Roles of one-step process on neutrino scattering off 12C

Neutrino (ν) (antineutrino (ν¯)) scattering off 12C in the energy range from a few to tens of MeV is one of key reactions for the ν-process in the nucleosynthesis of light nuclei, which usually assumes two-step process. Target nucleus is excited through various transitions by incident ν(ν¯), and subsequently decay into other nuclei with emitting particles. However, one-step process is also feasible, in which incident ν(ν¯) strips directly one nucleon from target nucleus. Consequently, the one-step process may affect abundances of 11C and 11B in addition to the two-step process. We investigate the one-step process in the ν(ν¯) quasi-elastic scattering off 12C with inclusion of the final state interaction between outgoing nucleon and residual nucleus, and evaluate effects of the one-step process in the relevant cross sections. The one-step process turned out to be comparable to the two-step process and the amount could be sensitive on the FSI.