Abstract
In this paper, we put constraints on anomalous \( \mathcal{C}\mathcal{P} \)-violating top-Higgs couplings using the currently available Higgs data and explore the prospect of measuring these couplings at 240 GeV TLEP. We find that the \( \mathcal{C}\mathcal{P} \)-violating phase ξ is currently limited in the range |ξ| <0.6π at 95% C.L. and may be further constrained to |ξ| <0.07π at TLEP. Under this consideration, we further investigate the observability of the scalar (ξ =0), pseudoscalar (ξ =0.5π) and mixed (ξ =0.25π) top-Higgs interactions through the channel \( pp\to t\left(\to {\ell}^{+}{\nu}_{\ell }b\right)h\left(\to b\overline{b}\right)j \). We find that it is most promising to observe pure pseudoscalar interactions with y t = y SM t , although this will be challenging due to a low signal to background ratio. We also find that the anomalous top-Higgs couplings can lead to sizeable differences in lepton forward-backward asymmetries and can be distinguished by measuring the lepton angular distributions from polarised top quarks at 14 TeV LHC.
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Kobakhidze, A., Wu, L. & Yue, J. Anomalous top-Higgs couplings and top polarisation in single top and Higgs associated production at the LHC. J. High Energ. Phys. 2014, 100 (2014). https://doi.org/10.1007/JHEP10(2014)100
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DOI: https://doi.org/10.1007/JHEP10(2014)100