Measurement of the Topological Branching Fractions of theτLepton

Abstract

We report new and precise measurements of the decay branching fractions of the $\tau$ lepton to one and three charged particles. The data, corresponding to an integrated luminosity of 176 ${\mathrm{pb}}^{-1\mathrm{}}$, were collected by the high resolution spectrometer HRS at the $e^{+}{e}^{-}$ storage ring PEP at SLAC operated at $\sqrt{s}=29\mathrm{}$ GeV. The fractions of $\tau$ decays into one and three charged particles are 0.869±0.002±0.003 and 0.130±0.002±0.003, respectively.