ATLAS measurements of CP violation and rare decay processes with beauty mesons

The ATLAS experiment has performed measurements of $B$-meson rare decays proceeding via suppressed electroweak flavour changing neutral currents, and of mixing and CP violation in the neutral $B^{0}_{s}$ meson system. This talk will focus on the latest results from the ATLAS collaboration, such as rare processes $B^{0}_{s}\rightarrow\mu\mu$ and $B^{0}_{d}\rightarrow\mu\mu$ and CP violation in $B^{0}_{s}\rightarrow J/\psi\phi$decays. In the latter, the Standard Model predicts the CP violating mixing phase, $\phi_{s}$, to be very small and its SM value is very well constrained, while in many new physics models large $\phi_{s}$ values are expected. The latest measurements of $\phi_{s}$ and several other parameters describing the $B^{0}_{s}\rightarrow\mu\mu$ decays will be reported.