Advances in the Study of the IGM at High Redshifts with the VLT High-Resolution Spectrograph UVES

Abstract.

UVES, the VLT echelle spectrograph, has started regular operation at the Kueyen 8.2m telescope (VLT UT2) on April 1st, 2000. The instrument offers unique performance as of efficiency and resolving power over the spectral range from the atmospheric cutoff in the UV to 1μm. More than 150 hours of scientific observations obtained during the commissioning of the instrument have been made publicly available through the VLT archive. Two examples from that data set are shown to illustrate the limiting capability of the instrument in the study of absorption lines in quasar spectra: the observations of the Ly $\alpha$ forest at z $\sim 2$ and the detection of metal lines in one Damped Lyman $\alpha$ system at very high redshift (z =4.466, the highest redshift DLA for which a detailed study has ever been made).