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

We report an updated measurement of the CP-violating phase, $\phi_s^{J/\psi \phi}$,andthedecay-widthdifferenceforthetwomasseigenstates,$\Delta \Gamma_s$,fromtheflavor-taggeddecay$B_s^0 \rightarrow J/\psi \phi$. The data sample corresponds to an integrated luminosity of 8.0 fb${}^{-1}$ accumulated with the D0 detector using $p\text{barp}$ collisions at $\sqrt{s} = 1.96$ TeV produced at the Fermilab Tevatron collider. The 68% confidence level intervals, including systematic uncertainties, are $\Delta \Gamma_s = 0.163 +0.065 -0.064 ps^{-1}$and$\phi_s^{J/\psi \phi} = -0.55 +0.38 -0.36$\mathrm{.}The$p$-value for the Standard Model point is 29.8%.