Systematic study of two-proton radioactivity with a screened electrostatic barrier

Abstract

In this study, a phenomenological model is proposed based on Wentzel-Kramers-Brillouin (WKB) theory and applied to investigate the two-proton ($2p$) radioactive half-lives of nuclei near or beyond the proton drip line. The total diproton-daughter nucleus interaction potential is composed of the Hulthen-type electrostatic term and the centrifugal term. The calculated $2p$ radioactive half-lives can accurately reproduce the existing 10 experimental datasets of five true $2p$ radioactive nuclei with $\sigma$ = 0.736. In addition, we extend this model to predict the half-lives of possible $2p$ radioactive nuclei whose $2p$ radioactivity is energetically allowed or observed but not yet quantified in NUBASE2016. The predicted results are in agreement with those obtained using the Gamow-like model, generalized liquid drop model, Sreeja formula, and Liu formula.