From detectors to data: Thermal Characterization of CMS Outer Tracker modules and Measurement of the top quark mass using $t$$\overline{t}$$\large{+}$ jet events

This thesis addresses key challenges in modern particle physics by contributing to three critical areas: the development of particle detectors, their calibration and the analysis of data collected in particle physics experiments. Contributions to these areas are presented in the context of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC). The frst part of this work focuses on the development and characterization of a temperature test system (Burn-in) for silicon modules, essential components of the CMS Outer Tracker Upgrade, a central part of the preparation of CMS for the forthcoming High Luminosity LHC running. The Burn-in test involves subjecting the modules to thermal cycling to identify early failures and ensure long-term reliability. This system demonstrated a reliable performance for quality assurance and has been used to conduct thermal characterization measurements of Pixel-Strip modules. In addition, thermal measurements including dees and cooling structures have been performed. In the second part of this thesis, the contribution to the CMS tracker alignment in the ongoing LHC run at a center of mass energy $\sqrt{s}$=13.6 TeV is presented. Alignment is a critical calibration process that ensures the high precision geometry required for accurate particle tracking. Special attention is given to the interplay between alignment and local pixel reconstruction. The final part of the thesis presents a measurement of the top quark pole mass, using events where the top quark-antiquark pairs are produced in association with an energetic jet ($t$$\overline{t}$$\large{+}$jet). The proton-proton collision data at $\sqrt{s}$=13 TeV are used, collected by the CMS and corresponding to the integrated luminosity of 138 fb$^{-1}$. This analysis employs machine learning-based techniques to reconstruct the $t$$\overline{t}$ kinematics. The top quark pole mass is extracted through comparison of the normalized diferential cross section of $t$$\overline{t}$$\large{+}$ production to the theoretical prediction in quantum chromodynamics at next-to-leading order. The result of this thesis improves the precision of the available CMS public result by a factor of 2 and is the most precise extraction of the top quark pole mass by using $t$$\overline{t}$$\large{+}$jet production, to date.