Color Gauge Invariance in Hard Processes

Abstract

Within the theoretical framework we apply, a suggested origin for single spin asymmetries is the presence of gauge links in transverse momentum dependent distribution functions. Recently we found new gauge link structures in a number of hard processes. These structures need to be considered in the evolution of parton distribution functions and for establishing factorization.

Comments: One reference corrected, 4 pages and 2 figures. Presented at Light-Cone 2004