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arXiv · astro-ph/9906432

Gamma Ray Burst and Soft Gamma Repeaters. Spinning, Precessing Gamma Jets

Abstract

Gamma Ray Bursts as recent GRB990123 and GRB990510 are observed to occur in cosmic volumes with a corresponding output reaching, for isotropic explosions, energies as large as two solar masses annihilation. These energies are underestimated because of the neglected role of comparable ejected neutrinos bursts. These extreme power cannot be explained with any standard spherically symmetric Fireball model. A too heavy black hole or Star would be unable to coexist with the shortest millisecond time structure of Gamma ray Burst. Beaming of the gamma radiation may overcome the energy puzzle. However any mild explosive beam $(\Omega > 10^{-2})$ should not solve the jet containment at those disruptive energies. Only extreme beaming $(\Omega < 10^{-8})$, by a slow decaying, but long-lived precessing jet, it may coexist with characteristic Supernova energies, apparent GRBs output, statistics as well as their connection with older and nearer SGRs relics.

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BibTeXRIS

Daniele Fargion. 1999-06-28. Gamma Ray Burst and Soft Gamma Repeaters. Spinning, Precessing Gamma Jets. https://arxiv.org/abs/astro-ph/9906432

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