We have produced a catalogue of line identifications and equivalent width measurements for all absorption features in eight ultraviolet echelle quasar spectra. These spectra were selected as having the highest signal-to-noise ratio among the Hubble Space Telescope/STIS spectra obtained with the E230M grating. We identify 56 metal-line systems towards the eight quasars, and present plots of detected transitions, aligned in velocity space. We found that about 1/4-1/3 of the features in the Lyα forest region, redward of the incidence of the Lyβ forest, are metal lines. High-ionization transitions are common. At the redshift range we study, z < 1.7, we see both O vi and C iv in 88-90 per cent of the metal-line systems for which the spectra cover the expected wavelength. Si iii is seen in 58 per cent, while low-ionization absorption in C ii, Si ii and/or Al ii is detected in 50 per cent of the systems for which they are covered. This catalogue will facilitate future studies of the Lyα forest and of metal-line systems of various types.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science