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Photoproduction of neutral pions from nuclei (carbon, calcium, niobium, lead) has been studied for incident-photon energies from 200 MeV to 800 MeV with the TAPS detector using the Glasgow photon tagging spectrometer at the Mainz MAMI accelerator. Data were obtained for the inclusive photoproduction of neutral pions and the, partial channels of quasifree single-pi(0), double-pi(0), and pi(0)pi(+/-) photoproduction. They have been analyzed in terms of the in-medium behavior of nucleon resonances and the pion-nucleus interaction. They are compared to earlier measurements from the deuteron and to the predictions of a Boltzmann-Uehling-Uhlenbeck (BUU) transport model for photon-induced pion production from nuclei.

The photoproduction of eta-mesic He-3 has been investigated using the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI. The total inclusive cross section for the reaction gamma(3)He-->etaX has been measured for photon energies from threshold to 820 MeV. The total and angular differential coherent eta cross sections have been extracted up to energies of 745 MeV. A resonancelike structure just above the eta production threshold with an isotropic angular distribution suggests the existence of a resonant quasibound state. This is supported by studies of a competing decay channel of such a quasibound eta-mesic nucleus into pi(0)pX. A binding energy of (-4.4+/-4.2) MeV and a width of (25.6+/-6.1) MeV is deduced for the quasibound eta-mesic state in He-3.

The reaction gammap-->pi(0)gamma(')p has been measured with the TAPS calorimeter at the Mainz Microtron accelerator facility MAMI for energies between roots=1221-1331 MeV. The cross section's differential in angle and energy have been determined for the photon gamma(') in three bins of the excitation energy. This reaction channel provides access to the magnetic dipole moment of the Delta(+)(1232) resonance and, for the first time, a value of mu(Delta)(+)=[2.7(-1.3)(+1.0)(stat)+/-1.5(syst)+/-3(theor)]mu(N) has been extracted.