Deuterium toward Quasar Q0014+813

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Abstract
We present new Keck telescope spectra of the first QSO claimed to show deuterium absorption: Q0014+813. Improved signal on the Lyman series absorption lines gives more accurate information on the hydrogen absorption and more accurate predictions for the position, width, and shape of the associated deuterium absorption. There are three reasons why the absorption line near the expected position of D in the absorption system at zabs = 3.32 is not primarily D: (1) it is 17 ± 1 km s-1 from the expected position, (2) it is too wide, and (3) it does not have the expected profile, which is given by the H I lines. This absorption can be explained by a single H Lyα line at a different redshift. Any absorption from D would be completely blended with this additional H absorption. We find 0 < D/H < 35 × 10-5 for this absorber which once offered the best evidence for a high primordial value of D/H. In a second absorption system at zabs = 2.80 we again find that H alone can explain the spectrum, without any D. Deuterium has been seen and measured in only two QSOs (Q1937-1009 and Q1009+2956) and both give a low value of D/H = 3.4 × 10-5. Several other QSOs give upper limits which are less sensitive.