Related papers: Estimating the outcomes of common envelope evoluti…
We study the dynamical evolution of a stellar disk orbiting a massive black hole. We explore the role of two-body relaxation, mass segregation, stellar evolution and binary heating in affecting the disk evolution, and consider the impact of…
The orbital decay of binaries containing a primary sub-giant or red giant star and a stellar or substellar companion is investigated. The tide raised in the primary by the companion leads to an exchange of angular momentum between the orbit…
We study orbital inclination changes associated with the precession of a disc-planet system that occurs through gravitational interaction with a binary companion on an inclined orbit. We investigate whether this scenario can account for…
We present results from a suite of eight direct N-body simulations, performed with \textsc{Nbody6++GPU}, representing realistic models of rotating star clusters with up to $1.1\times 10^5$ stars. Our models feature primordial (hard)…
We present a rapid binary evolution algorithm that enables modelling of even the most complex binary systems. In addition to all aspects of single star evolution, features such as mass transfer, mass accretion, common-envelope evolution,…
The long-term evolution of stellar orbits bound to a massive centre is studied in order to understand the cores of star clusters in central regions of galaxies. Stellar trajectories undergo tiny perturbation, the origin of which is twofold:…
We review three main results of our recent study: * We show that a proper treatment of the tidal interaction prior to the onset of the common envelope (CE) leads to an enhance mass loss. This might increase the survivability of planets and…
We use the binary module of the MESA code to study the evolution of an evolved binary system where we assume that a main sequence companion removes the outskirts of the envelope of an asymptotic giant branch (AGB) star by launching jets,…
A star with main sequence mass greater than $25\sim 30\msun$ may collapse to a black hole of about 10 $\msun$ at the final stage of the evolution. About an order of 1\% of stellar mass is likely to be in form of such black holes in…
Most stars are members of binaries, and the evolution of a star in a close binary system differs from that of an ioslated star due to the proximity of its companion star. The components in a binary system interact in many ways and binary…
Common envelope evolution is a fundamental ingredient in our understanding of the formation of close binary stars containing compact objects which includes the progenitors of type Ia supernovae, short gamma ray bursts and most stellar…
Simulations of binary neutron stars have seen great advances in terms of physical detail and numerical quality. However, the spin of the neutron stars, one of the simplest global parameters of binaries, remains mostly unstudied. We present…
Evolved stars dominate galactic spectra, enrich the galactic medium, expand to change their planetary systems, eject winds of a complex nature, produce spectacular nebulae and illuminate them, and transfer material between binary…
The common-envelope (CE) phase is a crucial stage in binary star evolution because the orbital separation can shrink drastically while ejecting the envelope of a giant star. Three-dimensional (3D) hydrodynamic simulations of CE evolution…
A number of stellar astrophysical phenomena, such as tidal novae and planetary engulfment, involve sudden injection of sub-binding energy in a thin layer within the star, leading to mass ejection of the stellar envelope. We use a 1D…
At least $70\%$ of massive OBA-type stars reside in binary or higher-order systems. The dynamical evolution of these systems can lend insight into the origins of extreme phenomena such as X-ray binaries and gravitational wave sources. In…
It is debated whether close-in giant planets can form in-situ and if not, which mechanisms are responsible for their migration. One of the observable tests for migration theories is the current value of the angle between the stellar…
The stellar origin of gamma-ray bursts can be explained by the rapid release of energy in a highly collimated, extremely relativistic jet. This in turn appears to require a rapidly spinning highly magnetised stellar core that collapses into…
We study the evolution of embedded clusters. The equations of motion of the stars in the cluster are solved by direct N-body integration while taking the effects of stellar evolution and the hydrodynamics of the natal gas content into…
Modeling the evolution of progenitors of gravitational-wave merger events in binary stars faces two major uncertainties: the common-envelope phase and supernova kicks. These two processes are critical for the final orbital configuration of…