Charging of insulators by multiply-charged-ion impact probed by slowing down of fast binary-encounter electrons

Journal Article · Wed Dec 15 04:00:00 EST 2010 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.82.062901· OSTI ID:21528898

De Filippo, E; Lanzano, G; Cardella, G ^[1]; Amorini, F ^[2]; Geraci, E; Grassi, L; Politi, G ^[1]; La Guidara, E ^[1]; Lombardo, I; Rizzo, F ^[2]; Russotto, P ^[2]; Volant, C ^[3]; Hagmann, S ^[4]; Rothard, H ^[5]

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1. Istituto Nazionale di Fisica Nucleare Sezione di Catania, Via S. Sofia 64, I-95123 Catania (Italy)
2. Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali del Sud, LNS, Via S. Sofia 62, I-95123 Catania (Italy)
3. Departement Astrophysique, physique des Particules, physique Nucleaire et de l'Instrumentation Associee/Service de Physique Nucleaire, CEA/Saclay, F-91191 Gif-sur-Yvette (France)
4. GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany)
5. Centre de Recherche sur les Ions, les Materiaux et la Photonique, CIMAP-CIRIL-Ganil (CEA/CNRS/ENSICAEN/Universite de Caen-Basse Normandie), BP 5133, F-14070 Caen Cedex 05 (France)

The interaction of ion beams with insulators leads to charging-up phenomena, which at present are under investigation in connection with guiding phenomena in nanocapillaries with possible application in nanofocused beams. We studied the charging dynamics of insulating foil targets [Mylar, polypropylene (PP)] irradiated with swift ion beams (C, O, Ag, and Xe at 40, 23, 40, and 30 MeV/u, respectively) via the measurement of the slowing down of fast binary-encounter electrons. Also, sandwich targets (Mylar covered with a thin Au layer on both surfaces) and Mylar with Au on only one surface were used. Fast-electron spectra were measured by the time-of-flight method at the superconducting cyclotron of Laboratori Nazionali del Sud (LNS) Catania. The charge buildup leads to target-material-dependent potentials of the order of 6.0 kV for Mylar and 2.8 kV for PP. The sandwich targets, surprisingly, show the same behavior as the insulating targets, whereas a single Au layer on the electron and ion exit side strongly suppresses the charging phenomenon. The accumulated number of projectiles needed for charging up is inversely proportional to electronic energy loss. Thus, the charging up is directly related to emission of secondary electrons.

• OSTI ID: 21528898
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 6 Vol. 82; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ACCELERATORS
BEAMS
COATINGS
CYCLIC ACCELERATORS
CYCLOTRONS
ELECTRON EMISSION
ELECTRON SPECTRA
ELECTRONS
ELEMENTARY PARTICLES
ELEMENTS
EMISSION
ENERGY LOSSES
ESTERS
FERMIONS
FOILS
GOLD
INTERACTIONS
ION BEAMS
LEPTONS
LOSSES
MATERIALS
METALS
MYLAR
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
POLYESTERS
POLYMERS
POLYOLEFINS
POLYPROPYLENE
POTENTIALS
SLOWING-DOWN
SPECTRA
SUPERCONDUCTING CYCLOTRONS
SURFACES
SYNTHETIC MATERIALS
TIME-OF-FLIGHT METHOD
TRANSITION ELEMENTS