A search for decay η' rightarrow 4 π⁰ with GAMS-4π Setup

A search for rare decay $\eta' \rightarrow 4 \pi^{0}$ has been performed with GAMS-4$\pi$ Setup. The new upper limit for decay was established $BR(\eta' \rightarrow 4 \pi^{0}) < 3.2 \cdot 10^{-4}$ at 90\% confidence level. The $\pi^{-} p$ charge-exchange reaction at 32.5 GeV/c was used as a source of $1.3\cdot 10^{6}$ $ \eta'$ mesons. Experiment carried out at the IHEP U-70 accelerator.