Gluon-fusion contributions to Phi + 2 Jet production

TL;DR

This work computes gluon-fusion contributions to pseudoscalar Higgs production in association with two jets, including full heavy-quark mass effects and interference between top and bottom loops. By extending the CP-even framework to the CP-odd case, it delivers complete amplitudes for the subprocesses qq -> qqA, qg -> qgA, and gg -> ggA involving triangle, box, and pentagon loops, and implements them in the VBFNLO Monte Carlo program. The paper provides extensive numerical results for LHC phenomenology, including cross sections, differential distributions, and CP-sensitive jet azimuthal correlations across MSSM/2HDM parameter spaces, and discusses the validity of heavy-quark approximations. The accompanying Appendices formalize the tensor structures for triangles, boxes, and pentagons and confirm the robustness of the calculation through multiple checks and EFT comparisons.

Abstract

In high energy hadronic collisions a scalar or pseudoscalar Higgs boson, Phi=H,A, can be efficiently produced via gluon fusion, which is mediated by heavy quark loops. We here consider double real emission corrections to Phi=A production, which lead to a Higgs plus two-jet final state, at order alpha_s^4. Full quark mass effects are considered in the calculation of scattering amplitudes for the CP-odd Higgs boson A, as induced by quark triangle-, box- and pentagon-diagrams. They complement the analogous results for a CP-even Higgs boson H in Ref.[1]. Interference effects between loops with top and bottom quarks as well as between CP-even and CP-odd couplings of the heavy quarks are fully taken into account.

Figures (11)

• Figure 1: Examples of Feynman graphs contributing to $A+2$ jet production via gluon fusion.
• Figure 2: $A+2$ jet cross section of the individual contributions of the subprocesses quark-quark, quark-gluon and gluon-gluon scattering for $\tan \beta=1$ as a function of the pseudo-scalar Higgs boson mass, $m_A$. Here, the inclusive cuts (IC) of Eq. \ref{['ICuts']} were applied.
• Figure 3: $A+2$ jet cross section as a function of the pseudo-scalar Higgs boson mass, $m_A$ for different values of $\tan \beta$. The inclusive cuts (IC) of Eq. \ref{['ICuts']} are applied
• Figure 4: Comparison of cross sections for the $\mathcal{CP}$-odd and $\mathcal{CP}$-even Higgs for the full loop calculation and within the effective theory. The inclusive cuts (IC) of Eq. \ref{['ICuts']} are applied.
• Figure 5: Normalized transverse-momentum distributions of the softer jet in $Ajj$ production at the LHC, for different $\tan \beta$ and Higgs-mass values. The inclusive selection cuts of Eq. \ref{['ICuts']} are applied.