Measurement of the Inclusive Branching Fractionτ−→ντπ−π0+NeutralMeson(s)

We measure an inclusive branching fraction of (13.9 ± ${2.0}_{-2.2\mathrm{}}^{+1.9\mathrm{}}$)% for the decay ${\tau }^{-}\to {\nu }_{\tau }{\pi }^{-}{\pi }^0+n{h}^0(n>~1)$, where $h^0$ is a ${\pi }^0$ or an $\eta$. The data sample, obtained with the time-projection-chamber detector facility at the SLAC $e^{+}{e}^{-}$ storage ring PEP, corresponds to an integrated luminosity of 72 ${\mathrm{pb}}^{-1\mathrm{}}$ at 29 GeV center-of-mass energy. The measured branching fraction is somewhat greater than the theoretical prediction and, with errors taken into account, could resolve the present difference between the inclusive and the sum of the exclusive ${\tau }^{\pm }$ branching fractions into one charged prong.