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arXiv · 1507.07926

Boosting the Direct CP Measurement of the Higgs-Top Coupling

Matthew R. Buckley·Dorival Goncalves
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Abstract

Characterizing the 125 GeV Higgs is a critical component of the physics program at the LHC Run II. In this Letter, we consider $t\bar{t}H$ associated production in the dileptonic mode. We demonstrate that the difference in azimuthal angle between the leptons from top decays can directly reveal the CP-structure of the top-Higgs coupling with the sensitivity of the measurement substantiality enhanced in the boosted Higgs regime. We first show how to access this channel via $H \to b\bar{b}$ jet-substructure tagging, then demonstrate the ability of the new variable to measure CP. Our analysis includes all signal and background samples simulated via the MC@NLO algorithm including hadronization and underlying-event effects. Using boosted Higgs substructure with dileptonic tops, we find that the top-Higgs coupling strength and the CP structure can be directly probed with achievable luminosity at the 13 TeV LHC.

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Matthew R. Buckley, Dorival Goncalves. 2016-03-03. Boosting the Direct CP Measurement of the Higgs-Top Coupling. https://doi.org/10.1103/physrevlett.116.091801

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