Diffractive photon dissociation in the saturation regime from the Good-Walker picture

Combining the QCD dipole model with the Good-Walker picture, we formulate the diffractive dissociation of a photon of virtuality [Formula Presented] off a hadronic target, in the kinematical regime in which Q is close to the saturation scale and much smaller than the invariant mass of the diffracted system. We show how the formula obtained compares to the DESY HERA data and discuss what can be learned from such a phenomenology. In particular, we argue that the diffractive observables in these kinematics provide useful pieces of information on the saturation regime of QCD.