Related papers: Constraints on Core Collapse from the Black Hole M…
The first direct detection of gravitational waves in 2015 marked the beginning of a new era for the study of compact objects. Upcoming detectors, such as the Einstein Telescope, are expected to add thousands of binary coalescences to the…
For a long time Gerry Brown and his collaborator Hans Bethe considered the question of the final fate of a core collapse (Type II) supernova. Recalling ideas from nuclear structure on Kaon condensate and a soft equation of state of the…
Collapsing supermassive stars ($M \gtrsim 3 \times 10^4 M_{\odot}$) at high redshifts can naturally provide seeds and explain the origin of the supermassive black holes observed in the centers of nearly all galaxies. During the collapse of…
Current stellar evolution models predict that during the core collapse of massive stars, a considerable amount of the stellar material will fall back onto the compact, collapsed remnants (neutron stars or black holes), usually in the form…
We perform axisymmetric simulations of the magnetorotational collapse of very massive stars in full general relativity. Our simulations are applicable to the collapse of supermassive stars (M > 10^3M_sun) and to very massive Pop III stars.…
The detection of the binary black hole merger GW190521, with primary black hole mass $85^{+21}_{-14}$ ${\rm M}_{\odot}$, proved the existence of black holes in the theoretically predicted pair-instability gap ($\sim60-120 \, {\rm…
We investigate the impact of stellar rotation on the formation of black holes (BHs), by means of our population-synthesis code SEVN. Rotation affects the mass function of BHs in several ways. In massive metal-poor stars, fast rotation…
Both the recently observed high runaway velocities of Cyg X-1 (~50 km/s) and X-ray Nova Sco 1994 (> ~100 km/s) and the relatively low radial velocities of the black hole X-ray binaries with low mass donor stars, can be explained by…
In this paper we discuss the evolution of gravitationally unstable pre-galactic discs that result from the collapse of haloes at high redshift $z \approx 10$ or so, which have not yet been enriched by metals. In cases where molecular…
The core collapse of rapidly rotating massive ~10 Msun stars ("collapsars"), and resulting formation of hyper-accreting black holes, are a leading model for the central engines of long-duration gamma-ray bursts (GRB) and promising sources…
To explain the observed population of supermassive black holes at z~7, very massive seed black holes or, alternatively, super-Eddington scenarios are needed to reach final masses of the order of 10^9 solar masses. A popular explanation for…
(Simplified) We present a theoretical framework which establishes how the core radius of a star cluster varies with the mass of an assumed central black hole. Our result is that the ratio of core to half-mass radius varies as the 3/4 power…
Recent literature on core-collapse supernovae suggests that a black hole (BH) can form within $\sim 1$ s of shock revival, while still culminating in a successful supernova. We refer to these as black hole supernovae, as they are distinct…
Mass estimates, based on scaling relationships, are presented of central black holes in luminous quasars at a range of redshifts (z < 0.5, 1.2 ~< z ~< 6.3). The data show that very massive (about 10^9 solar masses or larger) black holes…
Recently (Brown \& Bethe 1994) it was suggested that most stars with main sequence mass in the range of about $18 - 30 M_{\odot}$ explode, returning matter to the Galaxy, and then go into low-mass ($\geq 1.5 M_{\odot}$) black holes. Even…
We revisit the conditions present in supermassive discs (SMDs) formed by the merger of gas-rich, metal-enriched galaxies at red-shift $z\sim 10$. We find that SMDs naturally form hydrostatic cores which go through a rapidly accreting…
We consider a scenario where supermassive black holes form through direct accumulation of gas at the centre of proto-galaxies. In the first stage, the accumulated gas forms a super-massive star whose core collapses when the nuclear fuel is…
The recent detection of GW190521 stimulated ideas on how to populate the predicted black hole pair-instability mass gap. One proposed scenario is the dynamical merger of two stars below the pair instability regime forming a star with a…
We demonstrate that $\sim10\,\textrm{s}$ after the core-collapse of a massive star, a thermonuclear explosion of the outer shells is possible for some (tuned) initial density and composition profiles, assuming that the neutrinos failed to…
The explosion of core-collapse supernovae (CCSNe) is an extremely challenging problem, and there are still large uncertainties regarding which stars lead to successful explosions that leave behind a neutron star, and which ones will form a…