Resonances and $CP$ violation in $B_s^0$ and $\overline{B}_s^0 \to J/\psi K^+K^-$ decays in the mass region above the $\phi(1020)$

The decays of B$_{s}^{0}$ and $ {\overline{B}}_s^0 $ mesons into the J/ψK$^{+}$ K$^{−}$ final state are studied in the K$^{+}$ K$^{−}$ mass region above the ϕ(1020) meson in order to determine the resonant substructure and measure the CP-violating phase, ϕ$_{s}$ , the decay width, Γ$_{s}$ , and the width difference between light and heavy mass eigenstates, ΔΓ$_{s}$ . A decay-time dependent amplitude analysis is employed. The data sample corresponds to an integrated luminosity of 3 fb$^{−1}$ produced in 7 and 8 TeV pp collisions at the LHC, collected by the LHCb experiment. The measurement determines ϕ$_{s}$ = 119 ± 107 ± 34 mrad. A combination with previous LHCb measurements using similar decays into the J/ψπ$^{+}$ π$^{−}$ and J/ψϕ(1020) final states gives ϕ$_{s}$ = 1 ± 37 mrad, consistent with the Standard Model prediction.