Energetic GRBs-SNe in the Induced Gravitational Collapse scenario : the case of the prototype GRB 090618

Author: Luca Izzo

Abstract: A novel concept has recently been proposed for explaining the temporal coincidence of some gamma ray bursts (GRBs) with an associated supernova (SN) in terms of the gravitational collapse of a neutron star (NS) onto a black hole (BH), induced by a type Ib/c SN explosion. We present the scenario and the results of the IGC model applied to the case of GRB 090618, one of the most energetic and near GRB ever observed. We have calculated the accretion rate and total accreted mass onto an NS from an SN Ib/c that originated from a companion evolved star, showing that the NS reaches the critical mass in a few seconds and undergoes gravitational collapse onto a BH, leading to the emission of a GRB. Some considerations about cosmological implications and progenitors will be discussed.

The existence of 4 episodes are outlined. The possibility of using this result to infer the presence of a SN event is discussed.