Kaon B parameter from quenched lattice QCD

We present results of a large-scale simulation for the kaon B parameter B-K in quenched lattice QCD with the Kogut-Susskind quark action. Calculating B-K at 1% statistical accuracy for seven values of lattice spacing in the range a approximate to 0.24-0.04 fm on lattices up to 56(3) x 96, we verify the theoretically predicted quadratic a dependence. Strong indications are found that, with our level of accuracy, alpha(<(MS)over bar>)(1/a)(2) terms arising from our one-loop matching procedure have to be included in the continuum extrapolation. We present B-K(NDR, 2 GeV) = 0.628(42) as our final value, where NDR indicates naive dimensional regularization.