ABUNDANCE PATTERNS OF HEAVY-ELEMENTS IN DAMPED LY-ALPHA GALAXIES

We present a quantitative analysis of the abundances of heavy elements in damped Ly alpha galaxies in the sample of Lu et al. In particular, we compare the observed gas-phase abundances with those expected when the intrinsic (i.e., nucleosynthetic) pattern is the same as that in either the Sun or in Galactic halo stars and when the depletion patter n is the same as that in the warm Galactic interstellar medium, but wi th various values of the dust-to-metals ratio. We find that the observ ations are equally consistent with the solar and halo-star intrinsic p atterns and that they favor some depletion, the typical dust-to-metals ratio being 40%-90% of that in the Milky Way today. However, neither intrinsic pattern matches the observations perfectly. For the solar pa ttern, the discrepancy is mainly with [Mn/Fe], while for the halo-star pattern, the discrepancy is with [Zn/Fe], [Ni/Fe], and possibly [Al/F e]. Our analysis does not support the claim by Lu et al, that the damp ed Ly alpha galaxies have halo-star abundance patterns and no dust dep letion.