Related papers: Supernovae, Jets, and Collapsars
Highly relativistic jets are a key element of current gamma-ray burst models, where the jet kinetic energy is converted to radiation energy at optically thin shocks. High-energy neutrinos are also expected, from interactions of protons…
We perform two-dimensional, axisymmetric, magnetohydrodynamic simulations of the collapse of a rotating star of 40 Msun and in the light of the collapsar model of gamma-ray burst. Considering two distributions of angular momentum, up to…
The nuclei of most normal galaxies contain supermassive black holes, which can accrete gas through a disk and become active. These Active Galactic Nuclei, AGN, can form jets which are observed on scales from AU to Mpc and from meter…
Recent observations suggest that gamma ray bursts (GRBs) and their afterglows are produced by highly relativistic jets emitted in supernova explosions. We have proposed that the result of the event is not just a compact object plus the…
A common consequence of accretion onto black holes is the formation of powerful, relativistic jets that escape the system. In the case of supermassive black holes at the centres of galaxies this has been known for decades, but for…
We study the physics behind the neutrino-driven mechanism for gamma-ray bursts and hypernovae, deriving the critical density at which these outbursts occur in the collapsar model. The agreement between this derivation and results from past…
We suggest that an extreme Kerr black hole with a mass $\sim 10^6M_\odot$, a dimensionless angular momentum $A\sim 1$ and a marginal stable orbital radius $r_{ms}\sim 3r_s\sim 10^{12}M_6 cm$ located in a normal galaxy, may produced a…
Long-duration gamma-ray bursts (GRBs) are thought to be connected to luminous and energetic supernovae (SNe), called hypernovae (HNe), resulting from the black-hole (BH) forming collapse of massive stars. For recent nearby GRBs~060505 and…
We propose a new model of Fast Radio Bursts (FRBs) based on stellar mass black hole-massive star binaries. We argue that the inhomogeneity of the circumstellar materials or/and the time varying wind activities of the stellar companion will…
Cosmological GRBs are discussed with an emphasis on their plausible connection with black holes. GRBs can be triggered by collapse of stellar-mass objects that leads to formation of a black hole and a transient debris disk with a huge…
We consider a jet-disk symbiosis model to explain Gamma Ray Bursts and their afterglows. It is proposed that GRBs are created inside a pre-existing jet from a neutron star in a binary system which collapses to a black hole due to accretion.…
Supernovae connected with long-duration gamma-ray bursts (GRBs) are hyper-energetic explosion resulting from the collapse of very massive stars (about 40Mo, where Mo is the mass of the Sun) stripped of their outher hydrogen and helium…
Black-hole driven relativistic astrophysical jets, such as blazars and gamma-ray bursts (GRBs), are powerful sources of electromagnetic radiation. Their emission is powered by some energy dissipation and particle acceleration mechanism…
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…
Short gamma-ray bursts (sGRBs) are thought to be produced by binary NS mergers. While a sGRB requires a relativistic jet to break out of ejecta, the jet may be choked and fails to produce a successful sGRB. We propose a "delayed breakout"…
The core collapse of massive, rapidly-rotating stars are thought to be the progenitors of long-duration gamma-ray bursts (GRB) and their associated hyper-energetic supernovae (SNe). At early times after the collapse, relatively low angular…
I constrain a possible supernova origin for gamma-ray bursts by modeling the dynamical interaction between a relativistic jet and a stellar envelope surrounding it. The delay in observer's time introduced by the jet traversing the envelope…
We explore fallback accretion onto newly born magnetars during the supernova of massive stars. Strong magnetic fields (~10^{15} G) and short spin periods (~1-10 ms) have an important influence on how the magnetar interacts with the…
Whether a short gamma-ray burst (GRB) is caused by a black hole (BH) or a neutron star (NS) after the merger of a NS binary is a crucial problem. We propose a BH model that explains short GRBs with long-lasting activities such as extended…
Heavy nuclei such as nickel-56 are synthesized in a wide range of core-collapse supernovae (CCSN), including energetic supernovae associated with gamma-ray bursts (GRBs). Recent studies suggest that jet-like outflows are a common feature of…