Photo Reactions on the Deuteron in the Delta-Resonance

Photo disintegration of the deuteron and photo pionproduction on the deuteron are described in the region of the $\Delta$-resonance. The two reactions are unitarily coupled. A novel definition of electromagnetic exchange currents in the presence of pionproduction is given. Numerical predictions are done for spin-independent and spin-dependent observables of both reactions. The sensitivity of the results with respect to the nucleon-$\Delta$ transition current and with respect to the irreducible nucleon-$\Delta$ potential is studied.