We report the result from the first search for $D^0$ decays to invisible final states. The analysis is performed on a data sample of $924{\mathrm{fb}}^{-1}$ collected at and near the $\mathrm{\Upsilon }(4S)$ and $\mathrm{\Upsilon }(5S)$ resonances with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. The absolute branching fraction is determined using an inclusive $D^0$ sample, obtained by fully reconstructing the rest of the particle system including the other charmed particle. No significant signal yield is observed and an upper limit of $9.4\times {10}^{-5}$ is set on the branching fraction of $D^0$ to invisible final states at 90% confidence level.

• Received 30 November 2016

DOI:https://doi.org/10.1103/PhysRevD.95.011102