Abstract
In the presence of CP violation, the Higgs-top coupling may have both scalar and pseudoscalar components, κ t and \( {{\widetilde{\kappa}}_t} \), which are bounded indirectly but only weakly by the present experimental constraints on the Higgs-gluon-gluon and Higgs-γ-γ couplings, whereas upper limits on electric dipole moments provide strong additional indirect constraints on \( {{\widetilde{\kappa}}_t} \), if the Higgs-electron coupling is similar to that in the Standard Model and there are no cancellations with other contributions. We discuss methods to measure directly the scalar and pseudoscalar Higgs-top couplings by measurements of Higgs production in association with \( \overline{t}t \), single t and single \( \overline{t} \) at the LHC. Measurements of the total cross sections are very sensitive to variations in the Higgs-top couplings that are consistent with the present indirect constraints, as are invariant mass distributions in \( \overline{t}tH \), tH and \( \overline{t}H \) final states. We also investigate the additional information on κ t and \( {{\widetilde{\kappa}}_t} \) that could be obtained from measurements of the longitudinal and transverse t polarization in the different associated production channels, and the \( \overline{t}t \) spin correlation in \( \overline{t}tH \) events.
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Ellis, J., Hwang, D.S., Sakurai, K. et al. Disentangling Higgs-top couplings in associated production. J. High Energ. Phys. 2014, 4 (2014). https://doi.org/10.1007/JHEP04(2014)004
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DOI: https://doi.org/10.1007/JHEP04(2014)004