Non-perturbative running and renormalization of kaon four-quark operators with nf=2+1 domain-wall fermions

Abstract

We compute the renormalization factors of four-quark operators needed for the study of $K\toππ$ decay in the $ΔI=3/2$ channel. We evaluate the Z-factors at a low energy scale ($μ_0=1.145 \GeV$) using four different non-exceptional RI-SMOM schemes on a large, coarse lattice ($a\sim 0.14\fm$) on which the bare matrix elements are also computed. Then we compute the universal, non-perturbative, scale evolution matrix of these renormalization factors between $μ_0$ and $3\GeV$. We give the numerical results for the different steps of the computation in two different non-exceptional lattice schemes, and the connection to $\msbar$ at $3\GeV$ is made using one-loop perturbation theory.

11 pages, XXIX International Symposium on Lattice Field Theory, July 10 -16 2011, Squaw Valley, Lake Tahoe, California