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; 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Aurora现象是非常重要的，以阐明地球Madnetosphere的动态特征。诱导极光放电的电子加速度被认为是由于沿着极光椭圆形上方的磁场线的等离子体电势斜率这项工作，因此在左骨血浆中沿MAHNETIC田间线进行了测量。由k原子在热钨板上的表面电离产生的无碰撞等离子体被加热到约2300k的热量，被带有镜面构型的强轴向磁场限制。血浆流速V在V_O/C_S（C_S：离子声速度）的较大范围内变化。在收敛磁场线的区域中，血浆势会增加，与基于电子和离子的不同音高的理论预测一致。当等离子体前部到达终板时，识别端板的很大效果，即，对于端板的正偏差，血浆电位的增加会大大增强。电势轮廓的三维结构显示了整个磁场上的大电场，与极光椭圆形上方相似。