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
• 来源期刊: 中国物理C（英文版）
• 年，卷（期）: 2021,（8）
• 所属期刊栏目: NUCLEAR PHYSICS
• 页码范围: 83-89
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-1137/ac0097

摘要

A systematic analysis on experimental data of the half-lives of nuclear double-β decays with two neutri-nos(2vββ)is performed based on the analytical formula proposed by Primakoff and Rosen.We improve the for-mula 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 trans-itions and transitions from ground states of parent nuclei to the first 0+excited states of daughter nuclei.The calcu-lated 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 48 Ca,76 Ge,and 136 Xe 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.