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The very early optical afterglow of GRBs, revealing the nature of the ejecta

Y. Z. Fan·Bing Zhang·D. M. Wei
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Abstract

We show that if the GRB ejecta itself is magnetized or neutron-rich, the very early afterglow of GRBs is very different from that powered by a pure ion fireball. In the Swift era, with the well monitored early afterglow data, we can potentially diagnose the ejecta composition and reveal the nature of the central GRB engine.

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Y. Z. Fan, Bing Zhang, D. M. Wei. 2005-03-09. The very early optical afterglow of GRBs, revealing the nature of the ejecta. https://arxiv.org/abs/astro-ph/0503194

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