The radial distribution of blue straggler stars and the nature of their progenitors

Abstract

The origin of blue straggler stars (BSS) in globular clusters (GCs) is still not fully understood: they can form from stellar collisions, or through mass transfer in isolated, primordial binaries (PBs). In this paper we use the radial distribution of BSS observed in four GCs (M3, 47Tuc, NGC6752 and omega Cen) to investigate which formation process prevails. We find that both channels co-exist in all the considered GCs. The fraction of mass-transfer (collisional) BSS with respect to the total number of BSS is around ~0.4-0.5 (~0.5-0.6) in M3, 47Tuc, and NGC6752. The case of omega Cen is peculiar with an underproduction of collisional BSS. The relative lack of collisional BSS in omega Cen can be understood if mass segregation has not yet driven to the core a sizeable number of PBs, which dominate stellar collisions through three- and four-body processes. The spatial distribution of BSS provides strong hints to their origin: the BSS in the cluster outskirts form almost exclusively from mass transfer in PBs, whereas the BSS found close to the cluster core most likely have a collisional origin.

9 pages, 5 figures, MNRAS, in press, matches the published version

References in corpus (1)

• Discovery of Carbon/Oxygen depleted Blue Straggler Stars in 47 Tucanae: the chemical signature of a mass-transfer formation process

Cited by in corpus (38)

• Dynamical age differences among coeval star clusters as revealed by blue stragglers
• A Binary Origin for Blue Stragglers in Globular Clusters
• Another Non-segregated Blue Straggler Population in a Globular Cluster: the Case of NGC 2419
• Investigating mass segregation process in globular clusters with Blue Straggler Stars: the impact of dark remnants
• Blue Straggler Stars in the Unusual Globular Cluster NGC 6388
• A Panchromatic Study of the Globular Cluster NGC 1904. I: The Blue Straggler Population
• A new, Gaia based, catalogue of blue straggler stars in open clusters
• The Blue Straggler Population of the Globular Cluster M5
• A Correlation between Blue Straggler and Binary Fractions in the core of Galactic Globular Clusters
• Formation of black holes in the pair-instability mass gap: evolution of a post-collision star
• Blue straggler stars in dwarf spheroidal galaxies
• The surprising external upturn of the Blue Straggler radial distribution in M55
• Blue Straggler Populations of Seven Open Clusters with Gaia DR2
• A kinematic view of NGC 1261: structural parameters, internal dispersion, absolute proper motion and Blue Straggler Stars
• The "dynamical clock": dating the internal dynamical evolution of star clusters with Blue Straggler Stars
• Oscillating Blue Stragglers, gamma Doradus stars and eclipsing binaries in the open cluster NGC2506
• Dynamical friction in multi-component evolving globular clusters
• Spectral Energy Distribution of Blue Stragglers in the core of 47 Tucanae
• Mass segregation in the outer halo globular cluster Palomar 14
• From hydrodynamics to N-body simulations of star clusters: mergers and rotation
• Spinning like a Blue Straggler: the population of fast rotating Blue Straggler stars in Omega Centauri
• Probing the role of dynamical friction in shaping the BSS radial distribution. I - Semi-analytical models and preliminary N-body simulations
• The Blue Straggler population in the globular cluster M53 (NGC5024): a combined HST, LBT, CFHT study
• Formation and Evolution of Blue Stragglers in 47 Tucanae
• A study of the blue straggler population of the old open cluster Collinder 261
• UV-Bright Stellar Populations and Their Evolutionary Implications in the Collapsed-Core Cluster M15
• The Rich Lack Close Neighbours: The Dependence of Blue-Straggler Fraction on Metallicity
• Investigation of the Globular Cluster NGC 2808 with the Ultra-Violet Imaging Telescope
• Blue Straggler Stars in Globular Clusters: a powerful tool to probe the internal dynamical evolution of stellar systems
• A possible solution to the Milky Way's binary-deficient retrograde stellar population. Evidence that $\omega$ Centauri has formed in an extreme starburst
• The Blue Straggler Population in Dwarf Galaxies
• Tidal Interactions of Red Giants with Environment Stars in Globular Clusters
• Blue Stragglers in Globular Clusters: Observations, Statistics and Physics
• The Solar Neighborhood LII: M Dwarf Twin Binaries -- Presumed Identical Twins Appear Fraternal in Variability, Rotation, H$\alpha$, and X-rays
• Rubin Data Preview 1: Extending the View of Unresolved Binary Stars in 47 Tucanae
• Effects of stellar collisions on star cluster evolution and core collapse
• Using Binaries in Globular Clusters to Catch Sight of Intermediate-Mass Black Holes
• Taking apart the dynamical clock. Fat-tailed dynamical kicks shape the blue-straggler star bimodality