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arXiv · 1211.1684

Complex-mass scheme and perturbative unitarity

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

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T. Bauer, J. Gegelia, G. Japaridze, S. Scherer. 2012-11-07. Complex-mass scheme and perturbative unitarity. https://doi.org/10.1142/s0217751x12501783

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