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arXiv · hep-ex/9908025

Update of the Search for the Neutrinoless Decay $τ\to μγ$

A. Anastassov·CLEO Collaboration
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Abstract

We present an update of the search for the lepton family number violating decay $τ\to μγ$ using a complete CLEO II data sample of 12.6 million $τ^+τ^-$ pairs. No evidence of a signal has been found and the corresponding upper limit is $ \BR(τ\to μγ) < 1.0 \times 10^{-6} $ at 90% CL, significantly smaller than previous limits. All quoted results are preliminary.

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A. Anastassov, CLEO Collaboration. 1999-08-06. Update of the Search for the Neutrinoless Decay $τ\to μγ$. https://doi.org/10.1103/physrevd.61.071101

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