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: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=663004
• 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. **

主要目标是使用来自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导致的空间天气。这些波在地磁风暴的恢复阶段特别强烈，引起大量的大气加热和电离，离子外流，以及高能粒子向大气的散射。这种散射代表了地球辐射带的一种重要损失机制。将开发计算机模型来回答有关内磁层和极光区的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由加拿大地面磁力计阵列、光学和粒子成像仪、高频雷达、VLF和GPS接收器所做的超低频波和带电粒子降水观测。预期的结果是新的建模能力，以评估超短波波如何驱动空间天气，影响卫星、电网和在暴露于太阳辐射的空间区域工作的宇航员。该方法涉及开发模拟代码，以解决描述等离子体波通过磁层、电离层和中性大气传播、俯角扩散以及漂移和漂移-反弹-共振波粒相互作用的复杂物理方程组。全球波模型的发展与真实的随时间变化的电离层和中性大气相结合，将有助于遥感影响辐射带加速和损失的冷等离子体动力学。这个模型，连同其他模型，将被用来预测ULF波的全局特性，ULF波的外部是由太阳风的直接作用激发的，内部是由内部磁层等离子体不稳定引起的。这些模型还将用于了解超高频波如何通过地磁场定向电流和随时间变化的霍尔和彼得森电流与电离层耦合。更高频率的哨声和动力学尺度的阿尔芬波散射和加速带电粒子进入极光区也将被研究。这些研究将利用先前开发的动力学Vlasov和光线追踪模拟模型。对极低频波的拟议研究与NASA Van Allan探测器和THEMIS任务、加拿大增强型极流探测器和欧洲SWARM任务的目标一致。它们还与加拿大航天局新的地面GO-Canada计划保持一致。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。计划中的培训旨在吸引和激励新一代空间科学家。**