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arXiv · 2601.08899

Lorentz and CPT Tests in Neutron and Storage-Ring EDM Experiments

Abstract

We investigate Lorentz- and CPT-violating effects in neutron and storage-ring electric dipole moment (EDM) experiments within the framework of the Standard-Model Extension (SME). For neutron EDM experiments, perturbation theory is applied to derive leading-order contributions to the spin precession frequency arising from Lorentz and CPT violation. For storage-ring experiments, a generalized Bargmann-Michel-Telegdi equation is used to determine the corresponding spin-precession modifications. The analysis establishes explicit correspondences between measured EDMs and specific SME coefficients, providing a basis for setting the first limits on several previously unconstrained coefficients for Lorentz violation in future studies.

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Yunhua Ding. 2026-01-13. Lorentz and CPT Tests in Neutron and Storage-Ring EDM Experiments. https://arxiv.org/abs/2601.08899

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