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arXiv · 0910.5576

Determination of $B_K$ using improved staggered fermions (I): SU(3) chiral perturbation theory fit

Taegil Bae·Hyung-Jin Kim·Jangho Kim·Jongjeong Kim·Kwangwoo Kim·Boram Yoon·Weonjong Lee·Chulwoo Jung·Stephen R. Sharpe
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Abstract

We present the results for $B_K$ calculated using HYP-smeared staggered fermions using lattices generated by the MILC collaboration using the asqtad staggered action. We have done the calculation on 8 ensembles of these lattices, including three different lattice spacings ($a=0.12, 0.09, 0.06$ fm). We fit the data to forms based on those predicted by SU(3) mixed-action partially-quenched staggered chiral perturbation theory. Our preliminary result is $ B_K(\text{NDR},μ=2\text{GeV}) = 0.528 \pm 0.011 \pm 0.048 $, where the first error is statistical and the second systematic. The error turns out to be larger than that from an analysis using SU(2) chiral perturbation theory.

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Taegil Bae, Hyung-Jin Kim, Jangho Kim, Jongjeong Kim, Kwangwoo Kim, Boram Yoon, Weonjong Lee, Chulwoo Jung, Stephen R. Sharpe. 2009-10-29. Determination of $B_K$ using improved staggered fermions (I): SU(3) chiral perturbation theory fit. https://arxiv.org/abs/0910.5576

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