Tt¯H Interactions and T-odd Correlations at Hadron Colliders

Abstract

Abstract We explore C P -violation effects of Higgs-top interactions in the associated production of a Higgs boson with top-pair in the dileptonic decay modes of top-quark originating from proton proton collisions pp → t t ¯ H → ( l + ν l b ) ( l − ν l ¯ b ¯ ) H at NLO in QCD matched to parton shower via T-odd observables using momenta of various particles involved in the process. In particular, we predict the constraints on the C P -violating t t ¯ H coupling obtained through the production asymmetries associated with the T-odd observables in the dileptonic decay channel of the t t ¯ pair for the Large hadron collider (LHC) with centre-of-mass energy of 13 TeV and an integrated luminosity of 139 fb−1. We also present the corresponding limits for future hadron colliders, namely the High Luminosity LHC (HL-LHC) and the Future Circular Collider (FCC-hh). Our estimates of the t t ¯ H interaction strength reveal that the upper bound on pseudoscalar coupling c p corresponding to the largest asymmetry would be of about 1.57 × 10−2 at 2σ C.L. for c s = 1 at the LHC with S =13 TeV for an integrated luminosity of 139 fb−1. The respective limits for HL-LHC and FCC-hh with the projected Luminosities of 3 ab−1 and 30 ab−1 are found to be to 2.7 × 10−3 and 1.3 × 10−4 respectively at 2σ C.L.