$\Lambda$ and $\Sigma$ Excitations and the Quark Model

TL;DR

This paper reviews the spectrum of Lambda and Sigma hyperon excitations, compares experimental data with quark models, and discusses their SU(3) structure and relations to nucleon and delta resonances.

Contribution

It provides a comprehensive review of hyperon resonances, compares them with quark model predictions, and explores their SU(3) and SU(6) symmetry properties.

Findings

Seven Lambda states are identified as SU(3) singlets.

The hyperon spectrum aligns with certain quark model predictions.

SU(3) and SU(6) symmetry relations are examined in hyperon decays.

Abstract

The spectrum of $\Lambda$ and $\Sigma$ excitations is reviewed taking into account (nearly) all hyperon resonances which were seen in early analyses or in one of the recent partial-wave analyses. The spectrum is compared with the old Isgur-Karl model and the Bonn model. These models allows us to discuss the SU(3) structure of the observed resonances. The SU(3) decomposition is compared with SU(6) relations between the different decay modes. Seven $\Lambda$ states are proposed to be classified as SU(3) singlet states. The hyperon spectrum is compared with the spectrum of $N$ and $\Delta$ resonances.