Seminars Archive

Echo-enabled Harmonic Generation Free Electron Laser

Abstract
The Echo-enabled Harmonic Generation (EEHG) FEL uses two modulators in
combination with two dispersion sections that allow one to generate in the beam
a high-harmonic density modulation starting with a relatively small initial
energy modulation of the beam. I address several practically important issues,
such as the effect of incoherent synchrotron radiation in the dispersion
sections, and the beam transverse size effect in the modulator. Using a
representative realistic set of beam parameters, I show how the EEHG scheme
enhances the FEL performance and allows one to generate a fully (both
longitudinally and transversely) coherent radiation. Finally, I will briefly
describe a new idea of generation of attosecond pulses of radiation using EEGH.