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arXiv · 2210.16929

Muonic-Atom Spectroscopy and Impact on Nuclear Structure and Precision QED Theory

Aldo Antognini·Sonia Bacca·Andreas Fleischmann·Loredana Gastaldo·Franziska Hagelstein·Paul Indelicato·Andreas Knecht·Vadim Lensky·Ben Ohayon·Vladimir Pascalutsa·Nancy Paul·Randolf Pohl·Frederik Wauters
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Abstract

Recent progress in laser and x-ray spectroscopy of muonic atoms offers promising long-term possibilities at the intersection of atomic, nuclear and particle physics. In muonic hydrogen, laser spectroscopy measurements will determine the ground-state hyperfine splitting (HFS) and additionally improve the Lamb shift by a factor of 5. Precision spectroscopy with cryogenic microcalorimeters has the potential to significantly improve the charge radii of the light nuclei in the $Z=3-8$ range. Complementary progress in precision should be achieved on the theory of nucleon- and nuclear-structure effects. The impact of this muonic-atom spectroscopy program will be amplified by the upcoming results from H and He$^+$ spectroscopy, simple molecules such as HD$^+$ and Penning trap measurements. In this broader context, one can test ab-initio nuclear theories, bound-state QED for two- or three-body systems, and determine fundamental constants, such as the Rydberg ($R_\infty$) and the fine-structure ($\alpha$) constants.

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Aldo Antognini, Sonia Bacca, Andreas Fleischmann, Loredana Gastaldo, Franziska Hagelstein, Paul Indelicato, Andreas Knecht, Vadim Lensky, Ben Ohayon, Vladimir Pascalutsa, Nancy Paul, Randolf Pohl, Frederik Wauters. 2022-10-30. Muonic-Atom Spectroscopy and Impact on Nuclear Structure and Precision QED Theory. https://arxiv.org/abs/2210.16929

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