We study the flavor physics from down-type squark mixings in the context of the minimal supersymmetric standard model. We consider, in particular, CP asymmetries in K and B meson decays and related observables thereof, using mass insertion approximation. For large tan β, a single LL mass insertion can considerably modify both direct and indirect CP violations in the kaon sector. We take into account the neutron electric dipole moment and other rare kaon decays as well.
Also, we point out that B → $X_d$r is of great importance in the sdown--sbottom mixing phenomenology, both as a constraint and as a place to look for an experimental signature. The $(S_3)^3$ alignment model has significant potential to modify kaonic CP violations and B → $X_d$r, but not $B^0$--$\overline{B^0}$ mixing. Among the four mass insertions relevant to b → s transitions, $(δ_{23}^d)_{LR}$ and $(δ_{23}^d)_{RL}$ are more likely to drive $S_{φ K}$ close to the current negative central value, than $(δ_{23}^d)_{LL}$ or $(δ_{23}^d)_{RR}$. We show correlations between $S_{φ K}$ and related quantities. Finally, we present an example of $Z_6$--I heterotic orbifold model that is consistent with the measured $\overline{m}_c/\overline{m}_t$, $\overline{m}_s/\overline{m}_b$, and $V_{cb}$.
