Dynamical theory for the P -wave pion-nucleon interaction

We present a dynamical theory of low energy P-wave ..pi..N interaction. The theory is an extension of the Chew-Low theory, with three additional features, namely, (1) inclusion of the full nucleon recoil effect, (2) inclusion of the Z graphs, and (3) inclusion of P11 channel inelasticity. The second feature is new in a P-wave theory based on the Low expansion. We are able to fit the P33 and the P11 phase shifts in the energy region 0