1209.0682 (Thomas Gehrmann et al.)

Transverse parton distribution functions at next-to-next-to-leading
order: the quark-to-quark case    [PDF]

Thomas Gehrmann, Thomas Lübbert, Li Lin Yang

We present a calculation of the perturbative quark-to-quark transverse parton distribution function at next-to-next-to-leading order based on a gauge invariant operator definition. We demonstrate for the first time that such a definition works beyond the first non-trivial order. We extract from our calculation the coefficient functions relevant for a next-to-next-to-next-to-leading logarithmic $Q_T$ resummation in a large class of processes at hadron colliders.

View original: http://arxiv.org/abs/1209.0682