CAREER: Exploring Mysterious Whistler Mode Waves in Earth's Plasmaspheric Plumes

该项目研究了被称为哨声模式波的极低频无线电波如何影响地球辐射带的动态。闪电产生哨声波，沿着沿着地球磁场线传播。了解这些波以及它们是如何被放大的，对国家安全和商业利益至关重要。军事和商业通信使用相同的甚低频无线电波长，因此会受到哨声波的干扰。由此产生的科学成果将有助于改进空间气象预测模型。这直接符合2015年发布的《国家空间气象战略和行动计划》的目标。该项目支持一名女教员，并将在研究和外联活动方面对研究生和本科生进行培训和教育。拟议的外展计划将针对K-12学生，通过开发互动式课堂演示，动手活动，以及BU天文台和天文馆的图尔斯之旅。外联活动将吸引本科生和研究生参与研究和向公众传播空间科学。等离子体层羽流中的哨声波表现出出乎意料的大振幅，表明该区域的波在驱动高能电子沉淀方面非常有效。目前，辐射带模型没有考虑到这种影响。为了理解哨声波在等离子体层羽流中对辐射带动力学的作用，该奖项将结合联合收割机理论，建模和数据分析。准线性扩散理论将被用来评估由于波粒相互作用的电子散射。这将与全扩散代码的建模相结合，以计算电子扩散系数和三维扩散代码，以模拟辐射带电子动力学。对多个航天器（包括货车艾伦探测器、THEMIS、POES/MetOp和GPS）的观测结果进行分析，将确定与等离子体层羽流中哨声波生成相关的密度、波和粒子特性。这些数据将与开发的模型进行比较，以回答科学问题。这项研究的独特之处在于它关注的是羽流中产生的哨声波，这是一个以前没有调查过的区域。该奖项反映了NSF的法定使命，并被认为值得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来支持。

This project investigates how very low frequency radio waves, known as whistler mode waves, affect the Earth's Radiation Belt dynamics. Lightning produces whistler waves, which travel along the Earth's magnetic field lines. Understanding these waves and how they are amplified is important to national security and commercial interests. Military and commercial communications utilize the same very low frequency radio wavelengths and are therefore disrupted by whistler waves. The resulting scientific results will lead to improvement of predictive space weather models. This fits directly into the goals of the National Space Weather Strategy and Action Plan, released in 2015. The project supports a female faculty member and will train and educate graduate and undergraduate students in both research and outreach activities. The proposed outreach program will target K-12 students through development of interactive in-class presentations, hands-on activities, and tours of the BU observatory and planetarium. The outreach will engage undergraduate and graduate students in both research and communicating space science to the public.Whistler mode waves in plasmaspheric plumes exhibit unexpectedly large amplitudes that suggest that waves in this region are very effective in driving energetic electron precipitation. Currently, radiation belt models do not incorporate this effect. In order to understand the role whistler waves in plasmaspheric plumes play on radiation belt dynamics, this award will combine theory, modeling, and data analysis. Quasilinear diffusion theory will be used to evaluate electron scattering due to wave-particle interactions. This will be combined with modeling from a Full Diffusion code to calculate electron diffusion coefficients and a 3D diffusion code to simulate radiation belt electron dynamics. Analysis of observations from multiple spacecraft, including the Van Allen Probes, THEMIS, POES/MetOp, and GPS, will establish density, wave, and particle properties associated with the generation of whistler waves in plasmaspheric plumes. The data will be compared to the developed model to answer the science questions. The study is unique in that it focuses on whistler waves generated in plumes, a region not previously investigated.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.