Toward the Continuum Limit of $B_K$ with the Quenched Kogut-Susskind Quark Action

JLQCD Collaboration; S. Aoki; M. Fukugita; S. Hashimoto; N. Ishizuka; Y. Iwasaki; K. Kanaya; Y. Kuramashi; H. Mino; M. Okawa; A. Ukawa; T. Yoshie

doi:10.1016/s0920-5632(96)00655-x

arXiv · hep-lat/9608134

Toward the Continuum Limit of $B_K$ with the Quenched Kogut-Susskind Quark Action

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

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Abstract

We present new results of our ongoing project toward a precision determination of the kaon $B$ parameter with the Kogut-Susskind quark action in quenched QCD. New results taken at $β$=6.4 and $β=5.7$ suggest that an apparently linear $a$ dependence of $B_K$ previously observed for $β=5.85-6.2$ arises from a change of curvature from convex to concave as the lattice spacing is reduced. Fitting data for $β\geq 5.93$ with an $O(a^2)$ form yields $B_K$(NDR,2 GeV)=0.587(7)(17) in the continuum limit. We also describe a finite-size study of $B_K$ at $β=$ 6.0 and 6.4, and a reanalysis of the theoretical argument for $O(a^2)$ behavior.

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JLQCD Collaboration, S. Aoki, M. Fukugita, S. Hashimoto, N. Ishizuka, Y. Iwasaki, K. Kanaya, Y. Kuramashi, H. Mino, M. Okawa, A. Ukawa, T. Yoshie. 1996-08-25. Toward the Continuum Limit of $B_K$ with the Quenched Kogut-Susskind Quark Action. https://doi.org/10.1016/s0920-5632(96)00655-x

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