Rescattering effects in coherent pion photoproduction on the deuteron in the $Δ$ resonance region

Abstract

Within a dynamical model, rescattering effects are studied in coherent pion photoproduction on the deuteron in the $Δ$(1232) resonance region. The model consists of a system of coupled equations for the N$Δ$, NN$π$ and NN channels. Pion rescattering leads in general to a significant reduction of total and differential cross sections resulting in a better description of experimental data. Only a few polarization observables are sensitive to rescattering effects. In particular $T_{20}$ allows an analysis of the reaction mechanism for specific kinematics. The question how rescattering affects the sensitivity to the E2 excitation of the $Δ$ resonance is also studied.