Neutrino-induced Reactions on $^{16}$O: Supernova Neutrino Detection and Nucleosynthesis of Light Elements*

  Neutrino-induced reactions on $^{16}$O are investigated by shell-model calculations with new shell-model Hamiltonians, which can describe well the structure of $p$-shell and $p$-$sd$ shell nuclei.  Spin-dipole strength distributions in $^{16}$O are studied with the new Hamiltonians. Muon-capture rates on $^{16}$O are evaluated to discuss the quenching of the axial-vector coupling in nuclear medium.

   Charged-current and neutral-current reaction cross sections are obtained in various particle and $\gamma$ emission channels as well as the total ones at neutrino energies up to $E_{\nu$ = 100 MeV. Partial cross sections for single- and multi-particle emission channels are evaluated by using the branching ratios obtained by the Hauser-Feshbach model. Event spectra of the charged-current reactions as function of recoil energy of electron/positron are discussed for future supernova (SN) neutrino detection at the Super-Kamiokande.

   Effects of multi-particle emission channels on nucleosynthesis in core-collapse SN explosions are investigated. Inclusion of $\alpha$p emission channels is found to lead to an enhancement of the production yields of $^{11}$B and $^{11}$C.