Abstract
The time-dependent CP asymmetry in Bs0→J/ψK +K - decays is measured using pp collision data at √s=7 TeV, corresponding to an integrated luminosity of 1.0 fb -1, collected with the LHCb detector. The decay-time distribution is characterized by the decay widths Γ L and Γ H of the light and heavy mass eigenstates of the Bs0-B̄s0 system and by a CP-violating phase s. In a sample of 27 617 Bs0→J/ψK +K - decays, where the dominant contribution comes from Bs0→J/ψ decays, these parameters are measured to be s=0.07±0.09(stat) ±0.01(syst) rad, Γ s≡(Γ L+Γ H)/2=0.663±0.005(stat)±0.006(syst) ps -1, and ΔΓ s≡Γ L-Γ H=0. 100±0.016(stat)±0.003(syst) ps -1, corresponding to the single most precise determination of s, ΔΓ s, and Γ s. The result of performing a combined analysis with Bs0→J/ψπ +π - decays gives s=0.01±0.07(stat)±0.01(syst) rad, Γ s= 0.661±0.004(stat)±0.006(syst) ps -1, and ΔΓ s=0.106±0.011(stat)±0.007(syst) ps -1. All measurements are in agreement with the Standard Model predictions.
Original language | English |
---|---|
Article number | 112010 |
Journal | Physical Review D - Particles, Fields, Gravitation and Cosmology |
Volume | 87 |
Issue number | 11 |
DOIs | |
Publication status | Published - 21 Jun 2013 |
Externally published | Yes |
Bibliographical note
Copyright:Copyright 2013 Elsevier B.V., All rights reserved.
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)