Stellar electron-capture rates calculated with the finite-temperature relativistic random-phase approximation

Abstract

We introduce a self-consistent microscopic theoretical framework for modeling the process of electron capture on nuclei in stellar environment, based on relativistic energy density functionals. The finite-temperature relativistic mean-field model is used to calculate the single-nucleon basis and the occupation factors in a target nucleus, and ${J}^{\ensuremath{\pi}}={0}^{\ifmmode\pm\else\textpm\fi{}}$, ${1}^{\ifmmode\pm\else\textpm\fi{}}$, and ${2}^{\ifmmode\pm\else\textpm\fi{}}$ charge-exchange transitions are described by the self-consistent finite-temperature relativistic random-phase approximation. Cross sections and rates are calculated for electron capture on $^{54,56}\mathrm{Fe}$ and $^{76,78}\mathrm{Ge}$ in stellar environment, and results compared with predictions of similar and complementary model calculations.