# TNT Colloquium: Orbital Angular Momentum, Wandzura-Wilczek relations, and Generalized Transverse Momentum Distributions [Duke]

#### Tuesday, April 3, 2018 - 3:30pm

Wandzura Wilczek relations between matrix-elements of bilocal operators on thelight cone allow us to access the color forces among quarks and gluonsfrom off-forward scattering processes. I will present an analysis of the partontransverse momentum, $k_T$, substructure of these processesinvolving Generalized Parton Distributions (GPDs). I will focus, in particular,on three helicity configurations that can be detected analyzing specific spinasymmetries: two correspond to longitudinal proton polarization and areassociated with quark orbital angular momentum and spin-orbit correlations; thethird, obtained for transverse proton polarization, is a generalization of therelation obeyed by the g2 structure function from inclusive polarizedscattering. An additional relation connecting the off-forward extension of theSivers function to an off-forward quark-gluon-quark term, known asthe Qiu-Sterman term, will also be discussed.