Meson photoproduction in the first and second resonance region
نویسنده
چکیده
The study of baryon resonances via meson photoproduction reactions on the free proton and on nucleons in the nuclear medium is discussed. Special emphasis is laid on the production of neutral mesons which due to the suppression of nonresonant backgrounds are particularly well suited for the study of excited states of the nucleon. Experiments carried out during the last ten years with the TAPSdetector at the Mainz Microtron (MAMI) have very significantly contributed to a detailed investigation of the low lying nucleon resonances P33(1232), D13(1520) and S11(1535). The most recent results from single and double pion production and from η-photoproduction are summarised.
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