High Extraction Free-Electron Laser Experiments.
Abstract
During this reporting period a tappered-wiggler free-electron laser experiment has ben constructed and initial energy extraction measurements have been made. the intent of the experiment is to demonstrate the high extraction capability of the tappered-wiggler free-electron laser. The hardware involves three primary elements: a two meter Sm Co5 permanent magnet wiggler, an RF linac operating at 20 MEV, and a 500 megawatt pulsed C02 laser. The FEL is operated in an amplifier configuration, with the electron and laser beams making a single simultaneous pass through the wiggler. The interaction of these beams is monitored by comparison of the electron energy spectrum with and without the presence of the C02 laser. The spectrum measurements are made using a round pole electron spectrometer. The wiggler wavelength is tappered such that the exit resonant energy is 9 percent below that at the entrance. The extraction measurements show that some electrons do decelerate 9 percent, in accordance with the taper, and that the net extraction is 2.5 percent. Extraction of 4 percent is expected when the overlap between electron and photon beams is improved. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 29, 1983
- Accession Number
- ADA129479