- Aubert, B
- Boutigny, D
- Gaillard, JM
- Hicheur, A
- Karyotakis, Y
- Lees, JP
- Robbe, P
- Tisserand, V
- Palano, A
- Pompili, A
- Chen, GP
- Chen, JC
- Qi, ND
- Rong, G
- Wang, P
- Zhu, YS
- Eigen, G
- Stugu, B
- Abrams, GS
- Borgland, AW
- Breon, AB
- Brown, DN
- Button-Shafer, J
- Cahn, RN
- Clark, AR
- Gill, MS
- Gritsan, AV
- Groysman, Y
- Jacobsen, RG
- Kadel, RW
- Kadyk, J
- Kerth, LT
- Kolomensky, YG
- Kral, JF
- LeClerc, C
- Levi, ME
- Lynch, G
- Oddone, PJ
- Pripstein, M
- Roe, NA
- Romosan, A
- Ronan, MT
- Shelkov, VG
- Telnov, AV
- Wenzel, WA
- Harrison, TJ
- Hawkes, CM
- Knowles, DJ
- O'Neale, SW
- Penny, RC
- Watson, AT
- Watson, NK
- Deppermann, T
- Goetzen, K
- Koch, H
- Kunze, M
- Lewandowski, B
- Peters, K
- Schmuecker, H
- Steinke, M
- Barlow, NR
- Bhimji, W
- Chevalier, N
- Clark, PJ
- Cottingham, WN
- Foster, B
- Mackay, C
- Wilson, FF
- Abe, K
- Hearty, C
- Mattison, TS
- McKenna, JA
- Thiessen, D
- Jolly, S
- McKemey, AK
- Blinov, VE
- Bukin, AD
- Bukin, DA
- Buzykaev, AR
- Golubev, VB
- Ivanchenko, VN
- Korol, AA
- Kravchenko, EA
- Onuchin, AP
- Serednyakov, SI
- Skovpen, YI
- Telnov, VI
- Yushkov, AN
- Best, D
- Chao, M
- Kirkby, D
- Lankford, AJ
- Mandelkern, M
- McMahon, S
- Stoker, DP
- Arisaka, K
- Buchanan, C
- Chun, S
- MacFarlane, DB
- et al.
We present a measurement of time-dependent CP-violating asymmetries in neutral B meson decays collected with the BABAR detector at the PEP-II asymmetric-energy e +e - collider at the Stanford Linear Accelerator Center. The data sample consists of 29.7 fb -1 recorded at the γ(4S) resonance and 3.9 fb -1 off resonance. One of the neutral B mesons, which are produced in pairs at the γ(4S), is fully reconstructed in the CP decay modes J/ ψK S0, ψ(2S)K S0, χ c1K S0, J/ψK* 0 (K* 0→K S0π 0) and J/ψK L0, or in flavor-eigenstate modes involving D (*)π/p/a 1 and J/ψK* 0 (K* 0→K +π -). The flavor of the other neutral B meson is tagged at the time of its decay, mainly with the charge of identified leptons and kaons. A neural netsvork tagging algorithm is used to recover events without a clear lepton or kaon tag. The proper time elapsed between the decays is determined by measuring the distance between the decay vertices. Wrong-tag probabilities, the time-difference resolution function, and the B 0-B̄ 0 oscillation frequency Δm d are measured with a sample of about 6350 fully-reconstructed B 0 decays in hadronic flavor-eigenstate modes. A maximum-likelihood fit to this flavor eigenstate sample finds Δm d=0.516±0.016(stat)±0.010(syst) ps -1. The value of the asymmetry amplitude sin 2β is determined from a simultaneous maximum-likelihood fit to the time-difference distribution of the flavor-eigenstate sample and about 642 tagged B 0 decays in the CP-eigenstate modes. We find sin 2β=0.59 ±0.14(stat)±0. 05(syst), demonstrating that CP violation exists in the neutral B meson system. We also determine the value of the CP violation parameter |λ|=0. 93±0.09(stat)±0.03(syst), which is consistent with the expectation of |λ|=1 for no direct CP violation. © 2002 The American Physical Society.