title: Correlation between double and nonresonant single ionization.
abstract: We performed simultaneous measurements of electrons and ions produced in Xe photoionization driven by an 800-nm, 100-fs laser pulse. The obtained energy and angular resolved electron spectra allow the identification of the electronic states populated during the ionization. Xe2+ ions appear at the same laser intensity as electrons emerging from a nonresonant 9-photon ionization process of Xe. Similar to optical tunneling ionization, the nonresonant ionization delivers low-energy electrons needed for the formation of Xe2+ by a backscattering process.
authors.affiliation: Department of Molecular and Optical Physics, Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Strasse 3, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Wiehle
authors.forename: B
authors.initials: B
authors.lastname: Witzel