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arXiv · 0910.3130

Feynman rules for the rational part of the Electroweak 1-loop amplitudes

M. V. Garzelli·I. Malamos·R. Pittau
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Abstract

We present the complete set of Feynman rules producing the rational terms of kind R_2 needed to perform any 1-loop calculation in the Electroweak Standard Model. Our results are given both in the 't Hooft-Veltman and in the Four Dimensional Helicity regularization schemes. We also verified, by using both the 't Hooft-Feynman gauge and the Background Field Method, a huge set of Ward identities -up to 4-points- for the complete rational part of the Electroweak amplitudes. This provides a stringent check of our results and, as a by-product, an explicit test of the gauge invariance of the Four Dimensional Helicity regularization scheme in the complete Standard Model at 1-loop. The formulae presented in this paper provide the last missing piece for completely automatizing, in the framework of the OPP method, the 1-loop calculations in the SU(3) X SU(2) X U(1) Standard Model.

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M. V. Garzelli, I. Malamos, R. Pittau. 2010-10-01. Feynman rules for the rational part of the Electroweak 1-loop amplitudes. https://doi.org/10.1007/jhep01(2010)040%2010.1007%2Fjhep10(2010)097

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