  In this talk the relation between the semiclassical approach and the concept
of diffractive parton densities is discussed. The proton rest frame calculation
is organized in a way that exhibits the hard partonic cross section and the
diffractive parton density as the two fundamental ingredients. The latter one
is a non-perturbative quantity which, in the present model, is explicitly given
by integrals of non-Abelian eikonal factors in the colour background field.

High Energy Physics - Phenomenology