On the High Energy Behaviour of The Total Cross Section in the QCD Dipole Model

Abstract

In this paper we perform a numerical study of the tranverse expansion of hadronic scattering amplitudes in the dipole picture of high energy QCD. We go beyond the mean field approximation by including fluctuations and also wave function saturation effects, and the evolution with both a fixed and a running coupling is investigated. We also study the nonperturbative aspects, and as has been predicted earlier, our results indicate that the Froissart-Martin bound is saturated once confinement effects are included in the evolution. Thus the total cross section increases proportional to the square of the logarithm of the cms energy. Furthermore it is seen that we obtain a reasonable value for the proportionality coefficient. The impact of saturation and non-leading effects on this coefficient is also studied.