Nucleosynthesis of Light Elements and Heavy r-Process Elements through the ν-Process in Supernova Explosions

We study the nucleosynthesis of the light elements Li and B and the rprocess elements in Type II supernovae from the point of view of supernova neutrinos and Galactic chemical evolution. We investigate the influence of the luminosity and average energy (temperature) of supernova neutrinos on these two nucleosynthesis processes. Common models of the neutrino luminosity, which is parameterized by the total energy Eν and decay time τν and neutrino temperature are adopted to understand both processes. We adopt the model of the supernova explosion of a 16.2 M⊙ star, which corresponds to SN 1987A, and calculate the nucleosynthesis of the light elements by postprocessing. We find that the ejected masses of Li and B are roughly proportional to the total neutrino energy and are weakly dependent on the decay time of the neutrino luminosity. As for the r-process nucleosynthesis, we adopt the same models of the neutrino luminosity in the neutrino-driven wind models of a 1.4 M⊙ neutron star. We find that the r-process nucleosynthesis is affected through the peak neutrino luminosity, which depends on Eν/τν . The observed r-process abundance pattern is better reproduced at a low peak neutrino luminosity. We also discuss the unresolved Current address: National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan; [email protected] Current address: Center for Nuclear Study, Graduate School of Science, University of Tokyo, Hirosawa, Wako, Saitama 351-0198, Japan