title: Pulse splitting in short wavelength seeded free electron lasers.
abstract: We investigate a fundamental limitation occurring in vacuum ultraviolet and extreme ultraviolet seeded free electron lasers (FELs). For a given electron beam and undulator configuration, an increase of the FEL output energy at saturation can be obtained via an increase of the seed pulse duration. We put in evidence a complex spatiotemporal deformation of the amplified pulse, leading ultimately to a pulse splitting effect. Numerical studies of the Colson-Bonifacio FEL equations reveal that slippage length and seed laser pulse wings are core ingredients of the dynamics.
authors.affiliation: Synchrotron SOLEIL, Saint Aubin, BP 34, 91 192 Gif-sur-Yvette, France. marie.labat@synchrotron-soleil.fr
authors.forename: M
authors.initials: M
authors.lastname: Labat
authors.forename: N
authors.initials: N
authors.lastname: Joly
authors.forename: S
authors.initials: S
authors.lastname: Bielawski
authors.forename: C
authors.initials: C
authors.lastname: Szwaj
authors.forename: C
authors.initials: C
authors.lastname: Bruni
authors.forename: M E
authors.initials: ME
authors.lastname: Couprie