Laser-Pumped Coherent X-Ray FEL
Abstract
In a laser-pumped x-ray free electron laser (FEL) an intense laser field replaces the magnetic wiggler field of a conventional FEL. Depending on the intensity and quality of both the electron beam and pump laser, the Thomson backscattered radiation can be coherently amplified. in a conventional FEL, the generation of x-rays requires electron beam energies in the multi-GeV range. In a laser-pumped x-ray FEL, electron beam energies in the multi-MeV range would be sufficient. To generate coherent x-rays with this mechanism, a number of physics and technology issues must be addressed. Foremost among these are the stringent requirements placed on the electron beam quality and brightness as well as the pump laser intensity and pulse energy. The seed radiation for the laser-pumped FEL is the laser-induced spontaneous radiation. The evolution of incoherent radiation into coherent radiation as well as the power gain lengths associated with the coherent x-rays as a function of electron beam energy spread are analyzed and discussed. There is excellent agreement between our analytical results and GENESIS simulations for the radiated power, gain length, conversion efficiency, line-width and saturation length.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 14, 2008
- Accession Number
- ADA491178
Entities
People
- Bahman Hafizi
- Joseph R. Peñano
- Phillip A. Sprangle
Organizations
- United States Naval Research Laboratory