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arXiv · hep-lat/0508011

The Kaon B-parameter from Quenched Domain-Wall QCD

Y. Aoki·T. Blum·N. H. Christ·C. Dawson·T. Izubuchi·R. D. Mawhinney·J. Noaki·S. Ohta·K. Orginos·A. Soni·N. Yamada
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Abstract

We present numerical results for the kaon B-parameter, B_K, determined in the quenched approximation of lattice QCD. Our simulations are performed using domain-wall fermions and the renormalization group improved, DBW2 gauge action which combine to give quarks with good chiral symmetry at finite lattice spacing. Operators are renormalized non-perturbatively using the RI/MOM scheme. We study scaling by performing the simulation on two different lattices with a^{-1} = 1.982(30) and 2.914(54) GeV. We combine this quenched scaling study with an earlier calculation of B_K using two flavors of dynamical, domain-wall quarks at a single lattice spacing to obtain B_K(MS,NDR,mu=2GeV)=0.563(21)(39)(30), were the first error is statistical, the second systematic (without quenching errors) and the third estimates the error due to quenching.

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Y. Aoki, T. Blum, N. H. Christ, C. Dawson, T. Izubuchi, R. D. Mawhinney, J. Noaki, S. Ohta, K. Orginos, A. Soni, N. Yamada. 2006-05-15. The Kaon B-parameter from Quenched Domain-Wall QCD. https://doi.org/10.1103/physrevd.73.094507

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