Using a novel concept for efficient laser spectroscopy, the hyperfine splittings of three different atomic transitions in the long-lived isotopes ${}^{97-99}$Tc were investigated. Despite the refractory character of the element technetium, sample sizes as low as ${10}^{11}$ atoms were sufficient to achieve excellent signal-to-noise ratios at a spectroscopic line width of less than $100$,MHz. The obtained spectra were analyzed in detail, which results in a very good consistency for the extracted hyperfine parameters from the different transitions. The presented measurements provide the first hyperfine structure data for the isotopes ${}^{97,98}$Tc from which, in combination with the known nuclear moments of ${}^{99}$Tc, their nuclear magnetic dipole and electric quadrupole moments were extracted. In addition, the experimental data confirm the predicted nuclear spin of ${}^{98}$Tc to $I=6$. Supported by atomic Multi-Configuration Dirac-Hartree-Fock (MCDHF) calculations the observed isotope shifts were investigated and the changes in mean square charge radii were determined.

中文翻译：

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用于高分辨率激光光谱的新型激光离子源中97、98、99Tc的超精细结构研究

使用有效激光光谱的新概念，长寿命同位素中三个不同原子跃迁的超精细分裂 ${}^{97-99}$对TC进行了调查。尽管tech元素具有耐火性，但样品量低至${10}^{11}$ 原子足以在光谱线宽小于的情况下获得出色的信噪比 $100$，MHz。对获得的光谱进行了详细分析，这为从不同过渡中提取的超精细参数提供了非常好的一致性。提出的测量结果提供了同位素的第一超细结构数据${}^{97，98}$Tc，结合已知的核矩 ${}^{99}$提取了TC，它们的核磁偶极矩和电四极矩。此外，实验数据证实了预测的核自旋${}^{98}$到 $\mathrm{一世}=6$。在原子多构狄拉克-哈特里-福克（MCDHF）计算的支持下，对观察到的同位素位移进行了研究，并确定了均方电荷半径的变化。