Small angle expansion of the four-loop cusp anomalous dimension in QCD
Robin Brüser
University of Mainz
Mardi 06/11/2018, 16:00-17:00
Salle Claude Itzykson, Bât. 774, Orme des Merisiers

The cusp anomalous dimension is an important quantity in QCD, appearing in many physical applications. It governs the IR behavior of scattering
amplitudes and is an universal ingredient in heavy quark effective theory (HQET) and soft collinear effective theory. In this talk we consider the angle dependent (HQET) cusp anomalous dimension in QCD and compute its small angle expansion at four loops. We test and partially confirm a conjecture based on the observations made at three loops. That is, the angle dependent cusp anomalous dimension expanded in terms of the light-like cusp anomalous dimension as coupling constant appears to be universal in QCD, pure Yang-Mills and supersymmetric theories.

Contact : Filippo VERNIZZI


Retour en haut