Influence of the electron cross-field diffusion in negative ion sources with the transverse magnetic field and the plasma-electrode bias

Journal Article · Mon Feb 15 04:00:00 EST 2010 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.3259165· OSTI ID:22053887

Kuppel, S; Matsushita, D; Hatayama, A ^[1]; Bacal, M ^[2]

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1. Graduate School of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522 (Japan)
2. Laboratoire de Physique des Plasmas, UMR 7648 du CNRS, Ecole Polytechnique, 91128 Palaiseau (France)

The physical mechanisms involved in the extraction of H{sup -} ions from the negative ion source are studied with a PIC 2D3V code. The effect of a weak magnetic field transverse to the extraction direction is taken into account, along with a variable bias voltage applied on the plasma electrode (PE). In addition to previous modeling works, the electron diffusion across the magnetic field is taken into account as a simple one-dimensional random-walk process. The results show that without PE bias, the value of the diffusion coefficient has a significant influence upon the value of the extracted H{sup -} current. However, the value of this coefficient does not affect qualitatively the mechanism leading to the peak of extracted H{sup -} ion current observed for an optimum value of the PE bias.

• OSTI ID: 22053887
• Journal Information: Review of Scientific Instruments, Journal Name: Review of Scientific Instruments Journal Issue: 2 Vol. 81; ISSN 0034-6748; ISSN RSINAK
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
BEAM CURRENTS
COMPUTERIZED SIMULATION
DIFFUSION
ELECTRIC POTENTIAL
ELECTRODES
ELECTRONS
EXTRACTION
GRAPH THEORY
HYDROGEN IONS 1 MINUS
ION SOURCES
MAGNETIC FIELDS
ONE-DIMENSIONAL CALCULATIONS
PLASMA