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

Understand

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.