QCD evolution of the transverse momentum dependent correlations

Abstract

We study the nonsinglet evolution for the twist-three quark-gluon correlation functions associated with the transverse momentum odd quark distributions. Different from that for the leading-twist quark distributions, these evolution equations involve more general twist-three functions beyond the correlation functions themselves. They provide important information on nucleon structure and can be studied in the semi-inclusive hadron production in deep inelastic scattering and Drell-Yan lepton pair production in the $pp$ scattering process.