title: Emission of thermally activated electrons from rare gas clusters irradiated with intense VUV light pulses from a free electron laser.
abstract: The ionization dynamics of Ar and Xe clusters irradiated with intense vacuum ultraviolet light from a free-electron laser is investigated using photoelectron spectroscopy. Clusters comprising between 70 and 900 atoms were irradiated with femtosecond pulses at 95 nm wavelength (approximately 13 eV photon energy) and a peak intensity of approximately 4 x 10(12) W/cm2. A broad thermal distribution of emitted electrons from clusters with a maximum kinetic energy up to 30-40 eV is observed. The observation of relatively low-energy photoelectrons is in good agreement with calculations using a time-dependent Thomas-Fermi model and gives experimental evidence of an outer ionization process of the clusters, due to delayed thermoelectronic emission.
authors.affiliation: Max-Born-Institute, Max-Born Strasse 2a, D-12489 Berlin, Germany. laarmann@mbi-berlin.de
authors.forename: T
authors.initials: T
authors.lastname: Laarmann
authors.forename: M
authors.initials: M
authors.lastname: Rusek
authors.forename: H
authors.initials: H
authors.lastname: Wabnitz
authors.forename: J
authors.initials: J
authors.lastname: Schulz
authors.forename: A R B
authors.initials: AR
authors.lastname: de Castro
authors.forename: P
authors.initials: P
authors.lastname: Gürtler
authors.forename: W
authors.initials: W
authors.lastname: Laasch
authors.forename: T
authors.initials: T
authors.lastname: Möller