Measurement of CP-violation parameters in decays of $B^0_s\to J/\psi\phi$ with the ATLAS detector

A measurement of CP-violating weak phase $\phi_s$ and $B^0_s$ meson decay width difference with $B^0_s\to J/\psi\phi$ decays in the ATLAS experiment is presented. It is based on integrated luminosity of 14.3 fb$^{-1}$ collected by the ATLAS detector from 8 TeV $pp$ collisions at the LHC. The measured values are statistically combined with those from 4.9 fb$^{-1}$ of 7 TeV collisions data, yielding an overall Run-1 ATLAS result.