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

Abstract

We discuss the reduction of errors in the calculation of the form factor $f_{+}^{K\pi }(0)$ 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 $|V_{us}|$.

arXiv comment7 pages, 2 figures, to appear in the Proceedings of Lattice 2016, The 34th International Symposium on Lattice Field Theory, held 24-30 July 2016, at the University of Southampton, UK. v2: references corrected

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Cited by in corpus (1)

• Twisted finite-volume corrections to $K_{l3}$ decays with partially-quenched and rooted-staggered quarks