The helicity dependence of the differential cross-section for the γd → πNN reactions has been measured for the first time in the Δ -resonance region. The measurement was performed with the large-acceptance detector DAPHNE at the tagged photon beam facility of the MAMI accelerator in Mainz. The data show that the main reaction mechanisms for the π±NN channels are the quasi-free Nπ processes on one bound nucleon with nuclear dynamics playing a minor role. On the contrary, for the π0 np channel nuclear mechanisms involving the reabsorption of the photoproduced π0 by the np pair have to be taken into account to reproduce the experimental data.
ASJC Scopus subject areas
- Nuclear and High Energy Physics