title: Electron pair emission from a W(001) surface: photon versus electron excitation.
abstract: The electron pair emission from a W(001) surface was studied using a coincidence time-of-flight spectrometer. The aim of this study was to compare the pair emission upon electron impact and upon photon absorption. The energy distributions are markedly different for these two experiments. From this we conclude that the photon-stimulated pair emission carries a significant contribution from a double photoemission process, while the process of first creating a photoelectron, which in a subsequent collision leads to pair emission, is of less importance.
authors.affiliation: Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Muñoz-Navia
authors.forename: C
authors.initials: C
authors.lastname: Winkler
authors.forename: R
authors.initials: R
authors.lastname: Patel
authors.forename: M
authors.initials: M
authors.lastname: Birke
authors.forename: F O
authors.initials: FO
authors.lastname: Schumann
authors.forename: J
authors.initials: J
authors.lastname: Kirschner