1211.1684 (T. Bauer et al.)

Complex-mass scheme and perturbative unitarity    [PDF]

T. Bauer, J. Gegelia, G. Japaridze, S. Scherer

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.

View original: http://arxiv.org/abs/1211.1684