Effects of the right-handed neutrinos on \Delta S = 2 and \Delta B = 2 processes in supersymmetric SU(5) model

Abstract

We discuss an extra source of CP and flavor violations in supersymmetric SU(5) grand unified model with the right-handed neutrinos. In such a model, the right-handed down-type squarks \tilde{d}_R interact with the right-handed neutrinos above the GUT scale, and the renormalization group effect can generate sizable off-diagonal elements in the mass matrix of \tilde{d}_R. Because of new Yukawa phases which exist in the SU(5) model, these off-diagonal elements have, in general, large CP violating phases. The renormalization group induced off-diagonal elements affect the K and B decays. In particular, in this model, supersymmetric contribution to the \epsilon_K parameter can be as large as the currently measured experimental value, and hence the effect might be seen as an anomaly in the on-going test of the Cabibbo-Kobayashi-Maskawa triangle.