QCD evolution at one percent precision

This project aims at elevating the precision of the perturbative input in the QCD calculations of benchmark “hard” processes by one quantum loop to ensure that the theoretical predictions match the accuracy expected from the experimental facilities of the next generation. This includes the computation of the two-loop coefficientfunctions for generic two-photon processes, QCD splitting functions and evolution kernels up to four loops and three loops for the forward and non-forward (generalized) parton distributions, respectively, and four-loop fragmentation functions. In addition, the matching relations to lattice renormalization schemes will be provided with similar precision. The project will make extensive use of dedicated large-scale computer algebra programs for the necessary analytic computations and also of novel techniques based on conformal symmetry, which in many cases allow one to reduce the amount of loops to be computed by one using group theory methods.

DFG Programme Research Units

Subproject of FOR 2926:  Next Generation Perturbative QCD for Hadron Structure: Preparing for the Electron-Ion Collider