Abstract: We present a measurement of the CP-violating parameter
J=c s using approximately 6500 B0s !J=c decays reconstructed with the CDF II detector in a sample of pp
collisions at ffiffisp ¼ 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=c s 2 ½0:02; 0:52[½1:08; 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=c KþK
final state which is found to be negligible over the mass interval 1:009 < mðKþK
Þ < 1:028 GeV=c2. Assuming the standard model prediction for the CP-violating phase
J=c s , we find the B0s decay width difference to be s ¼ 0:075 0:035ðstatÞ 0:006ðsystÞ ps
1. We also present the most precise measurements of the B0smean lifetime ðB0s Þ ¼ 1:529 0:025ðstatÞ 0:012ðsystÞ ps, the polarization fractions jA0ð0Þj2 ¼ 0:524 0:013ðstatÞ 0:015ðsystÞ and jAkð0Þj2 ¼ 0:231 0:014ðstatÞ 0:015ðsystÞ, as well as the strong phase ? ¼ 2:95 0:64ðstatÞ 0:07ðsystÞ rad. In addition, we report an alternative Bayesian analysis that gives results consistent with the frequentist approach.

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