Comparison of H sup minus and D sup minus production in a magnetically filtered multicusp source

Conference · Mon Jan 01 04:00:00 EST 1990 · Review of Scientific Instruments; (USA)

OSTI ID:6993002

Inoue, T; Ackerman, G D; Cooper, W S; Hanada, M; Kwan, J W; Ohara, Y; Okumura, Y; Seki, M ^[1]

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1. Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki-ken 311-01, Japan (JP)

A JAERI (Japan Atomic Energy Research Institute)negative ion source was tested at LBL (Lawrence Berkeley Laboratory) as part of the U.S.--Japan Fusion Cooperation Program. By varying the strength of the magnetic filter from 450 to 930 G cm, we compared production, transport, and extraction of the negative ions. The maximum current densities, which were obtained at the corresponding optimum filter strength for each gas species, were 10.4 mA/cm{sup 2} for H{sup {minus}} and 8.4 mA/cm{sup 2} for D{sup {minus}} at arc discharges of 40 kW. The ratio of the ion current densities ({ital J}{sub D{sup {minus}}}/{ital J}{sub H{sup {minus}}}) is about 0.8, which is higher than 1/(2){sup 1/2} . The electron to negative ion ratio was 13 for hydrogen and 38 for deuterium at the corresponding optimum filter strength. The higher ratio in deuterium is probably due to higher space potential of deuterium plasma by a few volts.

• OSTI ID: 6993002
• Report Number(s): CONF-890703--
• Conference Information: Journal Name: Review of Scientific Instruments; (USA) Journal Volume: 61:1
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700101* -- Fusion Energy-- Plasma Research-- Confinement
Heating
& Production
BEAM CURRENTS
BEAM EMITTANCE
BEAM EXTRACTION
BEAM PRODUCTION
BEAM TRANSPORT
CHARGED PARTICLES
CURRENTS
DEUTERIUM IONS
FILTERS
HYDROGEN IONS
ION SOURCES
IONS
MAGNETIC FILTERS
TESTING