| Literature DB >> 19905644 |
X J Wang1, H P Freund, D Harder, W H Miner, J B Murphy, H Qian, Y Shen, X Yang.
Abstract
We report the first experimental characterization of efficiency and spectrum enhancement in a laser-seeded free-electron laser using a tapered undulator. Output and spectra in the fundamental and third harmonic were measured versus distance for uniform and tapered undulators. With a 4% field taper over 3 m, a 300% (50%) increase in the fundamental (third harmonic) output was observed. A significant improvement in the spectra with the elimination of sidebands was observed using a tapered undulator. The experiment is in good agreement with predictions using the MEDUSA simulation code.Year: 2009 PMID： 19905644 DOI： 10.1103/PhysRevLett.103.154801
Source DB: PubMed Journal: Phys Rev Lett ISSN： 0031-9007 Impact factor: 9.161