A Catalog of Absorption Lines in Eight HST/STIS E230M 1.0 < z < 1.7 Quasar Spectra

TL;DR

This paper presents a detailed catalog of absorption lines in high-quality HST/STIS quasar spectra, identifying 56 metal-line systems and analyzing their properties to aid future astrophysical research.

Contribution

It provides the first comprehensive catalog of absorption features in eight high signal-to-noise quasar spectra, including detailed line identifications and measurements.

Findings

1/4 - 1/3 of features in the Lya forest are metal lines

High ionization transitions like O VI and C IV are very common

Low ionization lines are detected in about half of the systems

Abstract

We have produced a catalog 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 among the HST/STIS spectra obtained with the E230M grating. We identify 56 metal-line systems toward 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 Lya forest region, redward of the incidence of the Lyb forest, are metal lines. High ionization transitions are common. We see both O VI and C IV in 88 - 90% of the metal-line systems for which the spectra cover the expected wavelength. Si III is seen in 58%, while low ionization absorption in C II, Si II, and/or Al II is detected in 50% of the systems for which they are covered. This catalog will facilitate future studies of the Lya forest and of metal-line systems of various types.