Off-shell unitarity and geometrical effects in deep-inelastic scattering and vector-meson electroproduction

Deep-inelastic scattering at low x and elastic vector meson production are considered on the basis of the off-shell extension of the s-channel unitarity. We discuss behavior of the structure function F_2(x,Q^2) at low x and the total cross-section of virtual photon-proton scattering and obtain, in particular, the dependence sigma^{tot}_{gamma^* p}\sim (W^2)^{lambda(Q^2)} where exponent lambda(Q^2) is related to the interaction radius of a constituent quark. The energy dependence of the total cross-section of gamma^*gamma^*-interactions is calculated. The explicit mass dependence of the exponent in the power energy behavior of the vector meson production in the processes of virtual photon interactions with a proton gamma^*p to Vp has been obtained. We also consider angular distributions at large momentum transfers.