Collaborative Research: Multi-instrument Studies of Auroral Plasma Radiation

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。等离子体波和辐射在空间物理中起着关键作用，在某些情况下起着控制粒子输运、损失率或能量交换的重要作用，在其他情况下作为直接或遥感空间等离子体过程、结构或边界的关键手段。由于所有这些原因，了解等离子体波和辐射的发射和传播是空间物理学的重中之重。拟议的研究将集中于将南极的低频/中频/高频无线电接收机的数据与其他成像仪器（如全天相机和成像测速仪）和电磁波实验（如宽带VLF接收机、极低频接收机和极低频搜索线圈）相结合。虽然已知极光射电发射与极光亚暴有关，但本提案中概述的方法将确定亚暴的哪些特征可以通过其射电发射进行遥感。提出的方法将为极光高频暴（一种未知原因的重要无线电发射）的产生机制提供关键线索，并确定最近发现的低频极光嘶嘶离散特征与那些已知发生在低频极光嘶嘶的特征之间是否存在联系。第二种方法是在具有极光等离子体波具体经验的等离子体理论家的帮助下，使相关等离子体理论适应数据解释。通过模式转换Langmuir波的数值射线追踪计算和非圆柱形密度不规则情况下离散上混合波的数值计算等理论方法，可以利用南极3个0.1-5.0 MHz接收机的数据有效地测试波和波结构的产生机制。与此项目相关的实地考察和分析工作非常适合研究生的参与和研究训练。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). Plasma waves and radiation play key roles in space physics, in some cases playing an important role controlling particle transport, loss rates, or energy exchange, and in other cases serving as a key means of directly or remotely sensing space plasma processes, structures, or boundaries. For all these reasons, understanding emission and propagation of plasma waves and radiation is a top priority in space physics. The proposed research will focus on combining data from the South Pole's set of LF/MF/HF radio receivers with other imaging instruments such as the all-sky cameras and the imaging riometer and electromagnetic wave experiments such as the broadband VLF receiver, the ELF receiver, and the ULF search coils. While it is known that auroral radio emissions are associated with auroral substorms, the methods outlined in this proposal will determine which features of the substorm can be remotely sensed by their radio emissions. The proposed methodology will provide key clues to the generation mechanism of auroral MF-burst, a significant radio emission of unknown cause, and determine whether there is a connection between the recently discovered LF auroral hiss discrete features and those known to occur at VLF. A second proposed method is to adapt relevant plasma theory to the data interpretation, with the help of a plasma theorist with specific experience in auroral plasma waves. By employing theoretical methods such as numerical ray-tracing calculations of mode-converted Langmuir waves and numerical calculations of discrete upper hybrid waves in the presence of non-cylindrical density irregularities, data from the three South Pole 0.1-5.0 MHz receivers can be used to effectively test generation mechanisms of the waves and wave structures. The fieldwork and analysis efforts associated with this project are highly suitable for involvement and research training of graduate students.