Year: 2002
Type: article
Abstract: We consider the perturbative description of saturation based on the nonlinear QCD evolution equation of Balitsky and Kovchegov. Although the nonlinear corrections lead to saturation of the scattering amplitude locally in impact parameter space, we show that they do not unitarize the total cross section. The total cross section for the scattering of a strongly interacting probe on a hadronic target is found to grow exponentially with rapidity $t=\mathrm{ln}{(s/s}_{0}),$ $\ensuremath{\sigma}\ensuremath{\propto}\mathrm{exp}{({\ensuremath{\alpha}}_{s}{N}_{c}/2\ensuremath{\pi})\ensuremath{\epsilon}t}$ where $\ensuremath{\epsilon}$ is a number of order unity. The origin of this violation of unitarity is the presence of long range Coulomb fields away from the saturation region. The growth of these fields with rapidity is not tempered by the nonlinearity of the Balitsky-Kovchegov equation.
Authors: Alexander Kovner, Urs Achim Wiedemann
Institution: University of Plymouth
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2031004791