Related papers: Coalescing binary systems of compact objects: Dyna…
We investigate the formation of binary stellar systems. We consider a model where a `seed' protobinary system forms, via fragmentation, within a collapsing molecular cloud core and evolves to its final mass by accreting material from an…
While contact binary objects are common in the solar system, their formation mechanism is unclear. In this work we examine several contact binaries and calculate the necessary strength parameters that allow the two lobes to merge without…
Binary stars are thought to be a controlling factor in globular cluster evolution, since they can heat the environmental stars by converting their binding energy to kinetic energy during dynamical interactions. Through such interaction, the…
Gravitational-wave interferometers are expected to monitor the last three minutes of inspiral and final coalescence of neutron star and black hole binaries at distances approaching cosmological, where the event rate may be many per year.…
Knowledge of the spin of the black hole resulting from the merger of a generic black-hole binary is of great importance for studying the cosmological evolution of supermassive black holes. Several attempts have been made to model the spin…
Supermassive black hole binaries may form as a consequence of galaxy mergers. Both prograde and retrograde orbits have been proposed. We study a binary of a small mass ratio, q, in a retrograde orbit immersed in and interacting with a…
As 2 black holes bound to each other in a close binary approach merger their inspiral time becomes shorter than the characteristic inflow time of surrounding orbiting matter. Using an innovative technique in which we represent the changing…
In this article, we focus on the effects of mass transfer between binary stars and stellar spin on the post-Newtonian (PN) orbital evolution and gravitational waveforms of compact binary systems. We employ the 2.5PN approximation and the…
Mass transfer in binary systems is the key process in the formation of various classes of objects, including merging binary black holes (BBHs) and neutron stars. Orbital evolution during mass transfer depends on how much mass is accreted…
We examine the proposal that the subset of neutron-star and black-hole X-ray binaries that form with Ap or Bp star companions will experience systemic angular-momentum losses due to magnetic braking, not otherwise operative with…
We investigate close binary neutron stars in quasiequilibrium states in a general relativistic framework. We assume conformal flatness for the spatial metric and irrotational velocity field for the neutron stars. We adopt the polytropic…
Spin precession occurs in binary black holes whose spins are misaligned with the orbital angular momentum. Otherwise, the spin configuration is constant and the subsequent binary dynamics and gravitational-wave emission are much simpler. We…
Boson stars have attracted much attention in recent decades as simple, self-consistent models of compact objects and also as self-gravitating structures formed in some dark-matter scenarios. Direct detection of these hypothetical objects…
The common envelope phase of binary star evolution plays a central role in many evolutionary pathways leading to the formation of compact objects in short period systems. Using three dimensional hydrodynamical computations, we review the…
The coalescence of massive black hole binaries is one of the main sources of low-frequency gravitational radiation that can be detected by LISA. When two galaxies containing massive black holes merge, a binary forms at the center of the new…
We report on a search for gravitational waves from coalescing compact binaries using LIGO and Virgo observations between July 7, 2009 and October 20, 2010. We searched for signals from binaries with total mass between 2 and 25 solar masses;…
What happens to a neutron star or white dwarf near its maximum mass limit when it is brought into a close binary orbit with a companion? Such situation may occur in the progenitors of Type Ia supernovae and in coalescing neutron star…
We launch a fully relativistic study of the formation of supermassive black holes via the collapse of supermassive stars. Here we initiate our investigation by analyzing the secular evolution of supermassive stars up to the onset of…
Our current understanding of the physical processes of star formation is reviewed, with emphasis on processes occurring in molecular clouds like those observed nearby. The dense cores of these clouds are predicted to undergo gravitational…
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…