Search for $f_1(1285)\to {\pi }^{+}{\pi }^{-}{\pi }^0$ decay with VES detector

The isospin violating decay $f_1(1285)\to {\pi }^{+}{\pi }^{-}{\pi }^0$ has been studied at VES facility. This study is based at the statistics acquired in ${\pi }^{-}Be$ interactions at 27, 36.6 and 41 GeV/c in diffractive reaction $\pi^- N \to (f_1 \pi^-) N$\mathrm{.}The$f_1(1285) \to \pi^+\pi^-\pi^0$ decay is observed. The ratio of decay probabilities $BR(f_1(1285)\to {\pi }^{+}{\pi }^{-}{\pi }^0)$ to $BR(f_1(1285) \to \eta \pi^+\pi^-) \cdot BR(\eta \to \gamma\gamma)$is$\sim:1.4%$.