Weak Matrix Elements of Beyond the Standard Model $\Delta s=2$   four-quark operators from nf=2+1 Domain-Wall fermions
  We report on our computation of the hadronic matrix elements of the four-quark operators needed for the study of $K^0-{\bar K^0}$ mixing beyond the Standard Model (SM). We consider nf=2+1 Domain-Wall fermions on Iwasaki gauge action with lightest unitary pion of 290 MeV and a single lattice spacing a=0.086 fm. The renormalization is performed non-perturbatively through the RI-MOM scheme and our results are converted perturbatively to MSbar. We have estimated the various systematic errors. Our results confirm a previous quenched study, where large ratios of non-SM to SM matrix elements were obtained. 
Nicolas Garron, Peter A Boyle, Renwick J Hudspith and Andrew T Lytle
hep-lat