Experimental study of the lifetime and phase transition in neutron-rich Zr 98 , 100 , 102
Experimental study of the lifetime and phase transition in neutron-rich Zr 98 , 100 , 102
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富中子Zr 98 , 100 , 102 寿命和相变的实验研究
DOI：
10.1103/physrevc.96.054323
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发表时间：
2017
影响因子：
3.1
通讯作者：
Ansari S
中科院分区：
文献类型：
--
作者：
Ansari S
在A约为100的丰中子核中观察到了快速的形状变化。特别地，在N = 60时，Zr和Sr同位素链中观察到基态形变的突然发生：核中的低位态近似为球形，而具有转动特征的低位态近似为球形。短至几皮秒的核寿命可以用（Ce）闪烁器使用快速计时技术测量，这是系统研究该地区形状演变的关键因素。利用位于劳厄-朗之万研究所PF 1B冷中子束线上的EXILL-FATIMA装置，利用中子诱发裂变研究了和区裂变碎片激发态寿命。特别地，我们应用广义质心差分方法推导了核（N= 58）、、和（）的低激发态寿命。结果进行了讨论的背景下，通过比较实验的过渡强度与理论计算，使用相互作用玻色子模型和蒙特卡罗壳模型中的Zr链中的假定相变。
Rapid shape changes are observed for neutron-rich nuclei withAaround 100. In particular, a sudden onset of ground-state deformation is observed in the Zr and Sr isotopic chains atN= 60: Low-lying states innuclei are nearly spherical, while those withhave a rotational character. Nuclear lifetimes as short as a few picoseconds can be measured using fast-timing techniques with(Ce) scintillators, yielding a key ingredient in the systematic study of the shape evolution in this region. We used neutron-induced fission ofandto study lifetimes of excited states in fission fragments in theregion with the EXILL-FATIMA array located at the PF1B cold neutron beam line at the Institut Laue-Langevin. In particular, we applied the generalized centroid difference method to deduce lifetimes of low-lying states for the nuclei(N= 58),, and(). The results are discussed in the context of the presumed phase transition in the Zr chain by comparing the experimental transition strengths with the theoretical calculations using the interacting boson model and the Monte Carlo shell model.