We present a measurement of the CP-violating parameter beta(s)(J/psi phi) using approximately 6500 B-s(0) -> J/psi phi decays reconstructed with the CDF II detector in a sample of p (p) over bar collisions at root s = 1.96 TeV corresponding to 5.2 fb(-1) integrated luminosity produced by the Tevatron collider at Fermilab. We find the CP-violating phase to be within the range beta(s)(J/psi phi) of [0.02, 0.52] OR [1.08, 1.55] at 68% confidence level where the coverage property of the quoted interval is guaranteed using a frequentist statistical analysis. This result is in agreement with the standard model expectation at the level of about one Gaussian standard deviation. We consider the inclusion of a potential S-wave contribution to the B-s(0) -> J/psi K+K- final state which is found to be negligible over the mass interval 1.009 < m(K+K-) < 1.028 GeV/c(2). Assuming the standard model prediction for the CP-violating phase beta(s)(J/psi phi), we find the B-s(0) decay width difference to be Delta Gamma(s) = (0.075 +/- 0.035(stat) +/- 0.006(syst)) ps(-1). We also present the most precise measurements of the B-s(0) mean lifetime tau(B-s(0)) = (1.529 +/- 0.025(stat) +/- 0.012(syst)) ps, the polarization fractions |A(0)(0)|(2) = 0.524 +/- 0.013(stat) +/- 0.015(syst) and |A(parallel)(0)|(2) = 0.231 +/- 0.014(stat) +/- 0.015(syst), as well as the strong phase delta(perpendicular) = 2.95 +/- 0.64(stat) +/- 0.07(syst) rad. In addition, we report an alternative Bayesian analysis that gives results consistent with the frequentist approach.
|Titolo:||Measurement of the CP-violating phase beta(s)(J/psi phi) in B-s(0) -> J/psi phi decays with the CDF II detector|
|Citazione:||T., A., B., Á.G., S., A., D., A., A., A., A., A., et al. (2012). Measurement of the CP-violating phase beta(s)(J/psi phi) in B-s(0) -> J/psi phi decays with the CDF II detector. PHYSICAL REVIEW. D. PARTICLES, FIELDS, GRAVITATION, AND COSMOLOGY, 85(7), 072002-1-072002-32.|
|Appare nelle tipologie:||1.1 Articolo in rivista|