Publications Repository - Helmholtz-Zentrum Dresden-Rossendorf

We have carried out, for the first time, photodisintegration cross-section measurements on 86Kr using monoenergetic photon beams ranging from the neutron separation energy, Sn = 9.86 MeV, to 13 MeV. We combine our experimental 86Kr(,n)85Kr cross section with results from our recent 86Kr(gamma,gamma) measurement below the neutron separation energy to obtain the complete nuclear dipole response of 86Kr. The new experimental information is used to predict the neutron capture cross section of 85Kr, an important branching point nucleus on the abundance flow path during s-process nucleosynthesis. Our new and more precise 85Kr(n,)86Kr cross section allow us to consider models of asymptotic giant branch (AGB) stars. We find that models of mass smaller than the sun mass, where the 13 C neutron source burns convectively rather than radiatively, represent a possible solution for explaining the highest 86Kr/82Kr ratios observed in meteoritic stardust SiC grains.