Weak interaction rates for Kr and Sr waiting-point nuclei under rp-process conditions

TL;DR

This paper investigates weak interaction rates in neutron-deficient Kr and Sr isotopes under rp-process conditions, emphasizing the importance of continuum electron capture and using a microscopic model aligned with recent measurements.

Contribution

It provides new calculations of weak rates using a deformed QRPA model that matches recent experimental Gamow-Teller data, highlighting the role of continuum electron capture.

Findings

Continuum electron capture significantly affects weak rates at rp-process conditions.

The microscopic model accurately reproduces half-lives and Gamow-Teller distributions.

Weak rates vary notably with density and temperature.

Abstract

Weak interaction rates are studied in neutron deficient Kr and Sr waiting-point isotopes in ranges of densities and temperatures relevant for the rp-process. The nuclear structure is described within a microscopic model (deformed QRPA) that reproduces not only the half-lives but also the Gamow-Teller strength distributions recently measured. The various sensitivities of the decay rates to both density and temperature are discussed. Continuum electron capture is shown to contribute significantly to the weak rates at rp-process conditions.