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arXiv · 1411.1501

Calculation of BSM Kaon B-parameters using Staggered Quarks

Yong-Chull Jang·Hwancheol Jeong·Jangho Kim·Seonghee Kim·Weonjong Lee·Jaehoon Leem·Jeonghwan Pak·Sungwoo Park·Chulwoo Jung·Hyung-Jin Kim·Stephen R. Sharpe·Boram Yoon
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Abstract

We present updated results for kaon B-parameters for operators arising in models of new physics. We use HYP-smeared staggered quarks on the $N_f = 2+1$ MILC asqtad lattices. During the last year we have added new ensembles, which has necessitated chiral-continuum fitting with more elaborate fitting functions. We have also corrected an error in a two-loop anomalous dimension used to evolve results between different scales. Our results for the beyond-the-Standard-Model B-parameters have total errors of $5-10$\%. We find that the discrepancy observed last year between our results and those of the RBC/UKQCD and ETM collaborations for some of the B-parameters has been reduced from $4\!-\!5\,σ$ to $2\!-\!3\,σ$.

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Yong-Chull Jang, Hwancheol Jeong, Jangho Kim, Seonghee Kim, Weonjong Lee, Jaehoon Leem, Jeonghwan Pak, Sungwoo Park, Chulwoo Jung, Hyung-Jin Kim, Stephen R. Sharpe, Boram Yoon. 2014-11-06. Calculation of BSM Kaon B-parameters using Staggered Quarks. https://arxiv.org/abs/1411.1501

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