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arXiv · 0710.0251

nu-Process Nucleosynthesis in Population III Core-Collapse Supernovae

Takashi Yoshida·Hideyuki Umeda·Ken'ichi Nomoto
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Abstract

We investigate the effects of neutrino-nucleus interactions (the nu-process) on the production of iron-peak elements in Population III core-collapse supernovae. The nu-process and the following proton and neutron capture reactions produce odd-Z iron-peak elements in complete and incomplete Si burning region. This reaction sequence enhances the abundances of Sc, Mn, and Co in the supernova ejecta. The supernova explosion models of 15 M_sol and 25 M_sol stars with the nu-process well reproduce the averaged Mn/Fe ratio observed in extremely metal-poor halo stars. In order to reproduce the observed Mn/Fe ratio, the total neutrino energy in the supernovae should be 3 - 9 x 10^{53} ergs. Stronger neutrino irradiation and other production sites are necessary to reproduce the observed Sc/Fe and Co/Fe ratios, although these ratios increase by the nu-process.

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Takashi Yoshida, Hideyuki Umeda, Ken'ichi Nomoto. 2007-10-01. nu-Process Nucleosynthesis in Population III Core-Collapse Supernovae. https://doi.org/10.1086/523833

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