PENACCHIONI , A.v.

Theoretical and observational evidences for a two-fold classification of short bursts have been recently obtained: (1) short gamma-ray flashes (S-GRFs), with isotropic energy ${E}_{\mathrm{iso}}\lt {10}^{52}$ erg and no black hole (BH) formation, and (2) authentic short gamma-ray bursts (S-GRBs), with isotropic energy ${E}_{\mathrm{iso}}\gt...

It has previously been discovered that there is a universal power-law behavior exhibited by the late X-ray emission (LXRE) of a "golden sample" of six long energetic GRBs, when observed in the rest frame of the source. This remarkable feature, independent of the different isotropic energy (E (iso)) of each GRB, has been used to estimate the...

In a series of recent publications, scientists from ICRANet, led by professor Remo Ruffini, have reached a novel comprehensive picture of gamma-ray bursts (GRBs) thanks to their development of a series of new theoretical approaches. Among those, the induced gravitational collapse (IGC) paradigm explains a class of energetic, long-duration GRBs...

For short gamma-ray bursts (GRBs), double neutron star (NS) mergers are traditionally adopted as progenitors. We propose a classification of short bursts into two sub-classes: short gamma-ray flashes (S-GRFs) with isotropic energy Eiso ≲ 1052 erg and rest-frame spectral peak energy Ep,i ≲ 2 MeV, when the merger leads to a very massive NS (MNS),...

Our concept of induced gravitational collapse (IGC paradigm) starting from a supernova occurring with a companion neutron star, has unlocked the understanding of seven different families of gamma ray bursts (GRBs), indicating a path for the formation of black holes in the universe. An authentic laboratory of relativistic astrophysics has been...

We analyze the early X-ray flares in the GRB "flare–plateau–afterglow" (FPA) phase observed by Swift-XRT. The FPA occurs only in one of the seven GRB subclasses: the binary-driven hypernovae (BdHNe). This subclass consists of long GRBs with a carbon–oxygen core and a neutron star (NS) binary companion as progenitors. The hypercritical accretion...

Short and long-duration gamma-ray bursts (GRBs) have been recently sub-classified into seven families according to the binary nature of their progenitors. For short GRBs, mergers of neutron star binaries (NS–NS) or neutron star-black hole binaries (NS-BH) are proposed. For long GRBs, the induced gravitational collapse (IGC) paradigm proposes a...