The resonant structure of the four pion final state in the decay $\overrightarrow{\tau }3\pi {\pi }^0{\nu }_{\tau }$ has been analyzed using 4.27 million ${\tau }^{+}{\tau }^{-}$ pairs collected by the CLEO II experiment at the Cornell Electron Storage Ring. A partial wave analysis of the resonant structure of the $\overrightarrow{\tau }3\pi {\pi }^0{\nu }_{\tau }$ decay has been performed; the spectral decomposition of the four pion system is dominated by the $\omega \pi$ and $a_1\pi$ final states. The mass and width of the ${\rho }^{\prime }$ resonance have been extracted from a fit to the $\overrightarrow{\tau }\omega \pi {\nu }_{\tau }$ spectral function. We have searched for second class currents in the decay $\overrightarrow{\tau }\omega \pi {\nu }_{\tau }$ using spin-parity analysis and established an upper limit on the non-vector current contribution.

• Received 30 September 1999

DOI:https://doi.org/10.1103/PhysRevD.61.072003