2006/06/22 by Jason X. Prochaska, J. X. Prochaska, John M. O’Meara +6 · 65 citations
Chemistry · Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Chemistry #Galaxies: Formation, Evolution, Phenomena #Galaxy #Geometry #Intergalactic medium #Line (geometry) #Lyman limit #Metal #Metallicity #Photoionization #Physics #Quantum mechanics #Quasar #Redshift #Sky #Spectral line #Stellar, planetary, and galactic studies #Universe #astro-ph
paper · pdf · doi:10.1086/507867
published in The Astrophysical Journal 648(2), L97-L100 (IOP Publishing) · 6 pages, 2 figures. Submitted to ApJL; Revised June 22, 2006
arxiv created 2006/06/22 · openalex publication_date 2006/08/28 · arxiv updated 2011/02/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present abundance measurements for two super-Lyman limit systems (SLLSs; quasar absorption-line systems with 10 19 cm -2 < N < 10 20.3 cm -2 ) selected from a set of metal-strong absorbers in the SDSS quasar database. After applying estimate corrections for photoionization effects, we derive gas-phase metallicities of [M/H] = +0.7 ± 0.2 dex for the SLLS at z = 1.7749 toward SDSS 0927+5621 and [M/H] = +0.05 ± 0.1 dex for the SLLS at z = 1.7678 toward SDSS 0953+5230. The former exhibits one of the highest gas metallicities of any astrophysical environment, and its total metal surface density exceeds that of nearly every known damped Lyα system. The properties of these absorbers—high metallicity and large velocity width (Δ v > 300 km s -1 )—resemble those of gas observed in absorption in the spectra of bright, star-forming galaxies at high redshift. We discuss the metal mass density of the SLLSs based on these observations and our SLLS survey, and we argue that a conservative estimate to the total metal budget at z = 2 is greater than 15% of the total, suggesting that metal-rich LLSs may represent the dominant metal reservoir in the young universe.