Global analysis of the negative parity non-strange baryons in the 1/Nc expansion

TL;DR

This paper performs a comprehensive analysis of negative parity non-strange baryons using the 1/Nc expansion, examining masses, decay widths, and photo-couplings to understand state compositions and test model assignments.

Contribution

It provides a detailed determination of mixing angles and supports the assignment of nucleon states to the SU(4) x O(3) multiplet based on updated data and a global analysis approach.

Findings

Preferred assignment of nucleon states to the SU(4) x O(3) multiplet.

Determined mixing angles for spin 1/2 and 3/2 states.

Updated analysis with new input data.

Abstract

A global study of the negative parity non-strange baryon observables is performed in the frame- work of the 1/Nc expansion. Masses, partial decay widths and photo-couplings are simultaneously analyzed. A main objective is to determine the composition of the spin 1/2 and 3/2 nucleon states, which come in pairs and involve two mixing angles which can be determined and tested for consistency by the mentioned observables. The issue of the assignment of those nucleon states to the broken SU(4) x O(3) mixed-symmetry multiplet is studied in detail, with the conclusion that the assignment made in the old studies based on the non-relativistic quark model is the preferred one. In addition, the analysis involves an update of the input data with respect to previous works.