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arXiv · 0910.2273

An apparent GRBs evolution around us or a sampling of thin GRB beaming jets?

Abstract

The gamma ray burst apparent average isotropic power versus their red-shift of all known GRB (Sept.2009) is reported. It calls for an unrealistic Gamma Ray Burst Evolution around us or it just probe the need of a very thin gamma precession-jet model. These precessing and spinning jet are originated by Inverse Compton and-or Synchrotron Radiation at pulsars or micro-quasars sources, by ultra-relativistic electrons. These Jets are most powerful at Supernova birth, blazing, once on axis, to us and flashing GRB detector. The trembling of the thin jet (spinning, precessing, bent by magnetic fields) explains naturally the observed erratic multi-explosive structure of different GRBs and its rare re-brightening. The jets are precessing (by binary companion or inner disk asymmetry) and decaying by power law on time scales to a few hours. GRB blazing occurs inside the observer cone of view only a seconds duration times; because relativistic synchrotron (or IC) laws the jet angle is thinner in gamma but wider in X band. Its apparent brightening is so well correlated with its hardness (The Amati correlation). This explain the wider and longer X GRB afterglow duration and the (not so much) rare presence of X-ray precursors well before the apparent main GRB explosion. The jet lepton maybe originated by an inner primary hadron core (as well as pions and muons secondary Jets). The EGRET, AGILE and Fermi few hardest and late GeV gamma might be PeV neutron beta decay in flight observed in-axis under a relativistic shrinkage.

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D. Fargion, D. D'Armiento. 2009-10-13. An apparent GRBs evolution around us or a sampling of thin GRB beaming jets?. https://arxiv.org/abs/0910.2273

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