Momentum projection of the nucleon in the colour-dielectric model

Abstract

We use the method of Lübeck et al. to project the mean-field solutions of the colour-dielectric model onto momentum eigenstates, so removing the spurious c.m. motion. A coherent state is used to provide a quantum description of the colour-dielectric field. In addition the nucleon mass is varied after projection. A range of parameter sets is considered, but we find that this technique is only appropriate to those with a simple quadratic potential. These results show a significant improvement over the mean-field approximation, the product of the proton mass and r.m.s. radius being within 30% of its observed value. Projection of solutions for a double-minimum potential results in a mass-radius project which is an order of magnitude too small, due to the high mean-square momentum in the soliton approximation. We conclude that the MFA is not a good starting point for parameter sets of this kind.