Related papers: Mass from a third star: transformations of close c…
Triple stars are prevalent within the population of observed stars. Their evolution, compared to binaries, is notably more complex, influenced by unique dynamical, tidal, and mass transfer processes. Understanding these phenomena is…
Among the four black hole binary merger events detected by LIGO, six progenitor black holes have masses greater than 20\,$M_\odot$. The existence of such massive BHs calls for extreme metal-poor stars as the progenitors. An alternative…
Mass exchange and mass loss in close binaries can significantly affect their evolution, but a complete self-consistent theory of these processes is still to be developed. Processes such as radiative shielding due to a~hot-spot region, or…
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…
An accretion disk can be formed around a secondary star in a binary system when the primary companion leaves the Main sequence and starts to lose mass at an enhanced rate. We study the accretion disk evolution and planetary migration in…
The surroundings of massive protostars constitute an accretion disc which has numerically been shown to be subject to fragmentation and responsible for luminous accretion-driven outbursts. Moreover, it is suspected to produce close binary…
We review the dramatic progress in the simulations of compact objects and compact-object binaries that has taken place in the first two decades of the twenty-first century. This includes simulations of the inspirals and violent mergers of…
The observational consequences of the merger scenario for massive star formation are explored and contrasted with the gradual accumulation of mass by accretion. Protostellar mergers may produce high luminosity infrared flares lasting years…
I describe the current state of our knowledge of the mapping between the initial masses of stars and the compact objects -- particularly neutron stars and black holes -- that they produce. Most of that knowledge is theoretical in nature,…
Substellar objects such as brown dwarfs and planets are generally expected to remain detached from their main-sequence host stars unless orbital decay or stellar expansion brings them into contact, leading to rapid engulfment and…
Motivated by suggestions that binaries with almost equal-mass components ("twins") play an important role in the formation of double neutron stars and may be rather abundant among binaries, we study the stability of synchronized close and…
Following merger, a neutron star (NS) binary can produce roughly one of three different outcomes: (1) a stable NS, (2) a black hole (BH), or (3) a supra-massive, rotationally-supported NS, which then collapses to a BH following angular…
We estimate the observed distribution of chirp masses of compact object binaries for the gravitational wave detectors. The stellar binary evolution is modeled using the {\em StarTrack} population synthesis code. The distribution of the…
The detection of gravitational waves from coalescing binary neutron stars represents another milestone in gravitational-wave astronomy. However, since LIGO is currently not as sensitive to the merger/ringdown part of the waveform, the…
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…
Two long-duration gamma-ray bursts were recently discovered with kilonovae, the signature of r-process element production in a compact binary merger, rather than supernovae. This has forced a re-evaluation of the long-established dichotomy…
In recent years, the existence of a gap in the mass spectrum of compact objects formed from stellar collapse, between the heaviest neutron stars and the lightest black holes, has been a matter of significant debate. The presence or absence…
Rapidly rotating stars are readily produced in binary systems. An accreting star in a binary system can be spun up by mass accretion and quickly approach the break-up limit. Mergers between two stars in a binary are expected to result in…
Depending principally on mass, the compact object remnant left behind after a star's life may be a white dwarf (WD), neutron star (NS), or black hole (BH). While we have large samples of each of these remnants, we lack knowledge of the…
Merging compact binaries are the one source of gravitational radiation so far identified. Because short-period systems which will merge in less than a Hubble time have already been observed as binary pulsars, they are important both as…