The helicity structure of the nucleon excitation spectrum Original Research Article

The helicity dependence of the total and partial photoproduction reaction channels has been measured for the first time in an energy range 200 MeV ≤ ν ≤ 800 MeV at MAMI using circularly polarized photons together with a longitudinally polarized proton target and a 4π detector system. The reaction View the MathML source is predominantly sensitive to the D13(1520) resonance and the data are used to adjust its parameters.