Theoretical and Experimental Studies of Auroral Farley-Buneman Waves

在部分电离等离子体中，当电子相对于离子的跨场漂移超过临界阈值时，会触发Farley-Buneman（FB）波不稳定性。这种现象大大改变了电流，从而影响整个磁层-电离层（MI）系统的响应，主要是在风暴期间。FB波也会产生很强的雷达回波，这些回波可以用来监测MI系统。FB波的原始理论是基于线性的局部流体理论，该理论不考虑波的许多观测方面。工作的结果将提高MI耦合的理解，不仅通过修改这种耦合的模型，而且通过诊断使用FB波产生的雷达回波。该项目将资助一名研究生，并让硕士和本科生参与空间研究。主要研究人员（PI）将综合改进的理论，非线性数值模拟和许多不同的观测结果，包括高频主动极光研究计划（HAARP）加热器的测量结果。该项目将实施一种新的方法，雷达成像使用“压缩传感。“这项技术已经在其他领域发生了变革，并被视为对大气区域耦合、能量学和动力学（CEDAR）无线电科学界有潜在的好处。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Farley-Buneman (FB) wave instability is triggered in a partially ionized plasma when a cross-field drift of electrons relative to ions exceeds a critical threshold value. This phenomenon substantially modifies current flows, and thus affects the response of the entire Magnetosphere-Ionosphere (MI) system, primarily during storm-time. FB waves also produce strong radar echoes, and these allow monitoring of the MI system. The original theory of FB waves is based on linear, local fluid theory that does not account for many observed aspects of the waves. The results of the work would improve understanding of MI coupling not only though the modification of models of this coupling, but also through the diagnostic use of the radar echoes produced by FB waves. The project will fund a graduate student and engage Master's and undergraduate students in space research.The Principal Investigators (PIs) will synthesize improved theory, nonlinear numerical simulation, and numerous disparate observations, including measurements from the High Frequency Active Auroral Research Program (HAARP) heater. The project will implement a new approach to radar imaging using "compressive sensing." This technique has been transformative in other fields, and is seen as potentially beneficial to the Coupling, Energetics and Dynamics of Atmospheric Regions (CEDAR) radio science community.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.