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Measurement of the Topological Branching Fractions of the tau lepton at LEP

L3 Collaboration
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Abstract

Using data collected with the L3 detector at LEP from 1992 to 1995 on the Z peak, we determine the branching fractions of the tau lepton into one, three and five charged particles to be: B(tau->(1-prong)) = 85.274 +- 0.105 +- 0.073 %, B(tau->(3-prong)) = 14.556 +- 0.105 +- 0.076 %, B(tau->(5-prong)) = 0.170 +- 0.022 +- 0.026 %. The first uncertainties are statistical and the second systematic. The accuracy of these measurements alone is similar to that of the current world average.

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L3 Collaboration. 2001-07-20. Measurement of the Topological Branching Fractions of the tau lepton at LEP. https://doi.org/10.1016/s0370-2693(01)01099-1

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