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arXiv · hep-lat/9710073

Kaon B parameter from quenched Lattice QCD

JLQCD Collaboration·S. Aoki·M. Fukugita·S. Hashimoto·N. Ishizuka·Y. Iwasaki·K. Kanaya·Y. Kuramashi·M. Okawa·A. Ukawa·T. Yoshié
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Abstract

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 $a\approx 0.24-0.04$ fm on lattices up to $56^3\times 96$, we verify a quadratic $a$ dependence of $B_K$ theoretically predicted. Strong indications are found that, with our level of accuracy, $α_{\bar{MS}}(1/a)^2$ 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, as obtained by a fit including the $α_{\bar{MS}}(1/a)^2$ term.

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JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, Y. Kuramashi, M. Okawa, A. Ukawa, T. Yoshié. 1997-10-21. Kaon B parameter from quenched Lattice QCD. https://doi.org/10.1103/physrevlett.80.5271

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