Status of the Hadronic Tau Determination of Vus
Abstract
We update the extraction of |Vus| from hadronic tau decay data in light of recent BaBar and Belle results on the branching fractions of a number of important strange decay modes. A range of sum rule analyses is performed, particular attention being paid to those based on "non-spectral weights", developed previously to bring the slow convergence of the relevant integrated D=2 OPE series under improved control. Results from the various sum rules are shown to be in good agreement with one another, but ~3 sigma below expectations based on 3-family unitarity. Important avenues for future study are briefly discussed.
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