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arXiv · 1101.1227

Chemical Enrichment in the Carbon-enhanced Damped Lyman $α$ System

Chiaki Kobayashi·Nozomu Tominaga·Ken'ich Nomoto
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Abstract

We show that the recently observed elemental abundance pattern of the carbon-rich metal-poor Damped Lyman $α$ (DLA) system is in excellent agreement with the nucleosynthesis yields of faint core-collapse supernovae of primordial stars. The observed abundance pattern is not consistent with the nucleosynthesis yields of pair-instability supernovae. The DLA abundance pattern is very similar to that of carbon-rich extremely metal-poor (EMP) stars, and the contributions from low-mass stars and/or binary effects should be very small in DLAs. This suggests that chemical enrichment by the first stars in the first galaxies is driven by core-collapse supernovae from $\sim 20-50 M_\odot$ stars, and also supports the supernova scenario as the enrichment source of EMP stars in the Milky Way Galaxy.

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Chiaki Kobayashi, Nozomu Tominaga, Ken'ich Nomoto. 2011-02-11. Chemical Enrichment in the Carbon-enhanced Damped Lyman $α$ System. https://doi.org/10.1088/2041-8205%2F730%2F2%2Fl14

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