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Soft X-ray emission lines in the early afterglow of gamma-ray bursts

Davide Lazzati·Enrico Ramirez-Ruiz·Martin J. Rees
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Abstract

We compute the luminosity of K_alpha emission lines produced by astrophysically abundant elements in the soft X-ray spectra of the early afterglow of gamma-ray bursts. We find that the detection of these lines can be a diagnostic for the geometrical set-up of the reprocessing material. In particular we can distinguish between a ``geometry dominated'' model, in which the line emission is coming from an extended region and its duration arises from light-travel-time effects and an ``engine dominated'' model, where the line emitting gas is in a smaller region, irradiated for a longer period. These lines therefore offer clues to the dynamics and time-scale of the explosion leading to a gamma-ray burst.

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Davide Lazzati, Enrico Ramirez-Ruiz, Martin J. Rees. 2002-04-29. Soft X-ray emission lines in the early afterglow of gamma-ray bursts. https://doi.org/10.1086/341448

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