TY - JOUR
T1 - Observation of CP violation in the B° meson system
AU - Aubert, B
AU - Bright-Thomas, Paul
AU - Harrison, Theresa
AU - Hawkes, Christopher
AU - Knowles, David
AU - O'Neale, Stephen
AU - Penny, Richard
AU - Watson, Alan
AU - Watson, Nigel
PY - 2001/8/1
Y1 - 2001/8/1
N2 - 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 x 10(6) BB macro pairs. We select events in which one neutral B meson is fully reconstructed in a 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(0) meson system. We also determine absolute value of lambda = 0.93+/-0.09(stat)+/-0.03(syst), consistent with no direct CP violation.
AB - 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 x 10(6) BB macro pairs. We select events in which one neutral B meson is fully reconstructed in a 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(0) meson system. We also determine absolute value of lambda = 0.93+/-0.09(stat)+/-0.03(syst), consistent with no direct CP violation.
UR - https://www.scopus.com/pages/publications/0035959125
U2 - 10.1103/PhysRevLett.87.091801
DO - 10.1103/PhysRevLett.87.091801
M3 - Article
C2 - 11531560
SN - 1079-7114
VL - 87
SP - 091801
JO - Physical Review Letters
JF - Physical Review Letters
IS - 9
ER -