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Binary-driven hypernova (BdHN) models long gamma-ray burst (GRB) as occurring in the binary systems involving a carbon–oxygen core (CO core ) and a companion neutron star (NS) or a black hole (BH). This model, first proposed in 2012, succeeds and improves upon the fireshell model and the induced gravitational collapse (IGC) paradigm. After nearly a decade of development, the BdHN model has reached a nearly complete structure, giving explanation to all the observables of long bursts into its theoretical framework, and has given a refined classification of long GRB according to the original properties of the progenitors. In this paper, we present a summary of the BdHN model and the physical processes at work in each of the envisaged Episodes during its occurrence and lifetime, duly contextualized in the framework of GRB observations. [ABSTRACT FROM AUTHOR]

Self-interacting dark matter (SIDM) is a hypothetical form of dark matter (DM), characterized by relatively strong (compared to the weak interaction strength) self-interactions (SIs), which has been proposed to resolve a number of issues concerning tensions between simulations and observations at the galactic or smaller scales. We review here some recent developments discussed at the 14th Marcel Grossmann Meeting (MG14), paying particular attention to restrictions on the SIDM (total) cross-section from using novel observables in merging galactic structures, as well as the rôle of SIDM on the Milky Way halo and its central region. We report on some interesting particle-physics inspired SIDM models that were discussed at MG14, namely the glueball DM, and a right-handed neutrino DM (with mass of a few tens of keV, that may exist in minimal extensions of the standard model (SM)), interacting among themselves via vector bosons mediators in the dark sector. A detailed phenomenology of the latter model on galactic scales, as well as the potential role of the right handed neutrinos in alleviating some of the small-scale cosmology problems, namely the discrepancies between observations and numerical simulations within standard CDM and WDM cosmologies are reported. [ABSTRACT FROM AUTHOR]

We describe the GRB and all-sky monitor experiment (GAME) mission submitted by a large international collaboration (Italy, Germany, Czech Republic, Slovenia, Brazil) in response to the 2012 ESA call for a small mission opportunity for a launch in 2017 and presently under further investigation for subsequent opportunities. The general scientific objective is to perform measurements of key importance for GRB science and to provide the wide astrophysical community of an advanced X-ray all-sky monitoring system. The proposed payload was based on silicon drift detectors (~l-50keV), CdZnTe (CZT) detectors (~15-200keV) and crystal scintillators in phoswich (Nal/Csl) configuration (~20keV-20MeV), three well established technologies, for a total weight of ~250kg and a required power of ~240 W. Such instrumentation allows a unique, unprecedented and very powerful combination of large field of view (3-4 sr), a broad energy band extending from ~lkeV up to ~20MeV, an energy resolution as good as ~250eV in the 1-30 keV energy range, a source location accuracy of ~1 arcmin. The mission profile included a launch (e.g. by Vega) into a low Earth orbit, a baseline sky scanning mode plus pointed observations of regions of particular interest, data transmission to ground via X-band (4.8 Gb/orbit, Alcantara and Malindi ground stations), and prompt transmission of GRB/transient triggers. [ABSTRACT FROM AUTHOR]

We review recent progress in our understanding of the nature of Gamma Ray Bursts (GRBs) and in particular, of the relationship between short GRBs and long GRBs. The first example of a short GRB is described. The coincidental occurrence of a GRB with a supernova (SN) is explained within the induced gravitational collapse (IGC) paradigm, following the sequence: (1) an initial binary system consists of a compact carbon-oxygen (CO) core star and a neutron star (NS); (2) the CO core explodes as a SN, and part of the SN ejecta accretes onto the NS which reaches its critical mass and collapses to a black hole (BH) giving rise to a GRB; (3) a new NS is generated by the SN as a remnant. The observational consequences of this scenario are outlined. [ABSTRACT FROM AUTHOR]

Current research marks a clear success in identifying the moment of formation of a Black Hole of ~ IOM⊙, with the emission of a Gamma Ray Burst. This explains in terms of the 'Blackholic Energy' the source of the energy of these astrophysical systems. Their energetics up to 1054 erg, make them detectable all over our Universe. Concurrently a new problematic has been arising related to: (a) The evidence of Dark Matter in galactic halos; (b) The origin of the Super Massive Black Holes in active galactic nuclei and Quasars and (c) The purported existence of a Black Hole in the Center of our Galaxy. These three aspects of this new problematic have been traditionally approached independently. We propose an unified approach to all three of them based on a system of massive self-gravitating neutrinos in General Relativity. Perspectives of future research are presented. [ABSTRACT FROM AUTHOR]

We summarize recent progress in the formulation of a theory for white dwarfs and neutron stars taking into account the strong, weak, electromagnetic and gravitational interactions based on the general relativistic Thomas-Fermi equations of equilibrium and the Einstein-Maxwell equations. [ABSTRACT FROM AUTHOR]