Mass Insertion Formula for Chargino Contribution to \Delta B = 1 Wilson   Coefficients and its Application to CP Asymmetries of B \to K\pi
  The comprehensive mass insertion formula of the b \to s \bar q q transitions was provided for the chargino contributions. The method clarifies physics behind the calculations of the supersymmetric contributions to FCNCs. The result was applied to the analysis of the difference of the CP asymmetries of the B \to K\pi decays. It is shown that the supersymmetry is not responsible for the discrepancy. 
Motoi Endo and Takahiro Yoshinaga
hep-ph