Surveys for z > 3 Damped Lyα Absorption Systems: The Evolution of Neutral Gas

  title={Surveys for z > 3 Damped Ly$\alpha$ Absorption Systems: The Evolution of Neutral Gas},
  author={L. J. Storrie-Lombardi and Arthur M. Wolfe},
  journal={The Astrophysical Journal},
  pages={552 - 576}
We have completed spectroscopic observations using LRIS on the Keck 1 telescope of 30 very high redshift quasars, 11 selected for the presence of damped Lyα absorption systems and 19 with redshifts z > 3.5 not previously surveyed for absorption systems. We have surveyed an additional 10 QSOs with the Lick 120'' and the Anglo-Australian Telescope. We have combined these with previous data, resulting in a statistical sample of 646 QSOs and 85 damped Lyα absorbers with column densities N ≥ 2… 

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