Gluino–squark contributions to CP violations in the kaon system Original Research Article

Recently it was shown, within the mass insertion approximation (MIA), that the gluino mediated flavor changing neutral current (FCNC) interactions can saturate both ϵK and Re(ϵ′/ϵK) even for the real Cabibbo–Kobayashi–Maskawa (CKM) matrix through a single CP violating parameter (δ12d)LL. In this work, we extend our previous analysis to the nonvanishing KM phase, and to the effective SUSY model where the MIA is no longer a good approximation. In our model, ϵK and B0−B0 mixing can receive significant SUSY contributions. Therefore the usual constraints on ρ and η in the Wolfenstein parametrization of the CKM matrix can be relaxed except for the |Vub/Vcb| from the semileptonic b→u transition. This affects K→πνν̄ and KL→μ+μ− indirectly, even if they are not directly induced by gluino-mediated FCNC, while KL→π0e+e− is influenced both directly and indirectly. Differences between our model and other SUSY models enhancing Re(ϵ′/ϵK) are discussed in detail.