Photoproduction of $η$-mesons off protons and deuterons

Abstract

An effective field theory with hadrons and photons is constructed, where the hadronic parameters are determined by fitting elastic $π$N scattering data. The predicted pion-induced $η$-production on the nucleon agrees well with the data. The hadronic model is then used to describe the final-state interaction in photoinduced processes. We present a consistent description of pion photoproduction in the E$_0^+$-channel and of the total cross sections for photoinduced $η$-production on the proton as well as on the deuteron.