Telescope proper motion (HSTPROMO) catalogs of Galactic globular clusters. IV. Kinematic profiles and average masses of blue straggler stars
We make use of the Hubble Space Telescope proper-motion catalogs derived by Bellini et al. (2014) to produce the first radial velocity-dispersion profiles sigma(R) for blue straggler stars (BSSs) in
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We have used the high-resolution Wide Field Planetary Camera (WFPC2) on the Hubble Space Telescope (HST) and wide-field ground-based observations to construct a catalog of blue straggler stars (BSSs)
Environmental effects on the globular cluster blue straggler population: a statistical approach
Context. Blue stragglers stars (BSS) constitute an ubiquitous population of objects whose origin involves both dynamical and stellar evolution. Aims. In this paper we study the properties of a
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We present a multiwavelength photometric analysis of the globular cluster M2. The data set has been obtained by combining high-resolution (Hubble Space Telescope/WFPC2 and ACS) and wide-field (Galaxy
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By combining high-resolution HST and wide-field ground-based observations, in ultraviolet and optical bands, we study the blue straggler star (BSS) population of the galactic globular cluster M5 (NGC
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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
The First Direct Measurement of the Mass of a Blue Straggler in the Core of a Globular Cluster: BSS 19 in 47 Tucanae
Hot, young blue straggler stars are observed by the Hubble Space Telescope to exist in the cores of very old globular clusters. Theory maintains that these stars must be more massive than