Outstanding Questions on Auroral Radiation Fine Structure

这项提案是为了继续研究等离子体波和辐射，它们在控制地球磁层中带电粒子的传输、损失率和能量交换中起着关键作用。这些波也直接或远程感知空间等离子体的过程、结构和与太阳风等离子体流相互作用的边界。在南极南极站操作一个数字无线电接收机（100千赫-5兆赫）将回答有关上述无线电发射的精细结构的一些悬而未决的问题：最近发现的低频（LF）极光嘶嘶声和中频（MF）爆发的精细结构之间的关系是什么？在亚秒时间尺度上，低频极光嘶嘶声和中频极光爆发在时间和空间上是相关的还是反相关的？在150-750千赫的结构“类似AKR”的辐射，表面上类似于极光千米辐射（AKR），是否AKR传输到地面的证据？南极无线电数据与地球磁尾深层Geotail卫星的相应数据的初步比较表明，AKR与地面“类AKR”事件之间存在良好的相关性，如果得到证实，将支持以前被忽视的AKR模式转换和向下传播理论。提议的实验必须在南极进行，因为低频/中频无线电环境的关键部分由于人为电磁干扰而无法在北半球观测到。该提案将为达特茅斯学院的本科生和研究生提供教育和培训，形成博士论文的主要部分。它也将为多个本科实习提供基础。作为这项工作的一部分，达特茅斯学院的研究人员将参与公共宣传，包括公开演讲或访问学校。

This proposal is funded to continue study of plasma waves and radiation that play key roles in controlling the charged particle transport, loss rates, and energy exchange in the Earth's magnetosphere. These waves also directly or remotely sense space plasma processes, structures, and boundaries that interact with the solar wind plasma flow. Operating a digital radio receiver (100 KHz -5 MHz) at the South Pole station in the Antarctic will answer some outstanding questions regarding the fine structure of above radio emission: What is the relationship between the recently discovered fine structures of low frequency (LF) auroral hiss and middle-frequency (MF) burst: two types of radio emissions that occur together at the onset of the auroral substorm? Are the LF auroral hiss and auroral MF burst correlated or anti-correlated temporally and spatially on sub-second time scales? Are structured "AKR-like" emissions at 150-750 kHz, which superficially resemble the Auroral Kilometric Radiation (AKR), evidence of transmission of AKR to ground level? Preliminary comparisons between South Pole radio data and corresponding data from the Geotail satellite deep in the Earth's magnetotail suggest a good correlation between AKR and the ground-level "AKR-like" events, which if confirmed will support previously ignored theories of mode conversion and downward propagation of AKR. The proposed experiments must be performed in the Antarctic, because critical portions of the LF/MF radio environment are impossible to observe at Northern Hemisphere locations due to man-made electromagnetic interference. This proposal will provide education and training to both the undergraduate and graduate students at Dartmouth College, forming the major part of a PhD dissertation. It will also provide the basis for multiple undergraduate internships. Researchers at Dartmouth College will participate in public outreach as a part of this work, including public talks or visits to schools.