Measurement of the charm-mixing parameter yCP in D0 → KS0 ω decays at Belle

Abstract

We report the first measurement of the charm-mixing parameter yCP in D0 decays to the CP-odd final state KS0ω. The study uses the full Belle e+e- annihilation data sample of 976 fb-1 taken at or near the (4S) centre-of-mass energy. We find yCP=(0.96±0.91±0.62-0.00+0.17)%, where the first uncertainty is statistical, the second is systematic due to event selection and background, and the last is due to possible presence of CP-even decays in the data sample.