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arXiv · astro-ph/0307348

Rebrightening in GRBs by Precessing Jet

Abstract

A clear gamma polarization in the gamma signals from GRB021206 probes the presence of a very thin collimated jet (opening angle Deltaθ< 0.6^o, (DeltaΩ)Ω< 2.5 10^-5) in Gamma Ray Burst, GRBs. The last and well proved GRB030329/SN2003dh time and space coincidence confirms definitively the earliest GRB980425/SN1998bw connection among GRB and Supernova. The apparent extreme GRBs luminosity is just the extreme beamed blazing gamma Jet observed in axis during a Supernova birth. The late relic GRBs sources may be found in compact SNRs core, as NS or BH jets; at much later epoch, their lower power gamma jets may be within detectability only from nearby galactic distances, as Soft Gamma Repeaters (SGRs) or anomalous X-ray Pulsars, AXPs. This common Jet nature explain some connection between GRBs and SGRs spectra. The geometrical multi-precessing beaming and their reappearance to the observer may explain the puzzling presence of X-Ray precursors in GRBs as well as in SGRs. A mysterious re-brightening afterglows observed in early and late GRB 030329 optical transient, like in the 27 August 1998 and 18 April 2001 SGR 1900+14 events, might be understood as the damped oscillatory imprint left by such a multi-precessing gamma-X-Optical and Radio Jet.

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BibTeXRIS

D. Fargion. 2003-07-18. Rebrightening in GRBs by Precessing Jet. https://arxiv.org/abs/astro-ph/0307348

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