The new Large-area MicroMegas detector for AMBER experiment at CERN

The Apparatus for Mesons and Baryons Experimental Research (AMBER) experiment at Conseil Européen pour la Recherche Nucléaire (CERN) - Super Proton Synchrotron (SPS) aims at addressing fundamental questions in hadron structure and Quantum Chromodynamics (QCD), exploiting the unique capabilities of the M2 beam line. The physics programme of AMBER requires high-performance tracking detectors capable of operating at high particle fluxes while ensuring excellent spatial resolution, stability, and radiation tolerance. This thesis presents the design, development, and first test of a new Large-area MicroMegas (LMM) detector conceived to replace part of the existing Multi-Wire Proportional Chambers in the AMBER spectrometer. The work covers the full development chain, from detector concept and mechanical design to signal simulation, prototype construction, laboratory characterization, and beam test campaigns. The first chapter provides an overview of the AMBER experiment, outlining its physics programme and describing the main elements of the experimental apparatus and operating environment in which this thesis work was carried out. The second chapter presents an overview of gaseous detector technology: from wire chambers to Micro-Pattern Gaseous Detectors (MPGD). It provides the necessary background and motivation for the detector development described in this thesis. The third chapter constitutes the core of this work and is dedicated to the development and experimental validation of the LMM detector. It details the detector design, development and readout optimisation. Furthermore, simulation studies were performed with Garfield++. Concluding with and the characterization of the first full-size prototype of the LMM’s lateral module which was mainly carried out during the 2024 and 2025 test beam campaigns. 2 In parallel, the fourth chapter of this thesis reports on complementary activities within the AMBER upgrade program, including a detailed procedure for the refurbishment of existing multi-wire proportional chambers (MWPCs) and their integration with the new front-end electronics. The final chapter is dedicated to the readout electronics. It presents the studies performed on the Turin Integrated Gem Electronics for Readout (TIGER)- based readout system, focusing on the development and validation of a new front-end configuration compatible with the AMBER Large-area Micromegas detector. Building upon the extensive experience gained during the test of the TIGER Application Specific Integrated Circuit (ASIC), which has been developed in the context of BESIII experiment, the chapter also describes the design considerations for the newly developed Torino Readout for AMBER (ToRA) ASIC. The first characterization and integration tests of ToRA ASIC under beam conditions are presented, marking the initial validation of the front-end solution chosen for AMBER. The results proved the feasibility of the large-area micromegas detector as a solution for large-area tracking applications, establishing it as a strong candidate for the future upgrade of the AMBER experiment.