Quantum Electrodynamics in Strong Electromagnetic Fields: Substate Resolved K$\alpha$ Transition Energies in Helium-like Uranium

Philip Pfäfflein; Günter Weber; Steffen Allgeier; Zoran Andelkovic; Sonja Bernitt; Andrey I. Bondarev; Alexander Borovik; Louis Duval; Andreas Fleischmann; Oliver Forstner; Marvin Friedrich; Jan Glorius; Alexandre Gumberidze; Christoph Hahn; Daniel Hengstler; Marc Oliver Herdrich; Frank Herfurth; Pierre-Michel Hillenbrand; Anton Kalinin; Markus Kiffer; Felix Martin Kröger; Maximilian Kubullek; Patricia Kuntz; Michael Lestinsky; Yuri A. Litvinov; Bastian Löher; Esther Babette Menz; Tobias Over; Nikolaos Petridis; Stefan Ringleb; Ragandeep Singh Sighu; Uwe Spillmann; Sergiy Trotsenko; Andrzej Warczak; Binghui Zhu; Christian Enss; Thomas Stöhlker

doi:10.1103/physrevlett.134.153001

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arXiv · 2407.04166

Quantum Electrodynamics in Strong Electromagnetic Fields: Substate Resolved K$\alpha$ Transition Energies in Helium-like Uranium

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Abstract

Using novel metallic magnetic calorimeter detectors at the CRYRING@ESR, we recorded X-ray spectra of stored and electron cooled helium-like uranium (U$^{90+}$) with an unmatched spectral resolution of close to 90 eV. This allowed for an accurate determination of the energies of all four components of the K$\alpha$ transitions in U$^{90+}$. We find good agreement with state-of-the-art bound-state QED calculations for the strong-field regime. Our results do not support any systematic deviation between experiment and theory in helium-like systems, the presence of which was subject of intense debates in recent years.

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Philip Pfäfflein, Günter Weber, Steffen Allgeier, Zoran Andelkovic, Sonja Bernitt, Andrey I. Bondarev, Alexander Borovik, Louis Duval, Andreas Fleischmann, Oliver Forstner, Marvin Friedrich, Jan Glorius, Alexandre Gumberidze, Christoph Hahn, Daniel Hengstler, Marc Oliver Herdrich, Frank Herfurth, Pierre-Michel Hillenbrand, Anton Kalinin, Markus Kiffer, Felix Martin Kröger, Maximilian Kubullek, Patricia Kuntz, Michael Lestinsky, Yuri A. Litvinov, Bastian Löher, Esther Babette Menz, Tobias Over, Nikolaos Petridis, Stefan Ringleb, Ragandeep Singh Sighu, Uwe Spillmann, Sergiy Trotsenko, Andrzej Warczak, Binghui Zhu, Christian Enss, Thomas Stöhlker. 2024-07-04. Quantum Electrodynamics in Strong Electromagnetic Fields: Substate Resolved K$\alpha$ Transition Energies in Helium-like Uranium. https://doi.org/10.1103/physrevlett.134.153001

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