EPJ Web of Conferences 28, 04007 (2012)
https://doi.org/10.1051/epjconf/20122804007

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

Department of Physics, University of Oxford, Oxford, United Kingdom

^a e-mail: m.charles1@physics.ox.ac.uk

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⁻ 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^*− → decay chains. The difference in CP asymmetry between D⁰ → K⁻K⁺ and D⁰ → π⁻π⁺, ΔA_CP ≡ A_CP(K⁻K⁺) − A_CP(π⁻π⁺), is measured to be ΔA_CP = |−0.82 ± 0.21(stat.) ± 0.11(syst.)|%. This differs from the hypothesis of CP conservation by 3.5σ.