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arXiv · 1605.00177

Solving the missing GRB neutrino and GRB-SN puzzles

Daniele Fargion·Pietro Oliva
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Abstract

Every GRB model where the progenitor is assumed to be a highly relativistic hadronic jet whose pions, muons and electron pair secondaries are feeding the gamma jets engine, necessarily (except for very fine-tuned cases) leads to a high average neutrino over photon radiant exposure (radiance), a ratio well above unity, though the present observed average IceCube neutrino radiance is at most comparable to the gamma in the GRB one. Therefore no hadronic GRB, fireball or hadronic thin precessing jet, escaping exploding star in tunneled or penetrarting beam, can fit the actual observations. A new model is shown here, based on a purely electronic progenitor jet, fed by neutrons (and relics) stripped from a neutron star (NS) by tidal forces of a black hole or NS companion, showering into a gamma jet. Such thin precessing spinning jets explain unsolved puzzles such as the existence of the X-ray precursor in many GRBs. The present pure electron jet model, disentangling gamma and (absent) neutrinos, explains naturally why there is no gamma GRB correlates with any simultaneous TeV IceCube astrophysical neutrinos. Rare unstable NS companion stages while feeding the jet may lead to an explosion simulating a SN event. Recent IceCube-160731A highest energy muon neutrino event with absent X-gamma traces confirms the present model expectations.

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Daniele Fargion, Pietro Oliva. 2016-08-09. Solving the missing GRB neutrino and GRB-SN puzzles. https://doi.org/10.1016/j.nuclphysbps.2018.07.035

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