Related papers: Open Cluster Evolutions in Binary System: How They…
We use a hybrid N-body program to study the evolution of massive black hole binaries in the centers of galaxies, mainly to understand the factors affecting the binary eccentricity, the response of the galaxy to the binary merger, and the…
The discovery of Exoplanetary Systems has challenged some of the theories of planet formation, which assume unperturbed evolution of the host star and its planets. However, in star clusters the interactions with flyby stars and binaries may…
Most, if not all, stars in the field are born in binary configurations or higher multiplicity systems. In dense stellar environment such as the Galactic Center (GC), many stars are expected to be in binary configurations as well. These…
The high-density environment of galaxy clusters is ripe for collisional encounters of galaxies. While the large velocity dispersion of clusters was originally thought to preclude slow encounters, the infall of smaller groups into the…
A dense-enough gas-accumulation evolves, over a few Myr of intensifying star formation, to an embedded cluster. If it contains a sufficient amount of mass, O stars form and explosively expel the remaining gas, whereas poorer clusters reduce…
[abridged] We present a unified picture for the evolution of star clusters on the two-body relaxation timescale. We use direct N-body simulations of star clusters in a galactic tidal field starting from different multi-mass King models, up…
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…
Be stars are rapidly rotating B type stars. The origin of their rapid rotation is not certain, but binary interaction remains to be a possibility. In this work we investigate the formation of Be stars resulting from mass transfer in…
When the primary star in a close binary system evolves into a giant and engulfs its companion, its core and the companion temporarily orbit each other inside a common envelope. Drag forces transfer orbital energy and angular momentum to the…
Understanding the formation of wide binary systems of very low mass stars (M $\le$ 0.1 Msun) is challenging. The most obvious route is via widely separated low-mass collapsing fragments produced through turbulent fragmentation of a…
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 are often born in triples, where gravitational dynamics and stellar interactions play a crucial role in shaping their evolution. One such pathway includes the merger of the inner binary, transforming the system to a binary…
We develop a semi-analytic model to investigate how accretion onto wide low-mass binary stars can result in a close high-mass binary system. The key ingredient is to allow mass accretion while limiting the gain in angular momentum. We…
The search for satellites around exoplanets represents one of the greatest challenges in advancing the characterization of planetary systems. Currently, we can only detect massive satellites, which resemble additional planetary companions…
Tight and compact binary systems, such as double neutron star binaries, are believed to undergo a common envelope evolution phase, resulting in strongly bound orbits. During this phase, the outer layers of the primary star are expelled,…
We analyze the dynamical evolution of binary stars that interact with a static background of single stars in the environment of a massive black hole (MBH). All stars are considered to be single mass, Newtonian point particles. We follow the…
In a series of three papers, we introduced a novel cluster formation model that describes the formation, growth, and disruption of star clusters in high-resolution cosmological simulations. We tested this model on a Milky Way-sized galaxy…
The evolution of galaxies is driven strongly by dynamical processes including internal instabilities, tidal interactions and mergers. The cluster environment is a useful laboratory for studying these effects. I present recent results on…
As of today over 40 planetary systems have been discovered in binary star systems. In all cases the configuration appears to be circumstellar, where the planets orbit around one of the stars, the secondary acting as a perturber. The…
It is widely believed that central star binarity plays an important role in the formation and evolution of aspherical planetary nebulae, however observational support for this hypothesis is lacking. Here, we present the most recent results…