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arXiv · 1206.0668

New physics in ε' from chromomagnetic contributions and limits on Left-Right symmetry

Stefano Bertolini·Jan O. Eeg·Alessio Maiezza·Fabrizio Nesti
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Abstract

New physics in the chromomagnetic flavor changing transition s->dg* can avoid the strong GIM suppression of the Standard Model and lead to large contributions to CP-violating observables, in particular to the epsilon' parameter, that we address here. We discuss the case of the Left-Right symmetric models, where this contribution implies bounds on the phases of the right-handed quark mixing matrix, or in generic models with large phases a strong bound on the Left-Right symmetry scale. To the leading order, a numeric formula for epsilon' as a function of the short-distance coefficients for a wide class of models of new physics is given.

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Stefano Bertolini, Jan O. Eeg, Alessio Maiezza, Fabrizio Nesti. 2016-03-31. New physics in ε' from chromomagnetic contributions and limits on Left-Right symmetry. https://doi.org/10.1103/physrevd.86.095013

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