The reaction e-+p→e-+p+πo has been studied in the π-N centre of mass range from 1130 to 1340 MeV/c2 by detecting the final proton in coincidence with the scattered electron. The four-momentum transfer to the pion-nucleon system was between 0.40 and 0.50 (GeV/c)2 and the polarisation of the exchanged virtual photon near unity. The proton angular distribution is analysed phenomenologically in terms of the multipoles M1+, E1+, S1+ contributing to the resonant partial wave and Eo+, So+ contributing to the s-wave background. The magnetic dipole excitation M1+ is shown to dominate the cross section but clear evidence is obtained for a significant contribution from the scalar multipole S1+.
ASJC Scopus subject areas
- Nuclear and High Energy Physics