论文标题
富含中子的SR同位素接近n = 60形状过渡的单粒子结构
Single-particle structure in neutron-rich Sr isotopes approaching the N = 60 shape transition
论文作者
论文摘要
背景：中子数n = 60周围的富含中子的核显示了从球形基础状态到98SR和较重核的巨大变形的巨大形状过渡。目的：本研究的目的是研究接近形状过渡区域的单粒子结构。方法：通过使用5.5 AMEV的梁能量（94,95,96SR，T）的D（94,95,96SR，T）一单中性剥离反应研究了中子富含93,94,95SR的水平结构。通过使用老虎和沙克阵列分别检测到从激发态发出的γ射线和后退电荷颗粒。通过对激发能的门控鉴定状态，并在可能的话上识别一致的γ辐射。结果：将射虫核中填充状态的反应的Triton角分布进行了93,94,95SR的比较，与畸变的波出生近似计算进行了比较，以分配和修改旋转和平均量子数量以及提取光谱因子。将结果与壳模型计算和反向（D，P）反应进行比较，并获得了良好的一致性。结论：D（94SR，T）93SR和D（95SR，T）94SR反应的结果与壳模型计算非常吻合。对94SR中0+状态的两级混合分析表明，两种形状的强烈混合。对于D（96SR，T）95SR反应，与壳模型的一致性不太好。 96SR的基态的构型已经比预测的要复杂，因此在n = 60之前已经可以观察到形状跃迁的指示。
Background: Neutron-rich nuclei around neutron number N = 60 show a dramatic shape transition from spherical ground states to prolate deformation in 98Sr and heavier nuclei. Purpose: The purpose of this study is to investigate the single-particle structure approaching the shape transitional region. Method: The level structures of neutron-rich 93,94,95Sr were studied via the d(94,95,96Sr,t) one-neutron stripping reactions at TRIUMF using a beam energy of 5.5 AMeV. γ-rays emitted from excited states and recoiling charged particles were detected by using the TIGRESS and SHARC arrays, respectively. States were identified by gating on the excitation energy and, if possible, the coincident γ radiation. Results: Triton angular distributions for the reactions populating states in ejectile nuclei 93,94,95Sr were compared with distorted wave Born approximation calculations to assign and revise spin and parity quantum numbers and extract spectroscopic factors. The results were compared with shell model calculations and the reverse (d,p) reactions and good agreement was obtained. Conclusions: The results for the d(94Sr,t)93Sr and d(95Sr,t)94Sr reactions are in good agreement with shell model calculations. A two level mixing analysis for the 0+ states in 94Sr suggest strong mixing of two shapes. For the d(96Sr,t)95Sr reaction the agreement with the shell model is less good. The configuration of the ground state of 96Sr is already more complex than predicted, and therefore indications for the shape transition can already be observed before N = 60.
