The E2/M1 and C2/M1 ratios and form factors in N -> Delta transitions

A partial wave analysis of pion photoproduction has been obtained in the fr amework of fixed-t dispersion relations valid from threshold up to 500 MeV. In the resonance region we have precisely determined the electromagnetic p roperties of the Delta (1232) resonance, in particular the E2/M1 ratio R-EM = (-2.5 +/- 0.1)%. For pion electroproduction recent experimental data fro m Mainz, Bates and JLab for Q(2) up to 4.0 (GeV/c)(2) have been analyzed wi th two different models, an isobar model (MAID) and a dynamical model. The E2/M1 ratios extracted with these two models show, starting from a small an d negative value at the real photon point, a clear tendency to cross zero, and become positive with increasing Q(2). This is a possible indication of a very slow approach toward the pQCD region. The C2/M1 ratio near the photo n point is found as R-SM(0) = (-6.5 +/- 0.5)%. At high Q(2) the absolute va lue of the ratio is strongly increasing, a further indication that pQCD is not yet reached.