Neutrino-nucleus interaction and supernova r-process nucleosynthesis

We discuss various neutrino-nucleus interactions in connection with the supernova r-process nucleosynthesis, which possibly occurs in the neutrino-driven wind of a young neutron star. These interactions include v_e and v̄_e absorptions on free nucleons, v_e captures on neutron-rich nuclei, and neutral-current v_μ(τ) and v̄_μ(τ) interactions with α-particles and neutron-rich nuclei. We describe how these interactions can affect the r-process nucleosynthesis and discuss the implications of their effects for the physical conditions leading to a successful supernova r-process. We conclude that a low electron fraction and/or a short dynamic time scale may be required to give the sufficient neutron-to-seed ratio for an r-process in the neutrino-driven wind. In the case of a short dynamic time scale, the wind has to be contained during the r-process. Possible mechanisms which can give a low electron fraction or contain the wind are discussed.