Related papers: Disk formation in the collapse of supramassive neu…
Short Gamma-Ray Bursts (GRBs) are explosions of cosmic origin believed to be associated with the merger of two compact objects, either two neutron stars, or a neutron star and a black hole. The presence of at least one neutron star has long…
We analyze here late evolutionary stages of massive (with initial mass higher than 8 masses of the Sun) close binary stars. Our purposes are to study possible mechanisms of gamma ray bursts (GRBs) origin. We suppose in this paper that GRB…
Context. The coincident detection of GW170817 and GRB170817A marked a milestone for the connection between binary neutron star (BNS) mergers and short gamma-ray bursts (sGRBs). These mergers can lead to the formation of a black hole…
Recent observations of short gamma-ray bursts (SGRBs) suggest that binary neutron star (NS) mergers can create highly magnetised, millisecond NSs. Sharp cut-offs in X-ray afterglow plateaus of some SGRBs hint at the gravitational collapse…
We study the evolution in axisymmetry of accretion disks formed self-consistently through collapse of magnetized hypermassive neutron stars to black holes. Such stars can arise following the merger of binary neutron stars. They are…
Growing evidence connects the progenitor systems of the short-hard subclass of gamma-ray bursts (GRBs) to the merger of compact object binaries composed by two neutron stars (NSs) or by a NS and a black hole (BH). The recent observation of…
The central engine of short gamma-ray bursts (sGRBs) is hidden from direct view, operating at a scale much smaller than that probed by the emitted radiation. Thus we must infer its origin not only with respect to the formation of the {\it…
The recent localization of some short-hard gamma ray bursts (GRBs) in galaxies with low star formation rates has lent support to the suggestion that these events result from compact object binary mergers. We discuss how new simulations in…
Short Gamma-Ray Bursts (SGRBs) are among the most luminous explosions in the universe, releasing in less than one second the energy emitted by our Galaxy over one year. Despite decades of observations, the nature of their "central-engine"…
Gamma-ray bursts (GRBs), both long and short, are explosive events whose inner engine is generally expected to be a black hole or a highly magnetic neutron star (magnetar) accreting high density matter. Recognizing the nature of GRB central…
We consider the gamma ray burst (GRB) central engine that is powered by the collapse of a massive rotating star or compact binary merger. The engine is a hot and dense accretion disk, which is composed of free nucleons, electron-positron…
A variety of arguments suggest that the most common form of gamma-ray bursts (GRBs), those longer than a few seconds, involve the formation of black holes in supernova-like events. Two kinds of ``collapsar'' models are discussed, those in…
A diverse range of phenomena is possible when a black hole experiences very rapid accretion from a disk due to the incomplete explosion of a massive presupernova star endowed with rotation. In the most extreme case, the outgoing shock fails…
The accretion of ~ 0.1 -- 1 M_o of material by a neutron star through Roche lobe overflow of its companion or through white-dwarf/neutron-star coalescence in a low mass binary system could be enough to exceed the critical mass of a neutron…
Short-duration gamma-ray bursts (sGRBs) are commonly attributed to the mergers of double neutron stars (NSs) or the mergers of a neutron star with a black hole (BH). While the former scenario was confirmed by the event GW170817, the latter…
We elucidate the feature of gravitational waves (GWs) from binary neutron star merger collapsing to a black hole by general relativistic simulation. We show that GW spectrum imprints the coalescence dynamics, formation process of disk,…
Inspiraling and merging binary neutron stars are not only important source of gravitational waves, but also promising candidates for coincident electromagnetic counterparts. These systems are thought to be progenitors of short gamma-ray…
The collapsar model was proposed to explain the long-duration gamma-ray bursts (GRBs), while the short GRBs are associated with the mergers of compact objects. In the first case, mainly the energetics of the events is consistent with the…
In this work we estimate the accretion-disk mass in the specific scenario of binary-neutron-star-merger with current observational data. Assuming that the outflows of short Gamma-ray Bursts (GRBs) are driven via neutrino-antineutrino…
Cosmological gamma ray bursts (GRBs) are thought to occur from violent hypercritical accretion onto stellar mass black holes, either following core collapse in massive stars or compact binary mergers. This dichotomy may be reflected in the…