Laboratory Experiments on Electrostatic Potential Structure concerned with Aurora Phenomenon

与极光现象有关的静电势结构的室内实验

• 批准号: 61460226
• 负责人: SATO Noriyoshi
• 金额: $ 4.29万
• 依托单位: TOHOKU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1987
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-61460226/
• 关键词: AURORA; MAGNETIC MIRROR; 電位構造

It is quite important to understand aurora phenomena in order to clarify a dynamic feature of the Earth's madnetosphere. Electron acceleration inducing auroral discharge has been supposed to be due to a plasma potential slope along the magnetic field lines above the auroral ovalIn this work, measurements were performed on porenrial formation along the mahnetic field lines in a loboratory plasma. A collisionless plasma, produced by surface ionization of k atoms on a hot tungsten plate heated up to about 2300k, was confined by a strong axial magnetic field with mirror configuration. The plasma flow speed V was varied in the wide range of V_o/C_s(C_s: ion acoustic speed)The plasma potential is found to increase in the region where the magnetic field lines are converged, being consistent with theoretical prediction based on different pitch angles of electrons and ions. When the plasma front reaches the endplate, howevwe, a big effect of the end- plate is recognized, i.e., for a positive bias potential of the endplate, the plasma potential increase is drastically enhanced. Three-dimensional structure of the potential profile shows a large electric field across the magnetic field, being similar to that above the auroral oval.

了解极光现象对于阐明地球疯狂层的动态特征非常重要。引起极光放电的电子加速被认为是由于沿极光椭圆上方磁场线的等离子体电势斜率造成的。在这项工作中，对沿着实验室等离子体中的磁力线的孔洞形成进行了测量。无碰撞等离子体是由加热至约 2300k 的热钨板上 k 原子的表面电离产生的，受到具有镜面配置的强轴向磁场的限制。等离子体流速V在V_o/C_s（C_s：离子声速）的宽范围内变化，发现磁场线汇聚区域的等离子体电势增加，这与基于电子和离子不同螺距角的理论预测一致。然而，当等离子体前沿到达端板时，我们认识到端板的巨大影响，即，对于端板的正偏压电势，等离子体电势增加急剧增强。电势剖面的三维结构显示出穿过磁场的大电场，与极光椭圆形上方的电场类似。

项目成果

A.Tsushima: Physical Review Letters. 56. 1815-1818 (1986)

A.Tsushima：物理评论快报。

A. Komori: "Control of Plasma Fluctuations by Using Shaped Derromagnetic Material" Physical Review A. 34. 4453-4456 (1986)

A. Komori：“使用成形铁磁材料控制等离子体波动”物理评论 A. 34. 4453-4456 (1986)

A. Tsushima: "Physical Review Letters" Cotrol Radial Potential Profile and Nonambipolar Ion Transport in an Electron Resonance Mirror Plasma. 1815-1818 (1986)

A. Tsushima：“物理评论快报”控制电子共振镜等离子体中的径向电势分布和非双极离子传输。

N. Sato: "Three-Dimensional Double Layers Inducing Ion-Cyclotron Oscillations in a Collisionless Plasma" Physical Review Letters. 1227-1230 (1986)

N. Sato：“三维双层在无碰撞等离子体中诱导离子回旋振荡”物理评论快报。

A.Komori: Physical Review A. 34. 4453-4456 (1986)

A.小森：物理评论 A. 34. 4453-4456 (1986)