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

TL;DR

This paper analyzes how Lorentz and CPT symmetry violations could affect neutron and storage-ring EDM experiments, providing a framework to interpret measurements and set new limits on symmetry-breaking coefficients.

Contribution

It develops a theoretical framework linking EDM measurements to SME coefficients, enabling the first constraints on certain Lorentz-violating parameters.

Findings

Derived leading-order Lorentz and CPT violation effects in neutron EDM experiments.

Extended the BMT equation to include Lorentz-violating effects in storage-ring experiments.

Established explicit links between measured EDMs and SME coefficients for future constraints.

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.