Time-Dependent Phenomena in Tapered Free-Electron Lasers
The MAX IV facility in Lund is scheduled to open in 2016. The facility uses electron accelerators to produce high-quality X-rays for different areas of scientific research. The design of the facility enables future expansion and the inclusion of a Free-Electron Laser (FEL) is part of the laboratory's long-term strategic plan. In this project, we study the physics of FELs by means of numerical simulations. First, we shall continue the work in our recent publication [Phys. Rev. ST Accel. Beams 18, 040702 (2015)]. In light of the Kroll-Morton-Rosenbluth model, we study the use of undulator tapering for FEL efficiency enhancement. Furthermore, we characterize the time-dependent phenomena which limit the efficiency of a tapered FEL. In addition, we explore a number of other FEL-related topics, such as the generation of ultrashort X-ray pulses and the application of emittance exchange beamlines.