Project/Area Number |
04680017
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
プラズマ理工学
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Research Institution | Tokai University |
Principal Investigator |
KAWAMURA Kazutaka INSTITUTE OF RESEARCH & DEVELOPMENT, TOKAI UNIVERSITY, PROFESSED, 開発技術研究所, 教授 (80016865)
|
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)
高山 一男 東海大学, 開発技術研究所, 教授 (20023690)
|
Project Period (FY) |
1992 – 1993
|
Project Status |
Completed (Fiscal Year 1993)
|
Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1993: ¥400,000 (Direct Cost: ¥400,000)
Fiscal Year 1992: ¥1,600,000 (Direct Cost: ¥1,600,000)
|
Keywords | CURRENT FREE DOUBLE LAYER / TWO-TEMPERATURE-PLASMA / LaB_6HOLLOW CATHODE / POTENTIAL FORMATION / ELECTRON DISTRIBUTION / EMISSIVE PROBE / CATHODE SHEATH / ダブルレイヤー / ホロー陰極 / 高速電子 / LaB_6 / グロー・アーク / 遷移領域 |
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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