K 0 Mixing Beyond the SM from Nf = 2 tmQCD

We present preliminary results on the of neutral kaon oscillations in extensions of the Standard Model. Using Nf = 2 maximally twisted sea quarks and Osterwalder-Seiler valence quarks, we achieve both O(a)-improvement and continuum-like renormalization pattern for the relevant fourfermion operators. We perform simulations at three values of the lattice spacing and extrapolate/interpolate our results to the continuum limit and phy sical light/strange quark mass. The calculation of the renormalization constants of the complete operator basis is performed nonperturbatively in the RI-MOM scheme. The XXVIII International Symposium on Lattice Field Theory ‐LATTICE2010