TY  - JOUR
AU  - LHCb Collaboration (Aaij, R. et al
AU  - Jaimes Elles, S. J.
AU  - Jashal, B. K.
AU  - Martinez-Vidal, F.
AU  - Oyanguren, A.
AU  - Rebollo De Miguel, M.
AU  - Ruiz Vidal, J.
AU  - Sanderswood, I.
AU  - Zhuo, J.
PY  - 2024
DA  - 2024//
TI  - Improved Measurement of CP Violation Parameters in B0s → J/ψ K+ K- Decays in the Vicinity of the φ(1020) Resonance
T2  - Phys. Rev. Lett.
JO  - Physical Review Letters
SP  - 051802
EP  - 12pp
VL  - 132
IS  - 5
PB  - Amer Physical Soc
AB  - The decay-time-dependent CP asymmetry in B0s -> J=psi(-> mu+mu-)K+K- decays is measured using proton-proton collision data, corresponding to an integrated luminosity of 6 fb-1, collected with the LHCb detector at a center-of-mass energy of 13 TeV. Using a sample of approximately 349 000 B0s signal decays with an invariant K+K- mass in the vicinity of the phi(1020) resonance, the CP-violating phase phi s is measured, along with the difference in decay widths of the light and heavy mass eigenstates of the B0s-B over bar 0s system, Delta Gamma s, and the difference of the average B0s and B0 meson decay widths, Gamma s – Gamma d. The values obtained are phi s = -0.039 +/- 0.022 +/- 0.006 rad, Delta Gamma s = 0.0845 +/- 0.0044 +/- 0.0024 ps-1, and -0.0015 +/- 0.0014 ps-1, where the first uncertainty is statistical and the second systematic. These are the most precise single measurements to date and are consistent with expectations based on the Standard Model and with the previous LHCb analyses of this decay. These results are combined with previous independent LHCb measurements. The phase phi s is also measured independently for each polarization state of the K+K- system and shows no evidence for polarization dependence.
SN  - 0031-9007
UR  - https://arxiv.org/abs/2308.01468
UR  - https://doi.org/10.1103/PhysRevLett.132.051802
DO  - 10.1103/PhysRevLett.132.051802
LA  - English
N1  - WOS:001190889800002
ID  - LHCbCollaborationAaij_etal2024
ER  -