Related papers: Black Hole Emergence in Supernovae
Since a black hole does not emit light from its interior, nor does it have a surface on which light from nearby sources can be reflected, observational study of black hole physics requires observing the gravitational impact of the black…
Black holes are popping up all over the place: in compact binary X-ray sources and GRBs, in quasars, AGNs and the cores of all bulge galaxies, in binary black holes and binary black hole-neutron stars, and maybe even in the LHC! Black holes…
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…
Only a small fraction of local galaxies harbor an accreting black hole, classified as an active galactic nucleus (AGN). However, many stellar systems are plausibly expected to host black holes, from globular clusters to nuclear star…
Rapid formation of supermassive black holes occurs in dense nuclear star clusters that are initially gas-dominated. Stellar-mass black hole remnants of the most massive cluster sink into the core, where a massive runaway black hole forms as…
We study the problem of steady-state spherical accretion onto a black hole, in which the internal energy of the flow is governed by radiation and photon diffusion dominates the energy flux at large radii. In the free-fall limit, the fluid…
We study the detectability of neutrino bursts from nearby direct black hole-forming collapses (failed supernovae) at Megaton detectors. Due to their high energetics, these bursts could be identified - by the time coincidence of N >= 2 or N…
Observation of an exploding black hole would provide the first direct evidence of primordial black holes, the first direct evidence of Hawking radiation, and definitive information on the particles present in nature. However, indirect…
The gravitational collapse of a non-rotating, black-hole-forming massive star is studied by neutrino-radiation-hydrodynamical simulations for two different sets of realistic equation of state of dense matter. We show that the event will…
Supermassive black holes with up to a $\rm 10^{9}~M_{\odot}$ dwell in the centers of present-day galaxies, and their presence has been confirmed at z $\geq$ 6. Their formation at such early epochs is still an enigma. Different pathways have…
Recently, stellar collapse involving black hole formation from massive stars is suggested to emit enormous fluxes of neutrinos on par with ordinary core-collapse supernovae. We investigate their detectability for the currently operating…
In general relativity, isolated black holes are invisible due to an infinitely large redshift of photons propagating from the event horizon to the remote observer. However, the dark shadow (silhouette) of a black hole can be visible on the…
While it is well known that neutrinos are emitted from standard core collapse protoneutron star supernovae, less attention has been focused on neutrinos from accretion disks. These disks occur in some supernovae (i.e. "collapsars") as well…
While large numbers of supermassive black holes have been detected at z>6, their origin is still essentially unclear. Numerical simulations have shown that the conditions for the classical direct collapse scenario are very restrictive and…
Black holes are by definition black, and therefore cannot be directly observed by using electromagnetic radiations. Convincing identification of black holes must necessarily depend on the identification of a very specially behaving matter…
We find radiation in an infalling frame and present an explicit analytic evidence of the failure of no drama condition by showing that an infalling observer finds an infinite negative energy density at the event horizon. The negative and…
Neutron stars inspiralling into a stellar envelope can accrete at rates vastly exceeding the Eddington limit if the flow develops pressures high enough to allow neutrinos to radiate the released gravitational energy. It has been suggested…
Black holes are capable of reflection: there is a finite probability for any particle that approaches the event horizon to bounce back. The albedo of the black hole depends on its temperature and the energy of the incoming particle. The…
Space telescope observations of massive black holes during their formation may be key to understanding the origin of supermassive black holes and high-redshift quasars. To create diagnostics for their detection and confirmation, we study a…
Massive primordial halos exposed to moderate UV backgrounds are the potential birthplaces of supermassive black holes. In such a halo, an initially isothermal collapse will occur, leading to high accretion rates of…