AI 中文总结
该研究针对原子系统的场移，提出了基于核参数的系统展开式，验证了其对类氢离子的有效性，计算了类碱金属系统的高阶修正并引入近似，表明高阶修正不影响金图线性。
AI 中文摘要
同位素之间的核电荷分布差异会导致原子光谱发生微小变化，这种现象被称为场移。尽管场移在很大程度上与核均方半径的变化成正比，但它也包含对核矩具有不同依赖关系的高阶贡献。在利用金图（King plots）寻找新物理时，必须了解这些贡献，因为它们会导致金图偏离线性。我们提出了一种用核参数表示的场移能的系统展开式，并通过对类氢离子的直接数值计算验证了其有效性。我们还计算了从类锂到类铷的类碱金属系统的主导阶和高阶场移修正，发现它们的比值几乎与离子电荷态无关，与对应的类氢1s比值在亚百分之一的水平上一致。受这一观察结果的启发，我们引入了一种近似方法，假设这些分数贡献与电子构型无关。我们证明，在该近似下，高阶场移修正不会对金图的非线性产生贡献。
英文摘要
Differences in nuclear charge distributions between isotopes lead to small changes in atomic spectra known as the field shift. While largely proportional to the change in the mean-square nuclear radius, the field shift also contains higher-order contributions with different dependencies on nuclear moments. Their knowledge is required in searches for new physics using King plots, as they can induce deviations from King-plot linearity. We present a systematic expansion of the field-shift energies in terms of nuclear parameters and test its validity against direct numerical calculations for H-like ions. We also compute leading- and higher-order field-shift corrections for alkali-like systems from Li-like to Rb-like ions, and find that their ratio is nearly independent of the ionic charge state, agreeing with the corresponding hydrogenic $1s$ ratios on a sub-percent level. Motivated by this observation, we introduce an approximation in which these fractional contributions are assumed to be independent of the electronic configuration. We show that within this approximation, higher-order field-shift corrections do not contribute to King-plot nonlinearities.
