Measurement of the $CP$-violating phase $\phi^{J/\psi\phi}_s$ using the flavor-tagged decay $B_s^0\rightarrow J/\psi\phi$ in $8\ \text{fb}^{-1}$ of $p\bar p$ collisions

Abstract

We report an updated measurement of the $CP$-violating phase, $\phi^{J/\psi\phi}_s$, and the decay-width difference for the two mass eigenstates, $\Delta\Gamma_s$, from the flavor-tagged decay $B^0_s\rightarrow J/\psi\phi$. The data sample corresponds to an integrated luminosity of $8.0\ \text{fb}^{−1}$ accumulated with the D0 detector using $p\bar p$ collisions at $\sqrt s=1.96 \text{TeV}$ produced at the Fermilab Tevatron collider. The 68% Bayesian credibility intervals, including systematic uncertainties, are $\Delta\Gamma_s=0.163^{+0.065}_{−0.064} \text{ps}^{−1}$ and $\phi^{J/\psi\phi}_s=−0.55^{+0.38}_{−0.36}$. The $p$-value for the Standard Model point is 29.8%.