X-Ray Free-Electron Lasers: Technical Realization and Experimental Results

Abstract

AbstractThe physical and technological challenges of FELs become quite demanding with decreasing wavelength, but in recent years X-ray FELs with wavelengths in the Ångstrøm regime (1 Å \(=\) 0.1 nm \(=\,10^{-10}\,\)m) have become a reality with the successful commissioning and operation of the “Linac Coherent Light Source” LCLS [1], the world’s first FEL providing atomic resolution. In this chapter, we discuss the most important aspects and challenges of X-ray FELs and present some of the excellent experimental results achieved at LCLS and the second facility of this kind, the “Spring-8 Angstrom Compact free-electron LAser” SACLA [2]. Low-gain FEL oscillators in the X-ray regime have been proposed [3] but not yet demonstrated, they are not considered here. Comprehensive information and technical details on X-ray FELs are found in the design reports of LCLS [4] and the European XFEL [5]. Further valuable information is presented in a review article by Huang and Kim [6].KeywordsElectron BunchPeak BrightnessUndulator RadiationBunch ChargeLinac Coherent Light SourceThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.