2005 Fiscal Year Final Research Report Summary
Experimental Investigation of Lower-Hybrid Solitons Using a Large-Volume, High-Density Helicon-Plasma Source
Project/Area Number |
15340199
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Research Category |
Grant-in-Aid for Scientific Research (B)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Plasma science
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Research Institution | Tokai University |
Principal Investigator |
TANIKAWA Takao Tokai University, Research Institute of Science and Technology, Professor, 総合科学技術研究所, 教授 (70207174)
|
Co-Investigator(Kenkyū-buntansha) |
SHINOHARA Shunjiro Kyusyu University, Interdisciplinary Graduate School of Engineering Sciences, Associate Professor, 大学院・総合理工学研究院, 助教授 (10134446)
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Project Period (FY) |
2003 – 2005
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Keywords | Lower-Hybrid Waves / Solitons / Cavitons / Helicon-Plasma Source / Nonlinear Plasma Waves / Plasma Wave Phenomena / Space Plasmas / Ion Acceleration |
Research Abstract |
1. A large volume helicon-plasma device (74 cm in diameter, 486 cm in length, and B_<max> = 2 kG) has been developed at ISAS/JAXA (the Institute of Space and Astronautical Science, a division of the Japan Aerospace Exploration Agency). With the use of a large flat-spiral antenna (43 cm in diameter, 4 turns), the device is capable of producing a world-largest-volume helicon-plasma of n_e 【greater than or equal】 10^<12> cm^<-3> with moderate rf input power of 〜500 W for Ar (【less than or equal】2 kW for He). 2. With this device, it is possible to control the radial density profile by (1) changing the magnetic-field configuration near the antenna and (2) changing the antenna radiation-field patterns. 3. Another helicon-plasma device (20 cm in diameter, 100 cm in length, and B_<max> = 0.6 kG), which is specialized to excite large amplitude lower-hybrid waves, has been developed at Tokai University. The device utilizes a specially designed segmented multi-loop antenna for both plasma production and wave excitation. 4. At ISAS/JAXA, it was attempted to excite lower-hybrid (LH) cavity modes inside a pre-produced low density channel along the axis by using an axially long grid-antenna. The excitation of cavity eigen-modes has not been confirmed yet. 5. At Tokai, a series of experiments has been initiated in order to excite LH solitons using an outer part of the multi-loop antenna as an exciter. 6. In the future experiment, it will be attempted to observe cross-field acceleration of plasma ions due to localized fields associated with LH solitons.
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Research Products
(64 results)