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arXiv · 1710.05563

CP violation in 2HDM and EFT: the ZZZ vertex

Hermès Bélusca-Maïto·Adam Falkowski·Duarte Fontes·Jorge. C. Romão·João P. Silva
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Abstract

We study the CP violating ZZZ vertex in the two-Higgs doublet model, which is a probe of a Jarlskog-type invariant in the extended Higgs sector. The form factor $f_4^Z$ is evaluated at one loop in a general $R_\xi$ gauge and its magnitude is estimated in the realistic parameter space. Then we turn to the decoupling limit of the two-Higgs doublet model, where the extra scalars are heavy and the physics can be described by the Standard Model supplemented by higher-dimensional operators. The leading operator contributing to $f_4^Z$ at one loop is identified. The CP violating ZZZ vertex is not generated in the effective theory by dimension-8 operators, but instead arises only at the dimension-12 level, which implies an additional suppression by powers of the heavy Higgs mass scale.

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Hermès Bélusca-Maïto, Adam Falkowski, Duarte Fontes, Jorge. C. Romão, João P. Silva. 2017-10-16. CP violation in 2HDM and EFT: the ZZZ vertex. https://doi.org/10.1007/jhep04(2018)002

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