Development of Models of Electron Density in the Magnetosphere from Ground and Satellite-Based Radio Data

这笔赠款的目的是开发和解释地球磁层赤道平面内电子密度的经验模型。一旦可用，这些模型将为研究磁层对流、波-粒子相互作用以及磁层和电离层之间的等离子体交换提供一个显著改进的基础。这些模型将主要基于斯坦福大学在南极站记录的哨声和爱荷华大学等离子体波实验扫描频率接收器在ISEE-1卫星上的结果。磁层研究日益重视发展等离子体分布和动力学的理论和经验模型，这方面的一个例子是1986年10月举行的关于磁层-电离层等离子体模型的亨茨维尔讲习班。在人们可以用经验建立模型的磁层等离子体参数中，赤道电子密度NEQ现在似乎是最重要和最容易获得的参数之一。这个参数具有科学价值，原因有很多。它取决于一些难以观测的基本物理过程，例如太阳风引起的对流和相关的亚暴形态，以及电离与时空可变的电离层的互换。NEQ代表赤道传播介质，因此是关于波折射率的条件，在该条件下发生共振波粒子相互作用，包括来自辐射带的粒子散射。赤道等离子体也是介质的重要组成部分，超低频波必须通过它从太阳风或磁层顶区携带能量传播，在那里波粒相互作用可以在超低频下被调制。

The purpose of this grant is for the development and interpretation of empirical models of electron density in the equatorial plane of the earth's magnetosphere. When available, these models will provide a substantially improved basis for studies of magnetospheric convection, wave-particle interactions, and plasma interchange between the magnetosphere and ionosphere. The models would be based primarily upon a combination of results from whistlers recorded be Stanford University at Antarctic stations and from the University of Iowa Plasma Wave Experiment Sweep Frequency Receiver on the ISEE-1 satellite. Magnetospheric research has reached a point of increasing emphasis upon the development of theoretical and empirical models of the plasma distribution and dynamics, an example of this emphasis being the October 1986 Huntsville Workshop on Magnetosphere-Ionosphere Plasma Models. Among the magnetospheric plasma parameters which one can model empirically, equatorial electron density neq now appears to be one of the most important and most accessible. This parameter is of scientific interest for many reasons. It depends upon a number of fundamental physical processes that are difficult to observe, such as solar wind induced convection and relate substorm morphology and the interchange of ionization with the spatially and temporally variable ionosphere. neq represents the equatorial propagation medium and hence the conditions on wave refractive index under which resonant wave particle interactions take place, including particle scattering from the radiation belts. The equatorial plasma is also an important part of the medium through which ULF waves must propagate in carrying energy form either the solar wind or the magnetopause regions where wave-particle interactions may be modulated at ULF frequencies.