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arXiv · 1110.0471

A Solution to the Flavor Problem of Warped Extra-Dimension Models

Martin Bauer·Raoul Malm·Matthias Neubert
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Abstract

A minimal solution to the flavor problem of warped extra-dimension models, i.e. the excessive mixed-chirality contribution to CP violation in K-Kbar mixing arising from Kaluza-Klein (KK) gluon exchange, is proposed. Extending the strong-interaction gauge group in the bulk by an additional SU(3), and breaking this symmetry to QCD via boundary conditions, the constraints arising from the epsilon_K parameter are significantly relaxed. As a result, KK scales M_KK ~ 2 TeV are consistent with all flavor observables without significant fine-tuning. The model predicts the existence of an extended Higgs sector featuring massive color-octet scalars and a tower of KK pseudo-axial gluon resonances, whose existence is not in conflict with recent LHC dijet bounds.

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Martin Bauer, Raoul Malm, Matthias Neubert. 2012-09-21. A Solution to the Flavor Problem of Warped Extra-Dimension Models. https://doi.org/10.1103/physrevlett.108.081603

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