Nucleon Resonances and Mesons in Nuclei

The photoexcitation of nucleon resonances and their subsequent meson decay allows one to probe the structure of free and bound nucleons. A series of photonuclear experiments has been performed at the Mainz Microtron MAMI using the photon spectrometer TAPS. Differences in the photoproduction of mesons on the free proton and on nuclei are attributed to changes in the properties of hadrons in the nuclear medium. The results are discussed in the context of related experiments at other accelerators.