title: Recoil-Ion momentum distributions for single and double ionization of helium in strong laser fields
abstract: We have measured the momentum distributions of singly and doubly charged helium ions created in the focus of 220 fs, 800 nm laser pulses at intensities of (2.9-6.6)x10(14) W/cm(2). All ions are emitted strongly aligned along the direction of polarization of the light. We find the typical momenta of the He2+ ions to be 5-10 times larger than those of the He1+ ions and a two peak structure at the highest intensity.
authors.affiliation: Institut fur Kernphysik, Universitat Frankfurt, D-60486 Frankfurt, Germany.
authors.initials: T
authors.lastname: Weber
authors.initials: M
authors.lastname: Weckenbrock
authors.initials: A
authors.lastname: Staudte
authors.initials: L
authors.lastname: Spielberger
authors.initials: O
authors.lastname: Jagutzki
authors.initials: V
authors.lastname: Mergel
authors.initials: F
authors.lastname: Afaneh
authors.initials: G
authors.lastname: Urbasch
authors.initials: M
authors.lastname: Vollmer
authors.initials: H
authors.lastname: Giessen
authors.initials: R
authors.lastname: Dorner