Effective Screening due to Minihalos During the Epoch of Reionization
نویسندگان
چکیده
We show that the gaseous halos of collapsed objects introduce a substantial cumulative opacity to ionizing radiation, even after the smoothly distributed hydrogen in the intergalactic medium has been fully reionized. This opacity causes a delay of ∆z & 1 in redshift between the time of the overlap of ionized bubbles in the intergalactic medium and the lifting of complete Gunn-Peterson Lyα absorption. The minihalos responsible for this screening effect are not resolved by existing numerical simulations of reionization.
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