Q2 dependence of diffractive vector meson electroproduction -: art. no. 014022

We give a general formula for the cross section for diffractive vector meson electroproduction, gamma*p-->Vp. We first calculate diffractive q (q) over bar production, and then use parton-hadron duality by projecting out the J(P) = 1(-) state in the appropriate mass interval. We compare the Q(2) dependence of the cross section for the diffractive production of rho and J/psi mesons with recent DESY HERA data. We include the characteristic Q(2) dependence associated with the use of the skewed gluon distribution. We give predictions for sigma(L)/sigma(T) for both rho and J/psi production.