Quark–pion coupling strength and ground state baryon spectra in a chiral potential model

Abstract

Chiral symmetry is incorporated into a relativistic independent-quark model with a square root confining potential and the quark–pion coupling strength, Gqqπ for quarks in a nucleon is estimated. The values of (Gqqπ2/4π) obtained with the approximation of a point pion as well as finite size pion are quite comparable with those estimated earlier by other researchers. Under the assumption that the baryon is an assembly of independent quarks confined in a first approximation by the square root potential that represents the nonperturbative gluon interactions, the model is also adopted to study the ground-state baryon spectrum taking into account perturbatively the contribution of the residual quark–pion coupling and that of the quark–gluon coupling in the baryon over and above the necessary center-of-mass correction. The physical masses of the ground state baryons calculated with the quark–gluon coupling constant αc = 0.227 agree reasonably well with experimental data.