High Resolution Observations of the QSO BR1202-0725: Deuterium and Ionic Abundances at Redshifts Above z=4

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We present results from 12 km/s resolution echelle spectroscopy of the bright z=4.694 QSO BR1202-0725. A preliminary analysis shows that high metallicity narrow line absorption clouds are present up to the redshift of the quasar. A damped Lyα system with an HI column density of 3.1 × 10²⁰ cm⁻² at z=4.383 has an [O/H] ratio that is about 0.01 solar, while another absorption system with an HI column density of 5.0 × 10¹⁶ cm⁻² at z=4.672, may have an O/H ratio that is twice solar. An upper limit, or the possible detection of deuterium in this absorption cloud gives a D/H ratio of about 1.510⁻⁴. Because this cloud is metal rich at least some of the cloud gas has been processed after the beginning of the Universe.