Collinear laser spectroscopy measurements were performed on $^{69,71,73}$Ge isotopes ($Z = 32$) at ISOLDE-CERN. The hyperfine structure of the $4s^2 4p^2 \, ^3P_1 \rightarrow 4s^2 4p 5s \, ^3P_1^o$ transition of the germanium atom was probed with laser light of 269 nm, produced by combining the frequency-mixing and frequency-doubling techniques. The hyperfine fields for both atomic levels were calculated using state-of-the-art atomic relativistic Fock-space coupled-cluster calculations. A new $^{73}$Ge quadrupole moment was determined from these calculations and previously measured precision hyperfine parameters, yielding $Q_{\rm s}$ = $-$0.198(4) b, in excellent agreement with the literature value from molecular calculations. The moments of $^{69}$Ge have been revised: $\mu$ = +0.920(5) $\mu_{N}$ and $Q_{\rm s}$= +0.114(8) b, and those of $^{71}$Ge have been confirmed. The experimental moments around $N = 40$ are interpreted with large-scale shell-model calculations using the JUN45 interaction, revealing rather mixed wave function configurations, although their $g$-factors are lying close to the effective single-particle values. Through a comparison with neighboring isotones, the structural change from the single-particle nature of nickel to deformation in germanium is further investigated around $N = 40$.

中文翻译：

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N=40附近锗同位素的核矩

在 ISOLDE-CERN 对 $^{69,71,73}$Ge 同位素 ($Z = 32$) 进行共线激光光谱测量。锗原子的$4s^2 4p^2 \, ^3P_1 \rightarrow 4s^2 4p 5s \, ^3P_1^o$跃迁的超精细结构是用269 nm的激光探测的，通过结合频率-混频和倍频技术。两个原子水平的超精细场是使用最先进的原子相对论 Fock 空间耦合簇计算来计算的。一个新的 $^{73}$Ge 四极矩是从这些计算和先前测量的精确超精细参数中确定的，产生 $Q_{\rm s}$ = $-$0.198(4) b，与来自分子的文献值非常一致计算。修正了 $^{69}$Ge 的矩：$\mu$ = +0.920(5) $\mu_{N}$ 和 $Q_{\rm s}$= +0.114(8) b，以及$^{71}$Ge 的已确认。使用 JUN45 相互作用通过大规模壳模型计算解释 $N = 40$ 附近的实验矩，揭示了相当混合的波函数配置，尽管它们的 $g$ 因子接近有效的单粒子值。通过与邻近同位素的比较，进一步研究了在 $N = 40$ 附近从镍的单粒子性质到锗的变形的结构变化。