Undulator Tolerance Study for 0.1 nm PAL XFEL

MasterA tolerance study of the undulator parameter error for the 0.1 nm X-ray Free Electron Laser at Pohang AcceleratorLaboratory (PAL XFEL) has been performed and the results are presented in this paper. Effects of random and periodic errors on the FEL performance have been investigated, especially on the saturation power and saturation length. Periodic errors include sinusoidal and sawtooth forms. The study assumes non-steering errorbecause it can be cured by beam-based alignment technique. As a result, we found that an rms 0.05% random error of undulator K increases the saturation length approximately by 2% and decreasesthe satuation power by 6%