Paper
Two-Loop Quark and Gluon Form Factors in Dimensional Regularisation
Authors
T. Gehrmann, T. Huber, D. Maitre
Abstract
We compute the two-loop corrections to the massless quark form factor and gluon form factor to all orders in the dimensional regularisation parameter . The two-loop contributions to the form factors are reduced to linear combinations of master integrals, which are computed in a closed form, expressed as -functions and generalised hypergeometric functions of unit argument. Using the newly developed HypExp-package, these can be expanded to any desired order, yielding Laurent expansions in . We provide expansions of the form factors to order , as required for ultraviolet renormalisation and infrared factorisation of the three-loop form factors.