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Tree-level FCNC in the B system: from CP asymmetries to rare decays

G. Barenboim·F. J. Botella·O. Vives
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Abstract

Tree-level Flavor-Changing Neutral Currents (FCNC) are characteristic of models with extra vector-like quarks. These new couplings can strongly modify the B^0 CP asymmetries without conflicting with low--energy constraints. In the light of a low CP asymmetry in B --> J/ψK_{S}, we discuss the implications of these contributions. We find that even these low values can be easily accommodated in these models. Furthermore, we show that the new data from B factories tend to favor an O(20) enhancement of the b --> d l \bar{l} transition over the SM expectation.

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G. Barenboim, F. J. Botella, O. Vives. 2001-04-25. Tree-level FCNC in the B system: from CP asymmetries to rare decays. https://doi.org/10.1103/physrevd.64.015007

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