
We introduce a new parameterization of fourfermion operator matrix elements which does not involve quark masses and thus allows a reduction of systematic uncertainties. In order to simplify the matching between lattice and continuum renormalization schemes, we express our results in terms of renormalization group invariant Bparameters which are renormalizationscheme and scale independent. As an application of our proposal, matrix elements of Delta I = 3/2 and SUSY Delta S = 2 operators have been computed. The calculations have been performed using the treelevel improved Clover lattice action at two different values of the strong coupling constant (beta = 6/g(2) = 6.0 and 6,2), in the quenched approximation. Renormalization constants and mixing coefficients of lattice operators have been obtained nonperturbatively. Using lowest order chi PT, we also obtain (pi pi\O7\K)(I=2)(NDR) = (0.11 +/ 0.02) GeV4 and (pi pi\O8\K)(I=2)(NDR) = (0.51 +/ 0.05) GeV4 at mu=2 GeV.
