Optimization design of photo-injector using genetic algorithm

Maintaining and preserving a high density of particles in phase-space is an important requirement for the high brightness beams. In this paper, a photo-injector is optimized based on Dalian Coherent Light Source (DCLS) linac by using genetic algorithm (GA). Compared with traditional optimization methods, the great advantage of GA is its high efficiency with greater accuracy. In the GA optimization, it is convenient to transform the multi-objective problem into a single-objective optimization by using the weight factor. Because of the beam stability requirements for photo-injector, it is of interest to control the arrival time jitter within 150 fs by adopting GA optimization.