Observation of $\psp$ decays to $\rho (770)\pi$ and $\rho (2150)\pi$

BES Collaboration, M. Ablikim

\pspto ρπis observed for the fisrt time in a data sample of 14M \psp decays collected by the BESII detector at BEPC. The branching fraction is measured to be \BR(psptoρπ)=(5.1+-0.7…