Related papers: An apparent positive relation between spin and orb…
We study the evolution of the orientation of the orbital plane of massive black hole binaries (BHBs) in rotating stellar systems in which the total angular momentum of the stellar cusp is misaligned with respect to that of the binary. We…
The spin of a black hole is an important quantity to study, providing a window into the processes by which a black hole was born and grew. Further, spin can be a potent energy source for powering relativistic jets and energetic particle…
We performed direct N-body simulations of open clusters with four different metallicities. To investigate the effective spins of merging binary black holes (BBHs) originated from these open clusters, we calculated the spin evolution of…
We use a combination of a cosmological N-body simulation of the concordance Lambda cold dark matter (LCDM) paradigm and a semi-analytic model of galaxy formation to investigate the spin development of central supermassive black holes (BHs)…
We perform numerical simulations of black-hole binaries to study the exchange of spin and orbital angular momentum during the last, highly nonlinear, stages of the coalescence process. To calculate the transfer of angular momentum from…
Studies of the observed characteristics of black-hole (BH) X-ray binaries can be provide us with valuable information about the process of BH formation. In this paper I address some of the aspects of our current understanding of BH…
GW231123, the most massive binary black hole (BBH) merger detected by LIGO/Virgo/KAGRA, highlights the need to understand the origins of massive, high-spin stellar black holes (BHs). Dense star clusters provide natural environments for…
Spin parameters of stellar-mass black holes in X-ray binaries are currently being estimated by fitting the X-ray continuum spectra of their accretion disk emission. For this method, it is necessary to know the inclination of the…
Black hole (BH) spin can play an important role in galaxy evolution by controlling the amount of energy and momentum ejected from near the BH into the surroundings. We focus on radiatively-inefficient and geometrically-thick…
Context. Ultracompact X-ray binaries (UCXBs) typically consist of a white dwarf donor and a neutron star or black hole accretor. The evolution of UCXBs and very low mass ratio binaries in general is poorly understood. Aims. We investigate…
We study the spin evolution of X-ray neutron stars in binary systems, which are being spun up by mass transfer from accretion disks. Our investigation reveals that a quark phase transition resulting from the changing central density induced…
The age of gravitational wave (GW) astronomy has begun, and black hole (BH) mergers detected by LIGO are providing novel constraints on massive star evolution. A major uncertainty in stellar theory is the angular momentum (AM) transport…
A low mass X-ray binary (LMXB) contains either a neutron star or a black hole accreting materials from its low mass companion star. It is one of the primary astrophysical sources for studying the stellar size compact objects and the…
The identification of the first confirmed neutron star - black hole (NS-BH) binary mergers by the LIGO, Virgo and KAGRA collaboration provides the opportunity to investigate the properties of the early sample of confirmed and candidate…
Massive black hole (MBH) binary inspiral time scales are uncertain, and their spins are even more poorly constrained. Spin misalignment, along with unequal mass ratios and spin magnitudes, introduces asymmetry in the gravitational…
Recent discoveries have confirmed the existence of a large population of X-ray sources fuelled by accretion from the stellar wind of an OB supergiant. Such systems are powerful laboratories to study many aspects of astrophysics. Over the…
We study the evolution of a low mass x-ray binary coupling a binary stellar evolution code with a general relativistic code that describes the behavior of the neutron star. We assume the neutron star to be low--magnetized (B~10^8 G). In the…
Using recent results from numerical relativity simulations of black hole mergers, we revisit previous studies of cosmological black hole spin evolution. We show that mergers are very unlikely to yield large spins, unless alignment of the…
Radio pulsars with millisecond spin periods are thought to have been spun up by transfer of matter and angular momentum from a low-mass companion star during an X-ray-emitting phase. The spin periods of the neutron stars in several such…
A large fraction of black hole low-mass X-ray binaries (BHLMXBs) are in short period orbits, which require strong orbital angular momentum loss during the previous evolutionary stage. Ivanova (2006) put forward the possibility that some of…