|
|
Paper: |
Abundances in a Low-z Lyman Limit System in Front of PHL 1811, as Determined from FUSE and STIS Spectra |
Volume: |
348, Astrophysics in the Far Ultraviolet: Five Years of Discovery with FUSE |
Page: |
351 |
Authors: |
Jenkins, E.B.; Bowen, D.V.; Tripp, T.M.; Sembach, K.R. |
Abstract: |
PHL 1811 is an exceptionally bright quasar, and its sight line penetrates a group of galaxies at z = 0.075. From an exploratory FUSE spectrum, we could identify 7 intervening extragalactic absorption systems, four of which arise from the group, and of those four, one is a Lyman Limit system at z = 0.080923. We identified two S0 galaxies at approximately the same redshift as the Lyman Limit system, whose centers are displaced by 34 and 87 kpc from the line of sight. Damping wings seen in the Lyα absorption of the Lyman Limit system indicate that log N (H I) = 17.98. Singly ionized forms of several elements indicate that there is much additional material containing ionized hydrogen. The ionization fractions of oxygen and nitrogen are strongly coupled to that of H. This property allowed us to use N(O I) to derive [O/H] = −0.20, a finding that is not sensitive to ionization effects. The near solar abundance of oxygen contrasts with a strong deficiency of nitrogen: from the lack of N I features we conclude that [N/O] < −0.67. Evidently, this system has experienced significant enrichment from high mass stars with a low initial metallicity, but without much accompanying secondary N production from intermediate mass stars. |
|
|
|
|