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arXiv · 1607.05291

Accurate predictions for charged Higgs production: closing the $m_{H^{\pm}}\sim m_t$ window

Abstract

We present predictions for the total cross section for the production of a charged Higgs boson in the intermediate-mass range ($m_{H^{\pm}}\sim m_t$) at the LHC, focusing on a type-II two-Higgs-doublet model. Results are obtained at next-to-leading order (NLO) accuracy in QCD perturbation theory, by studying the full process $pp\to H^\pm W^\mp b \bar b$ in the complex-(top)-mass scheme with massive bottom quarks. Compared to lowest-order predictions, NLO corrections have a sizeable impact: they increase the cross section by roughly 50\% and reduce uncertainties due to scale variations by more than a factor of two. Our computation reliably interpolates between the low- and high-mass regime. Our results provide the first NLO prediction for charged Higgs production in the intermediate-mass range and therefore allow to have NLO accurate predictions in the full $m_{H^{\pm}}$ range. The extension of our results to different realisations of the two-Higgs-doublet model or to the supersymmetric case is also discussed.

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Celine Degrande, Rikkert Frederix, Valentin Hirschi, Maria Ubiali, Marius Wiesemann, Marco Zaro. 2017-06-21. Accurate predictions for charged Higgs production: closing the $m_{H^{\pm}}\sim m_t$ window. https://doi.org/10.1016/j.physletb.2017.06.037

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