The complex-mass scheme for perturbative calculations with unstable particles

Abstract

Perturbative calculations with unstable particles require the inclusion of their finite decay widths. A convenient, universal scheme for this purpose is the complex-mass scheme. It fully respects gauge-invariance, is straight-forward to apply, and has been successfully used for the calculation of various tree-level processes and of the electroweak radiative corrections to e+ e- -> 4f and H -> 4f.

Comments: 5 pages, LaTeX, to appear in the proceedings of the "8th DESY Workshop on Elementary Particle Theory, Loops and Legs in Quantum Field Theory", Eisenach, 2006