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Charmed hadron spectroscopy is a quickly progressing field that has enjoyed a growing interest in recent years from both theorist and experimentalists. Open-charmed hadrons consist of a heavy quark bound to a light quark (, , quarks). These particles are in particular spin-parity states making for a very interesting quantum mechanical system allowing the study of the QCD potential holding them together. Decays of type offer a rich environment to study charmed spectroscopy thanks to their abundance and low background. Using collision data at 7, 8, and 13 TeV center-of-mass energies corresponding to an integrated luminosity of collected with the LHCb detector at CERN's Large Hadron Collider, this thesis presents the most accurate measurement to-date of four branching fraction ratios of modes. These are measured to be \begin{equation*} \begin{split} \frac{\mathcal{B} (B^+ \rightarrow D^{+}D^-K^+)}{\mathcal{B} (B^+ \rightarrow \overline{D}^{0}D^0K^+)} &= 0.590 \pm 0.017 (\mathrm{stat}) \pm 0.008 (\mathrm{syst}) \pm 0.013 (\mathcal{B}(D)) , \[10pt] \frac{\mathcal{B} (B^+ \rightarrow D^{-}D^+K^+)}{\mathcal{B} (B^+ \rightarrow \overline{D}^{0}D^0K^+)} &= 0.524 \pm 0.015 (\mathrm{stat}) \pm 0.007 (\mathrm{syst}) \pm 0.012 (\mathcal{B}(D)) , \[10pt] \frac{\mathcal{B} (B^0 \rightarrow D^{-}D^0K^+)}{\mathcal{B} (B^0 \rightarrow D^{-}D^0K^+} &= 1.767 \pm 0.028 (\mathrm{stat}) \pm 0.018 (\mathrm{syst}) \pm 0.036 (\mathcal{B}(D)) , \[10pt] \frac{\mathcal{B} (B^+ \rightarrow D^{+}D^-K^+)}{\mathcal{B} (B^+ \rightarrow D^{-}D^+K^+)} &= 1.098 \pm 0.040 (\mathrm{stat}) \pm 0.017 (\mathrm{syst}), \end{split} \end{equation} where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the meson decay branching fractions measured by other experiments. Furthermore, this thesis shows the Dalitz plots of the final states for these decay modes using data samples an order of magnitude larger than samples collected by other experiments. These measurements are an important step towards a full amplitude analysis of decays.
In addition, this thesis summarizes the installation and studies of the BCAM system used to monitor the position of the Inner Tracker detector of LHCb.
Jian Wang, Matthias Finger, Qian Wang, Yiming Li, Matthias Wolf, Varun Sharma, Yi Zhang, Konstantin Androsov, Jan Steggemann, Leonardo Cristella, Xin Chen, Davide Di Croce, Rakesh Chawla, Matteo Galli, Anna Mascellani, João Miguel das Neves Duarte, Tagir Aushev, Lei Zhang, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Siyuan Wang, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Kun Shi, Wei Shi, Abhisek Datta, Jian Zhao, Federica Legger, Gabriele Grosso, Ji Hyun Kim, Donghyun Kim, Zheng Wang, Sanjeev Kumar, Wei Li, Yong Yang, Geng Chen, Ajay Kumar, Ashish Sharma, Georgios Anagnostou, Joao Varela, Csaba Hajdu, Muhammad Ahmad, Ekaterina Kuznetsova, Ioannis Evangelou, Muhammad Shoaib, Milos Dordevic, Meng Xiao, Sourav Sen, Xiao Wang, Kai Yi, Jing Li, Rajat Gupta, Zhen Liu, Muhammad Waqas, Hui Wang, Seungkyu Ha, Long Wang, Pratyush Das, Miao Hu, Anton Petrov, Xin Sun, Xin Gao, Chen Chen, Valérie Scheurer, Giovanni Mocellin, Muhammad Ansar Iqbal, Lukas Layer
Tatiana Pieloni, Claudia Tambasco
Jian Wang, Matthias Finger, Qian Wang, Yiming Li, Matthias Wolf, Varun Sharma, Yi Zhang, Konstantin Androsov, Jan Steggemann, Leonardo Cristella, Xin Chen, Davide Di Croce, Rakesh Chawla, Matteo Galli, Anna Mascellani, João Miguel das Neves Duarte, Tagir Aushev, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Siyuan Wang, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Kun Shi, Abhisek Datta, Jian Zhao, Federica Legger, Gabriele Grosso, Ji Hyun Kim, Donghyun Kim, Zheng Wang, Sanjeev Kumar, Wei Li, Yong Yang, Geng Chen, Ajay Kumar, Ashish Sharma, Georgios Anagnostou, Joao Varela, Csaba Hajdu, Muhammad Ahmad, Ekaterina Kuznetsova, Ioannis Evangelou, Muhammad Shoaib, Milos Dordevic, Meng Xiao, Sourav Sen, Xiao Wang, Kai Yi, Jing Li, Rajat Gupta, Muhammad Waqas, Hui Wang, Seungkyu Ha, Long Wang, Pratyush Das, Miao Hu, Anton Petrov, Xin Sun, Xin Gao, Valérie Scheurer, Giovanni Mocellin, Muhammad Ansar Iqbal, Lukas Layer