Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z~6 Quasars II: A Sample of 19 Quasars

  title={Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z~6 Quasars II: A Sample of 19 Quasars},
  author={Xiaohui Fan and Michael A. Strauss and Robert H. Becker and Richard L. White and James E. Gunn and Gillian R. Knapp and Gordon T. Richards and Donald P. Schneider and Jonathan V. Brinkmann and Masataka Fukugita},
  journal={The Astronomical Journal},
We study the evolution of the ionization state of the intergalactic medium (IGM) at the end of the reionization epoch using moderate resolution spectra of a sample of nineteen quasars at 5.74 5.7: the GP optical depth evolution changes from {tau}{sub GP}{sup eff} {approx} (1 + z){sup 4.3} to (1 + z){sup {approx}> 11}, and the average length of dark gaps with {tau} > 3.5 increases from 80 comoving Mpc. The dispersion of IGM properties along different lines of sight also increases rapidly… Expand
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