Production of<i>η</i>and<i>ω</i>mesons in<i>τ</i>decay and a search for second-class currents

Abstract

The production of \ensuremath{\eta} and \ensuremath{\omega} mesons in \ensuremath{\tau} decay has been studied with the CLEO detector. A sample of 42 000 ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\ensuremath{\tau}}^{+}$${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$ events at a mean \ensuremath{\surd}s of 10.5 GeV is used in the analysis. The branching ratio B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}\ensuremath{\omega}${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$) is measured to be (1.60\ifmmode\pm\else\textpm\fi{}0.27\ifmmode\pm\else\textpm\fi{}0.41)%. No signal for \ensuremath{\eta} production from \ensuremath{\tau} decay is observed, resulting in 95%-confidence-level upper limits of 1.8% for B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}\ensuremath{\eta}${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$), 2.1% for B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}\ensuremath{\eta}${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\pi}}^{0}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$), and 2.1% for inclusive \ensuremath{\eta} production in \ensuremath{\tau} decay. No evidence is found for decays proceeding via second-class currents.