Resolving the Higgs-Gluon Coupling with Jets

TL;DR

This work addresses whether the Higgs-gluon coupling arises solely from top-quark loops by probing the logarithmic top-mass structure in Higgs production with two jets. It derives the leading logarithmic behavior for the two-jet final state, showing that the high-p_T regime reveals top-mass dependent effects and introducing a momentum dependent coupling framework with kappa_t and kappa_g to separate top Yukawa and dimension-6 contributions. The authors demonstrate that including a second jet moves many events into top-mass sensitive regions and enhances background rejection, with observable sensitivity in both production rates and kinematic distributions. By analyzing H→WW and H→ττ decays in the Hj and Hjj channels and performing CLs assessments, they show that a combined Hj plus Hjj strategy markedly improves constraints on deviations in the loop-induced Higgs-gluon coupling, highlighting the practical value of two-jet analyses for exploring possible new physics in the top sector.

Abstract

In the Standard Model the Higgs coupling to gluons is almost entirely induced by top quark loops. We derive the logarithmic structure of Higgs production in association with two jets. Just like in the one-jet case the transverse momentum distributions exhibit logarithms of the top quark mass and can be used to test the nature of the loop-induced Higgs coupling to gluons. Using Higgs decays to W bosons and to tau leptons we show how the corresponding analyses hugely benefit from the second jet in the relevant signal rate as well as in the background rejection.

Figures (9)

• Figure 1: Sample Feynman diagrams for the processes $qq\rightarrow Hgg$ and $gq\rightarrow Hgq$, indicating the cuts which contribute to absorptive parts.
• Figure 2: Differential distributions for $m_{Hjj}$ (left) and for $m_{Hj}$ (right) for the $Hjj$ process. The Standard Model curves (SM) include the full top mass dependence while the low energy effective field theory approximation (HEFT) relies on the approximation in Eq.\ref{['eq:higgs_eff2']}. The index 'qq' ('gq') indicates Feynman diagrams with an incoming quark pair (gluon-quark). We assume $\sqrt{S} = 13$ TeV.
• Figure 3: Left to right: correlation plots for the leading $p_{T,j}$ vs $Q_1$ and $p_{T,H}$ vs $Q_1$ for $H jj$ production in the Standard Model, $\kappa_{t,g}=(1,0)$. We also show the ratio SM/BSM, where BSM is defined as $\kappa_{t,g}=(0.8,0.2)$.
• Figure 4: Parton--level $p_{T,H}$ (left) and $p_{T,j_1}$ (right) distributions for $Hj$ and $Hjj$ production. The red curve corresponds to the Standard Model $\kappa_{t,g}=(1,0)$, while the blue curves follow from the BSM hypothesis $\kappa_{t,g}=(0.8,0.2)$. We assume $\sqrt{S}=13$ TeV.
• Figure 5: Parton--level $m_{jj}$ (left), $p_{z,j_1}$ (center) and $p_{z,H}$ (right) distributions for $Hjj$ production.