Related papers: A Binary Origin for Blue Stragglers in Globular Cl…
We present preliminary results obtained from the comparison of the specific frequencies of Blue Straggler Stars (BSS) detected so far in a sample of 26 Galactic globular clusters. The number of BSS seems to increase almost linearly with…
We have analyzed populations of blue straggler stars (BSSs) in 24 Magellanic Cloud star clusters using multi-passband Hubble Space Telescope images. We compiled a homogeneous BSS database, containing both traditional and evolved BSSs. We…
Globular star clusters that formed at the same cosmic time may have evolved rather differently from a dynamical point of view (because that evolution depends on the internal environment) through a variety of processes that tend…
Bifurcated patterns of blue straggler stars in their color--magnitude diagrams have atracted significant attention. This type of special (but rare) pattern of two distinct blue straggler sequences is commonly interpreted as evidence of…
The importance of stellar encounters in producing stellar exotica in dense stellar clusters is reviewed. We discuss how collisions between main-sequence stars may be responsible for the production of blue stragglers in globular clusters. We…
Blue straggler stars (BSS) are abundantly observed in all Galactic globular clusters (GGC) where data exist. However, observations alone cannot reveal the relative importance of various formation channels or the typical formation times for…
In this chapter we consider two formation channels for blue straggler stars: 1) the merger of two single stars via a collision, and 2) those produced via mass transfer within a binary. We review how computer simulations show that stellar…
Although the formation of blue straggler stars (BSSs) is routinely attributed to stellar interactions in binary systems, the relative importance of the direct collision and slow(er) stellar coalescence formation channels is still poorly…
In this chapter we review the various suggested channels for the formation and evolution of blue straggler stars (BSSs) in different environments and their observational predictions. These include mass transfer during binary stellar…
Combination of high-precision photometry and spectroscopy allows the detailed study of the upper main sequence in open clusters. We are carrying out a comprehensive study of a number of clusters containing Be stars in order to evaluate the…
We investigate the structure and evolution of blue stragglers stars which were formed from direct stellar collisions between main sequence stars in globular clusters. In particular, we look at the rotational evolution of the products of…
Among the most striking feature of blue straggler stars (BSS) is the presence of multiple sequences of BSSs in the colour-magnitude diagrams (CMDs) of several globular clusters. It is often envisaged that such a multiple BSS sequence would…
The formation of massive stars is one of the major unsolved problems in stellar astrophysics. However, only few if any of these are found as single stars, on average massive stars have more than one companion. Many of them are born in dense…
Building on the recent release of a new \emph{Gaia}-based blue straggler star catalog in Galactic open star clusters (OCs), we explored the properties of these stars in a cluster sample spanning a wide range in fundamental parameters. We…
This chapter describes the current state of models of individual blue stragglers. Stellar collisions, binary mergers (or coalescence), and partial or ongoing mass transfer have all been studied in some detail. The products of stellar…
In open star clusters, where all members formed at about the same time, blue straggler stars are typically observed to be brighter and bluer than hydrogen-burning main-sequence stars, and therefore should already have evolved into giant…
Galactic globular clusters are old, dense star systems typically containing 10\super{4}--10\super{7} stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars,…
Improved observations of globular clusters are uncovering a large number of radio pulsars and of X-ray sources. The latter include binaries in which a neutron star or a white dwarf accretes matter from a companion, recycled pulsars, and…
In this paper, we systematically studied blue stragglers produced from primordial binary evolution via a binary population synthesis approach, and examined their contribution to the integrated spectral energy distributions of the host…
For a sample of 38 Galactic globular clusters (GCs), we confront the observed distributions of blue straggler (BS) proper motions and masses (derived from isochrone fitting) from the BS catalog of Simunovic & Puzia with theoretical…