1993 Fiscal Year Final Research Report Summary
Formation of the double layr in tow temperature plasma
| Project/Area Number |
04680017
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
プラズマ理工学
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| Research Institution | Tokai University |
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Principal Investigator |
KAWAMURA Kazutaka INSTITUTE OF RESEARCH & DEVELOPMENT, TOKAI UNIVERSITY, PROFESSED, 開発技術研究所, 教授 (80016865)
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| Co-Investigator(Kenkyū-buntansha) |
TONEGAWA Akira DEPARTMENT OF PHYSICS, SCHOOL OF SCIENCE, TOKAI UNIVERSITY, LECTURER, 理学部・物理学科, 講師 (90197905)
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| Project Period (FY) |
1992 – 1993
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| Keywords | CURRENT FREE DOUBLE LAYER / TWO-TEMPERATURE-PLASMA / LaB_6HOLLOW CATHODE / POTENTIAL FORMATION / ELECTRON DISTRIBUTION / EMISSIVE PROBE / CATHODE SHEATH |
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| Research Abstract |
A current-free double layr near the cathode wall has been experimentally investigated in a two-electron-temperature plasma by using a LaB_6 hollow cathode tube. This LaB_6 hollow cathode tube allows us to have stable discharge with two-electron-temperature plasma in the glow-arc transition during which the discharge characteristics change from the glow to the arc. In the glow-arc transition, the interactions of beam electrons is very strong because of the high-voltage discharge and the thermionic electron emission effect. The electron distribution composed of two Maxwellians at different temperatures is observed in the LaB_6 hollow cathode tube. The electron population at this tube consists of a cold, high-density Maxwellian and a hot, low-density Maxwellian. The ratio of n_h to n_c is controlled by varying the argon neutral gas pressure while maintaining a constant discharge current (I_d = 1.0 A). As the gas pressure is decreased, n_h/n_c increases in the LaB_6 hollow cathode tube. At the same time, the current-free double layr are localized electrostatic potential structure created at the distance from the cathode wall of 5 mm.
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