A search for time-integrated CP violation in D0 → h -h+ decays

Abstract

The preliminary results of a search for time-integrated CP violation in D0 → h-h+ (h = K, π) decays performed with 0.6 fb-1 of data collected by LHCb in 2011 are presented. The flavour of the charm meson is determined by the charge of the slow pion in the D*+ → D0π+ and D+- → D0π- decay chains. The difference in CP asymmetry between D0 → KK+ and D0 → π-π+, ΔACP = ACP(K -K+) - ACP(π-π+), is measured to be ΔACP = [-0.82 ± 0.21(stat.) ± 0.11(syst.)] %. This differs from the hypothesis of CP conservation by 3.5σ. © Owned by the authors 2012.