Search for the decay τ^-→4π^-3π⁺(π⁰)ν_τ

Authors

K. W. Edwards, Carleton University
Kenneth A. Bloom, University of Nebraska-LincolnFollow
CLEO Collaboration

Document Type

Article

Date of this Version

11-1-1997

Comments

Published by American Physical Society. Phys. Rev. D 56, 5297 (1997). Permission to use. http://prd.aps.org/. Copyright © 1997 American Physical Society.

Abstract

We have searched for the decay of the τ lepton into seven charged particles and zero or one π⁰. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) and correspond to an integrated luminosity of 4.61 fb^-. No evidence for a signal is found. Assuming all the charged particles are pions, we set an upper limit on the branching fraction B(τ^-→4π^-3π⁺(π⁰) ν_τ) < 2.4X10^-6 at the 90% confidence level. This limit represents a significant improvement over the previous limit.