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Uncertainties in the Determination of Primordial D/H

Antoinette Songaila
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Abstract

The current status of high redshift D/H measurements is discussed. I first examine whether the observations of HS1937-1009 require a low value of D/H. It is shown that the LRIS measurements of the continuum break and the high resolution Lyman series data can easily be modelled with D/H in the range 5 x 10^(-5) to 10^(-4). I then discuss measurements on weaker Lyman limit systems. A statistical treatment of 10 partial Lyman limit systems favors D/H between 5 x 10^(-5) and 2 x 10^(-4).

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Antoinette Songaila. 1997-09-30. Uncertainties in the Determination of Primordial D/H. https://arxiv.org/abs/astro-ph/9709293

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