Searching for $D^0 \rightarrow K^- \pi^+ \eta^0$ in Belle Data

We describe the reconstruction of the CP- decay mode $D^0\rightarrow K^-\pi^+ \eta^0 $in the Belle I data set. Using a set of simulated signal and a generic simulated sample equal in size to the Belle I data set, we reconstructed 826 events from an initial sample of 18,900 simulated events for an efficiency of 4.4\%. We studied backgrounds in the generic simulated sample, and checked in the real data. We found, in agreement with the simulations, no obvious signal in the Belle I data indicating that further work has to go into suppressing the background.