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arXiv · 2507.07473

Demonstration of deuterium's enhanced sensitivity to symmetry violations governed by the Standard-Model Extension

Amit Nanda·Daniel Comparat·Olivier Dulieu·Sebastian Lahs·Chloe Malbrunot·Lilian Nowak·Martin C. Simon·Eberhard Widmann
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Abstract

We have performed hyperfine spectroscopy of two transitions in ground-state deuterium and searched for violations of CPT and Lorentz symmetry that would manifest as sidereal variations of the observed transition frequencies. Several nonrelativistic proton coefficients of the Standard-Model Extension framework have been addressed. The spin-independent coefficients with momentum power k=2,4 are constrained for the first time. Bounds on spin-dependent coefficients are improved by exploiting a sensitivity enhancement originating from the relative momenta of the nucleons in the deuteron. The best previous constraints by hydrogen maser measurements are surpassed by 4 and 14 orders of magnitude for coefficients with k=2 and 4, respectively.

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Amit Nanda, Daniel Comparat, Olivier Dulieu, Sebastian Lahs, Chloe Malbrunot, Lilian Nowak, Martin C. Simon, Eberhard Widmann. 2025-07-10. Demonstration of deuterium's enhanced sensitivity to symmetry violations governed by the Standard-Model Extension. https://doi.org/10.1103/dqvd-15q4

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