Analysis of Pion Photoproduction in the Second Resonance Region

Abstract

A phenomenological analysis is made of the pion photoproduction data in the energy range $535<\mathrm{}{E}_{\gamma }<850\mathrm{}$ MeV. The analysis is based on the pion-nucleon phase-shift analyses using a generalized isobar model. The Watson theorem for the elastic pion-nucleon partial waves is imposed. $\eta$ photoproduction data in the same energy range is also analyzed using an effective range expansion of the $K$ matrix. The nucleon-isobar electromagnetic couplings are determined.