On the Role of the Running Coupling Constant in a Quark Model Analysis of T-odd TMDs

Abstract

We revisit the standard procedure to match non-perturbative models to perturbative QCD, using experimental data. The strong coupling constant plays a central role in the QCD evolution of parton densities. We will extend this procedure with a non-perturbative generalization of the QCD running coupling and use this new development to understand why perturbative treatments are working reasonably well in the context of hadronic models. Vice versa, this new procedure broadens the ways of analyzing the freezing of the running coupling constant.

Comments: To appear in the proceedings of the QCD Evolution Workshop: from collinear to non collinear case, April 8-9, 2011, JLab, Newport News, VA. ws-ijmpcs.cls included