Direct Evidence for an Early Reionization of the Universe?
Panagia, N.; Stern, D.; Dickinson, M.; Ferguson, H. C.; Giavalisco, M.; Mobasher, B.; Fall, S. M.; Wiklind, T.
United States
Abstract
We examine the possible reionization of the intergalactic medium by the source UDF 033238.7-274839.8 (hereafter HUDF-JD2), which was discovered in deep HST/VLT/Spitzer images obtained as part of the Great Observatories Origins Deep Survey and Hubble Ultra Deep Field projects. Mobasher et al. have identified HUDF-JD2 as a massive (~6×1011 Msolar) 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.
Based on observations obtained with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555 on observations obtained at the European Southern Observatory (ESO) using the ESO Very Large Telescope (VLT) on Cerro Paranal (Director's Discretionary Time), and on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under NASA contract 1407.