Speaker
Description
A fundamental ingredient for phenomenological studies of the three-dimensional (3D) momentum structure of the nucleon is provided by matching relations. These relations constrain the functional form of 3D parton distributions by connecting them to their collinear counterparts. For quark transverse-momentum–dependent distributions (TMDs), matching relations are known at one-loop accuracy, including contributions up to twist-3. In contrast, for gluon distributions such relations have so far been established only at leading twist. In this talk, I will present new results for gluon TMDs at tree level and one loop, including twist-3 contributions. At tree level, I will discuss the matching relations for both T-even and T-odd distributions, incorporating the complete series of mass corrections. At one-loop accuracy, the main result is the derivation of a Wandzura–Wilczek–type relation for the gluon worm-gear T distribution.