title: CP violation effects on the measurement of the Cabibbo-Kobayashi-Maskawa angle γ from B→DK.
abstract: Inspired by the unexpectedly large difference between the CP violation of D decays into K(+)K(-) and π(+)π(-), we explore the impact on the extraction of γ via the B→DK process with the D meson reconstructed in the K(+)K(-), π(+)π(-) final state. We show that the extracted results for γ can be shifted by O(A(CP)/r(B)(K)), where A(CP) is the direct CP asymmetry in D decays and r(B)(K) is the ratio of the decay amplitudes of B(-)→D[over ¯](0)K(-) and B(-)→D(0)K(-). Using the recent data on CP asymmetry, we demonstrate that the correction to physical observables in B→DK can reach 6%, which corresponds to the shift of γ by roughly 5°. The remanent corrections depend on the strong phase of the D decays but are less than 0.5°. With the increasing precision in the γ determination on the LHCb experiment and the Super B factories, the inclusion of the CP violation of D decays will therefore soon become important.
authors: Helmholtz-Institut für Strahlen-und Kernphysik and Bethe Center for Theoretical Physics, Universität Bonn, D-53115 Bonn, Germany. weiwang@hiskp.uni-bonn.de
authors: Wei
authors: W
authors: Wang