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arXiv · 1610.00009

Analyzing the CP Nature of a New Scalar Particle via S->Zh Decay

Martin Bauer·Matthias Neubert·Andrea Thamm
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Abstract

Scalar particles $S$ which are singlets under the Standard Model gauge group are generic features of many models of fundamental physics, in particular as possible mediators to a hidden sector. We show that the decay $S\to Zh$ provides a powerful probe of the CP nature of the scalar, because it is allowed only if $S$ has CP-odd interactions. We perform a model-independent analysis of this decay using an effective Lagrangian and compute the relevant Wilson coefficients arising from integrating out heavy fermions to one-loop order.

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Martin Bauer, Matthias Neubert, Andrea Thamm. 2016-09-30. Analyzing the CP Nature of a New Scalar Particle via S->Zh Decay. https://doi.org/10.1103/physrevlett.117.181801

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