Optimizing the emission, propagation, and focusing of an intense electron beam

Journal Article · Thu May 14 00:00:00 EDT 2015 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4919832· OSTI ID:22410172

Pepitone, K., E-mail: [e-mail]; Gardelle, J., E-mail: [e-mail]; Modin, P., E-mail: [e-mail] ^[1]

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1. CEA/CESTA, 15 avenue des Sablières, CS 60001, 33116, Le Barp (France)

Intense electron beams can be used to study the dynamical response of materials under shocks in order to adjust the models developed for hydrodynamics simulations. We present in this paper a characterization of beams produced in a field emission diode coupled to the generator RKA at CEA/CESTA. Cherenkov emission, produced by the beam interacting in a fused silica disk, was observed by fast optical cameras to estimate beam homogeneity. GEANT4 simulations were performed to estimate the transfer function of the silica target and to optimize the anode foil. First, we chose the best cathode material available among the most common materials used in field emission systems. In addition, we found that by optimization of the anode thickness, we could improve the spatial homogeneity of the beam which is of prime importance for computing the interaction of the beam with materials. Next, we changed the beam fluence by increasing the beam current and by reducing the beam radius. Finally, we studied the propagation and focusing of the electron beam in low pressure gases and observed that we could use self-magnetic field focusing in order to increase beam fluence at the target location. The experimental results are in good agreement with PIC simulations.

• OSTI ID: 22410172
• Journal Information: Journal of Applied Physics, Vol. 117, Issue 18; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
43 PARTICLE ACCELERATORS
BEAM CURRENTS
BEAM PROFILES
BEAM TRANSPORT
CHERENKOV RADIATION
COMPUTERIZED SIMULATION
ELECTRON BEAMS
FIELD EMISSION
FOILS
G CODES
GASES
HYDRODYNAMICS
MAGNETIC FIELDS
OPTIMIZATION
SILICA
THICKNESS
TRANSFER FUNCTIONS