Four-Pion Decay of thef0Meson

The reaction ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}{f}^{0}n\ensuremath{\rightarrow}2{\ensuremath{\pi}}^{+}2{\ensuremath{\pi}}^{\ensuremath{-}}n$ has been observed at 5 GeV/c with $\ensuremath{\sigma}=11.5\ifmmode\pm\else\textpm\fi{}4$ \ensuremath{\mu}b ($1.20l{m}_{4\ensuremath{\pi}}l1.32$, $|t|l0.2$ Ge${\mathrm{V}}^{2}$).