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arXiv · 0708.1748

r-Process Nucleosynthesis in Shocked Surface Layers of O-Ne-Mg Cores

H. Ning·Y. -Z. Qian·B. S. Meyer
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Abstract

We demonstrate that rapid expansion of the shocked surface layers of an O-Ne-Mg core following its collapse can result in r-process nucleosynthesis. As the supernova shock accelerates through these layers, it makes them expand so rapidly that free nucleons remain in disequilibrium with alpha-particles throughout most of the expansion. This allows heavy r-process isotopes including the actinides to form in spite of the very low initial neutron excess of the matter. We estimate that yields of heavy r-process nuclei from this site may be sufficient to explain the Galactic inventory of these isotopes.

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H. Ning, Y. -Z. Qian, B. S. Meyer. 2007-08-13. r-Process Nucleosynthesis in Shocked Surface Layers of O-Ne-Mg Cores. https://doi.org/10.1086/522372

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