A search for decay ${\eta }^{\mathrm{\prime }}\to 4{\pi }^0$ with GAMS-$4\pi$ Setup

A search for rare decay ${\eta }^{\mathrm{\prime }}\to 4{\pi }^0$ has been performed with GAMS-4$\pi$ Setup. The new upper limit for decay was established $BR(\eta’ \rightarrow 4 \pi^{0}) < 3.2 \cdot 10^{-4}$at90\mathrm{\%}confidencelevel\mathrm{.}The$\pi^{-} p$charge-exchangereactionat32.5GeV\mathrm{/}cwasusedasasourceof$1.3\cdot 10^{6}$ ${\eta }^{\mathrm{\prime }}$ mesons. Experiment carried out at the IHEP U-70 accelerator.