Experimental studies for the validation of the opto-electronic components for the LHCb RICH Upgrade

The main aim of the LHCb experiment is to study rare decays and CP violation in hadrons containing b and c quarks. To increase these rare processes statistics, the LHCb experiment will be upgraded during the LHC technical shutdown of 2019/2020. The LHCb Ring Imaging Cherenkov (RICH) detector is responsible for the Particle Identification (PID) of the experiment, but the current Hybrid Photo Detectors (HPDs) and the readout electronics have to be replaced in order to comply with the 5-fold increase in instantaneous luminosity. In this thesis the test performed to validate the opto-electronic chain which will be installed in the upgraded RICH are presented. The CLARO ASIC is an 8-channel discriminator-amplifier which is the core component of the RICH Upgrade electronics and will read out the new Multi-Anode Photo Multiplier Tubes (MaPMTs). The CLARO radiation hardness has been validated using charged ion beams, proton beams and mixed irradiation field. The Total Ionizing Dose (TID) expected in the LHCb environment for the Run III + IV (2021-2029) duration is 200 krad, i.e. $3\times10^{12}$ 1-MeV n$_{eq}$/cm$^2$. The CLARO was tested for Single Event Effects (SEEs) using high Linear Energy Transfer (LET) ions in Louvain-La-Neuve and Legnaro, and a complete characterization of SEU and SEL was performed. In addition, the ASIC has been tested with 24 GeV/c protons up to a TID of 14 Mrad at the CERN IRRAD facility and in a mixed field environment at the CERN CHARM facility. A prototype of the LHCb RICH Upgrade detector has been tested at the North-Area at CERN using a 180 GeV/c charged hadron beam. Aim of the test was to test the full opto-electronic chain in a realistic environment and to characterize the CLARO behaviour in a system structurally close to the upgraded LHCb RICH setup. The RICH prototype, with the full opto-electronic chain, has been proved to work correctly in a realistic environment. In the last part of the thesis the validation tests on the LHCb RICH Upgrade opto-electronic components are reported. The components, CLAROs, Front-End Boards (FEBs) and Elementary Cells (ECs), have been validated using dedicated Quality Assurance (QA) procedures and test protocols. Dedicated analysis script have been developed to analyse the QA tests data. The results from the QA tests are used to create a complete characterization profile of the ECs performances. Dedicated files for each EC containing their most important parameters (of CLARO channels, MaPMTs and of all the other components) are created and will be loaded on the LHCb database to be used during the upgrade RICH commissioning.