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A High Deuterium Abundance at z=0.7; Evidence for Cosmic Inhomogeneity?

J. K. Webb·R. F. Carswell·K. M. Lanzetta·R. Ferlet·M. Lemoine·A. Vidal-Madjar
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Abstract

Recent HST/GHRS observations of the z = 0.7010 absorber toward the QSO 1718+4807 (selected because of apparently ideal characteristics for measuring D/H) yield a D/H significantly higher D/H than some recent high-redshift measurements. Our analysis indicates D/H}= 1.8 - 2.5 x 10^{-4}. This may indicate a cosmological inhomogeneity in the deuterium abundance of at least a factor of ten.

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J. K. Webb, R. F. Carswell, K. M. Lanzetta, R. Ferlet, M. Lemoine, A. Vidal-Madjar. 1997-10-09. A High Deuterium Abundance at z=0.7; Evidence for Cosmic Inhomogeneity?. https://arxiv.org/abs/astro-ph/9710089

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