Complete next-to-leading order QCD corrections to charged Higgs boson associated production with top quark at the CERN Large Hadron Collider

TL;DR

This work delivers the complete NLO QCD corrections to charged Higgs boson production with a top quark via bg -> tH− at the LHC within the MSSM and 2HDM, using the MSbar scheme. It combines LO, virtual, and real contributions with a two-cutoff phase-space slicing method to manage infrared singularities and demonstrates a reduced theoretical uncertainty and a sizable K-factor (~1.6–1.8) across charged Higgs masses from 200 to 1000 GeV. The analysis includes a careful comparison of OS and MSbar mass renormalization schemes and shows that, when running masses are treated consistently, the K-factor becomes nearly independent of tanβ in MSbar. The results provide precise, scheme-aware predictions and decompositions of the NLO corrections, informing LHC searches for charged Higgs scenarios in extended Higgs sectors.

Abstract

The complete next-to-leading order (NLO) QCD corrections to charged Higgs boson associated production with top quark through $b g \to tH^{-}$ at the CERN Large Hadron Collider are calculated in the minimal supersymmetric standard model (MSSM) and two-Higgs-doublet model in the $\bar{MS}$ scheme. The NLO QCD corrections can reduce the scale dependence of the leading order (LO) cross section. The K-factor (defined as the ratio of the NLO cross section to the LO one) does not depend on $\tanβ$ if the same quark running masses are used in the NLO and LO cross sections, and varies roughly from $\sim 1.6$ to $\sim 1.8$ when charged Higgs boson mass increases from 200 GeV to 1000 GeV.

Figures (7)

• Figure 1: Feynman diagrams at LO for $bg\rightarrow t H^-$.
• Figure 2: Feynman diagrams of the virtual correction for the process $bg\rightarrow t H^-$.
• Figure 3: Feynman diagrams of gluon-radiation process of $bg\rightarrow t H^- g$.
• Figure 4: The cross sections [in $fb$] from hard non-collinear regions (dashed), other than hard non-collinear regions (dotted) and total (solid) as a function of $\delta_s$ with $\delta_c=\delta_s/50$, where $\tan\beta=2$, $m_{H^\pm}=200$ GeV and renormalization and factorization scales $\mu=m_{H^\pm}+m_t$.
• Figure 5: (a): the total cross sections as a function of $\mu/\mu_0$ with $\mu_0=m_{H^\pm}+m_t$, where $\tan\beta=2$ and $m_{H^\pm}=200$ GeV. Curves (1)-(4) represent the cross section at NLO in OS scheme (1), NLO in $\overline{MS}$ scheme (2), LO in OS scheme (3), LO in $\overline{MS}$ scheme (4). (b): $\delta$ (defined in text) as a function of $\mu/\mu_0$.