Non-perturbative mixing and renormalisation of ΔF=2 Four-Fermion Operators

Abstract

We present preliminary results for the Renormalization Group (RG) running of the complete basis of Δ = 2 four-fermion operators in QCD with = 3 dynamical massless flavors. We use O(a)-improved Wilson fermions in a mixed action setup, with chirally rotated Schrödinger functional ( SF) boundary conditions for the valence quarks and Schrödinger functional (SF) boundary conditions for the sea quarks. The RG evolution operators are evaluated non-perturbatively via the matrix step-scaling functions (matrix SSF) while the perturbative running is computed using a new approach [1, 2] relying on the Poincaré-Dulac theorem.