Research on two-proton radioactivity in density-dependent cluster model

The density-dependent cluster model(DDCM) provides a unified framework to study α decay,heavy-cluster radioactivity,and proton emission.Two-proton(2p) radioactivity is a rare decay mode of exotic nuclei near or beyond the drip-line.It is of great interest to explore the applicability of DDCM to this exotic decay mode.In this work,DDCM has been extended to study 2p radioactivity.The 2p-radioactivity half-lives are calculated for several known 2p-emitters,including19Mg,45Fe,48Ni,54Zn,and67Kr.The theoretical results are in good agreement with the experimental data,with the standard deviations comparable to or smaller than those given by some other theoretical models and empirical formulas.We also predict the half-lives of a number of possible 2p-emitters with S2p<0 and Sp> 0 using the new data from AME2020 and NUBASE2020.These predictions serve as useful references for future experimental and theoretical investigations on 2p radioactivity.