Chiral effective-field theory in the Delta(1232) region: II. radiative pion photoproduction

Abstract

We present a theoretical study of the radiative pion photoproduction on the nucleon (γ N π N γ') in the -resonance region, with the aim to determine the magnetic dipole moment (MDM) of the +(1232). The study is done within the framework of chiral effective-field theory where the expansion is performed (to next-to-leading order) in the δ power-counting scheme which is an extension of chiral perturbation theory to the -resonance energy region. We present the results for the absorptive part of the MDM, as well as perform a sensitivity study of the dependence of γ N π N γ' observables on the real part of the MDM. We find that an asymmetry for circular polarization of the photon beam may provide a model-independent way to measure the MDM.