Chinese Physics C ( IF 3.6 ) Pub Date : 2021-07-26 , DOI: 10.1088/1674-1137/ac0097 Qi-Jun Zhi 1, 2 , Xiao-Ping Zhang 3 , Ji-Lin You 3 , Qiang Zheng 4 , Zhong-Zhou Ren 5
A systematic analysis on experimental data of the half-lives of nuclear double- decays with two neutrinos ( ) 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 decays, both for ground-state transitions and transitions from ground states of parent nuclei to the first 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 average factor of 2.3. Further predictions are provided for -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- transitions between the ground state of Ca, Ge, and Xe and the first excited states of their corresponding daughter nuclei, which will be very useful for understanding the underlying mechanisms of double- decays and for further studying the shell effects on nuclear transition matrix elements.
中文翻译:
使用改进的 Primakoff-Rosen 公式计算双 β 衰变半衰期 国家自然科学基金项目 (U1731238, 11761161001, 11105079, 11535004, 11375086, 119751030, 1197521030, 119751030, 1CT 科技发展基金)澳门(020/2014/A1、008/2017/AFJ、0042/2018/A2)、贵州省科技基金((2016)4008、(2017)5726-37)、贵州省教育基金部门 (KY(2020)003)
基于Primakoff和Rosen提出的解析公式,对两个中微子( )的核双衰变半衰期的实验数据进行了系统分析。我们通过考虑壳效应和细化相空间因子的能量依赖性来改进公式。这个改进的公式可以精确地描述所有可用的衰变实验半衰期,包括基态跃迁和从母核基态到子核第一激发态的跃迁。计算的半衰期与所有已知 11 个原子核的基态跃迁的实验数据一致,平均因子为 2.3。提供了进一步的预测-衰变能量高于 0.5 MeV 的衰变候选者。我们比较了不同的理论预测,并强调了对Ca、Ge 和Xe基态与其相应子核的第一激发态之间双跃迁半衰期的实验测量的重要性,这对于理解非常有用双衰变的潜在机制和进一步研究核跃迁矩阵元素的壳效应。