Measuring CP nature of top-Higgs couplings at the future LargeHadron electron Collider

2017-07
Coleppa, B.
Kumar, M.
Kumar, S.
Elsevier
Abstract
We investigate the sensitivity of top-Higgs coupling by considering the associated vertex as CP phase (ζt) dependent through the process pe−→t¯hνe in the future Large Hadron electron Collider. In particular the decay modes are taken to be h→bb¯ and t¯ → leptonic mode. Several distinct ζt dependent features are demonstrated by considering observables like cross sections, top-quark polarisation, rapidity difference between h and t¯ and different angular asymmetries. Luminosity (L) dependent exclusion limits are obtained for ζt by considering significance based on fiducial cross sections at different σ-levels. For electron and proton beam-energies of 60 GeV and 7 TeV respectively, at L=100 fb−1, the regions above π/5<ζt≤π are excluded at 2σ confidence level, which reflects better sensitivity expected at the Large Hadron Collider. With appropriate error fitting methodology we find that the accuracy of SM top-Higgs coupling could be measured to be κ=1.00±0.17(0.08) at s=1.3(1.8) TeV for an ultimate L=1ab−1.
Keywords
Electron-proton collision , Top-Higgs coupling , Top polarisation , PROTON COLLISIONS , ATLAS DETECTOR , LHC , BOSON , DECAYS , MASS , QUARKS , SPIN
Citation
Coleppa, B. et al. 2017. Measuring CP nature of top-Higgs couplings at the future LargeHadron electron Collider. Physics Letters B, 770 (2017), pp. 335-341