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arXiv · 0906.1386

Status of the Hadronic tau Decay Determination of |V_{us}|

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

We update the hadronic tau determination of |V_{us}|, showing that current strange branching fractions produce results 2-3 sigma lower than 3-family unitarity expectations. Issues related to the size of theoretical uncertainties and results from an alternate, mixed tau-electroproduction sum rule determination (which, by construction, produces a much smaller theoretical uncertainty), are also considered.

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K. Maltman, C. E. Wolfe, S. Banerjee, I. M. Nugent, J. M. Roney. 2009-06-07. Status of the Hadronic tau Decay Determination of |V_{us}|. https://doi.org/10.1016/j.nuclphysbps.2009.03.031

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