Related papers: The division between weak and strong explosions fr…
A star with main sequence mass greater than $25\sim 30\msun$ may collapse to a black hole of about 10 $\msun$ at the final stage of the evolution. About an order of 1\% of stellar mass is likely to be in form of such black holes in…
Supernovae are the most powerful cosmic sources of MeV neutrinos. These elementary particles play a crucial role when the evolution of a massive star is terminated by the collapse of its core to a neutron star or a black hole and the star…
Assuming a Salpeter initial mass function and taking the solar abundances as a representative sample, we explore the sensitivity of nucleosynthesis in massive stars to the truncation of supernova explosions above a certain mass. It is…
We investigate in this paper the core-collapse supernova explosion mechanism in both one and two dimensions. We verify the usefulness of neutrino-driven overturn (``convection'') between the shock and the neutrinosphere in igniting the…
We explore with self-consistent 2D F{\sc{ornax}} simulations the dependence of the outcome of collapse on many-body corrections to neutrino-nucleon cross sections, the nucleon-nucleon bremsstrahlung rate, electron capture on heavy nuclei,…
Neutrino losses from proto-neutron stars play a pivotal role to decide if these stars would be crushed into black holes or explode as supernovae. Recent observations of subluminous Type II-P supernovae (e.g., 2005cs, 2003gd, 1999br, 1997D)…
Massive stars undergoing iron core-collapse at the end of their evolution terminate their lives either in successful or failed supernovae (SNe). The physics of core-collapse supernovae (CCSNe) is complex, and their understanding requires…
Multi-dimensional hydrodynamic simulations of the post-bounce evolution of collapsed stellar iron cores have demonstrated that convective overturn between the stalled shock and the neutrinosphere can have an important effect on the…
We consider sterile neutrinos with rest masses ~0.2 GeV. Such sterile neutrinos could augment core collapse supernova shock energies by enhancing energy transport from the core to the vicinity of the shock front. The decay of these…
Bipolar explosion models for hypernovae (very energetic supernovae), associated with the black hole formation, are presented. The model features are as follows: (1) Fe-peak elements are ejected at high velocities to reach the surface…
When a massive star ends its life, its core collapses, forming a neutron star or black hole and producing some of the most energetic explosions in the universe. Core-collapse supernovae and long-duration gamma-ray bursts are the violent…
We perform hydrodynamical simulations of neutron-star mergers for a large sample of temperature-dependent, nuclear equations of state, and determine the threshold mass above which the merger remnant promptly collapses to form a black hole.…
Neutrinos are densely populated deep inside the core of massive stars after their gravitational collapse to produce supernova explosions and form compact stars such as neutron stars (NS) and black holes (BH). It has been considered that…
I examine a mechanism by which two fast narrow jets launched by a newly formed neutron star (NS), or a black hole (BH), at the center of a core collapse supernovae (CCSN), form two slow massive wide (SMW) jets. Such SMW jets are assumed as…
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…
The core collapse of a massive star results in the formation of a proto-neutron star (PNS). If enough material is accreted onto a PNS it will become gravitationally unstable and further collapse into a black-hole (BH). We perform a…
A large fraction of core-collapse supernovae (CCSNe), 30-50%, are expected to originate from the low-mass end of progenitors with $M_{\rm ZAMS}~= 8-12~M_\odot$. However, degeneracy effects make stellar evolution modelling of such stars…
We are monitoring 27 galaxies within 10 Mpc using the Large Binocular Telescope to search for failed supernovae (SNe), massive stars that collapse to form a black hole without a SN explosion. We present the results from the first 4 years of…
Recent developments in multi-dimensional simulations of core-collapse supernovae have considerably improved our understanding of this complex phenomenon. In addition to that, one-dimensional (1D) studies have been employed to study the…
The dynamics of galactic nuclei reflects the presence of supermassive black holes (SBHs) in many ways. Single SBHs act as sinks, destroying a mass in stars equal to their own mass in roughly one relaxation time and forcing nuclei to expand.…