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Delayed Gev Emission from Cosmological Gamma-Ray Bursts : Impact of a Relativistic Wind on External Matter

P. Meszaros·M. J. Rees
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Abstract

Sudden collapse of a compact object, or coalescence of a compact binary, can generate an unsteady relativistic wind that lasts for a few seconds. The wind is likely to carry a high magnetic field; and its Lorentz factor depends on the extent to which it is 'loaded' with baryons. If the Lorentz factor is $\sim 100$, internal dissipation and shocks in this wind produce a non-thermal gamma-ray burst, detectable in the range $0.1\MeV \siml E_γ\siml 0.1-1\GeV$ out to cosmological distances. The cooled wind ejecta would subsequently be decelerated by the external medium. The resultant blast wave and reverse shock can then give rise to a second burst component, mainly detectable in the GeV range, with a time delay relative to the MeV burst ranging from minutes to hours.

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P. Meszaros, M. J. Rees. 1994-04-22. Delayed Gev Emission from Cosmological Gamma-Ray Bursts : Impact of a Relativistic Wind on External Matter. https://doi.org/10.1093/mnras%2F269.1.l41

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