ULF Waves and inner-magnetosphere wave-particle interactions: modelling satellite and ground-based observations

ULF 波和磁层内波粒相互作用：模拟卫星和地面观测

• 批准号: RGPIN-2015-06569
• 负责人: Rankin, Robert
• 金额: $ 3.06万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=762560
• 关键词: ULF; Waves; inner; magnetosphere; wave

The primary objective is to use data from high profile Canadian and international satellite missions to constrain and validate advanced computer models that predict space weather resulting from a global distribution of ultra low frequency (ULF) plasma waves in Earth's magnetosphere. These waves are particularly intense in the recovery phase of geomagnetic storms and cause substantial atmospheric heating and ionization, ion outflows, and scattering of energetic particles to the atmosphere. This scattering represents a significant loss mechanism for Earth's radiation belts. Computer models will be developed to answer fundamental questions about particle acceleration in the inner magnetosphere and auroral zone, and about processes affecting the high latitude neutral atmosphere and ionosphere. The models will be used to interpret observations of ULF waves and charged particle precipitation made by Canadian ground-based arrays of magnetometers, optical and particle imagers, HF-radar, and VLF and GPS receivers.   The expected outcome is new modelling capabilities to assess how ULF waves drive space weather affecting satellites, power grids, and astronauts working in regions of space exposed to solar radiation. The methodology involves development of simulation codes that solve complex systems of physical equations describing plasma wave propagation through the magnetosphere, ionosphere, and neutral atmosphere, pitch-angle diffusion, and drift- and drift-bounce-resonance wave-particle interactions. The development of a global wave model coupled with a realistic time-dependent ionosphere and neutral atmosphere will facilitate remote sensing of cold plasma dynamics affecting acceleration and loss in the radiation belts. This model, along with other models, will be used to predict global properties of ULF waves that are excited externally by the direct action of the solar wind, and internally as a result of inner magnetosphere plasma instabilities. The models will also be used to understand how ULF waves couple with the ionosphere via geomagnetic field-aligned currents and time-dependent Hall and Pedersen currents. Higher frequency whistler and kinetic scale Alfven waves that scatter and accelerate charged particles into the auroral zone will also be investigated. These studies will make use of previously developed kinetic Vlasov and ray-tracing simulation models. The proposed studies on ULF waves are aligned with objectives of the NASA Van Allan Probes and THEMIS missions, and the Canadian Enhanced Polar Outflow Probe and European SWARM missions. They are also aligned with the new Canadian Space Agency ground-based GO-Canada program. A secondary objective is to utilize experience developing plasma simulation codes to understand solar wind interactions with the Moon and comets. Training that is planned is intended to attract and inspire a new generation of space scientists.

主要目标是利用加拿大和国际卫星任务的数据来约束和验证先进的计算机模型，这些模型可以预测地球磁层中超低频（ULF）等离子体波的全球分布所产生的空间天气。这些波在地球磁层中特别强烈。地磁风暴的恢复阶段，导致大量的大气加热和电离、离子流出以及高能粒子散射到大气中，这种散射代表了地球辐射带的重要损失机制。回答有关内磁层和极光区粒子加速以及影响高纬度中性大气和电离层的过程的基本问题。这些模型将用于解释加拿大地面阵列观测到的超低频波和带电粒子降水。磁力计、光学和粒子成像仪、高频雷达以及 VLF 和 GPS 接收器​预期成果是新的建模功能，用于评估 ULF 波如何驱动空间天气影响卫星、电网和在某些地区工作的宇航员。该方法涉及开发模拟代码，解决描述等离子体波通过磁层、电离层和中性大气传播、俯仰角扩散以及漂移和漂移反弹共振波的复杂物理方程系统。与现实的时间相关的电离层和中性大气相结合的全球波模型的发展将有助于影响辐射带加速和损失的冷等离子体动力学的遥感。预测全局属性ULF 波在外部由太阳风的直接作用激发，在内部则由于内部磁层等离子体的不稳定性而激发。这些模型还将用于了解 ULF 波如何通过地磁场对准电流和时间与电离层耦合。还将研究将带电粒子散射并加速到极光区的高频哨声和动力学尺度阿尔文波。这些研究将利用先前开发的动力学弗拉索夫和动力学波。拟议的 ULF 波研究与 NASA Van Allan 探测器和 THEMIS 任务以及加拿大增强型极地流出探测器和欧洲 SWARM 任务的目标一致。它们也与加拿大航天局的新地面任务一致。基于 GO-Canada 计划的第二个目标是利用开发等离子体模拟代码的经验来了解太阳风与月球和彗星的相互作用，计划的培训旨在吸引和激励新一代太空科学家。