QCD effective charges and the structure function F2 at small-x : higher twist effects

Abstract

We consider the effect of higher twist operators of the Wilson operator product expansion in the structure function F2(x, Q 2) at small-x, taking into account QCD effective charges whose infrared behavior is constrained by a dynamical mass scale. The higher twist corrections are obtained from the renormalon formalism. Our analysis is performed within the conventional framework of next-to-leading order, with the factorization and renormalization scales chosen to be Q 2. The infrared properties of QCD are treated in the context of the generalized double-asymptotic-scaling approximation. We show that the corrections to F2 associated with twist-four and twist-six are both necessary and sufficient for a good description of the deep infrared experimental data.