N N-bar S-Wave Elastic Cross Section and Possible Bound States in a Constituent Quark Model

In the framework of a chiral constituent quark model, considering the contributions of π annihilation and one-gluon annihilation, the proton-antiproton s-wave elastic scattering cross section experimental data can be reproduced by adjusting properly one-gluon annihilation coupling constant. After fixing the model parameters, we perform a dynamical calculation for all possible s-wave nucleon–antinucleon states. The results show that there is no s-wave bound state as indicated by a strong enhancement at threshold of p p-bar in J/ψ and B decay. (the physics of elementary particles and fields)