CP violation in B_d \to \phi K_S in SUSY GUT with right-handed neutrinos

Abstract

CP violation in the B_d system is discussed in the supersymmetric grand unified theory (GUT) with the right-handed neutrinos. Above the GUT scale, the right-handed down-type squarks couple to the right-handed neutrinos. Due to the renormalization group effect, flavor violations in the lepton sector may be transfered to the right-handed down-type squark mass matrix, which affects the CP violation in the B decay. Taking into account this effect, we compare the CP violation in B_d \to \psi K_S and B_d \to \phi K_S processes. We will find that a significant difference is possible between the CP violating phases in two decay processes.