Study of high-multiplicity three-prong and five-prong<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>τ</mml:mi></mml:math>decays at<i>BABAR</i>

Abstract

We present measurements of the branching fractions of three-prong and five-prong $\ensuremath{\tau}$ decay modes using a sample of 430 million $\ensuremath{\tau}$ lepton pairs, corresponding to an integrated luminosity of $468\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$, collected with the BABAR detector at the PEP-II asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ storage rings at SLAC National Accelerator Laboratory. The ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}(3\ensuremath{\pi}{)}^{\ensuremath{-}}\ensuremath{\eta}{\ensuremath{\nu}}_{\ensuremath{\tau}}$, ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}(3\ensuremath{\pi}{)}^{\ensuremath{-}}\ensuremath{\omega}{\ensuremath{\nu}}_{\ensuremath{\tau}}$, and ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{f}_{1}(1285){\ensuremath{\nu}}_{\ensuremath{\tau}}$ branching fractions are presented, as well as a new limit on the branching fraction of the second-class current decay ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{\ensuremath{-}}{\ensuremath{\eta}}^{\ensuremath{'}}(958){\ensuremath{\nu}}_{\ensuremath{\tau}}$. We search for the decay mode ${\ensuremath{\tau}}^{\ensuremath{-}}\ensuremath{\rightarrow}{K}^{\ensuremath{-}}{\ensuremath{\eta}}^{\ensuremath{'}}(958){\ensuremath{\nu}}_{\ensuremath{\tau}}$ and for five-prong decay modes with kaons, and place the first upper limits on their branching fractions.