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arXiv · 0711.0935

CP violation and the H-A lineshape

J. Bernabeu·D. Binosi·J. Papavassiliou
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Abstract

In two-Higgs doublet models (and particularly in the MSSM) the CP-even (H) and CP-odd (A) neutral scalars are nearly degenerate in mass, and their s-channel production would lead to nearly overlapping resonances. CP-violating effects may connect these two Higgs bosons, giving origin to one-loop particle mixing, which, due to their mass proximity, can be resonantly enhanced, altering their lineshape significantly. We show that, in general, the effect of such a CP-violating mixing cannot be mimicked by (or be re-absorbed into) a simple redefinition of the H and A masses in the context of a CP-conserving model. Specifically, the effects of the CP-mixing are such that, either the mass-splitting of the H and A bosons lies outside the range allowed by the theory in the absence of CP-mixing, and/or the detailed energy dependence of the produced lineshape is clearly different from the one obtained by redefining the masses, but not allowing any mixing.

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J. Bernabeu, D. Binosi, J. Papavassiliou. 2007-11-06. CP violation and the H-A lineshape. https://doi.org/10.1088/1742-6596/110/7/072031

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