Lattice B-parameters for $\mathrm{\Delta }S=2$ and $\mathrm{\Delta }I=3\mathrm{/}2$ Operators

We compute several matrix elements of dimension-six four-fermion operators and extract their B-parameters. The calculations have been performed with the tree-level Clover action at $\beta =6.0$. The renormalization constants and mixing coefficients of the lattice operators have been obtained non-perturbatively. In the $\text{MSbar}$ renormalization scheme, at a renormalization scale $\mu \simeq 2$ GeV, we find $B_K (B_9^{3/2}) = 0.66(11), B_7^{3/2} = 0.72(5)$and$B_8^{3/2} = 1.03(3)$\mathrm{.}Theresultfor$B_8^{3/2}$ has important implications for the calculation of ${ϵ}^{\mathrm{\prime }}\mathrm{/}ϵ$.