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

TL;DR

This paper develops a self-consistent microscopic model using relativistic energy density functionals to accurately calculate electron-capture rates on nuclei in stellar environments, improving understanding of stellar evolution.

Contribution

It introduces a novel finite-temperature relativistic RPA framework combined with energy density functionals for modeling stellar electron capture processes.

Findings

Calculated electron-capture rates for Fe and Ge isotopes in stellar conditions.

Results show good agreement with existing models and improve accuracy.

Provides a comprehensive method for nuclear transition calculations at finite temperature.

Abstract

We introduce a self-consistent microscopic theoretical framework for modelling 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 $J^{\pi} = 0^{\pm}$, $1^{\pm}$, $2^{\pm}$ 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 54,56Fe and 76,78Ge in stellar environment, and results compared with predictions of similar and complementary model calculations.