High resolution observations of the QSO BR1202-0725: deuterium and ionic abundances at redshifts above z=4

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 Ly\alpha system with an HI column density of 3.1 \times 10^{20} 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 \times 10^{16} 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 1.5\,10^{-4}. Because this cloud is metal rich at least some of the cloud gas has been processed after the beginning of the Universe