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

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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.