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Redshift determination in the X-ray band of gamma-ray bursts

G. Ghisellini·F. Haardt·S. Campana·D. Lazzati·S. Covino
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Abstract

If gamma-ray bursts originate in dense stellar forming regions, the interstellar material can imprint detectable absorption features on the observed X-ray spectrum. Such features can be detected by existing and planned X-ray satellites, as long as the X-ray afterglow is observed after a few minutes from the burst. If the column density of the interstellar material exceeds ~10^{23} cm^{-2} there exists the possibility to detect the K_alpha fluorescent iron line, which should be visible for more than one year, long after the X-ray afterglow continuum has faded away. Detection of these X-ray features will make possible the determination of the redshift of gamma-ray bursts even when their optical afterglow is severely dimmed by extinction.

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G. Ghisellini, F. Haardt, S. Campana, D. Lazzati, S. Covino. 1998-08-14. Redshift determination in the X-ray band of gamma-ray bursts. https://doi.org/10.1086/307182

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