We present a measurement of the CP-violating parameter _J/ _s
using approximately 6500B0s ! J/ _ decays reconstructed with the CDF II
detector in a sample of p??p collisions at ps = 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
_J/ _s 2 [0.02, 0.52] [ [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 B0s
! J/ K+K??? final state which is found to be negligible over the mass
interval 1.009 < m(K+K???) < 1.028 GeV/c2. Assuming the
standard model prediction for the CP-violating phase _J/ _s , we find
the B0s decay width difference to be _????s = 0.075 ?? 0.035 (stat)
?? 0.006(syst) ps???1. We also present the most precise measurements of
the B0s mean lifetime _ (B0s ) = 1.529 ?? 0.025 (stat) ?? 0.012 (syst)
ps, the polarization fractions|A0(0)|2 = 0.524??0.013 (stat)??0.015
(syst) and |Ak(0)|2 = 0.231??0.014(stat)??0.015 (syst), as well as the
strong phase _? = 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.
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Updated: Thursday, 2012 April 26 11:40:31 CDT automatically from input from Stephanie A Schuler