Deep inelastic scattering data and the problem of saturation in small-x physics - art. no. 054010

We investigate the role of unitarization effects in virtual photon-proton ( gamma *p) interactions at small x. The q (q) over bar fluctuation of the in itial photon is separated into a small distance and a large distance compon ent and a model for the unitarization of each component is proposed. The Bo rn approximation for the small size component is calculated using QCD pertu rbation theory. A Reggeon diagram technique is used in order to obtain a se lf-consistent scheme for both the total gamma *p cross section and diffract ive production. The model gives a good description of DESY HERA data in the small-x region, with a single Pomeron of intercept 1.2.