论文标题
短寿命$^{68} $ ni的电荷半径与偶极性极化相关
Charge radius of the short-lived $^{68}$Ni and correlation with the dipole polarizability
论文作者
论文摘要
我们介绍了\ mbox {$ n = 40 $}子壳闭合并提取其核电半径的第一个激光光谱测量$^{68} $ ni。由于这是唯一测量偶极极化性$α_ {\ rm d} $的短寿命同位素，因此这些可观察物的组合为核结构理论提供了基准。我们将它们与基于不同手性的两核和三核子相互作用的新型耦合群集计算进行了比较，该相互作用观察到电荷半径和偶极极化性之间的强相关性，类似于稳定的核$^{48} $ CA。耦合群集理论中的三粒子 - 三孔相关性基本上改善了实验数据的描述，这允许限制$^{68} $ ni的中子半径和中子皮肤。
We present the first laser spectroscopic measurement of the neutron-rich nucleus $^{68}$Ni at the \mbox{$N=40$} subshell closure and extract its nuclear charge radius. Since this is the only short-lived isotope for which the dipole polarizability $α_{\rm D}$ has been measured, the combination of these observables provides a benchmark for nuclear structure theory. We compare them to novel coupled-cluster calculations based on different chiral two- and three-nucleon interactions, for which a strong correlation between the charge radius and dipole polarizability is observed, similar to the stable nucleus $^{48}$Ca. Three-particle--three-hole correlations in coupled-cluster theory substantially improve the description of the experimental data, which allows to constrain the neutron radius and neutron skin of $^{68}$Ni.
