A search for neutrinoless tau decays to three leptons

Abstract

Using approximately 350 million à + à - pair events recorded with the BaBar detector at the Stanford Linear Accelerator Center between 1999 and 2006, a search has been made for neutrinoless, lepton-flavor violating tau decays to three lighter leptons. All six decay modes consistent with conservation of electric charge and energy have been considered. With signal selection efficiencies of 5-12%, we obtain 90% confidence level upper limits on the branching fraction B (à [arrow right] [cursive l][cursive l][cursive l]) in the range (4 - 8) à 10 -8 .