Optimization of SASE operation for an X-ray free-electron laser Using multiple objective evolutionary algorithms

635-641Performance of Self Amplifed Spontaneous Emission (SASE) operation for an X-ray Free-Electron Laser (FEL), is optimized by Multiple Objective Evolutionary Algorithms (MOEA). Different types of hybrid planar undulators are considered to achieve 0.5 Å ≤ λFEL ≤ 1.5 Å wavelength range. This demand is regarded as a continuous optimization problem, and hence, an evolutionary algorithm is designed to find optimal FEL performance parameters. An encoding scheme comprising of undulator period (λu) and undulator gap (g) is adopted here to find optimal values for saturation power (Psat) and λFEL subject to several physical constraints on λu and g such as the ratio of g/λu and Lsat. It is shown that MOEA gives optimal solutions for estimation of Lsat with plausible Psat values