In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 35, No. 4R ( 1996-04-01), p. 2356-
Abstract:
A large rf-driven negative hydrogen ion source has been developed for a neutral beam injection (NBI) system in future experimental fusion devices. Dimensions of the rf plasma generator are 30×30×20 cm 3 . An induction coil antenna is fully immersed into the plasma generator. The rf-driven plasma with an electron density of 1.5×10 12 cm -3 was generated at 28 kW rf power at a frequency of 2 MHz. The electron temperature in the extraction region decreases as the line-integrated magnetic filter field strength increases. An electron temperature in the extraction region of 1 eV, which is suitable for generating negative ions, was obtained at a line-integrated filter field strength of 1030 G cm. Negative hydrogen ions are extracted from a single aperture of 13 mm in diameter in a pure-volume operation. An extracted negative ion current of 5.5 mA was obtained at 13.1 mTorr gas pressure and 15 kW rf power. This negativeion current corresponds to a power efficiency of 5.0 ( mA/cm 2 )/( W/cm 3 ), which is superior to that in filament-arc negative ion sources.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.35.2356
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
1996
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7
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