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Search for the rare decay $η'\rightarrowπ^{0}π^{0}π^{0}π^{0}$ at BESIII

Based on a sample of 1.31 billion $J/ψ$ events collected with the BESIII detector, we perform a search for the rare decay $η&#39;\rightarrow 4π^{0}$ via $J/ψ\rightarrowγη&#39;$. No significant $η&#39;$ signal is observed in the invariant mass spectrum of 4$π^{0}$. With a Bayesian approach, the upper limit on the branching fraction of $η&#39;\rightarrow 4π^{0}$ is determined to be $\mathcal{B}(η&#39;\rightarrow 4π^{0})$ $< 4.94\times10^{-5}$ at the 90\% confidence level, which is a factor of six smaller than the previous experimental limit.