APM z ~ 4 survey : distribution and evolution of high column density H I absorbers
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منابع مشابه
ar X iv : a st ro - p h / 95 03 08 9 v 1 2 4 M ar 1 99 5 High Redshift Lyman Limit and Damped Lyman - Alpha Absorbers
To appear in " ESO Workshop on QSO Absorption Lines " Preprint: astro-ph/yymmddd Abstract We have obtained high signal:to:noise optical spectroscopy at 5 ˚ A resolution of 27 quasars from the APM z>4 quasar survey. The spectra have been analyzed to create new samples of high redshift Lyman-limit and damped Lyman-α absorbers. These data have been combined with published data sets in a study of t...
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