Neutrino-nucleus reaction cross sections for neutrino detection and nucleosynthesis in supernova explosions

Neutrino-nucleus cross sections relevant to detection of supernova and reactor neutrinos as well as synthesis of elements in supernova explosions are evaluated by shell-model calculations with new shell-model Hamiltonians, which can describe spin degree's of freedom in nuclei very well. The new Hamiltonians, SFO for p-shell, GXPF1J for pf-shell and VMU (monopole-based universal interaction), have proper tensor components in common, which lead to proper shell-evolutions. We can now reproduce experimental ν-induced cross sections available, that is, those of ¹²C and ⁵⁶Fe, and evaluate the cross sections with sound reliability in various light and medium heavy nuclei. Updated ν-induced cross sections on ¹²C, ¹³C, ¹⁶O, ⁵⁶Fe, ⁵⁶Ni and ⁴⁰Ar are presented and compared to those previously obtained. The cross sections on ¹²C are applied to study light element synthesis in supernova explosions and neutrino oscillation parameters. Coherent scattering cross sections on ¹²C and ¹³C can be good probes of neutron distributions of the nuclei. ¹³C is an attractive target for the detection of very low energy neutrinos below 10 MeV. Accurate evaluations of ν-induced cross sections are carried out for ¹⁶O and ⁴⁰Ar, which are powerful targets for the detection of supernova neutrinos. Cross sections folded over neutrino spectra with and without the oscillation effects are also compared to each other to see how they are sensitive to the oscillation effects.