Measurement of CP observables in $B^\pm \to D^{(*)} K^\pm$ and $B^\pm \to D^{(*)} \pi^\pm$ decays using two-body $D$ final states

Roel Aaij, Carlos Abellán Beteta, Thomas Ackernley, Bernardo Adeva, Marco Adinolfi, Hossein Afsharnia, Christine Angela Aidala, Salvatore Aiola, Ziad Ajaltouni, Simon Akar, Johannes Albrecht, Federico Alessio (+956 others)
2020
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 Dπ 0 and Dγ 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
more » ... in proton-proton collisions and collected with the LHCb experiment, corresponding to integrated luminosities of 2.0, 1.0, and 5.7 fb −1 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 D → K ∓ π ± decays are the first of their kind, and a first observation of the B ± → (Dπ 0 ) D * π ± 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. Published in JHEP 04 (2021) 081. © 2021 CERN for the benefit of the LHCb collaboration. CC BY 4.0 licence. † Authors are listed at the end of this paper. arXiv:2012.09903v2 [hep-ex] 15 Apr 2021 ii Kπ,γ/π 0 K/π observable is an average over the D * → Dπ 0 and D * → Dγ modes. Observable Definition A CP,γ
doi:10.18154/rwth-2021-05158 fatcat:gfjfhpsrerf7xdf75x5rf566uq