Measurement of the topological branching fractions of the τ lepton at LEP

Using data collected with the L3 detector at LEP from 1992 to 1995 on the Z peak, we determine the branching fractions of the τ lepton into one, three and five charged particles to be: B(τ→(1-prong))=85.274±0.105±0.073%,B(τ→(3-prong))=14.556±0.105±0.076%,B(τ→(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.