The metal systems in Q0000--2619 at high resolution

Abstract

We have obtained high, 11 and 14 \kms, and medium, 40 and 53 \kms, resolution spectra of the $z_{em} = 4.11$ quasar Q0000--2619 covering the range 4400 Å to 9265 Å. We identify nine metal absorption systems, of which four were previously known. A fifth previously suggested system at $z_{abs} \approx 3.409$ (Turnshek et al~ 1991) is ruled out by our data. Two of the eight systems for which the \lya~ line is in the observable range have a damped \lya~ line. Six of the nine systems show evidence for complex sub--component structure. At our resolution and S/N we identify a total of 21 sub--components in the nine systems. Five of the nine systems (11 of the 21 components) fall within the $\pm 5000$ \kms~ range of the emission redshift, and are hence classified as \zae~ absorbers. For the two damped systems we find metal abundances of $\leq 1$% and $\leq 8$% of solar values at redshifts of 3.0541 and 3.3901 respectively. These upper limits are consistent with what would be expected from previous determinations at lower redshifts, and our data are hence compatible with earlier conclusions that no evidence is yet found for chemical evolution of intervening damped and Lyman limit absorbers. For the \zae~ systems we found indications of metallicities comparable to, and even in excess of solar values. These much higher values compared to the damped systems, are in favour of the intrinsic hypothesis for these systems.