The Chiral Quark-Sigma Model with Modified Logarithmic Potential for Nucleon Properties

Abstract

A modified logarithmic mesonic potential which based on some aspects of quantum chromodynamics (QCD) theory is investigated. The modified logarithmic mesonic potential is far from the singularity point which comes at vanishing of pion and sigma-meson contributions ( σ2 +π2 = 0 ) . The field equations have been solved in the mean-field approximation using the iteration method. The obtained results of nucleon properties are improved in comparison with the original quark-sigma model and other models. In particular, the nucleon and delta masses, the pion-nucleon coupling constant, and the sigma term are in good agreement with experimental data. In addition, A comparison with the recent quark models such as the extended Skyrme model and the perturbative quark model is discussed. We conclude that the modified logarithmic quark model successfully predicts nucleon properties and avoid difficulty that found in the previous works.