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Rare decays of light mesons may be a discovery window for a new weaklycoupled forces hidden at low energy QCD scale. BES-III Collaboration reportedthe observation of the rare decay $\eta'\rightarrow\pi^0\gamma\gamma$. Theobserved decay width disagrees with the preliminary theoretical estimations. Weshow that this tension may be attributed to the New Physics, presumably DarkPhoton.  For completeness, we consider the possible influence of the New Physics on asimilar well-measured decay $\eta\rightarrow\pi^0\gamma\gamma$ and a recentlymeasured one $\eta' \rightarrow \eta\gamma\gamma$ and show that the impact ofthe hypothetical Dark Photon may be also present in these decays also.

The problems of $\eta'\rightarrow\pi^0\gamma\gamma$ decay and the New Physics