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arXiv · 1611.04118

Kaon semileptonic decays with $N_f=2+1+1$ HISQ fermions and physical light-quark masses

E. Gamiz·A. Bazavov·C. Bernard·C. DeTar·D. Du·A. X. El-Khadra·E. D. Freeland·Steven Gottlieb·U. M. Heller·J. Komijani·A. S. Kronfeld·J. Laiho·P. B. Mackenzie·E. T. Neil·T. Primer·J. N. Simone·R. Sugar·D. Toussaint·R. S. Van de Water·Ran Zhou
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Abstract

We discuss the reduction of errors in the calculation of the form factor $f_+^{K π}(0)$ with HISQ fermions on the $N_f=2+1+1$ MILC configurations from increased statistics on some key ensembles, new data on ensembles with lattice spacings down to 0.042 fm and the study of finite-volume effects within staggered ChPT. We also study the implications for the unitarity of the CKM matrix in the first row and for current tensions with leptonic determinations of $\vert V_{us}\vert$.

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E. Gamiz, A. Bazavov, C. Bernard, C. DeTar, D. Du, A. X. El-Khadra, E. D. Freeland, Steven Gottlieb, U. M. Heller, J. Komijani, A. S. Kronfeld, J. Laiho, P. B. Mackenzie, E. T. Neil, T. Primer, J. N. Simone, R. Sugar, D. Toussaint, R. S. Van de Water, Ran Zhou. 2016-11-20. Kaon semileptonic decays with $N_f=2+1+1$ HISQ fermions and physical light-quark masses. https://arxiv.org/abs/1611.04118

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