On Free-Electron Laser Growing Modes and their Bandwidth
Abstract
Free-electron lasers play an increasing role in science, from generating unique femtosecond X- ray pulses for single short recording of the protein structures to amplifying feeble interactions in advanced cooling systems for high-energy hadron colliders. While modern Free-electron laser codes can describe their amplification mechanism, a deep analytical understanding of the mechanism is of extreme importance for a number of applications. Mode competition, their growth rates and amplification bandwidth are among the most important parameters of a free-electron laser. A dispersion relation, which defines these important characteristics, can be solved analytically only for a very few simple cases. In this letter we show that for a typical bell-shape energy distribution in electron beam there is no more that one growing mode. We also derive an analytical expression which determines the bandwidth of the free-electron laser.
Cite
@article{arxiv.1105.0412,
title = {On Free-Electron Laser Growing Modes and their Bandwidth},
author = {Stephen Webb and Gang Wang and Vladimir Litvinenko},
journal= {arXiv preprint arXiv:1105.0412},
year = {2015}
}
Comments
4 pages, submitted to PRL