${\gamma }^{\ast }p\to \Delta$ Form Factors in QCD

Abstract

We use local quark-hadron duality to estimate the purely nonperturbative soft contribution to the ${\gamma }^{\ast }p\to \Delta$ form factors. Our results are in agreement with existing experimental data. We predict that the ratio $G_E^{\ast }(Q^2)/G_M^{\ast }(Q^2)$ is small for all accessible $Q^2$, in contrast to the pQCD expectations that $G_E^{\ast }(Q^2)\to -G_M^{\ast }(Q^2)$.

7 pages, uuencoded compressed .ps-file. (Contribution to the International Symposium and Workshop on Particle Theory and Phenomenology at Iowa State University, Ames, May 22-24)