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GRB Afterglows as a New Probe of the ISM and IGM at High Redshift

Hsiao-Wen Chen·Jason X. Prochaska·Josh S. Bloom
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Abstract

We summarize results from a study of the metallicity, relative abundances, gas density, and kinematics of dense media in the host environment of two Swift bursts, GRB050730 at z=3.968 and GRB051111 at z=1.549. Both GRB hosts exhibit strong absorption features from excited Si+ and Fe+ ions, indicating an extreme ISM environment that is similar to what is found around massive stars like luminous blue variables (LBV) and Wolf-Rayet stars. The extreme ISM properties have never been observed in intervening quasar absorption line systems beyond the local universe.

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Hsiao-Wen Chen, Jason X. Prochaska, Josh S. Bloom. 2006-02-07. GRB Afterglows as a New Probe of the ISM and IGM at High Redshift. https://arxiv.org/abs/astro-ph/0602144

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