资历部分守恒与核同质异能

g_{9/2} shell中的资历守恒和资历违反

Seniority conservation and seniority violation in the g_{9/2} shell

相同粒子的g_{9/2}壳层是第一个可以具有资历混合效应的壳层。我们考虑三种相互作用：一种是保留资历的δ相互作用，一种是不保留资历的四极-四极（QQ）相互作用，第三种是由取自实验（98 Cd）的两体矩阵元素组成的相互作用，它也会导致一些资历混合。我们处理的质子空穴相对于Z=50，N=50的核心。一个令人惊讶的结果是，对于一个总角动量I=4的四粒子系统，有一个状态的资历v=4，它是任何两体相互作用的本征态-资历守恒与否。另外两个态是v=2和v=4的混合态。对于I=6也是如此。另一个有趣的点是，分裂E（I_{max}）-E（I_{min}）对于具有资历守恒相互作用的三个和五个粒子是相同的（一个众所周知的结果），但是对于QQ相互作用是相等和相反的。我们还拟合了δ和QQ相互作用的组合的光谱。Z=40，N=40的核心加上g_{9/2}中子（Zr同位素）也被考虑，尽管认识到核心是变形的。

Rowe-Rosensteel命题的另一种证明和资历守恒

Alternate proof of the Rowe-Rosensteel proposition and seniority conservation

对于在一个单$j$壳层中有三个全同核子的系统，其态可以写成核子对与奇核子的角动量耦合。这些非正交态之间的重叠形成了一个矩阵，该矩阵与Rowe和Rosensteel [Phys. Rev. Lett. { \bf 87}，172501（2001）]。他们所陈述的命题与矩阵的特征值问题和相关子空间的维数有关。在这项工作中，命题将证明从对称性的$6j$符号。从矩阵中可以导出态的维数、本征能和资历守恒条件的代数表达式。

$j=9/2$壳中高阶数部分守恒的解析证明

Analytic proof of partial conservation of seniority in $j=9/2$ shells

最近在一个数值应用中发现了$j=9/2$壳的量子数的部分守恒性。在本文中，作为Zamick和P. Van Isacker [Phys. Rev. C 78（2008）044327]工作的扩展，导出了这个问题的完整解析证明。我们利用分数双亲的单粒子系数和二粒子系数分析了非对角矩阵元素的性质。它被发现，所有的非对角（和相关的对角）矩阵元素可以用简单的方式重新表示，并与某些单粒子cfp的成比例。这种部分动力学对称性的显著发生是$j=9/2$壳层的特殊性质的结果，其中所有$v=3$和5个状态都是唯一定义的。

量子多体系统的资历。I.单壳层中的相同粒子

Seniority in quantum many-body systems. I. Identical particles in a single shell

本文讨论了多体系统中的资历量子数。分析是同时进行玻色子和费米子，但仅限于占据一个单一的壳相同的粒子。本文的重点是{ \em partial}守恒的可能性，它是自旋为9/2的费米子特有的性质，但在任何自旋的相互作用玻色子系统中普遍存在。资历的部分守恒是资历异构体存在的基础，经常在半幻核中观察到，也引起了特殊的选择规则在单核子转移反应。

对Chong Qi的“半幻核中部分守恒”的评论

Comment on "Partial conservation of seniority in semi-magic nuclei" by Chong Qi

指出该综述错误表述了作者论文的部分内容，并遗漏了重要部分。

Partial conservation of seniority and its unexpected influence on E2 transitions in $g_{9/2}$ nuclei

There exist two uniquely defined $v=4$ states in systems within a $j=9/2$ subshell, which automatically conserve seniority and do not mix with other states. Here I show that the partial conservation of seniority plays an essential role in our understanding of the electric quadrupole transitions of the semimagic nuclei involving $j=9/2$ subshells, including the long-lived $8^{+}$ isomer in $^{94}$Ru. The effects of configuration mixing from neighboring subshells on the structure of those unique states are analysed. It is shown that a sharp transition from pure seniority coupling to a significan…

Is Seniority a Partial Dynamic Symmetry in the First $νg_{9/2}$ Shell?

The low-lying structures of the midshell $νg_{9/2}$ Ni isotopes $^{72}$Ni and $^{74}$Ni have been investigated at the RIBF facility in RIKEN within the EURICA collaboration. Previously unobserved low-lying states were accessed for the first time following $β$ decay of the mother nuclei $^{72}$Co and $^{74}$Co. As a result, we provide a complete picture in terms of the seniority scheme up to the first $(8^+)$ levels for both nuclei. The experimental results are compared to shell-model calculations in order to define to what extent the seniority quantum number is preserved in the first neutron $…

Manifestation of the Berry phase in the atomic nucleus $^{213}$Pb

The neutron-rich $^{213}$Pb isotope was produced in the fragmentation of a primary 1 GeV $A$ $^{238}$U beam, separated in FRS in mass and atomic number, and then implanted for isomer decay $γ$-ray spectroscopy with the RISING setup at GSI. A newly observed isomer and its measured decay properties indicate that states in $^{213}$Pb are characterized by the seniority quantum number that counts the nucleons not in pairs coupled to angular momentum $J=0$. The conservation of seniority is a consequence of the Berry phase associated with particle-hole conjugation, which becomes gauge invariant and t…