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arXiv · hep-ex/9707023

An upper limit on the branching ratio for tau decays into seven charged particles

The OPAL Collaboration·K. Ackerstaff et al
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Abstract

We have searched for decays of the tau lepton into seven or more charged particles, using data collected with the OPAL detector from 1990 to 1995 in e^+e^- collisions at sqrt(s) ~ M_Z. No candidate events were found and an upper limit on the branching ratio for tau decays into seven charged particles of 1.8 x 10^-5 at the 95% confidence level was determined.

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The OPAL Collaboration, K. Ackerstaff et al. 1997-07-10. An upper limit on the branching ratio for tau decays into seven charged particles. https://doi.org/10.1016/s0370-2693(97)00648-5

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