Bounds on Lorentz and CPT violation from the $1S$-$2P$ transition in antihydrogen

TL;DR

This paper derives a model for Lorentz and CPT violation effects on antihydrogen's spectral lines, using recent experimental data to set first constraints on multiple violation coefficients and highlighting the importance of diverse transition measurements.

Contribution

It introduces a model for Lorentz and CPT violation in antihydrogen spectroscopy and establishes the first experimental constraints on 26 violation coefficients.

Findings

First constraints on 26 Lorentz and CPT violation coefficients.

Agreement of antihydrogen transition measurements with Standard Model predictions.

Highlighting the importance of measuring multiple transitions for CPT tests.

Abstract

A model for the Lorentz- and CPT-violating frequency shift for the antihydrogen $1S$-$2P$ transition in the presence of an external magnetic field is derived. Using the recent measurement of the $1S$-$2P$ transition frequency in antihydrogen by the ALPHA collaboration, which they demonstrated agrees with predictions from the Standard Model of particle physics, we establish the first constraints on 26 effective coefficients for Lorentz and CPT violation. Also, this work uses these results to underscore the value of measuring multiple transition frequencies to test CPT symmetry through antihydrogen spectroscopy, emphasizing the advantages of transitions involving states with higher angular momentum.