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arXiv · 0807.3195

Status of the Hadronic Tau Determination of V_us

K. Maltman·C. E. Wolfe·S. Banerjee·I. Nugent·J. M. Roney
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Abstract

We update the extraction of |V_{us}| 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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K. Maltman, C. E. Wolfe, S. Banerjee, I. Nugent, J. M. Roney. 2008-07-21. Status of the Hadronic Tau Determination of V_us. https://doi.org/10.1142/s0217751x08041803

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