Study of partial cross sections of photo-ionisation of some simple molecules within the range of energy from 10 to 35 eV obtained from a synchrotron radiation

This research thesis reports the experimental study of the process of ejection of an electron or of ionisation of a neutral isolated molecule. The author mainly addresses partial cross sections of formation of fluorescent states in diatomic molecules. The oxygen molecule is addressed with the study of asymmetric resonances which appear at high energy (use of the Fano model). N₂ and CO molecules are then addressed. The case of triatomic molecules is reported with the measurement of photo-ionisation partial cross sections (like for diatomic molecules), and of cross sections related to photo-dissociation through the measurement of fluorescence of fragments