In collaboration with the Thomas Jefferson Laboratory (JLab) in the USA, the researchers in the laboratory of nucleon structure at Irfu want to understand how quarks and gluons interact to form hadrons such protons, neutrons and pions. At JLab, a 11-GeV electron beam is impinged on a proton target. The protos are constituted of three quarks surrounded by a cloud of quark/antiquark pairs whose quantum numbers are similar to pions. The electrons of the beam will interact with these pairs with a structure analogous to a pion. More specifically, we are interested in the deeply virtual Compton scattering (DVCS) giving correlations between longitudinal momentum and transverse position of quarks in a pion. In other words, we are going to perform the very first 3D study of the pion structure. The PhD student will analyze data already available to isolate the DVCS events. A digital twins of the Monte-Carlo simulation/reconstruction chain will be produced with a conditional Generative Adversarial Network in order to caracterize faster and more accurately the background and, in the end, subtract it. The PhD student will travel two to three times a year to JLab, participating to the data taking as well as attending the collaboration meeting. The results will be presented in international conferences and published in peer-reviewed journals.