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arXiv · 2103.16635

Fitting the $Z b \bar b$ vertex in the two-Higgs-doublet model and in the three-Higgs-doublet model

Darius Jurčiukonis·Luis Lavoura
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Abstract

We investigate the new contributions to the parameters $g_L$ and $g_R$ of the $Z b \bar b$ vertex in a multi-Higgs-doublet model (MHDM). We emphasize that those contributions generally worsen the fit of those parameters to the experimental data. We propose a solution to this problem, wherein $g_R$ has the opposite sign from the one predicted by the Standard Model; this solution, though, necessitates light scalars and large Yukawa couplings in the MHDM.

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Darius Jurčiukonis, Luis Lavoura. 2021-03-30. Fitting the $Z b \bar b$ vertex in the two-Higgs-doublet model and in the three-Higgs-doublet model. https://doi.org/10.1007/jhep07(2021)195

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