Search for $D^0$ decays to invisible final states at Belle

Abstract

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 $\hat{I}\yen (4S)$ and $\hat{I}\yen (5S)$ 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.

17 pages, 4 figures, submitted to PRD(RC)