Complex-mass scheme and perturbative unitarity
arXiv:1211.1684 · doi:10.1142/S0217751X12501783
Abstract
We derive cutting rules for loop integrals containing propagators with complex masses. Using a field-theoretical model of a heavy vector boson interacting with a light fermion, we demonstrate that the complex-mass scheme respects unitarity order by order in a perturbative expansion provided that the renormalized coupling constant remains real.
Accepted for publication in International Journal of Modern Physics A