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Non-degenerate quark mass effect on $B_K$ with a mixed action

Taegil Bae·Jongjeong Kim·Weonjong Lee
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Abstract

We investigate the effect of non-degenerate quarks on $B_K$. This effect is noticeably large for $B_K$ (significantly larger than statistical uncertainty). Hence, it is important to include this effect in order to determine $B_K$ with higher precision. We also observe that the quality of fitting for $B_K$ gets better when we include non-degenerate combinations to fit to the prediction by Van de Water and Sharpe. However, this effect on $B_7^{(3/2)}$ and $B_8^{(3/2)}$ turns out to be relatively small.

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Taegil Bae, Jongjeong Kim, Weonjong Lee. 2005-10-21. Non-degenerate quark mass effect on $B_K$ with a mixed action. https://arxiv.org/abs/hep-lat/0510008

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