Extraction of m_s and |V_us| from Hadronic Tau Decays

Abstract

We review recent work to determine the strange quark mass m_s as well as the proposal to determine |V_{us}| using hadronic tau decay data. The recent update of the strange spectral function by OPAL and their moments of the invariant mass distribution are employed. Our results are |V_us|=0.2208 +- 0.0034 and m_s (2 GeV)=81 +- 22 MeV. Our result is already competitive to the standard extraction of |V_us| from K_e3 decays and to the new proposals to determine it. The error on V_us is dominated by experiment and will be eventually much improved by the B-factories hadronic tau data. Ultimately, a simultaneous fit of both m_s and |V_us| to a set of moments of the hadronic tau decays invariant mass distribution will provide one of the most accurate determinations of these Standard Model parameters.

Invited talk given by J.P. at TAU04, 14-17 September 2004, Nara (Japan)

Cited by in corpus (11)

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• Semileptonic tau decays beyond the Standard Model
• Violation of Quark-Hadron Duality and Spectral Chiral Moments in QCD
• Contour-improved versus fixed-order perturbation theory in hadronic tau decays
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• From hadronic tau decays to the chiral couplings L_10 and C_87