Limit on tau decay to seven charged particles.

Abstract

A data sample corresponding to a luminosity of 300 pb−1 from e+e− collisions at 29 GeV, obtained using the High Resolution Spectrometer at the SLAC e+e− storage ring PEP, was used to search for τ decay to seven charged particles. No candidates were found and the corresponding upper limit for the branching ratio is B(τ→7π±+ντ+nγ)〈1.9×10−4〉 at 90% confidence level (n≥0). This data sample was also used to obtain the branching ratios of B(τ→5π±+ντ)=(5.1±2.0)×10−4 and B(τ→5π±+π0ντ)=(5.1 ±2.2)×10−4. .AEReceived 23 December 1986DOI:https://doi.org/10.1103/PhysRevD.35.2269©1987 American Physical Society