Observation of CP Violation in the B{sup 0} Meson System
We present an updated measurement of time-dependent CP-violating asymmetries in neutral B decays with the BABAR detector at the PEP-II asymmetric B Factory at SLAC. This result uses an additional sample of {Upsilon}(4S) decays collected in 2001, bringing the data available to 32 million B{bar B} pairs. We select events in which one neutral B meson is fully reconstructed in final state containing charmonium and the flavor of the other neutral B meson is determined from its decay products. The amplitude of the CP-violating asymmetry, which in the Standard Model is proportional to sin2{beta}, is derived from the decay time distributions in such events. The result sin2{beta} = 0.59 {+-} 0.14 (stat) {+-} 0.05 (syst) establishes CP violation in the B{sup 0} meson system. We also determine |{lambda}| = 0.93 {+-} 0.09 (stat) {+-} 0.03 (syst), consistent with no direct CP violation.
- Research Organization:
- SLAC National Accelerator Lab., Menlo Park, CA (United States)
- Sponsoring Organization:
- USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC03-76SF00515
- OSTI ID:
- 787193
- Report Number(s):
- SLAC-PUB-8904; TRN: US0110461
- Resource Relation:
- Other Information: PBD: 25 Jul 2001
- Country of Publication:
- United States
- Language:
- English
Similar Records
A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)
Improved Measurement of the CP-Violating Asymmetry Amplitude sin2beta