Fireballs with a Neutron Component

Andrei M. Beloborodov

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arXiv · astro-ph/0302057

Fireballs with a Neutron Component

Andrei M. Beloborodov

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Abstract

Standard GRB fireballs must carry free neutrons. This crucially changes the mechanism of fireball deceleration by an external medium. As the ion fireball decelerates, the coasting neutrons form a leading front. They gradually decay, leaving behind a relativistic trail of decay products mixed with the ambient medium. The ion fireball sweeps up the trail and drives a shock wave in it. Thus, observed afterglow emission is produced in the neutron trail. The impact of neutrons turns off at 10^{17}cm from the explosion center, and here a spectral transition is expected in GRB afterglows. Absence of neutron signatures would point to absence of baryons and a dominant Poynting flux in the fireballs.

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Andrei M. Beloborodov. 2003-02-04. Fireballs with a Neutron Component. https://arxiv.org/abs/astro-ph/0302057

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