Advanced

Blue straggler production in globular clusters

Davies, Melvyn B LU ; Piotto, Giampaolo and de Angeli, Francesca (2004) In Monthly Notices of the Royal Astronomical Society 349(1). p.129-134
Abstract
Recent Hubble Space Telescope observations of a large sample of globular clusters reveal that every cluster contains between 40 and 400 blue stragglers.The population does not correlate with either stellar collision rate (as would be expected if all blue stragglers were formed via collisions) or total mass (as would be expected if all blue stragglers were formed via the unhindered evolution of a subset of the stellar population). In this paper, we support the idea that blue stragglers are made through both channels. The number produced via collisions tends to increase with cluster mass. In this paper we show how the current population produced from primordial binaries decreases with increasing cluster mass;exchange encounters with third,... (More)
Recent Hubble Space Telescope observations of a large sample of globular clusters reveal that every cluster contains between 40 and 400 blue stragglers.The population does not correlate with either stellar collision rate (as would be expected if all blue stragglers were formed via collisions) or total mass (as would be expected if all blue stragglers were formed via the unhindered evolution of a subset of the stellar population). In this paper, we support the idea that blue stragglers are made through both channels. The number produced via collisions tends to increase with cluster mass. In this paper we show how the current population produced from primordial binaries decreases with increasing cluster mass;exchange encounters with third, single stars in the most massivec lusters tend to reduce the fraction of binaries containing a primary close to the current turn-off mass. Rather, their primaries tend to be somewhat more massive (~1-3 M<SUB>solar</SUB>) and have evolved off the main sequence, filling their Roche lobes in the past, often converting their secondaries into blue stragglers (but more than 1 Gyr or so ago and thus they are no longer visible as blue stragglers). We show that this decline in the primordial blue straggler population is likely to be offset by the increase in the number of blue stragglers produced via collisions. The predicted total blue straggler population is therefore relatively independent of cluster mass, thus matching the observed population. This result does not depend on any particular assumed blue straggler lifetime. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
blue stragglers, globular clusters: general
in
Monthly Notices of the Royal Astronomical Society
volume
349
issue
1
pages
129 - 134
publisher
Wiley-Blackwell
external identifiers
  • scopus:1842431671
ISSN
1365-2966
DOI
10.1111/j.1365-2966.2004.07474.x
language
English
LU publication?
yes
id
05a31657-7e20-4374-84d2-5e47e2da84a6 (old id 129616)
date added to LUP
2007-07-12 15:43:53
date last changed
2017-12-10 03:50:48
@article{05a31657-7e20-4374-84d2-5e47e2da84a6,
  abstract     = {Recent Hubble Space Telescope observations of a large sample of globular clusters reveal that every cluster contains between 40 and 400 blue stragglers.The population does not correlate with either stellar collision rate (as would be expected if all blue stragglers were formed via collisions) or total mass (as would be expected if all blue stragglers were formed via the unhindered evolution of a subset of the stellar population). In this paper, we support the idea that blue stragglers are made through both channels. The number produced via collisions tends to increase with cluster mass. In this paper we show how the current population produced from primordial binaries decreases with increasing cluster mass;exchange encounters with third, single stars in the most massivec lusters tend to reduce the fraction of binaries containing a primary close to the current turn-off mass. Rather, their primaries tend to be somewhat more massive (~1-3 M&lt;SUB&gt;solar&lt;/SUB&gt;) and have evolved off the main sequence, filling their Roche lobes in the past, often converting their secondaries into blue stragglers (but more than 1 Gyr or so ago and thus they are no longer visible as blue stragglers). We show that this decline in the primordial blue straggler population is likely to be offset by the increase in the number of blue stragglers produced via collisions. The predicted total blue straggler population is therefore relatively independent of cluster mass, thus matching the observed population. This result does not depend on any particular assumed blue straggler lifetime.},
  author       = {Davies, Melvyn B and Piotto, Giampaolo and de Angeli, Francesca},
  issn         = {1365-2966},
  keyword      = {blue stragglers,globular clusters: general},
  language     = {eng},
  number       = {1},
  pages        = {129--134},
  publisher    = {Wiley-Blackwell},
  series       = {Monthly Notices of the Royal Astronomical Society},
  title        = {Blue straggler production in globular clusters},
  url          = {http://dx.doi.org/10.1111/j.1365-2966.2004.07474.x},
  volume       = {349},
  year         = {2004},
}