Hyperon resonances in the chiral bag model

We calculate the masses of low-lying negative-parity ${\Lambda }^{\mathrm{*}}$ and ${\Sigma }^{\mathrm{*}}$ in a chiral bag model with broken SU(2)⊗SU(2) realization of chiral symmetry. All relevant one-gluon-exchange and effective quark-quark one-pion-exchange diagrams are evaluated. We show why the spin-flavor contents of the hyperon resonances are different from that of a nonrelativistic quark model. In particular, we find that the Λ(1405) has almost no flavor-singlet component. The prescription used to project out the translational mode of the bag is tested for the simplest case.