Physical Sciences and Mathematics Commons^™

The Observability Of Metal Lines Associated With The Ly Alpha Forest, U Hellsten, L Hernquist, N Katz, Dh Weinberg

Astronomy Department Faculty Publication Series

We develop a prescription for characterizing the strengths of metal lines associated with Lyα forest absorbers (LYFAs) of a given neutral hydrogen column density N_{H I} and metallicity [O/H]. This line observability index (LOX) is line specific and translates, for weak lines, into a measure of the equivalent width. It can be evaluated quickly for thousands of transitions within the framework of a given model of the Lyα forest, providing a ranking of the absorption lines in terms of their strengths and enabling model builders to select the lines that deserve more detailed consideration, i.e., those that should be …