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تسجيل مستخدم جديدDirect evidence for an early reionization of the Universe?
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N. Panagia
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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 ($sim6times10^{11}M_odot$) 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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