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Future e^+ e^- Colliders Sensitivity to H b b-bar Coupling and CP Violation

V. Braguta·A. Chalov·A. Likhoded·R. Rosenfeld
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Abstract

We perform a complete simulation of the process e^+ e^- --> b b-bar nu nu-bar, where nu can be an electron, muon or tau neutrino, in the context of a general Higgs coupling to b quarks. We parametrize the H b b-bar coupling as m_b/v (a + i gamma_5 b). Taking into account interference effects between pure Higgs and Standard Model contributions, we find that sensitivities of the order of 2% and 20% can be obtained at a future e^+ e^- collider for deviations of the $a$ and $b$ parameters respectively from their Standard Model values. Combining our analysis with an independent measurement of Gamma_{H --> b b-bar} can provide evidence about the CP nature of the Higgs sector.

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V. Braguta, A. Chalov, A. Likhoded, R. Rosenfeld. 2002-08-29. Future e^+ e^- Colliders Sensitivity to H b b-bar Coupling and CP Violation. https://doi.org/10.1103/physrevlett.90.241801

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