Nuclear electron capture rate in stellar interiors and the case of 7Be

TL;DR

This paper calculates nuclear electron capture rates in stellar interiors using a modified screening potential and non-Gaussian electron momentum distribution, finding a 7-10% increase over standard models for 7Be in the solar core.

Contribution

It introduces a non-Gaussian q-distribution approach to electron capture rate calculations in stellar plasmas, extending beyond traditional Debye-Huckel models.

Findings

Increase of 7-10% in 7Be electron capture rate in solar core.

Reduction of 8B solar neutrino flux by the same percentage.

Standard 7Be flux remains unaffected.

Abstract

Nuclear electron capture rate from continuum in an astrophysical plasma environment (like solar core) is calculated using a modified Debye-Huckel screening potential and the related non-Gaussian q-distribution of electron momenta. For q=1 the well-known Debye-Huckel results are recovered. The value of q can be derived from the fluctuation of number of particles and temperature inside the Debye sphere. For 7Be continuum electron capture in solar core, we find an increase of 7 -- 10 percent over the rate calculated with standard Debye-Huckel potential. The consequence of this results is a reduction of the same percentage of the SSM 8B solar neutrino flux, leaving unchanged the SSM 7Be flux.