Comprehensive study on plasma waves in the magnetosphere

磁层等离子体波的综合研究

基本信息

批准号：
10044081
负责人：
MATSUMOTO Hiroshi
金额：
$ 9.66万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10044081/
关键词：
Geotail Polar Wind Computer experiment Type III Solar Radio Burst Electrostatic Solitary Waves Kilometric continuum NEN POLAR WIND FAST AKEBONO ISTP 磁気圏

项目摘要

The main topics which we focused on in this project are categorized as follows : 1. Generation and propagation of electromagnetic waves, 2. Relation of plasma wave activities to geomagnetic activities, and 3. Generation of electrostatic waves. In the topic 1, one of waves we investigated is the Auroral Myriametirc Radiation (AMR), which was discovered by Geotail spacecraft. We conducted the numerical calculation using the ray tracing method and compared obtained results on the propagation charcteristics with observational results. Our research shows that the AMR is radiated around the same region of AKR(Auroral Kilometoric Radiation) in the polar atmosphere. In the second topic, we performed the collaboration between Geotail and Equator-S satellites. We observed the dynamic motion and time variation of the plasma sheet structure using these two satellites and revealed the thinning effect and dipolalization of the geomagnetic field line first time from the multiple-spacecraft observatio … More ns. Further, we also examined the Geotail data which were observed in the low latitude boundary region and obtained that there exist different mechanisms which cause the plasma transportation from the magnetosheath into the magnetosphere. In the topic 3, we conducted the statistical analyses on the Electrostatic Solitary Waves (ESW), which are observed in the Plasma Sheet Boundary Layer (PSBL). The results are very consistent with the expected features of ESW by computer simulations. This agreement supports the model that the nonlinear evolution of electron beam instabilities lead to the formation of isolated electrostatic potential structures, which are proposed by computer simulations. We also examined the correlation between the NEN activities(Narrowband Electrostatic Noise)and electrons. We found the close relation between NEN activities and the existence of polar electrons. The structure of polar electron velocity distributions lead to destabilize the electron velocity space hole mode, which was proposed as the generation mechanism of NEN. Less

我们在该项目中关注的主要主题分类如下：1。电磁波的产生和传播，2。等离子体波活性与地磁活动的关系，以及3。静电波的产生。在该主题1中，我们研究的波浪之一是岩土航天器发现的极光米里特里克辐射（AMR）。我们使用射线示踪方法进行了数值计算，并将繁殖炭化的结果与观察结果进行了比较。我们的研究表明，AMR在极地气氛中围绕同一AKR区域（极光层辐射）辐射。在第二个主题中，我们进行了Geotail和Equator-S卫星之间的合作。我们使用这两个卫星观察了等离子板结构的动态运动和时间变化，并揭示了第一次从多间谍科克克罗夫观察者（More Ns）开始的地磁场线的稀疏效果和偶极性。此外，我们还检查了在低纬度边界区域中观察到的地形尾数据，并获得了存在不同的机制，这些机制导致血浆从磁层转移到磁层中。在主题3中，我们对静电孤立波（ESW）进行了统计分析，该分析在浆片边界层（PSBL）中观察到。结果与计算机模拟的ESW的预期功能非常一致。该协议支持以下模型，即电子束不稳定性的非线性演变导致形成孤立的静电电位结构，该结构是由计算机模拟提出的。我们还检查了NEN活动（窄带静电噪声）和电子之间的相关性。我们发现NEN活动与极性电子的存在之间的密切关系。极性电子速度分布的结构导致不稳定电子速度空间孔模式，该模式被认为是NEN的发电机理。较少的