Investigation of edge radiation intensification effect generated by periodic alignment of three-pole wigglers

The intensification effect of edge radiation due to the periodic alignment of three-pole wigglers was analytically and numerically investigated. The radiation properties were studied using a simple model that had an alternating alignment of straight sections and large gradient orbit sections due to the use of three-pole wigglers. The angular distribution of the radiation was concentrated on a concentric circle. The peak intensity of the radiation was roughly on the same order as that of the peak radiation of a planar undulator. The spectrum of the radiation had a characteristic structure that was rather similar to the higher harmonic structure of undulator radiation. A numerical study showed that a planar undulator with a specific K value satisfies approximately the radiation intensification condition due to the periodic alignment of the three-pole wigglers. The intensified edge radiation is included in the undulator radiation.

Optical klystron undulator radiation with electromagnetic wave undulator

In the present study we proposed optical klystron in an electromagnet wave undulator. We consider the circularly polarized electromagnetic waves are travelling collinearly in opposite direction formed a beat wave. Spectral properties of the beat wave optical klystron are analysed and investigated using Lienard-Wiechert potential. We observed spikes as well as sidebands on the either side of the fundamental frequency.

A Review of High-Gain Free-Electron Laser Theory

High-gain free-electron lasers, conceived in the 1980s, are nowadays the only bright sources of coherent X-ray radiation available. In this article, we review the theory developed by R. Bonifacio and coworkers, who have been some of the first scientists envisaging its operation as a single-pass amplifier starting from incoherent undulator radiation, in the so called self-amplified spontaneous emission (SASE) regime. We review the FEL theory, discussing how the FEL parameters emerge from it, which are fundamental for describing, designing and understanding all FEL experiments in the high-gain, single-pass operation.