1 1/Nc and ε ′ /ε ∗
نویسنده
چکیده
We present a recent analysis of ε′/ε in the 1/Nc expansion. We show that the 1/Nc corrections to the matrix element of Q6 are large and positive, indicating a ∆I = 1/2 enhancement similar to the one of Q1 and Q2 which dominate the CP conserving amplitude. This enhances the CP ratio and can bring the standard model prediction close to the measured value for central values of the parameters. Several comments on the theoretical status of ε′/ε and the errors in its calculation are given.
منابع مشابه
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