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This thesis presents a measurement of the neutral charm meson mixing parameters and using , and decays. These parameters correspond to the departure from unity of the ratio of the effective decay widths of or decays over the effective decay width of decays. \The measurement is done with the dataset collected in the Run 2 (2015-2018) of the Large Hadron Collider (LHC) by the LHCb experiment at CERN at a centre-of-mass energy of , and corresponding to an integrated luminosity of . The mesons originate from decays. We measure \begin{equation} \begin{split} y_{C!P}^{KK} - y_{C!P}^{K\pi} & = (7.08 \pm 0.30 \pm 0.14) \times 10^{-3}, , \ y_{C!P}^{\pi\pi} - y_{C!P}^{K\pi} & = (6.57 \pm 0.53 \pm 0.16) \times 10^{-3}, , \end{split}\end{equation}where the first uncertainty is statistical while the second is systematic. Neglecting final state dependent contributions, we obtain the combination\begin{equation} y_{C!P} - y_{C!P}^{K\pi} = (6.96 \pm 0.26 \pm 0.13) \times 10^{-3} , .\end{equation}This measurement improves by a factor of four the precision of the current world average value of . In addition, the results allow for an improvement of the precision on the mixing parameter by a factor of two, where is connected to the width difference between the neutral charm meson mass eigenstates. The new world average value of is estimated to be\begin{equation} y = (6.45 \pm 0.24) \times 10^{-3} , .\end{equation}This thesis also presents the work done for the EPFL fibre mat production as part of the LHCb Scintillating Fibre (SciFi) Tracker upgrade.