N-]DELTA(1232) E2-TRANSITION AND SIEGERTS THEOREM

Until now, calculations of the E2 amplitude in the N --> Delta transit ion using the spatial current operator have differed considerably from those using the one-body charge operator and Siegert's theorem. We sh ow that this difference is almost entirely explained by spatial two-bo dy exchange currents consistent with the chosen quark-quark potentials . These were not explicitly included in previous comparisons. Furtherm ore, using Siegert's theorem we find that the main contribution to the E2 amplitude comes from a two-quark spin-flip mechanism originating f rom pion and gluon degrees of freedom in the charge operator. Our resu lts provide insight into the microscopic origin of the intrinsic defor mation of the nucleon. [S0556-2813(98)00710-9].