The physics controlling radiation belt dynamics

这项研究将调查控制近地空间区域内被称为内外辐射带的“空间天气”效应的物理过程。当地球辐射带的高能粒子含量急剧增强时，对“空间天气”非常感兴趣。辐射带增强对辐射带内运行的卫星基础设施和对这些区域进行磁测绘的地面系统的不利后果可产生重大的社会经济影响。英国国家民事紧急事件风险登记册将空间天气归类为一种发生几率相对较高、对英国社会影响较大的新风险。根据英国首相和美国总统的高级科学顾问的说法，仅在美国，极端空间天气事件的潜在成本估计为2万亿美元，预计需要4-10年的恢复期。此外，预计在这些扰动期间从辐射带逸出的粒子也会通过改变高层大气中的氮氧化物水平对大气化学产生一些影响，从而对全球温度产生影响。因此，需要研究控制空间天气影响的一般物理过程，特别是地球内外辐射带的动力学，不仅要了解如何减轻这些干扰的社会经济影响，而且要更充分地了解全球气候变化。在受干扰的空间天气事件中，辐射带可能会被激活、耗尽或完全消失，有时只是向地球移动或远离地球。事实上，观测表明，在某些事件中可以形成第三条带。这些突然而剧烈的变化被认为是电磁波在辐射带中捕获粒子，通过辐射带传输粒子，并将粒子散射到地球大气层的结果。目前，这些过程中没有一个是完全了解的，这些过程的各种驱动因素之间的联系和相互作用需要更好地量化，以便推动我们对辐射带动力学的理解。因此，这项研究的最终目标是确定控制辐射带中粒子动力学的电磁波类型，并发现在这些相互作用下导致辐射带的激活、耗尽和/或运动的条件。这项研究将允许开发基于预测物理的模型，可以预测辐射带的状态，以帮助制定减轻空间天气对现代社会影响的战略。

This research will investigate the physical processes governing 'Space Weather' effects within the regions of near-Earth space known as the inner and outer radiation belts. Times when the energetic particle content of the Earth's radiation belts becomes dramatically enhanced are of great 'Space Weather' interest. The adverse consequences of radiation belt enhancements for both satellite infrastructure operating within the radiation belts and to ground-based systems which magnetically map to these regions can have a significant socio-economic impact. The UK National Risk Register for Civil Emergencies has classified Space Weather as a new risk with relatively high chance of occurrence and high impact on UK society. According to senior science advisors to the UK Prime Minister and the US President, the potential cost of an extreme Space Weather event is estimated as $2 Trillion in the following year, in the U.S. alone, with a projected need for a 4-10 year recovery period. Moreover, particles escaping from the radiation belts during these disturbed periods are also predicted to have some impact on atmospheric chemistry and as a result global temperature by altering Nitrogen Oxide levels in the upper atmosphere. Thus research into physical processes governing Space Weather effects in general and the dynamics of the Earth's inner and outer radiation belts in particular is required to not only learn how to mitigate the socio-economic impact of these disturbances but also to more fully understand global climate change.During disturbed Space Weather events the radiation belts may become energised, depleted or completely disappear, and sometimes simply move toward or away from the Earth. In fact, observations demonstrate that during certain events a third belt can form. These abrupt and dramatic changes are thought to be the result of electromagnetic waves trapping particles in the radiation belts, transporting particles through the belts, and scattering particles into the Earth's atmosphere. At present, none of these processes are fully understood, and the links and interactions between the various drivers of these processes need to be better quantified in order to move our understanding of the dynamics of the radiation belts forward. The ultimate goal of this research is thus to determine the types of electromagnetic waves which control particle dynamics in the radiation belts and to discover the conditions under which these interactions lead to the energisation, depletion, and/or movement of the belts. This research will allow the development predictive physics-based models which can forecast the state of the radiation belts in order to help develop strategies to mitigate the effects of space weather on modern society.