Neutrino-induced reactions on Fe-56 and Ni-56, and production of Mn-55 in population III stars

Neutrino-induced reactions on Fe-56 and Ni-56 are investigated based on a new shell-model Hamiltonian for pf shell. The calculated charged current reaction cross section on Fe-56 induced by decay-at-rest (DAR) neutrinos is shown to be consistent with the observation. The Gamow-Teller strength in Ni-56 is found to be more spread compared to previous calculations and result in a considerably large branching ratio for the proton knock-out channel. As a consequence of this, the production yields of heavy elements such as Mn-55 in population III stars are shown to be enhanced for the new Hamiltonian.

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