Related papers: On the triple origin of blue stragglers
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…
Blue stragglers are anomalously massive core hydrogen-burning stars that, according to the theory of single star evolution, should not exist. They are suspected to form in mass-enhancement processes, involving binary evolution or stellar…
Context. Blue Stragglers Stars (BSSs) are thought to form in globular clusters by two main formation channels: i) mergers induced by stellar collisions and ii) coalescence or mass-transfer between companions in binary systems. The detailed…
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…
Blue stragglers are thought to be formed from the merger or coalescence of two stars, but the details of their formation in clusters has been difficult to disentangle. We discuss the two main formation mechanisms for blue stragglers…
Blue stragglers in globular clusters are abnormally massive stars that should have evolved off the stellar main sequence long ago. There are two known processes that can create these objects: direct stellar collisions and binary evolution.…
Blue straggler stars (BSSs) are the most massive stars in a cluster formed via binary or higher-order stellar interactions. Though the exact nature of such formation scenarios is difficult to pin down, we provide observational constraints…
Blue stragglers (BSS) are stars whose position in the Color-Magnitude Diagram (CMD) places them above the main sequence turn-off (TO) point of a star cluster. Using data from the core of 47 Tuc in the ultraviolet (UV), we have identified…
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…
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…
By using the high resolution spectrograph FLAMES@VLT we performed the first systematic campaign devoted to measure chemical abundances of blue straggler stars (BSSs). These stars, whose existence is not predicted by the canonical stellar…
Blue stragglers are natural phenomena in star clusters. They originate through mass transfer in isolated binaries, as well as through encounters between two or more stars, in a complex interplay between stellar dynamics and stellar…
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…
Blue straggler stars (BSSs) are brighter and bluer than the main-sequence (MS) turnoff and more massive than MS stars.Two scenarios for their formation have been proposed: collision-induced stellar mergers (COL-BSSs),or mass-transfer in…
We examine the blue straggler star (BSS) populations of six old ($\geq$4 Gyr) open clusters: M67, NGC 188, NGC 6791, Berkeley 32, Berkeley 39, and Trumpler 19. We find that 50% of BSSs have color-magnitude diagram (CMD) locations…
Blue straggler stars (BSS) have been identified in star clusters and in field populations in our own Milky Way galaxy and in its satellite galaxies. They manifest as stars bluer and more luminous than the dominant old population, and…
Abridged... Blue stragglers (BSS) are thought to be the product of either primordial or collisional binary systems. In the context of dwarf spheroidal galaxies it is hard to firmly disentangle a genuine BSS population from young main…
Blue straggler stars are the most prominent bright objects in the colour-magnitude diagram of a star cluster that challenges the theory of stellar evolution. Star clusters are the closest counterparts of the theoretical concept of simple…