SU(3)-breaking corrections to the baryon-octet magnetic moments in chiral perturbation theory

TL;DR

This paper calculates baryon magnetic moments using covariant chiral perturbation theory, incorporating SU(3) breaking effects and comparing different renormalization schemes to improve agreement with experimental data.

Contribution

It introduces a covariant approach with extended-on-mass-shell renormalization to better account for SU(3) breaking in baryon magnetic moments.

Findings

Improved fit to experimental magnetic moments with SU(3) breaking effects

Comparison shows differences between covariant and heavy-baryon approaches

Identification of key loop contributions affecting results

Abstract

We report a calculation of the baryon magnetic moments using covariant chiral perturbation theory within the extended-on-mass-shell renormalization scheme including intermediate octet and decuplet contributions. By fitting the two available low-energy constants, we improve the Coleman-Glashow description of the data when we include the leading SU(3) breaking effects coming from the lowest-order loops. We compare with previous attempts at the same order using heavy-baryon and covariant infrared chiral perturbation theory, and discuss the source of the differences.