Ξ and Ω baryons in the Skyrme model

The mass spectrum and magnetic moments of Ξ and Ω baryon resonances are investigated in the bound-state approach of the Skyrme model. The empirical hyperon spectrum shows that several hyperon resonances share a pattern of (approximately) equal mass spacings between the states of same spin but of opposite parity. It is found that this pattern can be explained mostly by the energy difference between the P-wave and S-wave kaons bound to the soliton. Although one cannot exclude the possibility that these states can be described as pion-hyperon resonances, the present approach predicts that Ξ(1620) and Ξ(1690) have J^P=1/2^-, while Ξ(1950) has J^P=1/2⁺. The differences with the quark model predictions for the Ξ and Ω baryon spectrum are pointed out. Several relations for the masses and magnetic moments of those resonances are also obtained.