Measurement of the Semileptonic CP Asymmetry in B0-B̄0 Mixing
نویسنده
چکیده
The semileptonic CP asymmetry in B-B̄ mixing, asl, is measured in proton-proton collision data, corresponding to an integrated luminosity of 3.0 fb−1, recorded by the LHCb experiment. Semileptonic B decays are reconstructed in the inclusive final states D−μþ and D −μþ, where the D− meson decays into theKþπ−π− final state and theD − meson into the D̄0ð→ Kþπ−Þπ− final state. The asymmetry between the numbers ofDð Þ−μþ andDð Þþμ− decays is measured as a function of the decay time of the B mesons. The CP asymmetry is measured to be asl 1⁄4 ð−0.02 0.19 0.30Þ%, where the first uncertainty is statistical and the second systematic. This is the most precise measurement of asl to date and is consistent with the prediction from the standard model.
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