Measurement of CP observables in B± → D(*)K± and B± → D(*)π± decays using two-body D final states


Measurements of CP observables in B±D(*)K± and B±D(*)π± decays are presented, where D(∗) indicates a neutral D or D meson that is an admixture of meson and anti-meson states. Decays of the D(∗) meson to the 0 and final states are partially reconstructed without inclusion of the neutral pion or photon. Decays of the D meson are reconstructed in the K±π, K+K, and π+π final states. The analysis uses a sample of charged B mesons produced in proton-proton collisions and collected with the LHCb experiment, corresponding to integrated luminosities of 2.0, 1.0, and 5.7 fb1 taken at centre-of-mass energies of 7, 8, and 13 TeV, respectively. The measurements of partially reconstructed B±D(*)K± and B±D(∗)π± with DKπ± decays are the first of their kind, and a first observation of the B±\( {\left(D{\pi}^0\right)}_{D^{\ast }}{\pi}^{\pm } \) decay is made with a significance of 6.1 standard deviations. All CP observables are measured with world-best precision, and in combination with other LHCb results will provide strong constraints on the CKM angle γ.

A preprint version of the article is available at ArXiv.


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