Optimization of the CLIC positron source using a start-to-end simulation approach involving multiple simulation codes

A start-to-end optimization simulation toolkit for the CLIC positron source has been developed using multiple simulation codes to model adequately different areas of the positron source. The positron source includes the targets using channeling and pair-production processes, the adiabatic matching device and the pre-injector and injector linacs. The primary electron beams with energies of 5 GeV and 3 GeV are optimized with this toolkit as well as the target parameters. Finally rf parameters or the linear accelerators are optimized involving a particle tracking code. Using this approach the yield of the CLIC positron source has been increased by a factor 2 resulting in significant cost savings.