Estudo do decaimento $B \to D(K_{s}KK)K^{*}$ no experimento LHCb

This thesis has two independent parts: a study of a B meson decay mode and a contribution to the assembly of the experiment. The analysis describes the LHCb sensitivity to the decay $B^0 \to D^{0}(K^{0}_{s}K^{+}K^{-}) K^{*}(892)^0$. This decay can be used to extract the γ phase of CKM matrix, for which there is no conclusive measurement until now. The experimental contribution had been realized in the muon system, through the tests of the MWPC chambers, that will be installed at this system.