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V_us and m_s from hadronic tau decays

E. Gamiz·M. Jamin·A. Pich·J. Prades·F. Schwab
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Abstract

Recent experimental results on hadronic tau decays into strange particles by the OPAL collaboration are employed to determine V_us and m_s from moments of the invariant mass distribution. Our results are V_us = 0.2208+-0.0034 and m_s(2 GeV) = 81+-22 MeV. The error on V_us is dominated by experiment, and should be improvable in the future. Nevertheless, already now our result is competitive to the standard extraction of V_us from K_e3 decays, and it is compatible with unitarity.

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E. Gamiz, M. Jamin, A. Pich, J. Prades, F. Schwab. 2004-08-03. V_us and m_s from hadronic tau decays. https://doi.org/10.1103/physrevlett.94.011803

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