Re-examination of the β-decay properties of As isotopes

The beta-decay properties of 67-80As nuclei have been investigated within the framework of the proton-neutron quasi-particle random phase approximation (pn-QRPA) model. The nuclear deformation obtained from the finite range droplet model is used as an input parameter in the pn-QRPA model for the analysis of beta-decay properties including Gamow-Teller strength distributions, log ft, beta-decay half-lives and stellar beta +/- decay rates. The predicted log ft values were fairly consistent with the observed data. The computed beta-decay half-lives matched the measured values by a factor of 10. The stellar rates were compared with the shell model outcomes. At high densities and temperatures, the beta+ and electron capture rates had a finite contribution. However, the beta- and positron capture rates are only significant at high temperatures and low densities. The pn-QRPA rates outperformed the shell model rates by a factor of 22 or more.