πN → MULTI-πN SCATTERING IN THE 1/N_c EXPANSION

Abstract

We extend the 1/Nc meson-baryon scattering formalism to πN → multi-πN case. We first show that the leading-order large Nc processes proceed through resonant intermediate states (e.g., ρN or π∆). We find that the pole structure of baryon resonances can be uniquely identified by their (non)appearance in ηN or mixed partial-wave π∆ final states.