Related papers: A Binary Origin for Blue Stragglers in Globular Cl…
The dense central region of NGC 6397 contains three classes of stars whose origins are likely related to stellar interactions: blue stragglers, cataclysmic variables, and probable helium white dwarfs. We summarize results concerning CVs and…
Dynamical interactions that take place between objects in dense stellar systems lead to frequent formation of exotic stellar objects, unusual binaries, and systems of higher multiplicity. They are most important for the formation of…
We summarize current models of the formation of spheroidal stellar systems. Whereas globular clusters form in an efficient mode of star formation inside turbulent molecular clouds, the origin of galactic spheroids, that is bulges, dwarf…
Enhancement and spread of helium among globular cluster stars have been recently suggested as a way to explain the horizontal branch blue tails, in those clusters which show a primordial spread in the abundances of CNO and other elements…
When two stars collide and merge they form a new star that can stand out against the background population in a starcluster as a blue straggler. In so called collision runaways many stars can merge and may form a very massive star that…
Observations revealed the presence of multiple stellar populations in globular clusters (GCs) that exhibit wide abundance variations and multiple sequences in Hertzsprung-Russell (HR) diagram. We present a scenario for the formation of…
Massive stars play a major role in the evolution of their host galaxies, and serve as important probes of the distant Universe. It has been established that the majority of massive stars reside in close binaries and will interact with their…
Using our recently improved Monte Carlo evolution code, we study the evolution of the binary fraction in globular clusters. In agreement with previous N-body simulations, we find generally that the hard binary fraction in the core tends to…
Most galaxies have central massive black holes (BH), and merge with others during their evolution, as strongly suggested by recent observations. Consequently a black hole binary (BHB) emerges. Considering the evolution of the binary when it…
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…
Dynamical friction due to field stars and tidal disruption caused by a central nucleus are crucial in determining the evolution of the globular cluster system in an elliptical galaxy. In this paper I examine the possibility that some of…
Globular cluster systems in most large galaxies display bimodal color and metallicity distributions, which are frequently interpreted as indicating two distinct modes of cluster formation. The metal-rich (red) and metal-poor (blue) clusters…
One of the principal mechanisms that is responsible for the origin of blue stragglers is mass transfer that takes place while one of the binary companions overfills its Roche lobe. In this Chapter, we overview the theoretical understanding…
Sub-subgiants are a new class of stars that are optically redder than normal main-sequence stars and fainter than normal subgiant stars. Sub-subgiants, and the possibly related red stragglers (which fall to the red of the giant branch),…
The impact of stellar rotation on the morphology of star cluster colour-magnitude diagrams is widely acknowledged. However, the physics driving the distribution of the equatorial rotation velocities of main-sequence turn-off (MSTO) stars is…
Observations have revealed that most stars are born in clusters. These systems, containing from tens to thousands of stars and typically significant mass in gas in the youngest systems, evolve due to a combination of stellar and star-gas…
Abundance anomalies observed in globular cluster stars indicate pollution with material processed by hydrogen burning. Two main sources have been suggested: asymptotic giant branch stars and massive stars rotating near the break-up limit.…
The overall frequency and other statistical properties of binary systems suggest that star formation is intrinsically a complex and chaotic process, and that most binaries and single stars actually originate from the decay of multiple…
We present a detailed investigation of the radial distribution of blue straggler star and binary populations in the Galactic globular cluster NGC 5466, over the entire extension of the system. We used a combination of data acquired with the…
Context. The study of blue straggler stars (BSS) provides insight into the mechanisms of stellar mass exchange during binary stellar evolution and the complex gravitational interactions within dense stellar systems. In combination, they…