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Reconsidering the origin of the X-ray emission lines in GRB 011211

Fabrizio Tavecchio·Gabriele Ghisellini·Davide Lazzati
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Abstract

We reanalyze the XMM--Newton data of GRB 011211 showing that the spectral features, interpreted by Reeves et al. (2002, 2003) as due thermal emission from a collisionally ionized plasma, can be also reproduced by a reflection model (with ionization parameter $ξ\sim 10^2$). We discuss the implications of this interpretation, estimating the total mass required in the simplified case of a funnel geometry. We conclude that a moderate clumping of the reprocessing material (corresponding to a filling factor of the order of $f\sim 10^{-3}$) is required. Finally we show that, if this interpretation is correct, a bright quasi--thermal component is expected in the optical--UV band (containing about 90% of the luminosity of the illuminating continuum), whose presence can be used to test the reflection model.

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Fabrizio Tavecchio, Gabriele Ghisellini, Davide Lazzati. 2003-10-10. Reconsidering the origin of the X-ray emission lines in GRB 011211. https://doi.org/10.1051/0004-6361%3A20034626

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