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arXiv · hep-ex/0609023

Improved measurement of $ψ(2S)$ decays into $τ^{+}τ^{-}$

BES Collaboration·M. AblikimJ
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Abstract

Using 14M $ψ(2S)$ events collected at BESII, the branching fraction of $ψ(2S)\to τ^{+}τ^{-}$ is measured to be $Br_{ττ}=(3.10\pm 0.21\pm 0.38)\times 10^{-3}$, where the first error is statistical and the second is systematic.

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BES Collaboration, M. AblikimJ. 2006-09-13. Improved measurement of $ψ(2S)$ decays into $τ^{+}τ^{-}$. https://doi.org/10.1103/physrevd.74.112003

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