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arXiv · hep-ph/9904379

A Real CKM Matrix and Physics Beyond the Standard Model

G. C. Branco·F. Cagarrinho·F. Krüger
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Abstract

We study the possible existence of a real Cabibbo-Kobayashi-Maskawa (CKM) matrix, with CP violation originating from physics beyond the standard model (SM). We show that present experimental data allow for a real CKM matrix provided that new physics also contributes to Delta m_{B_d} by at least 20% of the SM contribution (for rho > 0), besides generating CP violation in the kaon sector. The naturalness of a real CKM matrix is studied within the framework of general multi-Higgs-doublet models with spontaneous CP violation. As an example, we discuss a specific two-Higgs-doublet model and its implications for CP asymmetries in non-leptonic neutral B-meson decays.

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G. C. Branco, F. Cagarrinho, F. Krüger. 1999-04-18. A Real CKM Matrix and Physics Beyond the Standard Model. https://doi.org/10.1016/s0370-2693(99)00644-9

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