title: Spatially localized self-injection of electrons in a self-modulated laser-wakefield accelerator by using a laser-induced transient density ramp.
abstract: By using a laser-induced transient density ramp, we demonstrate self-injection of electrons in a self-modulated laser-wakefield accelerator with spatial localization. The number of injected electrons reaches 1.7 x 10(8). The transient density ramp is produced by a prepulse propagating transversely to drill a density depression channel via ionization and expansion. The same mechanism of injection with comparable efficiency is also demonstrated with a transverse plasma waveguide driven by Coulomb explosion.
authors.affiliation: Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan.
authors.forename: T-Y
authors.initials: TY
authors.lastname: Chien
authors.forename: C-L
authors.initials: CL
authors.lastname: Chang
authors.forename: C-H
authors.initials: CH
authors.lastname: Lee
authors.forename: J-Y
authors.initials: JY
authors.lastname: Lin
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: S-Y
authors.initials: SY
authors.lastname: Chen