Baryon Mass Splitting in a Boson-Fermion Model

Abstract

A model is proposed in which a baryon consists of a boson and fermion deeply bound in a potential. The fermion can be regarded as a quark and the boson as a bound state of two quarks. In the model, the mass splitting of the different isospin multiplets among the baryons arises partly from mass splittings within the boson and fermion multiplets and partly from a symmetry-breaking interaction. The isospin-conserving mass splittings within the boson and fermion multiplets, as well as the symmetry-breaking interaction, are assumed to be proportional to the hypercharge. Under the assumption that these mass splittings and symmetry-breaking interactions are small, it is found that the seven baryon mass splittings which conserve isospin are given in terms of four parameters, and that the Gell-Mann-Okubo mass formula holds. Some effects of representation mixing are considered.