This book contains a systematic treatment of the basic principles of
free elec- tron laser (FEL) physics. It is primarily intended for
physicists specializing in FEL physics and related fields: laser
physics, microwave electronics, particle accelerator physics, etc. At
the same time it might be useful for those who use the FEL as a research
or industrial tool. The treatment requires that the reader has a
knowledge of classical me- chanics and electrodynamics. It is assumed
that the reader is familiar with the kinetic theory of charged particle
beams, in particular the Vlasov equa- tion. All the results presented
here are derived from "first principles", and all steps involving
physical principles are given. To preserve a self-consistent style, we
place the derivation of auxiliary results in appendices. Theoretical
study is performed with an extensive use of similarity tech- niques, so
the results obtained are simultaneously highly general and com- pletely
specified. The use of similarity techniques involves a particular way of
thinking and leads to a deeper insight into FEL physics. We use a
synthetic approach to present the material: some simple models are
studied first, and more complicated ones are introduced gradually. We
start with the one-dimensional theory of the FEL amplifier and FEL
oscilla- tor. Then we move on the analysis of diffraction effects and
waveguide effects. Finally, we introduce the reader to the part of FEL
theory dealing with the start-up from shot noise in the electron beam.
