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Early afterglows as probes for the reionization epoch

Davide Lazzati·Gabriele Ghisellini·Francesco Haardt·Alberto Fernandez-Soto
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Abstract

The nature of Gamma-Ray Burst progenitors is still a debated issue, but consensus is growing on the association of GRBs with massive stars. Furthermore, current models for the reionization of the universe consider massive Pop--III stars as the sources of the ionizing photons. There could then be a natural link between GRBs and reionization. The reionization epoch can be measured through prompt IR spectral observations of high redshift GRBs. For this, GRBs are better than quasars: they produce a smaller HII region even if they are much brighter than quasars (but for a much shorter time) and then, contrary to quasars, they do not modify the absorption properties of the surrounding IGM.

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Davide Lazzati, Gabriele Ghisellini, Francesco Haardt, Alberto Fernandez-Soto. 2001-03-20. Early afterglows as probes for the reionization epoch. https://doi.org/10.1007/10853853_52

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