Observation of time-reversal violation in the B0 meson system

The individually named authors work collectively as The BABAR Collaboration. Copyright @ 2012 American Physical Society.Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B0 or B¯¯¯0), and J/ψK0L or cc¯K0S final states (referred to as B+ or B−), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, B¯¯¯0→B− and B−→B¯¯¯0, as a function of the time difference between the two B decays. Using 468×106 BB¯¯¯ pairs produced in Υ(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding ΔS+T=−1.37±0.14(stat)±0.06(syst) and ΔS−T=1.17±0.18(stat)±0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation.DOE and NSF (USA), NSERC (Canada), CEA and CNRS-IN2P3 (France), BMBF and DFG(Germany), INFN (Italy), FOM (The Netherlands), NFR (Norway), MES (Russia), MINECO (Spain), STFC (United Kingdom). Individuals have received support from the Marie Curie EIF (European Union), the A. P. Sloan Foundation (USA) and the Binational Science Foundation (USA-Israel)

Study of the K+ K- invariant-mass dependence of CP asymmetry in B+ → K+K-K+ decays

5 pages, 4 postscript figures, contributed to FPCP2013.As a followup to the latest BABAR amplitude analysis of the decay B+ → K+K-K+, we investigate the K+K- invariant-mass dependence of the CP asymmetry and compare it to that obtained by the LHCb collaboration. The results are based on a data sample of approximately 470 × 106BB decays, collected with the BABAR detector at the PEP-II asymmetric-energy B factory at the SLAC National Accelerator Laboratory.OEandNSF (USA), NSERC (Canada), CEAandCNRS-IN2P3 (France), BMBF and DFG (Germany), INFN (Italy), FOM (TheNetherlands), NFR (Norway), MES (Russia), MINECO (Spain), STFC (UnitedKingdom); individuals have received support from the Marie Curie EIF (European Union) and the A.P. Sloan Foundation (USA)