Related papers: Boson star-black hole binaries: initial data and h…
The gravitational wave signals of black hole-neutron star (BHNS) binary systems have now been detected, and future detections might be accompanied by electromagnetic counterparts. BHNS mergers involve much of the same physics as binary…
Black hole-neutron star (BHNS) binaries are important sources of gravitational waves for second-generation interferometers, and BHNS mergers are also a proposed engine for short, hard gamma-ray bursts. The behavior of both the spacetime…
We examine the pairing process of supermassive black holes (SMBHs) down to scales of 20-100 pc using a set of N-body/SPH simulations of binary mergers of disk galaxies with mass ratios of 1:4 and 1:10. Our numerical experiments are designed…
The coalescence of massive black hole binaries (BHBs) in galactic mergers is the primary source of gravitational waves (GWs) at low frequencies. Current estimates of GW detection rates for the Laser Interferometer Space Antenna and the…
We investigate black hole-star binaries formed in $N$-body simulations of massive, dense star clusters. We simulate 32 clusters with varying initial masses ($10^{4}~\rm M_{\odot}$ to $10^{6}~\rm M_{\odot}$), densities ($1200~\rm…
The recent discovery of the binary black hole (BBH) merger event GW190521, between two black holes (BHs) of $\approx100M_\odot$, and as well as other massive BBH merger events involving BHs within the pair-instability supernova (PSN) mass…
The major source of ground-based gravitational wave detectors, the inspiral and merger of comparable mass binary black holes (BBH), consists of a slow quasicircular inspiral, a merger to form a single remnant hole, and the quasinormal…
Axions are a potential dark matter candidate, which may condense and form self gravitating compact objects, called axion stars (ASs). In this work, we study for the first time head-on collisions of relativistic ASs with black holes (BHs)…
We report on key studies on the dynamics of black holes (BHs) in gas-rich galaxy mergers that underscore the vital role played by gas dissipation in promoting BH inspiral down to the smallest scales ever probed with use of high-resolution…
Galaxy centers are residing places for Super Massive Black Holes (SMBHs). Galaxy mergers bring SMBHs close together to form gravitationally bound binary systems which, if able to coalesce in less than a Hubble time, would be one of the most…
If massive black holes (BHs) are ubiquitous in galaxies and galaxies experience multiple mergers during their cosmic assembly, then BH binaries should be common albeit temporary features of most galactic bulges. Observationally, the paucity…
Multi-body dynamical interactions of binaries with other objects are one of the main driving mechanisms for the evolution of star clusters. It is thus important to bring our understanding of three-body interactions beyond the commonly…
Within the next few years gravitational waves (GWs) from merging black holes (BHs) and neutron stars (NSs) may be directly detected, making a thorough theoretical understanding of these systems a high priority. As an additional motivation,…
The recent O4a release from the LIGO-Virgo-KAGRA collaboration, which significantly increased the number of gravitational-wave (GW) detections, reveals features with potentially important astrophysical implications. One notable example is a…
We test the possibility that the black holes (BHs) detected by LIGO-Virgo-KAGRA (LVK) may be cosmologically coupled and grow in mass proportionally to the cosmological scale factor to some power $k$, which may also act as the dark energy…
Liu et al. (2019) recently reported the detection of a 68 [+11/-13] solar mass (Msun) black hole (BH) paired with an 8.2 [+0.9/-1.2] Msun B-type sub-giant star in the 78.9-day spectroscopic binary system LB-1. Such a black hole is over…
We present binary galaxy merger simulations with varying mass ratios and different progenitor morphologies. The simulations include mergers of gas-rich disks (Sp-Sp), of early-type galaxies and disks (E-Sp, mixed mergers), and mergers of…
The discoveries of a number of binary black hole mergers by LIGO and VIRGO has reinvigorated the interest that primordial black holes (PBHs) of tens of solar masses could contribute non-negligibly to the dark matter energy density. Should…
In this paper, based on the action of a complex scalar field minimally coupled to a gravitational field, we numerically obtain a series of massive boson star solutions in a spherically symmetric background with a quartic-order…
We study the dynamical signatures of black hole (BH) and neutron star (NS) binary mergers via Lidov-Kozai oscillations induced by tertiary companions in hierarchical triple systems. For each type of binaries (BH-BH and BH-NS), we explore a…