Related papers: On the Assembly Rate of Highly Eccentric Binary Bl…
The ongoing observations from ground based gravitational-wave observatories have led to the detection of more than a hundred merger events between black holes. We use the LIGO-Virgo-KAGRA (LVK) observations from 2015 to early 2024, to test…
We review the theory behind the formation of primordial black hole binaries and their merger rates. We consider the binary formation in the early and late Universe, emphasising the former as it gives the dominant contribution of the present…
Dense star clusters are thought to contribute significantly to the merger rates of stellar-mass binary black holes (BBHs) detected by the LIGO-Virgo-KAGRA collaboration. We combine $N$-body dynamic models of realistic dense star clusters…
Recently, the LIGO-Virgo collaborations have reported the coalescence of a binary involving a black hole and a low-mass gap object (LMGO) with mass in the range $\sim2.5-5M_\odot$. Such detections, challenge our understanding of the black…
In order to investigate the formation rate of binary black holes (BBHs) in stellar clusters with a mass comparable to open clusters, we performed a series of direct $N$-body simulations of open clusters with a mass of $2.5\times10^3$ (Model…
We use a 3-D relativistic SPH (Smoothed Particle Hydrodynamics) code to study mergers of black hole -- neutron star (BH--NS) binary systems with low mass ratios, adopting $M_{NS}/M_{BH} \simeq 0.1$ as a representative case. The outcome of…
Black hole - neutron star $(BH/NS)$ binaries are of interest in many ways: they are intrinsically multi-messenger systems, highly transient, radiate gravitational waves detectable by LIGO, and may produce $\gamma$-ray bursts. Although it…
Binary black holes (BBHs) born from the evolution of Population III (Pop. III) stars are one of the main high-redshift targets for next-generation ground-based gravitational-wave (GW) detectors. Their predicted initial mass function and…
Galactic nuclei are expected to be one of the main sites for formations of eccentric binary black holes (EBBHs), with an estimated detection rate of $\mathcal{O}(1-100$ yr$^{-1})$ with Advanced LIGO (aLIGO) detectors operating at design…
In galactic centers, stars and binaries can be injected into low-angular-momentum orbits, resulting in close encounters with the central supermassive black hole (SMBH). Previous works have shown that under different conditions, such close…
Motivated by the increasing number of detections of merging black holes by LIGO-VIRGO-KAGRA, black hole (BH) binary mergers in the discs of active galactic nuclei (AGN) is investigated as a possible merger channel. In this pathway, BH…
The binary black hole mergers observed by LIGO-Virgo gravitational-wave detectors pose two major challenges: (i) how to produce these massive black holes from stellar processes; and (ii) how to bring them close enough to merge within the…
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,…
We present preliminary results from self-consistent, high resolution direct {\it N}-body simulations of massive black hole binaries in mergers of galactic nuclei. The dynamics of the black hole binary includes the full Post-Newtonian…
The LIGO/Virgo collaboration have by now detected the mergers of ten black hole binaries via the emission of gravitational radiation. The hypothesis that these black holes have formed during the cosmic QCD epoch and make up all of the…
Primordial black holes (PBHs), possibly constituting a non-negligible fraction of dark matter (DM), might be responsible for a number of gravitational wave events detected by LIGO/Virgo/KAGRA. In this paper, we simulate the evolution of PBH…
Despite the increasing number of Gravitational Wave (GW) detections, the astrophysical origin of Binary Black Hole (BBH) mergers remains elusive. A promising formation channel for BBHs is inside accretion discs around supermassive black…
Recent detections of gravitational waves from mergers of neutron stars (NSs) and black holes (BHs) in the low and high-end mass gap regimes pose a puzzle to standard stellar and binary evolution theory. Mass-gap mergers may originate from…
The recent binary black hole (BH) merger GW231123, with both components likely in the high-mass gap and with high spins, challenges standard BH binary formation models. It is usually thought that the BHs are of second (or higher) generation…
The gravitational-wave signal from the neutron star-black hole (NSBH) merger GW200105 is consistent with this binary having significant orbital eccentricity close to merger. This raises the question of how eccentric NSBHs form. Compact…