Calculation of double-β decay half-lives using an improved Primakoff-Rosen formula  

作　　者：Qi-Jun Zhi Xiao-Ping Zhang Ji-Lin You Qiang Zheng Zhong-Zhou Ren 支启军;张小平;游击林;郑强;任中洲(School of Physics and Electronic Sciences,Guizhou Normal University,Guiyang 550001,China;Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing,Guizhou Normal University,Guiyang,China;State Key Laboratory of Lunar and Planetary Sciences,Macao University of Science and Technology,Macao 999078,China;School of Science,Tianjin University of Technology,Tianjin 300384,China;School of Physics Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]School of Physics and Electronic Sciences,Guizhou Normal University,Guiyang 550001,China [2]Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing,Guizhou Normal University,Guiyang,China [3]State Key Laboratory of Lunar and Planetary Sciences,Macao University of Science and Technology,Macao 999078,China [4]School of Science,Tianjin University of Technology,Tianjin 300384,China [5]School of Physics Science and Engineering,Tongji University,Shanghai 200092,China

出　　处：《Chinese Physics C》2021年第8期83-89,共7页中国物理C（英文版）

基　　金：Supported by the National Natural Science Foundation of China(U1731238,11761161001,11105079,11535004,11375086,11975167,12035011);the Science and Technology Development Fund(FDCT)of Macao(020/2014/A1,008/2017/AFJ,0042/2018/A2);the Science and Technology Foundation of Guizhou Province((2016)4008,(2017)5726-37);the foundation of Guizhou Provincial education Department(KY(2020)003)。

摘　　要：A systematic analysis on experimental data of the half-lives of nuclear double-β decays with two neutrinos(2vββ)is performed based on the analytical formula proposed by Primakoff and Rosen.We improve the formula by considering the shell effects and refining the energy dependence of the phase-space factor.This improved formula can closely describe all available experimental half-lives of 2vβ^(-)β^(-)decays,both for ground-state transitions and transitions from ground states of parent nuclei to the first 0+excited states of daughter nuclei.The calculated half-lives agree with the experimental data of ground-state transitions of all known eleven nuclei with an aver-age factor of 2.3.Further predictions are provided for 2vββ-decay candidates with decay energies above 0.5 MeV.We compare different theoretical predictions and emphasize the importance of experimental measurements on the half-lives of double-β transitions between the ground state of 48Ca,76 Ge,and 136Xe and the first 0+excited states of their corresponding daughter nuclei,which will be very useful for understanding the underlying mechanisms of double-β decays and for further studying the shell effects on nuclear transition matrix elements.

关 键 词：double-βdecay half-lives Primakoff-Rosen formula phase-space factor 

分 类 号：O571.322[理学—粒子物理与原子核物理]