Testing Strong-Field QED to Second Order in the Highly Correlated Atomic System Berylliumlike Pb 78 + by Electron-Ion Collision Spectroscopy

作者：S. Schippers, C. Brandau, S. Fuchs, M. Lestinsky, Shu-Xing Wang, Chunyu Zhang, N. R. Badnell, A Borovik, M. Fogle, V. Hannen, Z. Harman, P.‐M. Hillenbrand, E. Menz, Yang Zhang, Zoran Andelkovic, F. Herfurth, R. Heß, Anton Kalinin, C. Kozhuharov, C. Krantz, S. Litvinov, B. Lorentz, U. Spillmann, M. Steck, G. Vorobyev, D. Banaś, S. Fritzsche, Eva Lindroth, X. Ma, A. Müller, R. Schuch, A. Surzhykov, M. Trassinelli, K. Ueberholz, C. Weinheimer, Th. Stöhlker · 发表于：Physical Review Letters · 年份：2025 · DOI：10.1103/6j3v-lwxj · 被引用次数：7 · 研究领域：Atomic and Molecular Physics、Advanced Chemical Physics Studies、Cold Atom Physics and Bose-Einstein Condensates

A low-energy storage ring with an ultracold electron cooler has been coupled with a heavy-ion accelerator facilitating high-resolution electron-ion collision spectroscopy of the heaviest few-electron ions. In the present Letter resonant electron-ion recombination of berylliumlike Pb^{78+} ions was measured in the collision-energy range 9.3-16.5 eV and a value of 244.937(30) eV is derived for the Pb^{78+}(2s^{2} ^{1}S_{0}-2s2p ^{3}P_{1}) excitation energy. This result agrees with the most recent (less accurate) theoretical value of 244.942(52) eV [Malyshev et al., Phys. Rev. A 110, 062824 (2024)PLRAAN2469-992610.1103/PhysRevA.110.062824], which has been calculated by applying strong-field QED rigorously up to the second order. The present investigation suggests that further technical improvements can potentially increase the experimental accuracy by an order of magnitude.