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arXiv · hep-lat/9711012

$K^{+}\toπ^{+}π^{0}$ Decay Amplitude in Quenched Lattice QCD

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

A new study is reported of a lattice QCD calculation of the $K^+\toπ^+ π^0 $ decay amplitude with the Wilson quark action in the quenched approximation at $β=6.1$. The amplitude is extracted from the $K\toππ$ Green function, and a conversion to the continuum value is made employing a recent one-loop calculation of chiral perturbation theory. The result is consistent with the experimental value if extrapolated to the chiral limit.

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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. Yoshie. 1997-11-07. $K^{+}\toπ^{+}π^{0}$ Decay Amplitude in Quenched Lattice QCD. https://doi.org/10.1016/s0920-5632(97)00747-0

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