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The Damping Wing of the Gunn-Peterson Absorption and Lyman-Alpha Emitters in the Pre-Reionization Era

Nickolay Y. Gnedin·Francisco Prada
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Abstract

We use a numerical simulation of cosmological reionization to estimate the likelihood of detecting Lyman-alpha emitting galaxies during the pre-reionization era. We show that it is possible to find galaxies even at z~9 that are barely affected by the dumping wing of the Gunn-Peterson absorption from the neutral IGM outside of their HII regions. The damping wing becomes rapidly more significant at z>9, but even at z>10 is it not inconceivable (although quite hard) to see a Lyman-alpha emission line from a star-forming galaxy.

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Nickolay Y. Gnedin, Francisco Prada. 2004-03-15. The Damping Wing of the Gunn-Peterson Absorption and Lyman-Alpha Emitters in the Pre-Reionization Era. https://doi.org/10.1086/422390

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