Infrared structure of $e^{+}{e}^{-}\to 3$ jets at NNLO - the $C_F^2$ contribution

Abstract

We discuss the infrared structure of e+e- -> 2 and 3 jets at NNLO in QCD perturbation theory and describe subtraction terms that render the separate parton-level contributions finite. As a first result, we find that the NNLO C_F^2 contribution to the first moment of the Thrust distribution <1-T> = -20.4 +/- 4.

Comments: 5 pages, Talk given at the 7th DESY Workshop on Elementary Particle Theory: Loops and Legs in Quantum Field Theory, Zinnowitz, Germany April 2004