Related papers: Contribution of primordial binary evolution to the…
The presence of a nearby companion alters the evolution of massive stars in binary systems, leading to phenomena such as stellar mergers, X-ray binaries and gamma-ray bursts. Unambiguous constraints on the fraction of massive stars affected…
Stars are mostly found in binary and multiple systems, as at least 50% of all solar-like stars have companions - a fraction that goes up to 100% for the most massive stars. Moreover, a large fraction of them will interact in some way or…
Observations and theoretical work suggest that globular clusters may be born with initially very large binary fractions. We present first results from our newly modified Monte-Carlo cluster evolution code, which treats binary interactions…
Based on over 3000 BV images of M4 collected in years 1995-2009 we obtain light curves of 22 variables, 10 of which are newly detected objects. We identify four detached eclipsing binaries and eight contact binaries. Accurate periods are…
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…
Binary stars are pairs of stars that are gravitationally bound, providing in some cases accurate measurements of their masses and radii. As such, they serve as excellent testbeds for the theory of stellar structure and evolution. Moreover,…
Orbital evolution of binary systems in dense stellar clusters is important in a variety of contexts: origin of blue stragglers, progenitors of compact object mergers, millisecond pulsars, and so on. Here we consider the general problem of…
Because the majority of massive stars are born as members of close binary systems, populations of massive main-sequence stars contain stellar mergers and products of binary mass transfer. We simulate populations of massive stars accounting…
By combining high-resolution HST and wide-field ground based observations, in ultraviolet and optical bands, we study the Blue Stragglers Star (BSS) population of the galactic globular cluster M5 (NGC 5904) from its very central regions up…
The basic properties of the candidate binary cluster population in the Magellanic Clouds and Galaxy are similar. The fraction of candidate binary systems is $\sim$10% and the pair separation histogram exhibits a bimodal distribution…
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…
Binary stars play a major role in determining the dynamic evolution of star clusters. We used images collected with the Hubble Space Telescope to study fourteen Magellanic Clouds star clusters that span an age interval between $\sim 0.6$…
Since the majority of massive stars are members of binary systems, an understanding of the intricacies of binary interactions is essential for understanding the large variety of supernova types and sub-types. I therefore briefly review the…
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…
Massive stars often evolve in binary systems, in which binary interactions significantly affect their evolution. Massive stars in the Galaxy serve as valuable testbeds for this due to their proximity. We computed the evolution of more than…
It is now clear that a binary pathway is responsible for a significant fraction of planetary nebulae, and the continually increasing sample of known central binaries means that we are now in a position to begin to use these systems to…
(Abridged) Following on from a recently completed radial-velocity survey of the old (7 Gyr) open cluster NGC 188 in which we study in detail the solar-type hard binaries and blue stragglers of the cluster, here we investigate the dynamical…
The dynamics of a close binary system of globular clusters is considered. It is shown that the star transfer process from one of the components to the other should lead to the decrease of dimension of the first cluster with simultaneous…
Context. The majority of massive stars are born with a close binary companion. How this affects their evolution and fate is still largely uncertain, especially at low metallicity. Aims. We derive synthetic populations of massive…
Characterization of the binary fractions in star clusters is of fundamental importance for many fields in astrophysics. Observations indicate that the majority of stars are found in binary systems, while most stars with masses greater than…