title: Optimization of a seeded free-electron laser with helical undulators.
abstract: Seeded single pass free-electron lasers are promising coherent, short-duration, and intense light sources, from the visible to x rays. Operated with adjustable undulators, they are also a unique device for providing fully variable polarized radiation. We report here the first seeding of helical undulators with a variable polarized source. We demonstrate that the adjustment of the seed polarization and focusing allows the free-electron laser radiation to be optimized in terms of intensity and quality.
authors.affiliation: Centre CEA-Saclay, DSM/DRECAM/SPAM, 91 191 Gif-sur-Yvette, France. marie.labat@synchrotron-soleil.fr
authors.forename: M
authors.initials: M
authors.lastname: Labat
authors.forename: M
authors.initials: M
authors.lastname: Hosaka
authors.forename: M
authors.initials: M
authors.lastname: Shimada
authors.forename: M
authors.initials: M
authors.lastname: Katoh
authors.forename: M E
authors.initials: ME
authors.lastname: Couprie