Neutrino-nucleus reactions based on new shell model Hamiltonians

A new shell model Hamiltonian for p-shell nuclei which properly takes into account important roles of spin-isospin interactions is used to obtain cross sections of neutrino-C-12 reactions induced by decay-at-rest neutrinos as well as supernova neutrinos. Branching ratios to various decay channels are calculated by the Hauser-Feshbach theory. Neutrino-He-4 reactions are also investigated by using recent shell model Hamiltonians. The reaction cross sections are found to be enhanced for both C-12 and He-4 compared with previous calculations. As an interesting consequence of this, a possible enhancement of the production yields of light elements, Li-7 and B-11, during supernova explosions is pointed out.