Metal-rich damped Ly{alpha} systems at z~2

The metal-rich sample of DLAs at z_abs~2 probes metallicities as high as the Galactic disc and the most metal-rich dwarf spheroidals (dSphs), permitting an analysis of many elements typically observed in DLAs (Fe, Zn, Cr, Mn, Si, and S) in comparison to stellar abundances observed in the Galaxy and its satellites (in particular dSphs).

Our main conclusions are: (1) non-solar [Zn/Fe] abundances in metal-poor Galactic stars and in dSphs over the full metallicity range probed by DLAs, suggest that Zn is not a simple proxy for Fe in DLAs and therefore not a suitable indicator of dust depletion. After correcting for dust depletion, the majority of DLAs have subsolar [Zn/Fe] similar to dSphs; (2) at [Fe/H]~-0.5, a constant [Mn/Fe]~-0.5 and near-solar [{alpha}/Fe] (requiring an assumption about dust depletion) are in better agreement with dwarf galaxies than Galactic disc stars; (3) [{alpha}/Zn] is usually solar or subsolar in DLAs.