近日，瑞士欧洲核子研究中心M. Au团队研究了一氟化锕的激光光谱和CP破坏灵敏度。相关论文于2025年12月17日发表在《自然》杂志上。

强核力在电荷共轭与宇称联合变换（CP）下的表观不变性，仍是现代物理学中一个悬而未决的问题。通过对重原子和分子开展精密实验，可借助对轻子、强子及原子核中永久电偶极矩和其他CP破缺特性的探测，为CP破坏提供严格约束。放射性分子已被提议作为此类探测的高灵敏探针，但迄今为止大多数此类分子的实验研究仍受限于技术条件。

研究组报道了一种气相锕系分子227AcF的制备与光谱研究。他们观测到了理论预测的基态最强电子跃迁，该跃迁对于高效读取破坏对称性相互作用至关重要。此外，研究组通过电子结构与核结构计算，确定了227AcF对各种CP破坏参数的敏感性，发现以1毫赫兹的精度开展的近期可实现实验，可将当前对CP破坏参数（超空间）的限制提升3个数量级。因此，该研究结果凸显了227AcF在极高灵敏度CP破坏探测中的潜力。

附：英文原文

Title: Laser spectroscopy and CP-violation sensitivity of actinium monofluoride

Author: Athanasakis-Kaklamanakis, M., Au, M., Kyuberis, A., Zlch, C., Gaul, K., Wibowo, H., Skripnikov, L., Lalanne, L., Reilly, J. R., Koszors, ., Bara, S., Ballof, J., Berger, R., Bernerd, C., Borschevsky, A., Breier, A. A., Chrysalidis, K., Cocolios, T. E., de Groote, R. P., Dorne, A., Dobaczewski, J., Fajardo Zambrano, C. M., Flanagan, K. T., Franchoo, S., Johnson, J. D., Garcia Ruiz, R. F., Hanstorp, D., Kujanp, S., Liu, Y. C., Lynch, K. M., McGlone, A., Mosyagin, N. S., Neyens, G., Nichols, M., Nies, L., Pastrana, F., Rothe, S., Ryssens, W., van den Borne, B., Wessolek, J., Wilkins, S. G., Yang, X. F.

Issue&Volume: 2025-12-17

Abstract: The apparent invariance of the strong nuclear force under combined charge conjugation and parity (CP) remains an open question in modern physics1,2. Precision experiments with heavy atoms and molecules can provide stringent constraints on CP violation via searches for effects due to permanent electric dipole moments and other CP-odd properties in leptons, hadrons and nuclei3. Radioactive molecules have been proposed as highly sensitive probes for such searches4, but experiments with most such molecules have so far been beyond technical reach. Here we report the production and spectroscopic study of a gas-phase actinium molecule, 227AcF. We observe the predicted strongest electronic transition from the ground state, which is necessary for efficient readout in searches of symmetry-violating interactions. Furthermore, we perform electronic- and nuclear-structure calculations for 227AcF to determine its sensitivity to various CP-violating parameters, and find that a realistic, near-term experiment with a precision of 1mHz would improve current constraints on the CP-violating parameter hyperspace by 3 orders of magnitude. Our results thus highlight the potential of 227AcF for exceptionally sensitive searches of CP violation.

DOI: 10.1038/s41586-025-09814-1

Source: https://www.nature.com/articles/s41586-025-09814-1