Weak interaction rates of neutron-rich nuclei and the<b><i>r</i></b>-process nucleosynthesis

Abstract

Weak interaction rates for very short-lived neutron-rich nuclides involved in the r process are mostly beyond the experimental reach at the present time. Accurate theoretical predictions demand a coherent extrapolation of different nuclear properties away from the experimentally known regions. The \ensuremath{\beta}-decay and neutrino-capture rates are estimated within the extended Thomas-Fermi plus Strutinsky integral method and the continuum quasiparticle random phase approximation. This approximation on the self-consistent calculation of the ground-state and \ensuremath{\beta}-decay properties is described. The large-scale calculations of the \ensuremath{\beta}-strength function for stable and short-lived nuclei are performed to estimate, simultaneously, the \ensuremath{\beta}-decay and electron neutrino capture rates for nuclides of relevance to the r-process nucleosynthesis. A comparison of the results with existing experimental data, global calculations, and self-consistent microscopic predictions is presented.