6D Phase space optimisation for high brightness electron beams in RF linacs as drivers for high brilliance inverse compton X and Y ray sources

X and gamma ray Inverse Compton sources are among the most performing devices in producing radiation with short wavelength, high power, ultrashort time duration, large transverse coherence and tunability. The expertise coming from the R&D activity on high brightness linear accelerators and high quality high power ps laser system enables today a transition phase towards the era of effective user facilities in X-ray imaging and gamma-ray Nuclear Physics and Photonics. Those sources require strong constrains for the electron beam: the minimization of both the transverse normalized emittance and the energy spread allows to maximize the spectral density and to guarantee the mono chromaticity of the emitted radiation. In this Ph.D. thesis a detailed study is presented on the 6D phase space optimisation for high brigthness electron beams in RF linacs as drivers for advanced and high brilliance Inverse Compton sources. In particular this work focuses on the beam dynamics studies for the ELI-NP Gamma Beam System (GBS) RF linac, currently in its delivering phase in Magurele (Romania), and on the commissioning phase of the SPARC LAB Thomson Source electron beamline at INFN-LNF in Frascati.