标题： 136Xe的两中微子双β衰变的核矩阵元 显示英文标题

标题： Nuclear matrix element for two neutrino double beta decay from 136Xe

摘要： 核素136Xe的两中微子双β衰变（DBD）的核矩阵元由FSQP（费米面准粒子模型）进行了评估，其中使用了通过电荷交换反应测得的实验GT强度以及通过β衰变率测得的GT强度。 两中微子DBD矩阵元由中间核中低能（费米面）准粒子态的单β矩阵元的乘积之和给出。 136Xe是一个半魔数核，具有闭合的中子壳层，因此β+跃迁几乎被抑制。 因此，两中微子DBD被大大抑制。 评估得到的两中微子DBD矩阵元与观测值一致。 显示英文摘要

摘要： The nuclear matrix element for the two neutrino double beta decay (DBD) of 136Xe was evaluated by FSQP (Fermi Surface Quasi Particle model), where experimental GT strengths measured by the charge exchange reaction and those by the beta decay rates were used. The 2 neutrino DBD matrix element is given by the sum of products of the single beta matrix elements via low-lying (Fermi Surface) quasi-particle states in the intermediate nucleus. 136Xe is the semi-magic nucleus with the closed neutron-shell, and the beta + transitions are almost blocked. Thus the 2 neutrino DBD is much suppressed. The evaluated 2 neutrino DBD matrix element is consistent with the observed value.