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arXiv · 1105.3595

On the branching ratio of the "second class" tau --> eta' pi nu_tau decay

N. Paver·Riazuddin
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Abstract

We present an assessment of the standard model expectations for the branching ratio of the isotopic spin and G-parity violating decay tau --> eta' pi nu_tau. The estimate is based on a vector and scalar meson dominance parametrization of the relevant form factors, that explicitly accounts for pi^0-eta-eta' mixing. The numerical results obtained in this framework indicate a branching ratio one order of magnitude (or more) below the current experimental limit, and suggest the possibility of evidencing some novel interaction in high statistics studies of this decay.

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N. Paver, Riazuddin. 2011-05-18. On the branching ratio of the "second class" tau --> eta' pi nu_tau decay. https://doi.org/10.1103/physrevd.84.017302

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