Baryon magnetic moments: Symmetries and relations

TL;DR

This paper uses lattice QCD to compute octet baryon magnetic moments, exploring symmetries and relations at a symmetric quark mass point, revealing insights beyond traditional models.

Contribution

It introduces the first lattice QCD treatment of the Sigma-Lambda system and compares quark model predictions with large Nc limit results.

Findings

Quark model predictions are often favored over large Nc limit predictions.

Symmetries at the three-flavor symmetric point provide new insights into magnetic moments.

The study highlights the need for further calculations to understand magnetic moment patterns.

Abstract

Magnetic moments of the octet baryons are computed using lattice QCD in background magnetic fields, including the first treatment of the magnetically coupled Sigma-Lambda system. Although the computations are performed for relatively large values of the up and down quark masses, we gain new insight into the symmetries and relations between magnetic moments by working at a three-flavor mass-symmetric point. While the spin-flavor symmetry in the large Nc limit of QCD is shared by the naive constituent quark model, we find instances where quark model predictions are considerably favored over those emerging in the large Nc limit. We suggest further calculations that would shed light on the curious patterns of baryon magnetic moments.