Weak corrections to Higgs hadroproduction in association with a top-quark pair
S. Frixione, V. Hirschi, D. Pagani, H. -S. Shao, M. Zaro
TL;DR
This paper addresses the need for precise ttH predictions by computing the weak (EW) corrections at order $\alpha_S^2 \alpha^2$ to $pp\to t\bar t H$, utilizing an automated mixed-coupling expansion in MadGraph5_aMC@NLO and excluding QED effects. It justifies separating weak from QED corrections due to potential Sudakov enhancements and their distinct dependence on Higgs couplings to W/Z and the Higgs self-coupling. The authors present the explicit Born and NLO perturbative structures in $\alpha_S$ and $\alpha$, discuss initial-state dependencies and CKM assumptions, and demonstrate the framework with phenomenological examples at 8, 13, and 100 TeV. Overall, the work improves the accuracy of ttH cross sections and demonstrates the feasibility of automated mixed-coupling calculations for Higgs-top associated production.
Abstract
We present the calculation of the next-to-leading contribution of order $α_S^2α^2$ to the production of a Standard Model Higgs boson in association with a top-quark pair at hadron colliders. All effects of weak and QCD origin are included, whereas those of QED origin are ignored. We work in the MadGraph5_aMC@NLO framework, and discuss sample phenomenological applications at a 8, 13, and 100 TeV $pp$ collider, including the effects of the dominant next-to-leading QCD corrections of order $α_S^3α$.