The angular analysis of the $B^{0}\!\rightarrow\!K^{*0}\mu^{+}\mu^{-}$ decay at LHCb

The Standard Model (SM) of particle physics is an incomplete description of the fundamental particles and their interactions. In extensions of the SM, new physics particles are expected to appear at the TeV mass scale. The discovery of such new physics particles could help to answer some of the greatest questions in physics: what constitutes 'dark' matter; why is there more matter than antimatter; are there more than four dimensions? Particles at the TeV scale are expected to contribute virtually to interactions between SM particles at GeV energy scales. In interactions that are mediated by loop processes, such as the flavour-changing neutral current decay $ B^{0}\!\rightarrow\!K^{*0}\mu^{+}\mu^{-}$, the contribution from new physics particles can be as large as that of SM particles. Certain experimentally accessible observables of the $B^{0}\!\rightarrow\!K^{*0}\mu^{+}\mu^{-}$decay are precisely predicted in the SM and in new physics models. Any deviation in the measured value of the observables from the SM prediction would indicate a contribution from new physics particles. This thesis reports the analysis of the world's largest sample of $B^{0}\!\rightarrow\!K^{*0}\mu^{+}\mu^{-}$ decays. The decays are isolated in data collected at the LHCb experiment in the $\sqrt{s} = 7$ TeV $pp$ collisions at the Large Hadron Collider, corresponding to 1 fb$ ^{-1}$ of integrated luminosity. An angular analysis of the decays is performed to extract various observables. There is no significant deviation from the SM prediction in any of the measurements. The lack of new physics contributions to the $B^{0}\!\rightarrow\!K^{*0}\mu^{+}\mu^{-}$ decay indicates either that the new physics mass scale is significantly higher than 1 TeV or that the flavour couplings of the new physics particles are highly suppressed. These results impose stringent, model-independent constraints on new physics particles at the TeV mass scale.