Baryon Spectra in the Framework of an Equivparticle Model

Based on an equivparticle model incorporating both confinement and leading-order perturbative interactions, we fit the model parameters to the experimental masses of \mathrmp , \mathrmn , \Lambda , and \Delta . It is found that the equivparticle model well reproduces the mass spectra of light baryons. Distinctive correlations of the confinement strength D, the strong coupling constant \alpha_\rms, and quark mass factor f with respect to the perturbative strength C are obtained, which can be well approximated by analytical formulae. The color-magnetic part of one-gluon-exchange interaction plays a significant role on the mass spectra of light baryons, which causes a mass gap of up to 300 MeV between baryons with spins J=1/2 and 3/2. By adopting different strong coupling constants for a pair of quarks with strangeness, the hyperon masses can be better described with the model parameters fitted to the masses of \Sigma and \Xi . The equivparticle model developed here with constrained parameter sets are then applicable to the investigation of exotic states such as \mathrmudQM nuggets, strangelets, and compact stars.