B_K from Two-flavor Dynamical Domain Wall Fermions

Abstract

We report preliminary results from an ongoing calculation of $B_K$ for $N_f=2$ dynamical QCD with domain wall fermions. Simulations have been done with three dynamical quark masses on $16^3\times 32$ volumes with $L_s=12$, where the lattice spacing is $a^{-1}=1.81(6)$ GeV. Using measurements on $\sim 70$ lattices for each dynamical mass and extrapolating $\text{mdyn}=\text{mval}$ to the kaon point, we find $B_K^{\overline{\mathrm{MS}}}(\mu =2\mathrm{GeV})=0.503(20)$.

Comments: Lattice2003(matrix), 3 pages, 2 figures