1108.0638 (Daniele Fargion)
Daniele Fargion
Gamma Ray Burst sources are apparently evolving around us in a harder and brighter samples at far and far redshift. The average output may range from a near Supernova (nearest events) output to a billion time that power for most distant events. Such a tuned evolution around us is not an anti-copernican signature. It is a clear imprint of a off-axis (nearest sources) beaming versus a rarest in-axis blazing (far redshift sources) by a thin relativistic beam (Lorentz factor up ten thousand or above, corresponding to micro-nano steradian solid angle). The main consequence is the rarer and rarer presences of hardest gamma events (hundreds MeV, GeVs, tens GeVs), nearly one over a twenty, partially opaque by IR-gamma cut-off, observed with difficulty at largest redshift inside their thinner beamed jets. For this reason these rarest tens GeV beamed events, even observed by EGRET and Fermi, are hardly seen at hundred GeV by Cherenkov telescope (Magic,Hess,Veritas) on Earth. For the same reason and because tens GeV neutrino energy is below Icecube thresholds (threshold above hundreds GeV) we have not been observed yet a neutrino GRB. However if the GRBs primaries contains tens GeV neutrino traces (at comparable GRB gamma rate) their presence may rise in few years at Deep Core (a more dense array inside ICECUBE) detector whose lower threshold, ranges just one or few tens GeV energy. Moreover the very recent X ray persistent GRB110328, whose understanding was first associated to a cannibal star AGN eating, but now evolved to a cannibal AGN feeding beamed jet, it is, more naturally consistent to our thin jet GRB (by few solar mass compact source, not any AGN) spinning, precessing and blazing whose geometry is partially aligned and stable (than other GRBs) to us: its decay law and its average output is fully consistent with our earliest proposals.
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http://arxiv.org/abs/1108.0638
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