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Direct evidence for an early reionization of the Universe?

N. Panagia·S. M. Fall·B. Mobasher·M. Dickinson·H. C. Ferguson·M. Giavalisco·D. Stern·T. Wiklind
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Abstract

We examine the possible reionization of the intergalactic medium (IGM) by the source UDF033238.7-274839.8 (hereafter HUDF-JD2), which was discovered in deep {\it HST}/VLT/{\it Spitzer} images obtained as part of the Great Observatory Origins Deep Survey and {\it Hubble} Ultra-Deep Field projects. Mobasher et al (2005) have identified HUDF-JD2 as a massive ($\sim6\times10^{11}M_\odot$) post-starburst galaxy at redshift z$\gtrsim6.5$. 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$\approx 15 \pm5$.

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N. Panagia, S. M. Fall, B. Mobasher, M. Dickinson, H. C. Ferguson, M. Giavalisco, D. Stern, T. Wiklind. 2005-09-20. Direct evidence for an early reionization of the Universe?. https://doi.org/10.1086/498094

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