论文部分内容阅读
~(134)Ce原子核现有的实验数据显示B_(4/2)=B(E2;4_1~+→2_1~+)/B(E2;2_1~+→0_1~+)的值小于1,超出了目前集体模型所预言的范围。如果这种反常的B_(4/2)值是正确的,那么将会成为挑战传统模型的一个重大的核结构问题。本工作首先通过多普勒反冲距离法测量了~(134)Ce激发态的寿命,然后根据测出的寿命来检验这种反常的正确性。~(134)Ce的激发态通过重离子融合蒸发反应~(122)Sn(~(16)O,4n)~(134)Ce布居。~(16)O束流由中国原子能科学研究院的HI-13串列加速器提供,能量为
The existing experimental data of ~ (134) Ce nucleus show that the value of B 4/2 = B (E2; 4_1 ~ + → 2_1 ~ +) / B (E2; 2_1 ~ + → 0_1 ~ +) is less than 1, The range predicted by the current collective model. If this unusual value of B_ (4/2) is correct, it will be a major nuclear structural problem that challenges the traditional model. In this work, we first measured the lifetime of ~ (134) Ce excited states by the Doppler recoil distance method, and then tested the anomaly according to the measured lifetime. The excited states of ~ (134) Ce reside in the (122) Sn (~ (16) O, 4n) ~ (134) Ce by heavy ion fusion evaporation. The ~ (16) O beam is provided by the HI-13 tandem accelerator of China Institute of Atomic Energy, and its energy is