Regge pole and cut model of pion--nucleon charge exchange

The reaction π⁻p→π⁰n is described quantitatively in a model involving a nonsense-choosing ρ Regge pole modified by a mainly imaginary and spin-nonflip ρ⊗P-type Regge cut. The details are determined with the aid of continuous-moment finite-energy sum rules, as well as scattering data. The Regge cut is found to have peaked t dependence and approximately evasive behavior at t=0. This feature (in addition to its phase and spin coupling) disagrees strongly with predictions of conventional Regge-cut models. Some implications are mentioned.