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arXiv · hep-ex/9812017

A Measurement of the tau->electron Branching Ratio

The OPAL Collaboration·G. Abbiendi et al
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Abstract

The branching ratio for the decay tau->e nue nutau has been measured using Z0 decay data collected by the OPAL experiment at LEP. In total 33073 tau->e nue nutau candidates were identified from a sample of 186197 selected tau decays, giving a branching ratio of 17.81 +- 0.09(stat) +_ 0.06(sys)%. This result is combined with other measurements to test e-mu and mu-tau universality in charged-current weak interactions. Additionally, the strong coupling constant alpha_s has been extracted and evolved to the Z0 mass scale, giving alpha_s = 0.1204 +- 0.0011(exp) +- 0.0019(theory).

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The OPAL Collaboration, G. Abbiendi et al. 1998-12-14. A Measurement of the tau->electron Branching Ratio. https://doi.org/10.1016/s0370-2693(98)01553-6

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