Superconvergence Relations and Possible New Resonances in Pion-Baryon Scattering

Superconvergence relations for the B(+) amplitudes at t=0 for pion-baryon scattering are well saturated by low-lying resonances, except for the one for the π-Σ scattering. This remarkable disparity suggests that some new π-Σ resonances may exist. From the unitarity condition on the p-wave π-Σ scattering, it is shown that the resonances, if any, are in (I, JP)=(0, 32+) and (2, 32+) states.