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arXiv · 1903.05116

The Z Penguin in Generic Extensions of the Standard Model

Joachim Brod·Martin Gorbahn
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Abstract

Precision flavour observables play an important role in the interpretation of results at the LHC in terms of models of new physics. We present the result for the one-loop Z penguin in generic extensions of the standard model which exhibit exact perturbative unitarity. We use Slavnov-Taylor identities to study the implications of unitarity on the renormalisation of the Z penguin, and derive a manifestly finite result that depends on a reduced set of physical couplings.

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Joachim Brod, Martin Gorbahn. 2019-03-12. The Z Penguin in Generic Extensions of the Standard Model. https://doi.org/10.1007/jhep09(2019)027

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