Thesis

Micromegas detectors are gaseous detectors used in particle physics and nuclear physics. Optical readout consists of observing, with a camera, the light emitted during electron amplification inside the detector. This technique opens up new possibilities for visualising ionisation and reconstructing events, particularly particle trajectories. However, the gas mixtures used often rely on CF4, a gas with a high global warming potential, motivating the search for alternative solutions.
The aim of this PhD project is to develop a new generation of optical Micromegas detectors capable of reconstructing events on an event-by-event basis, while improving detector performance and sustainability. The work will focus on optimising light production and collection, developing image reconstruction algorithms, and investigating wavelength-shifting materials. These materials could enable the use of CF4-free gas mixtures. Their ageing and long-term stability will also be studied. Finally, a gas recirculation and purification system will be developed to reduce gas consumption.
The expected outcomes include demonstrating new optical event reconstruction capabilities, validating solutions to reduce or eliminate the use of CF4, and developing a more efficient and sustainable detector prototype. These advances could find applications in neutron imaging, beta imaging and particle physics.