CP violation in Bs decays (CMS)

These proceedings presents the measurement of the weak CP-violating phase $\phi_s$ in the $B_s^0\to J/\psi\,\phi(1020)$ decay channel at 13 TeV with the CMS experiment. The measurement is based on a data sample corresponding to an integrated luminosity of 96.4 fb$^{-1}$, collected in 2017--2018. This analysis employs a dedicated tagging trigger and a novel opposite-side muon flavor tagger based on deep learning techniques.The decay width (mass) difference $\Delta\Gamma_s$ ($\Delta m_s$) between the light and heavy $B_s^0$ mass eigenstates, the $B_s^0$ average decay width $\Gamma_s$ and the CP violation observable $ \lambda$ are also measured. The combination with the results obtained by CMS at 8 TeV is also presented.