On the role of pairing correlations in calculation of β-decay half-lives within QRPA formalism

Abstract

In this paper we show that the proton-neutron residual interaction can play an important role in the reliability of calculated β-decay half-lives. It may also improve the prediction power of the quasiparticle random phase approximation (QRPA) model. We further demonstrate that a reasonable choice of the particle-particle (attractive) and particle-hole force (repulsive) parameters can result in calculated half-lives in very good comparison with the measured ones. Pairing gaps have affect on calculated half-lives which we explore in this paper. We present our half-lives calculation using the proton-neutron QRPA (pn-QRPA) model possessing a multi-shell single-particle deformed space including a schematic interaction for some medium mass neutron-deficient nuclei undergoing β+/EC decay. Our study shows a better agreement with the available experimental data as compared to former calculations.