近日，澳大利亚昆士兰大学的B. M. Roberts课题组取得一项新进展。经过不懈努力，他们探究了具有一个价电子的原子和离子的电偶极子跃迁振幅。相关研究成果已于2023年5月30日在国际知名学术期刊《物理评论A》上发表。

受到最近对几种碱金属原子和类似离子的测量结果的启发，该研究团队对K、Ca⁺、Rb、Sr⁺、Cs、Ba⁺、Fr和Ra⁺的电偶极子（E1）跃迁振幅进行了详细研究。这些研究对于原子宇称破缺、电偶极矩和极化率的研究具有重要意义。研究人员采用全阶相关势方法，对低能的s、p和d态之间的E1跃迁振幅进行了高精度计算。他们进行了可靠的误差分析，并将计算结果与多个已有的高精度实验结果进行了比较。研究发现两者之间非常吻合，偏差水平约为0.1%。

研究人员还将他们的结果与其他理论评估进行了比较，并讨论了不确定性分析的影响。此外，通过结合分支比的计算和最近的测量结果，他们成功地提取了Ca⁺、Sr⁺、Cs、Fr和Ra⁺多个E1振幅的高精度数值。

附：英文原文

Title: Electric-dipole transition amplitudes for atoms and ions with one valence electron

Author: B. M. Roberts, C. J. Fairhall, J. S. M. Ginges

Issue&Volume: 2023/05/30

Abstract: Motivated by recent measurements for several alkali-metal atoms and alkali-metal-like ions, we perform a detailed study of electric dipole (E1) transition amplitudes in K, Ca⁺, Rb, Sr⁺, Cs, Ba⁺, Fr, and Ra⁺, which are of interest for studies of atomic parity violation, electric dipole moments, and polarizabilities. Using the all-orders correlation potential method, we perform high-precision calculations of E1 transition amplitudes between low-lying s, p, and d states. We perform a robust error analysis, and compare our calculations to many amplitudes for which there are high-precision experimental determinations. We find excellent agreement, with deviations at the level of ～0.1%. We also compare our results to other theoretical evaluations, and discuss the implications for uncertainty analyses. Further, combining calculations of branching ratios with recent measurements, we extract high-precision values for several E1 amplitudes of Ca⁺, Sr⁺, Cs, Fr, and Ra⁺.

DOI: 10.1103/PhysRevA.107.052812

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.107.052812