Theory of the High-Energy Peaks in Pion-Nucleon Cross Sections

An investigation is reported on whether the spectrum of high-energy peaks observed at 650, 950, and 1300 Mev in pi -p scattering can be explained in terms of the conventional low-energy pseudoscalar pi -N interaction. A Chew-Low formalism is outlined which predicts two isobars, or metastable states, of the nucleon that may be asseciated with the 950 and 1300 Mev peaks. (W.D.M.)