Induced gravitational collapse, binary-driven hypernovae, long gamma-ray bursts and their connection with short gamma-ray bursts

by Prof. Jorge Rueda (ICRANeT, Roma)

Hans Bethe Meeting Room (TIFPA)

Hans Bethe Meeting Room


Via Sommarive, 14 - Trento

The multiwavelength analysis of gamma-ray bursts (GRBs) data; the gamma-rays in the prompt, the X-rays in the early and late afterglow, as well as the presence or absence of GeV emission, points to an increasing observational evidence of their separation in different GRB subclasses, each one with specific energy release, spectra, duration, etc, and all of them originating in binaries composed of carbon-oxygen cores, neutron stars, black holes, and white dwarfs. 

I shall focus here on the salient features of the specific class of binary-driven hypernovae (BdHNe) within the induced gravitational collapse (IGC) scenario. BdHNe explain the long GRBs.  The supernova (SN) explosion of a carbon-oxygen core (CO-core) onto a neutron star (NS) companion triggers a hypercritical, i.e. highly super-Eddington accretion process onto the NS owing to a copious emission of neutrinos. Depending on the binary parameters the NS can become a more massive NS or reach the critical and collapses forming a black hole. I summarize the series of results on this topic starting from the first analytic estimates in 2012 all the way up to the most recent three-dimensional (3D) smoothed-particle-hydrodynamics (SPH) numerical simulations in 2018. In particular, it is unveiled a new SN ejecta morphology, highly asymmetric, acquired by binary interaction and leading to well-defined, observable signatures in the gamma- and X-rays emission of long GRBs. Finally, based on these results the interconnection between the long and short GRBs is addressed.