Experiments on the Stability and Equilibrium of Nonneutral Plasmas in Ultra High Magnetie Field

超高磁场中非中性等离子体的稳定性与平衡实验

• 批准号: 08458107
• 负责人: MOHRI Akihiro
• 金额: $ 4.03万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08458107/
• 关键词: nonneutral plasma; electrostatic wave; confinement; diocotron oscillation; image charge; dispersion relation; equilbrium condition; サイクロトロン放射冷却; 陽電子プラズマ; 電子プラズマ; 非線形波動; 平衡安定性; 超電導コイル

This project obtained the following results through experiments using developed Muti-Ring-Electrode (MRE) traps which produce confinement field configuration like Penning trap ;1.The confinement of plasma is much improved when the electrostatic potential of the MRE is set to compensate the image charge effects. In the high magnetic field the time reached to 104 sec.2.Nonlinear transition among electrostatic oscillation modes was observed. The threshold of the transition and the appearance of sideband waves were present in this transition.3.It was experimentally shown that diocotron oscillations in an electron plasma is suppressed by exciting axisymmetric electrostatic waves.4.The dispersion relation of a spheroidal plasma approaches to that of Dubin1s theory as the aspect ratio becomes smaller, whereas, for larger aspect ratio, the relation tends to the dispersion relation given for a long cylindrical column plasma.5.Observed dependence of electrostatic mode frequency of a spheroidal electron plasma is easily estimated by including the second temperature-dependent term in the dielectric tensor.

本项目通过使用改进的多环电极(MRE)陷阱进行实验，得到了以下结果：1.通过设置MRE的静电势来补偿镜像电荷效应，可以大大改善等离子体的约束程度。在强磁场下，时间可达104秒。2.观察到了静电振荡模式之间的非线性转变。3.实验表明，激发轴对称静电波可以抑制电子等离子体中的二极管振荡。4.随着长径比的减小，球形等离子体的色散关系更接近于Dubin1理论的色散关系，而对于较大的长径比，色散关系则趋向于给出的长圆柱形等离子体的色散关系。5.通过在介电张量中包含第二个温度相关项，可以很容易地估计出球形电子等离子体的静电模频率的观测依赖关系。

项目成果

Y.Yamazawa, T.Michishita and A.Mohri: "Damping of Diocotron Oscillation in a Nonneutral Electon Plasma by Excited Axisymmetric Electrostatic Wave" Jpn.J.Appl.Phys.36-12A. L1612-L1615 (1997)

Y.Yamazawa、T.Michishita 和 A.Mohri：“激发轴对称静电波对非中性电子等离子体中双波管振荡的阻尼”Jpn.J.Appl.Phys.36-12A。

H.Higaki, A.Mohri: "Experiment on diocotron oscillations of spheroidal nonneutral electron plasmas in the multi-ring electrode trap" Physics Letters. A235. 504-507 (1997)

H.Higaki、A.Mohri：“多环电极陷阱中球状非中性电子等离子体的双波管振荡实验”《物理快报》。

A.Mohri, H.Higaki, H.Tanaka, Y.Yamazawa, M.Aoyagi, T.Yuyama and T.Michishita: "Confinement of Nonneutral Spheroidal Plasmas in Multi-Ring-Electrode Traps" Jpn.J.Appl.Phys.37-2. 664-670 (1998)

A.Mohri、H.Higaki、H.Tanaka、Y.Yamazawa、M.Aoyagi、T.Yuyama 和 T.Michishita：“多环电极陷阱中非中性球状等离子体的限制”Jpn.J.Appl.Phys。

H.Higaki, A.Mohri: "Wall and Temperature Effects on Electrostatic Oscillations of Spheroidal Non-neutral Electron Plasmas in the Multi-Ring Electrode Traps" Japanese Journal of Applied Physics. 36・8. 5300-5305 (1997)

H.Higaki，A.Mohri：“多环电极陷阱中球状非中性电子等离子体静电振荡的壁和温度效应”日本应用物理学杂志 36・8（1997）。

H.Higaki, A.Mohri: "Wall and Temperature Effects on Electrostatic Oscillations of Spheroidal Non-neutral Electron Plasmers in the Multi-Ring Electrode Traps" Japanese Journal of Applied Physics. 36・8. 5300-5305 (1997)

H.Higaki，A.Mohri：“多环电极陷阱中球状非中性电子等离子体的静电振荡的壁和温度效应”日本应用物理学杂志 36・8（1997）。