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arXiv · 2411.19872

Two-Photon Optical Ramsey-Doppler Spectroscopy of Positronium and Muonium

Evans Javary·Edward Thorpe-Woods·Irene Cortinovis·Marcus Mähring·Lucas de Sousa Borges·Paolo Crivelli
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Abstract

Positronium and muonium, as purely leptonic atoms without internal structure, provide ideal systems for high-precision tests of quantum electrodynamics (QED) and measurements of fundamental constants. However, the high velocities of these lightweight atoms complicate precision spectroscopy, particularly in the 1S-2S transition, due to transit time broadening and second-order Doppler shifts. To overcome these challenges, we propose a novel method combining two-photon Ramsey spectroscopy with a technique to correct the second-order Doppler shifts on an atom-by-atom basis. Additionally, this approach suppresses systematic effects of the AC Stark shift to a negligible level compared to the target precision. Simulations predict that for both positronium and muonium, this method could improve the measurement precision of the 1S-2S transition by more than two orders of magnitude compared to the current state of the art. This approach opens up new avenues for rigorous bound-state QED tests and searches for physics beyond the Standard Model.

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Evans Javary, Edward Thorpe-Woods, Irene Cortinovis, Marcus Mähring, Lucas de Sousa Borges, Paolo Crivelli. 2024-11-29. Two-Photon Optical Ramsey-Doppler Spectroscopy of Positronium and Muonium. https://arxiv.org/abs/2411.19872

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