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The size of chi = arg (-Vts Vtb* Vcs* Vcb) and physics beyond the Standard Model

J. A. Aguilar-Saavedra·F. J. Botella·G. C. Branco·M. Nebot
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Abstract

We analyse the allowed range of values of chi, both in the Standard Model and in models with New Physics, pointing out that a relatively large value of chi, e.g. of order lambda, is only possible in models where the unitarity of the 3x3 Cabibbo-Kobayashi-Maskawa matrix is violated through the introduction of extra Q=2/3 quarks. We study the interesting case where the extra quark is an isosinglet, determining the allowed range for chi and the effect of a large chi on various low-energy observables, such as CP asymmetries in B meson decays. We also discuss the correlated effects which would be observable at high energy colliders, like decays t -> cZ, modifications of the cross section and forward-backward asymmetry in e+ e- -> ttbar and the direct production of a new quark.

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J. A. Aguilar-Saavedra, F. J. Botella, G. C. Branco, M. Nebot. 2004-11-11. The size of chi = arg (-Vts Vtb* Vcs* Vcb) and physics beyond the Standard Model. https://doi.org/10.1016/j.nuclphysb.2004.11.024

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