Regge Poles with Absorptive-Correction Cuts and Exchange Degeneracy in the Reactionπ−p→ηn

Abstract

A Regge-pole model with absorptive corrections is used to fit the differential cross sections for the reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}\ensuremath{\eta}n$. This model, unlike the pure Regge-pole ${A}_{2}$-exchange model, also predicts a nonzero polarization. Exchange degeneracy is assumed for residues and trajectory. Thus, previous work on $\ensuremath{\pi}N$ scattering and ${A}_{2}$ scattering is used to fix the trajectory of the ${A}_{2}$ and its residue functions. $S{U}_{3}$ is also used to determine the size of the residues. Only a small amount of $S{U}_{3}$ breaking (10%) is needed to fit the data.