Mixing of $K^0$ and $B^0$ neutral mesons within the minimum supersymmetry model

Mixing of $K^0$ and $B^0$ mesons is studied in the scope of the minimum supersymmetry model (MSSM) with a type II Yukawa sector and explicit violation of $CP$ invariance in the Higgs potential. The mixing parameters $\Delta m_{LS}$ and $\varepsilon$ are calculated in the limit of the low-energy four-fermion approximation with a charged Higgs boson exchange. It is shown that supersymmetric effects are very small for $K^0$ mesons and may be quite significant for $B_s^0$ and $B_d^0$ mesons, which imposes constraints on the MSSM parameter space.