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arXiv · 0901.4704

Patterns of Flavour Violation in a Warped Extra Dimensional Model with Custodial Protection

Abstract

We present a particular warped extra dimensional model, where the flavour diagonal and flavour non-diagonal Z boson couplings to left-handed down quarks are protected by the custodial symmetry P_LR. After a brief introduction of the model and of its main theoretical motivations, we present a complete study of rare K and B meson decays, including K+ --> pi+ nu anti-nu, K_L --> pi0 nu anti-nu, B_{s,d} --> mu+ mu- and B_{s,d} --> X_{s,d} nu anti-nu. In particular we restrict the parameter space of the model to the subspace which fits all quark masses, CKM mixing parameters and all the measured Delta F=2 observables, keeping the Kaluza-Klein scale in the reach of LHC (~(2-3)TeV). There we show that, in addition to the one loop contribution of the Standard Model (SM), the dominating new physics contribution to the rare decays of K and B_{s,d} mesons is the tree level exchange of the Z boson of the SM governed by right-handed couplings to down-type quarks. In order to reduce the parameter dependence, we study correlations between various branching ratios of B and K mesons and between Delta F=1 and Delta F=2 observables. The patterns that we find allow to distinguish this new physics scenario from the SM and can offer an opportunity to future experiments to confirm or rule out the model.

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BibTeXRIS

Stefania Gori. 2009-01-29. Patterns of Flavour Violation in a Warped Extra Dimensional Model with Custodial Protection. https://doi.org/10.1088/1742-6596/171/1/012062

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