标题： 四面体形状和Lambda杂质效应在多维约束相对论Hartree-Bogoliubov模型的$^{80}$Zr中的影响 显示英文标题

标题： Tetrahedral shape and Lambda impurity effect in $^{80}$Zr with a multidimensionally constrained relativistic Hartree-Bogoliubov model

摘要： 本研究利用多维约束相对论Hartree-Bogoliubov模型，研究了$^{80}$锆中的四面体结构以及$^{81}_{~\Lambda}$锆中 ($\Lambda$) 杂质的影响。$^{80}$锆和$^{81}_{~\Lambda}$锆的基态均呈现出四面体构型，并伴随有长球形和轴向八极形状同分异构体。 我们的计算表明，当 $\Lambda$ 结合到 $^{80}$锆上时，变形参数 $\beta_{20}$、$\beta_{30}$ 和 $\beta_{32}$ 发生变化，但当 $\Lambda$ 占据 $p$轨道时，例外的是 $\beta_{32}$。 与这两种形状异构体相比，当占据$1/2^+[000](\Lambda_s)$或$1/2^-[110]$单粒子态时，$\Lambda$粒子在四面体状态下的结合能较弱。相反，对于处于四面体形状的$1/2^-[101]$态中的$\Lambda$粒子，结合能最强。此外，较大的$\Lambda$分离能不一定与$\Lambda$粒子和核芯的密度分布之间存在显著重叠相关，特别是在四面体超核的情况下。 显示英文摘要

摘要： This study investigates the tetrahedral structure in $^{80}$Zr and Lambda ($\Lambda$) impurity effect in $^{81}_{~\Lambda}$Zr using the multidimensionally constrained relativistic Hartree-Bogoliubov model. The ground states of both $^{80}$Zr and $^{81}_{~\Lambda}$Zr exhibit a tetrahedral configuration, accompanied by prolate and axial-octupole shape isomers. Our calculations reveal there are changes in the deformation parameters $\beta_{20}$, $\beta_{30}$, and $\beta_{32}$ upon $\Lambda$ binding to $^{80}$Zr, except for $\beta_{32}$ when $\Lambda$ occupies $p$-orbits. Compared to the two shape isomers, the $\Lambda$ particle exhibits weaker binding energy in the tetrahedral state when occupying the $1/2^+[000](\Lambda_s)$ or $1/2^-[110]$ single-particle states. In contrast, the strongest binding occurs for the $\Lambda$ particle in the $1/2^-[101]$ state with tetrahedral shape. Besides, a large $\Lambda$ separation energy may not necessarily correlate with a significant overlap between the density distributions of the $\Lambda$ particle and the nuclear core, particularly for tetrahedral hypernuclei.