PROTON POLARIZATION IN THE P((E)OVER-RIGHT-ARROW,E'(P)OVER-RIGHT-ARROW)PI-0 REACTION AND THE MEASUREMENT OF QUADRUPOLE COMPONENTS IN THE N-TO-DELTA-TRANSITION

The recoil proton polarization in the pi(0) production off the proton with longitudinally polarized electron beam has been studied as a mean s to measure quadrupole components in the N to Delta transition. On to p of the Delta resonance a high sensitivity to a possible Coulomb quad rupole excitation is found in parallel kinematics. The ratio of S1+/M1 + multipole amplitudes can be determined from the ratio of the two in- scattering-plane recoil proton polarization components. Avoiding the a bsolute measurement of the polarizations, such a ratio allows small ex perimental uncertainties. Furthermore, the electron helicity independe nt proton polarization component enables the characterization of reson ant and non-resonant pieces.