Cross sections and fragment distributions from neutrino-induced fission on r-process nuclei

We study neutrino-induced processes that might contribute to the observed patterns in the r-process abundances in low-metallicity, old galactical halo stars. The neutrino-nucleus interaction is calculated within the random phase approximation, while the decay of excited levels in the daughter nucleus is followed via the evaporation-fission code ABLA. We calculate the fission cross sections for selected neutron-rich progenitor nuclei with Z(prog) > 80. More importantly, we calculate the mass and charge distributions of the fission fragments as well as the number of neutrons set free in the neutrino-induced reactions. We particularly study a sample of nuclei with A(prog) > 200 representing r-process progenitors during their decay towards the valley of stability after the r-process freeze-out. (c) 2005 Elsevier B.V. All rights reserved.