The Iron Group Abundance Pattern of the Damped Lyman-Alpha Absorber at [ITAL]z[/ITAL] = 1.3726 toward the QSO 0935+417

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Abstract
We present high-resolution (18 km s-1), high S/N (≈ 50) observations of the Zn II, Cr II, Fe II, Mn II, and Ti II absorption in the damped Lyα system at z = 1.3726 toward the QSO 0935+417. We measure a Zn metallicity ([Zn/H] = -0.70) in this system that is about 3 times greater than those of the lower redshift damped absorbers toward 3C 286 and 0454+039 and comparable to those of the highest metallicity absorbers observed at higher redshifts. The Cr II and Fe II column densities yield gas-phase abundance ratios of [Cr/Zn] = -0.10 and [Fe/Zn] = -0.29 that are much greater than even those of low-density Galactic ISM sightlines and imply that the 0935+417 absorber is essentially a dust-free environment. We also find evidence of a Mn underabundance and a Ti overabundance that is consistent with the nucleosynthetic signature of a gas cloud with a base metallicity similar to that of metal-poor Galactic stars. In summary, the iron group abundance pattern of the z = 1.3726 absorber toward 0935+417 is what one might expect from a dust-free, metal-poor galaxy evolving on a metallicity track similar to that of the Milky Way.