Analysis of flavour mixing and CP violation in the strange-beauty meson system using LHCb data

This research analysed the flavour mixing and CP violation in the $B_s^0$ meson system using LHCb data for the $B_s^0 \rightarrow D_s^- \pi^+$ and $B_s^0 \rightarrow D_s^{\mp} K^{\pm}$ decays. The available data was filtered using the available detector reconstruction parameters, and fitted with theoretical functions to extract fundamental parameters of nature. Mass plots for the $B_s^0$ and $D_s^{\mp}$ mesons were created, together with decay-time distributions, flavour mixing and CP-asymmetry plots. $\Delta m_s$ was found to be $(17.732 \pm 0.042)\cdot10^{12} s^{-1}$ and $\Delta\Gamma_s=(0.00 \pm 0.35)\cdot10^{12} s^{-1}$, where the natural units $\hbar \equiv c \equiv 1$. The obtained master equation parameters do not deviate significantly from 0, so no CP violation was observed. Further improvements could be the use of more sophisticated fitting software, for example RooFit, and a more extensive background contribution modelling.