Extreme ultraviolet ionization of pure He nanodroplets: Mass-correlated photoelectron imaging, Penning ionization, and electron energy-loss spectra

Journal Article · Wed Aug 28 00:00:00 EDT 2013 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4818531· OSTI ID:22224158

Buchta, D.; Stienkemeier, F.; Mudrich, M. ^[1]; Krishnan, S. R.; Moshammer, R. ^[2]; Brauer, N. B.; Drabbels, M. ^[3]; O’Keeffe, P.; Coreno, M. ^[4]; Devetta, M. ^[5]; Di Fraia, M. ^[6]; Callegari, C.; Richter, R.; Prince, K. C. ^[7]; Ullrich, J. ^[2]

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1. Physikalisches Institut, Universität Freiburg, 79104 Freiburg (Germany)
2. Max-Planck-Institut für Kernphysik, 69117 Heidelberg (Germany)
3. Laboratoire de Chimie Physique Moléculaire, Swiss Federal Institute of Technology Lausanne (EPFL), 1015 Lausanne (Switzerland)
4. CNR Istituto di Metodologie Inorganiche e dei Plasmi, CP10, 00016 Monterotondo Scalo (Italy)
5. CIMAINA and Dipartimento di Fisica, Università di Milano, 20133 Milano (Italy)
6. Department of Physics, University of Trieste, 34128 Trieste (Italy)
7. Elettra-Sincrotrone Trieste, 34149 Basovizza, Trieste (Italy)

The ionization dynamics of pure He nanodroplets irradiated by Extreme ultraviolet radiation is studied using Velocity-Map Imaging PhotoElectron-PhotoIon COincidence spectroscopy. We present photoelectron energy spectra and angular distributions measured in coincidence with the most abundant ions He{sup +}, He{sub 2}{sup +}, and He{sub 3}{sup +}. Surprisingly, below the autoionization threshold of He droplets, we find indications for multiple excitation and subsequent ionization of the droplets by a Penning-like process. At high photon energies we observe inelastic collisions of photoelectrons with the surrounding He atoms in the droplets.

• OSTI ID: 22224158
• Journal Information: Journal of Chemical Physics, Vol. 139, Issue 8; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANGULAR DISTRIBUTION
AUTOIONIZATION
DROPLETS
ENERGY SPECTRA
ENERGY-LOSS SPECTROSCOPY
EXTREME ULTRAVIOLET RADIATION
HELIUM IONS
IRRADIATION
PHOTOELECTRON SPECTROSCOPY
PHOTOIONIZATION
PHOTON-ATOM COLLISIONS