Direct Evidence for an Early Reionization of the Universe?
نویسندگان
چکیده
We examine the possible reionization of the intergalactic medium (IGM) by the source UDF033238.7274839.8 (hereafter HUDF-JD2), which was discovered in deep HST/VLT/Spitzer images obtained as part of the Great Observatory Origins Deep Survey and Hubble Ultra-Deep Field projects. Mobasher et al. (2005) have identified HUDF-JD2 as a massive (∼ 6 × 10M⊙) post-starburst galaxy at redshift z& 6.5. We find that HUDF-JD2 may be capable of reionizing its surrounding region of the Universe, starting the process at a redshift as high as z≈ 15± 5. Subject headings: galaxies: evolution — galaxies: high-redshift — galaxies: intergalactic medium — galaxy: individual (HUDF-JD2) — cosmology: observations — cosmology: theory — cosmology: early universe
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تاریخ انتشار 2008