Collaborative Research: Remote Sensing of Electron Density Using Auroral Radio Emissions

这个项目将研究无线电波在磁层与电离层的电磁耦合中的作用。特别地，它将检查极光的嘶嘶声和中频爆发（MFB），它们出现在极光区，是对磁暴发生的迅速反应。除了与亚暴的发生有关外，极光射电发射还与许多其他极光现象有关，如极移弧和无线电波吸收的增加。该项目将采用实验测量与理论和数值分析相结合的方法。该项目的一个重要组成部分将是测量MFB事件的全波形和精细结构。波形测量将在多个地点和多个事件中进行。在某些情况下，可以使用非相干散射雷达数据来确定电离层内影响波传播和色散的等离子体密度结构。MFB事件的统计分析，结合共轭卫星测量，将用于确定与事件相关的电子沉淀的性质。理论和数值分析将决定Langmuir波和z模波是否可以解释中频爆发产生所需的模式转换过程。磁层-电离层耦合和磁亚暴已被确定为我们了解近地空间等离子体的中心问题。本项目将研究极光嘶嘶声和中频波爆发在M-I耦合中的作用。研究生和本科生将参与该项目的各个方面的研究，包括波测量仪器的开发、仪器的部署、仪器数据的分析以及相关的等离子体理论。大部分研究将在达特茅斯学院进行，并将通过达特茅斯女性科学项目（WISP）为一年级和二年级的女性提供参与研究的机会。

This project will investigate the role of radio waves in the electromagnetic coupling of the magnetosphere to the ionosphere. In particular it will examine auroral hiss and medium frequency bursts (MFB), which appear in the auroral zones as a prompt response to the onset of a magnetic substorm. In addition to the association with substorm onset, auroral radio emissions are associated with a number of other auroral phenomena, such as poleward-moving arcs and increases in radio wave absorption. The project will use a combination of experimental measurement and theoretical and numerical analysis. An important part of the project will be the measurement of full waveforms and fine structure in MFB events. The waveform measurements will be performed at multiple sites and for multiple events. In some cases it will be possible to use incoherent scatter radar data to determine the plasma density structures within the ionosphere that affect the propagation and dispersion of the waves. Statistical analysis of MFB events, in conjunction with conjugate satellite measurements, will be used to determine the nature of electron precipitation associated with the events. The theoretical and numerical analyses will determine whether or not Langmuir and Z-mode waves can explain the mode conversion processes need to explain the generation of medium frequency bursts.Magnetosphere-ionosphere coupling and magnetic substorms have been identified as central problems to our understanding of near-earth space plasmas. This project will examine the role that auroral hiss and medium frequency wave bursts play in M-I coupling. Both graduate and undergraduate students will participate in this project in all aspects of the research, including the development of wave measurement instruments, the deployment of the instruments, the analysis of the data obtained from the instruments and the related plasma theory. The majority of the research will take place at Dartmouth College and will offer opportunities for first and second year women to participate in the research through the Dartmouth Women-in-Science Program (WISP).