Related papers: Constraints on the binary black hole hypothesis fo…
Binary systems consisting of an early type star and a black hole (BH) are crucial for understanding various astrophysical phenomena, particularly the origins of detected gravitational wave sources. Be binary systems are expected to…
It has been suggested that primordial black holes (PBHs) of roughly 30 solar masses could make up the dark matter and if so, might account for the recent detections by LIGO involving binary black holes in this mass range. It has also been…
Binary black holes are the primary endpoint of massive stellar evolution. Their properties provide a unique opportunity to constrain binary evolution, which is still poorly understood. In this paper, we predict the inventory of binary black…
Primordial black holes (PBHs) are a fascinating candidate for being the dark matter, albeit one which has been heavily constrained. This review presents an in depth look at those observational constraints, particularly at their nuances and…
Populations of stellar-mass black holes (BHs) in globular clusters (GCs) influence their dynamical evolution and have important implications on one of the main formation channels for gravitational wave sources. Inferring the size of these…
I investigate the roles of cluster dynamics and massive binary evolution in producing stellar-remnant binary black hole (BBH) mergers over the cosmic time. To that end, dynamical BBH mergers are obtained from long-term direct N-body…
The formation of compact stellar-mass binaries is a difficult, but interesting problem in astrophysics. There are two main formation channels: In the field via binary star evolution, or in dense stellar systems via dynamical interactions.…
Significant historic cosmic evolution for the formation rate of stellar black holes is inferred from current theoretical models of the evolution of massive stars, the multiple observations of compact stellar remnants in the near and distant…
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…
In binary black-hole mergers from isolated binary-star evolution, both black holes are from progenitor stars that have lost their hydrogen-rich envelopes by binary mass transfer. Envelope stripping is known to affect the pre-supernova core…
The recent gravitational wave measurements have demonstrated the existence of stellar mass black hole binaries. It is essential for our understanding of massive star evolution to identify the contribution of binary evolution to the…
We present the detection of a 2.0(+1.4,-0.8)x10^4 solar mass black hole (BH) in the stellar cluster G1 (Mayall II), based on data taken with the Space Telescope Imaging Spectrograph onboard the Hubble Space Telescope. G1 is one of the most…
The coalescence of massive black hole binaries (with masses $10^4 - 10^7 M_{\odot}$) leads to gravitational wave emission that is detectable out to high redshifts ($z \sim 20$) with the forthcoming LISA observatory. We combine the…
If massive black holes constitute the dark matter in the halo surrounding the Milky Way, the existence of low mass globular clusters in the halo suggests an upper limit to their mass, $M_{_{BH}}$. We use a combination of the impulse…
Most common formation channels of stellar mass black hole (BH) binaries like the ones observed by LIGO, often assume they are assembled from the direct collapse of massive pre-supernova stars. However, it is still unclear whether the final…
We explore the formation process of a black hole (BH) through the pair-instability collapse of a rotating Population III very massive star in axisymmetric numerical relativity. As the initial condition, we employ a progenitor star which is…
The X-ray source HLX-1 near the spiral galaxy ESO 243-49 is currently the best intermediate-mass black hole candidate. It has a peak bolometric luminosity of $10^{42}$ erg s$^{-1}$, which implies a mass inflow rate of $\sim10^{-4}$ MSun…
Binary black holes (BBHs) can form from the collapsed cores of isolated high-mass binary stars. The masses and spins of these BBHs are determined by the complicated interplay of phenomena such as tides, winds, accretion, common-envelope…
While no gravitational-wave detection of subsolar mass black holes has been confirmed to date, a number of candidate detections invite us to speculate on the origin of such black holes should a detection be confirmed. It is generally…
Hawking (1971) proposed that the Sun may harbor a primordial black hole whose accretion supplies some of the solar luminosity. Such an object would have formed within the first 1 s after the Big Bang with the mass of a moon or an asteroid.…