CERN Accelerating science

Article
Title	Sub-Terawatt Mode of Operation of X-ray SASE FEL
Author(s)	Saldin, Evgeny L ; Schneidmiller, Evgeny A ; Yurkov, Mikhail V
Affiliation	(DESY, Hamburg)
Publication	2004
In:	26th International Free Electron Laser Conference and 11th FEL User Workshop 2004, Trieste, Italy, 29 Aug - 3 Sep 2004, pp.e-proc. MOPOS14
Subject category	Accelerators and Storage Rings
Abstract	Application of dispersion section in combination with undulator tapering is an effective tool for achieving extremely high output power of XFEL. In the first part of the undulator the gap is fixed, and amplification process is developed as in usual SASE FEL. When energy modulation of the electron beam becomes to be comparable with local energy spread, the electron bunch passes via dispersion section resulting in an effective compression of the electron bunch. Then bunched electron beam enters the second half of the undulator where the gap is tapered for effective extraction of the energy from the electron bunch. Our studies shows that output radiation power can reach a sub-TW level in Angstrom wavelength range.