Measurement of the CP-violating phase φ_s^(J/psi φ) at D0

This paper is a report of an updated measurement of the CP-violating phase and the decay width difference for the two mass eigenstates from flavor-tagged decay Bs0 to J/psi phi}. The 68% confidence level intervals, including systematic uncertainties, are phi_s=-0.55 ^{+0.38}_{-0.36}$ and \Delta \Gamma_s = 0.163 ^{+0.065}_{-0.064}$ ps^{-1}. This measurement is in agreement with SM expected value, the p-value for the Standard Model point is 29.8%. The data sample corresponds to an integrated luminosity of 8.0 fb^{-1} accumulated with the D0 detector at the Fermilab Tevatron collider.