Search for the decay ${D}^{0}\to {\pi }^{0}\nu \overline{\nu }$

We present the first experimental search for the rare charm decay ${D}^{0}\to {\pi }^{0}\nu \overline{\nu }$. It is based on an ${e}^{+}{e}^{-}$ collision sample consisting of $10.6×{10}^{6}$ pairs of ${D}^{0}{\overline{D}}^{0}$ mesons collected by the BESIII detector at $\sqrt{s}=3.773\text{}\text{}\mathrm{GeV}$, corresponding to an integrated luminosity of $2.93\text{}\text{}{\mathrm{fb}}^{-1}$. A data-driven method is used to ensure the reliability of the background modeling. No significant ${D}^{0}\to {\pi }^{0}\nu \overline{\nu }$ signal is observed in data and an upper limit of the branching fraction is set to be $2.1×{10}^{-4}$ at the 90% confidence level. This is the first experimental constraint on charmed-hadron decays into dineutrino final states.