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arXiv · 2403.17763

CPT and Lorentz symmetry tests with hydrogen using a novel in-beam hyperfine spectroscopy method applicable to antihydrogen experiments

Lilian Nowak·Chloe Malbrunot·Martin C. Simon·Claude Amsler·Sergio Arguedas Cuendis·Sebastian Lahs·Andreas Lanz·Amit Nanda·Markus Wiesinger·Tim Wolz·Eberhard Widmann
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Abstract

We present a Rabi-type measurement of two ground-state hydrogen hyperfine transitions performed in two opposite external magnetic field directions. This puts first constraints at the level of 2.3 10^-21 GeV on a set of coefficients of the Standard Model Extension, which were not measured by previous experiments. Moreover, we introduce a novel method, applicable to antihydrogen hyperfine spectroscopy in a beam, that determines the zero-field hyperfine transition frequency from the two transitions measured at the same magnetic field. Our value, nu_0 = 1.420 405 751 63(63) GHz, is in agreement with literature at a relative precision of 0.44 ppb. This is the highest precision achieved on hydrogen in a beam, improving over previous results by a factor of 6.

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Lilian Nowak, Chloe Malbrunot, Martin C. Simon, Claude Amsler, Sergio Arguedas Cuendis, Sebastian Lahs, Andreas Lanz, Amit Nanda, Markus Wiesinger, Tim Wolz, Eberhard Widmann. 2024-03-26. CPT and Lorentz symmetry tests with hydrogen using a novel in-beam hyperfine spectroscopy method applicable to antihydrogen experiments. https://doi.org/10.1016/j.physletb.2024.139012

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