A measurement of the branching fraction of the decays of the tau- lepton to 2pi- pi+ eta nu

Abstract

We investigate the decay mode τ − → π − π + π − ηντ , where the η subsequently decays to π + π − π 0 using 232 fb−1 data acquired by the BABAR detector. The branching fraction of τ − → π − π + π − ηντ is found to be (1.88 ± 0.14 ± 0.11) × 10−4 . The first error on the is measurement is purely statistical and the second error is estimated systematic error. This measurement is consistent with the prior experimental mesaurements at CLEO and BABAR.