Acceleration of Radiation Belt Electrons: In Situ Heating vs. Inward Radial Transport

地球辐射带中的电子可能会通过辐射损伤和深层介质充电对航天器电子设备产生严重影响。控制这些高能电子可变性的物理机制仍然是争论的热点。最近，解释电子辐射带产生的范式已经从只使用径向扩散理论转变为包括等离子体波的重要作用的范式。等离子体波与电子的相互作用可导致就地加热。该项目将研究径向扩散和就地加热对地球同步轨道内MeV电子增强的相对贡献。一个内部源项将被添加到当前的径向扩散模型中。将使用洛斯阿拉莫斯国家实验室(LANL)卫星数据对地球同步轨道上的电子进行测量，以确定源人口。实际的损失率将根据SAMPEX卫星的数据确定。然后将模型结果与地球同步轨道内的GPS卫星测量结果进行比较。这样，就有可能确定GPS测量到的MeV电子的增强在多大程度上可以归因于向内的径向输运，有多少可以归因于原位加热。该项目将包括研究生的研究和培训。这一结果将增强我们预测一种重要空间天气现象的能力。

Electrons in Earth's radiation belts can have serious effects on spacecraft electronics through radiation damage and deep dielectric charging. The physical mechanisms governing the variability of these energetic electrons are still hot topics of debate. The paradigm for explaining the creation of the electron radiation belts has recently been shifting from one using only the theory of radial diffusion to one including an important role for plasma waves. The interaction of plasma waves with the electrons can result in in situ heating. This project will investigate the relative contribution of radial diffusion and in situ heating to the enhancement of MeV electrons inside geosynchronous orbit. An internal source term will be added to a currently existing radial diffusion model. Measurements of electrons using Los Alamos National Laboratory (LANL) satellite data at geosynchronous orbit will be used to determine the source population. Realistic loss rates will be determined from data taken from the SAMPEX satellite. The model results will then be compared to GPS satellite measurements inside geosynchronous orbit. In this way, it will be possible to determine how much enhancement of the MeV electrons measured by GPS can be attributed to inward radial transport and how much to in situ heating. This project will include research and training for graduate students. The results will enhance our ability to predict an important space weather phenomenon.