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arXiv · 1101.2685

Finite volume effects in $B_K$ with improved staggered fermions

Jangho Kim·Chulwoo Jung·Hyung-Jin Kim·Weonjong Lee·Stephen R. Sharpe
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Abstract

We extend our recent unquenched ($N_f=2+1$ flavor) calculation of $B_K$ using improved staggered fermions by including in the fits the finite volume shift predicted by one-loop staggered chiral perturbation theory. The net result is to lower the result in the continuum limit by 0.6%. This shift is slightly smaller than our previous estimate of finite volume effects based on a direct comparison between different volumes. To include the finite volume effects in a reasonable time, we found it necessary to calculate them using Graphics Processing Units.

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Jangho Kim, Chulwoo Jung, Hyung-Jin Kim, Weonjong Lee, Stephen R. Sharpe. 2011-03-28. Finite volume effects in $B_K$ with improved staggered fermions. https://doi.org/10.1103/physrevd.83.117501

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