Understanding Van Allen Radiation Belt loss processes and their impact on the upper atmosphere

作为一个天体，地球磁层似乎是一个相当安静的主体，由缓慢的动力学过程和小磁场主导。然而，在我们的环境中有货车艾伦辐射带--相对论等离子体的环形区域，其起源和行为是激烈的科学辩论的主题。现代社会越来越依赖于居住在这一区域的天基基础设施，以提供关键服务，如地球观测、国防、电信、GPS导航、电子银行和高能粒子沉淀影响高层大气化学的方式，我们现在才开始探索。辐射带是由一个复杂的相互作用之间的加速，运输和损失过程。我们开始了解加速和传输，但了解相对论性电子损失是辐射带物理学中最大的未知数。电子可以直接通过磁层的外边界损失，也可以通过粒子沉降进入电离层，导致化学变化和高层大气动力学变化。本项目将首次量化地磁活动增强期间的损失过程，如日冕物质抛射。我们将研究来自国际卫星任务的高能粒子数据，如美国宇航局的货车艾伦探测器，以及一个全球性的地基电离层网络，以验证我们对辐射带的理论理解的基石。

As an astrophysical object, the Earth's magnetosphere appears a rather quiescent body dominated by slow dynamical processes and small magnetic fields. However, within our environment are the Van Allen Radiation Belts - torus-shaped regions of relativistic plasma whose origins and behaviour are subjects of fierce scientific debate.Modern society is increasingly reliant on the space-based infrastructure that inhabit this region for critical services such as Earth observation, defence, telecommunications, GPS navigation, and electronic banking and energetic particle precipitation affects upper atmospheric chemistry in ways that we are only now beginning to explore.The Radiation Belts are governed by a complex interplay between acceleration, transport and loss processes. We are starting to understand acceleration and transport, but understanding relativistic electron loss is the big unknown in Radiation Belt physics. Electrons can be lost directly through the outer boundary of the magnetosphere, or via particle precipitation into the ionosphere contributing to chemistry changes and upper atmospheric dynamical changes.This project will make the first quantifications of loss processes during heightened geomagnetic activity, such as CMEs. We will study energetic particle data from international satellite missions such as the NASA Van Allen Probes, and a worldwide ground-based ionospheric network to validate the bedrock of our theoretical understanding of the Radiation Belts.