近日，德国达姆施塔特工业大学Wilfried Nörtershäuser团队研究了加速器产氢208Bi82+的储存环激光光谱。2025年4月28日，《自然—物理学》杂志发表了该项成果。
量子电动力学已经过测试，在轻质量系统中的精度低于万亿分之一。然而，在装有大量核电荷的重质量系统中进行的测试尚未达到类似的精度。研究组报告了放射性氢（如208Bi82+）在1s基态中的超精细结构分裂。研究组在核反应中产生了同位素，并将光束注入储存环中，对105个Bi82+离子的样品进行激光光谱分析，这些离子只有一个剩余的电子，并经历了极端的磁场强度。
他们对超精细分裂的结果与基于量子电动力学计算和从209Bi和208Bi中性原子激光光谱中提取的超精细结构异常率的经验处理相结合的最准确预测非常一致。这一成就为在强磁场中对量子电动力学进行最严格的测试铺平了道路，并证明了激光光谱对其他低产量外来离子的可行性。
附：英文原文
Title: Storage-ring laser spectroscopy of accelerator-produced hydrogen-like 208Bi82+
Author: Horst, Max, Andelkovic, Zoran, Brandau, Carsten, Chen, Rui Jiu, Freire Fernndez, David, Geppert, Christopher, Glorius, Jan, Hannen, Volker, He, Regina, Imgram, Phillip, Klammes, Sebastian, Knig, Kristian, Leckenby, Guy, Litvinov, Sergey, Litvinov, Yury A., Lorentz, Bernd, Meisner, Johann, Mohr, Konstantin, Mller, Patrick, Passon, Stephan, Ratajczyk, Tim, Rausch, Simon, Robach, Jon, Snchez, Rodolfo, Sanjari, Shahab, Sidhu, Ragandeep Singh, Spillmann, Uwe, Steck, Markus, Sthlker, Thomas, Ueberholz, Ken, Weinheimer, Christian, Winters, Danyal, Nrtershuser, Wilfried
Issue&Volume: 2025-04-28
Abstract: Quantum electrodynamics has been tested to accuracies below the parts-per-trillion level in light-mass systems. However, tests in heavy-mass systems with a large nuclear charge have not yet reached similar accuracy. Here we report the hyperfine-structure splitting in the 1s ground state of radioactive hydrogen-like 208Bi82+. We produced the isotope in a nuclear reaction and injected the beam into a storage ring to perform laser spectroscopy on samples of 105 ions of Bi82+ that have only a single remaining electron, which experiences extreme magnetic-field strengths. Our result for the hyperfine splitting is in excellent agreement with the most accurate prediction based on a combination of quantum electrodynamics calculations with an empirical treatment of the hyperfine-structure anomaly ratio extracted from laser spectroscopy on neutral atoms of 209Bi and 208Bi. This achievement paves the way for the most stringent test of quantum electrodynamics in strong magnetic fields and demonstrates the feasibility of laser spectroscopy on other exotic ions with low production yields.
DOI: 10.1038/s41567-025-02885-x
Source: https://www.nature.com/articles/s41567-025-02885-x