Neutrino-induced reactions onFe56andNi56, and production ofMn55in population III stars

Abstract

Neutrino-induced reactions on $^{56}\mathrm{Fe}$ and $^{56}\mathrm{Ni}$ are investigated based on a new shell-model Hamiltonian for $\mathit{pf}$ shell. The calculated charged current reaction cross section on $^{56}\mathrm{Fe}$ induced by decay-at-rest (DAR) neutrinos is shown to be consistent with the observation. The Gamow-Teller strength in $^{56}\mathrm{Ni}$ 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 $^{55}\mathrm{Mn}$ in population III stars are shown to be enhanced for the new Hamiltonian.