Quasar absorption studies

We propose to exploit the unprecedent troughtput of XMMNewton toperform a systematic study of a sample of quasars in which previousless sensitive observations found evidences for Xray absorption. The main goals are: 1 measure redshift and column density of the Xrayabsorbers; 2 assess whether absorption at the quasar redshift occurspreferentially in radioloud objects; 3 test the correlation betweenabsortion and redshift suggested by ROSAT and ASCA data; 4 constrainthe absorber ionization status and metallicity; 5 constrain theabsorber dust content and composition through the comparison betweenthe amount of Xray absorption and optical dust extinction. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]