$\pi N$ Scattering in the $\Delta(1232)$ Region in an Effective Field Theory

Abstract

We develop a generalized version of heavy-baryon chiral perturbation theory to describe pion-nucleon scattering in a kinematic domain that extends continuously from threshold to the delta-isobar peak. The $P$-wave phase shifts are used to illustrate this framework. We also compare our approach with those in the literature that concern the delta resonance.