The Belle II Collaboration

27 July 2020

Abstract: In the standard model, mixing and CP violation in the charm sector are expected to be very small and thus they constitute a sensitive probe for potential new physics contributions. The "wrong-sign" decays D0->K+π−, K+π−π0, K+π−π+π− are among the best channels to study charm mixing, as they can be produced through two interfering processes: a direct doubly Cabibbo-suppressed decay of the D0 meson, or through D0-D0bar mixing followed by a Cabibbo-favored decay of the D0bar meson. This note reports the "rediscovery" of these three decays in the data collected by Belle II during 2019 and the first half of 2020, and corresponding to 37.8 fb−1 of integrated luminosity.