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The r-process in supernova explosions from the collapse of O-Ne-Mg cores

S. Wanajo·M. Tamamura·N. Itoh·K. Nomoto·Y. Ishimaru·T. C. Beers·S. Nozawa
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Abstract

We examine r-process nucleosynthesis in a "prompt supernova explosion" from an 8-10 Msun progenitor star, as an alternative scenario to the "neutrino wind" mechanism. In the present model, the progenitor star has formed an oxygen-neon-magnesium core at its center. The core-collapse simulations are performed with a one-dimension, Newtonian hydrodynamic code. We obtain a very weak prompt explosion, in which no r-processing occurs. We further simulate energetic prompt explosions by enhancement of the shock-heating energy, in order to investigate conditions necessary for the production of r-process nuclei in such events. The highly neutronized ejecta (Ye = 0.14-0.20) leads to robust production of r-process nuclei; their relative abundances are in excellent agreement with the solar r-process pattern. Our results suggest that prompt explosions of 8-10 Msun stars with oxygen-neon-magnesium cores can be a promising site of r-process nuclei.

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S. Wanajo, M. Tamamura, N. Itoh, K. Nomoto, Y. Ishimaru, T. C. Beers, S. Nozawa. 2003-05-02. The r-process in supernova explosions from the collapse of O-Ne-Mg cores. https://doi.org/10.1086/376617

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