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arXiv · 0901.2128

Naked-eye optical flash from GRB 080319B: Tracing the decaying neutrons in the outflow

Yi-Zhong Fan·Bing Zhang·Da-Ming Wei
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Abstract

For an unsteady baryonic gamma-ray burst (GRB) outflow, the fast and slow proton shells collide with each other and produce energetic soft gamma-ray emission. If the outflow has a significant neutron component, the ultra-relativistic neutrons initially expand freely until decaying at a larger radius. The late time proton shells ejected from the GRB central engine, after powering the regular internal shocks, will sweep these $β-$decay products and give rise to very bright UV/optical emission. The naked-eye optical flash from GRB 080319B, an energetic explosion in the distant universe, can be well explained in this way.

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Yi-Zhong Fan, Bing Zhang, Da-Ming Wei. 2009-01-14. Naked-eye optical flash from GRB 080319B: Tracing the decaying neutrons in the outflow. https://doi.org/10.1103/physrevd.79.021301

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