New Physics contribution to $B\to K\pi$ decays in SCET

Abstract

We analyze the $5\sigma$ difference between the CP asymmetries of the $B^0\to K^{+}{\pi }^{-}$ and $B^{+}\to K^{+}{\pi }^0$ decays within the Soft Collinear Effective Theory. We find that in the Standard Model, such a big difference cannot be achieved. We classify then the requirements for the possible New Physics models, which can be responsible for the experimental results. As an example of a New Physics model we study minimal supersymmetric models, and find that the measured asymmetry can be obtained with non-minimal flavor violation.

Comments: 13 pages, one reference added, section V modified, conclusions unchanged