Nonlinear $k_{\perp }$-factorization: a new paradigm for an in-nucleus hard QCD

Abstract

We review the origin, and salient features, of the breaking of the conventional linear $k_{\perp }$-factorization for an in-nucleus hard pQCD processes. A realization of the nonlinear $k_{\perp }$-factorization which emerges instead is shown to depend on color properties of the underlying pQCD subprocesses. We discuss the emerging universality classes and extend nonlinear $k_{\perp }$-factorization to AGK unitarity rules for the excitation of the target nucleus.

Comments: 16 pages, 2 figures, to be published in Preceedings of Gribov-75: Memorial Workshop On Quarks, Hadrons, And Strong Interactions, 22-24 May 2005, Budapest, Hungary