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Precise Determination of |V{us}| from Lattice Calculations of Pseudoscalar Decay Constants

William J. Marciano
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Abstract

Combining the ratio of experimental kaon and pion decay widths, Gamma(K to mu antineutrino{mu} (gamma)) / Gamma(pi to mu \antineutrino (gamma)), with a recent lattice gauge theory calculation of f{K}/f{pi} provides a precise value for the CKM quark mixing matrix element |V{us}|=0.2236(30) or if 3 generation unitarity is assumed |V{us}|=0.2238(30). Comparison with other determinations of that fundamental parameter, implications, and an outlook for future improvements are given.

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William J. Marciano. 2004-02-27. Precise Determination of |V{us}| from Lattice Calculations of Pseudoscalar Decay Constants. https://doi.org/10.1103/physrevlett.93.231803

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