Modelling the acceleration, transport and loss of radiation belt electrons to protect satellites from space weather (Rad-Sat)

对辐射带电子的加速、传输和损失进行建模，以保护卫星免受空间天气的影响 (Rad-Sat)

基本信息

批准号：
NE/P017274/1
负责人：
Clare Emily Jane Watt
金额：
$ 50.36万
依托单位：
University of Reading
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2017
资助国家：
英国
起止时间：
2017 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FP017274%2F1
关键词：
Modelling acceleration transport loss radiation

项目摘要

Over the last 10 years the number of operational satellites in orbit has grown from 450 to more than 1300. We rely on these satellites more than ever before for a wide range of applications such as mobile phones, TV signals, internet, navigation and financial services. All these satellites must be designed to withstand the harsh radiation environment in space for a design life that can be as long as 15 years or more. Space weather events can increase electron radiation levels by five orders of magnitude in the Earth's Van Allen radiation belts causing satellite charging, disruption to satellite operations and sometimes satellite loss. For example, in 2003 it was estimated that at least 10% of all operational satellites suffered anomalies (malfunctions [1]) during a large space weather event known as the Halloween storm. It is therefore important to understand how and why radiation levels vary so much so that engineers and business can assess impact and develop mitigation measures. New results from the NASA Van Allen Probes and THEMIS satellite missions show that wave-particle interactions play the major role in the acceleration, transport and loss of high energy electrons and hence the variability of the radiation belts. This proposal brings together scientists from across the UK with stakeholders from the insurance and satellite services sector. We will process data from scientific satellites such as Van Allen Probes and THEMIS to obtain information on four very important type of waves known as magnetosonic waves, and radio-waves known as plasmaspheric hiss, lightning generated whistlers and transmitter waves. We will use data, theory and models to determine the properties of the waves and how they vary during space weather events. We will conduct studies to assess the acceleration, transport and loss of electrons due to each wave type using quasi-linear theory. We will use simulations to test whether nonlinear effects result in more particle acceleration and loss compared to quasi-linear theory. We will analyse compressional magnetosonic waves in the ultra-low frequency range and determine their effectiveness for transporting electrons across the magnetic field, and whether the transport is diffusive or not. We will incorporate the results of these studies into our state-of-the-art global radiation belt model to simulate known space weather events, and compare the results against data to highlight the importance of the waves and improve the model. We will also include local time effects and compare loss rates against data from the ground and other satellites to constrain the model. We will simulate extreme space weather events using our existing radiation belt model, and an MHD model so that we can assess the role of waves in the rapid formation of a radiation belt such as occurred in 1991 in less than 2 minutes. We will develop a stakeholder community consisting of space insurance, satellite operators and forecasters who will provide input to our research and who will use the results for risk assessment, anomaly resolution and operational planning. The project will deliver new processed data, a better forecasting capability and expertise that will support the UK Government assessment of severe space weather for the National Risk Register [2] and the growth of the satellite industry.1. Cannon, P, S., et al. (2013), Extreme Space Weather: Impacts on Engineered Systems and Infrastructure, Royal Academy of Engineering, London, SW1A 2WH.2. Cabinet Office, (2012), National risk register of civil emergencies, Whitehall, London SW1A 2WH, www.cabinetoffice.gov.uk.

过去 10 年里，在轨运行的卫星数量从 450 颗增加到 1300 多颗。我们比以往任何时候都更加依赖这些卫星来实现移动电话、电视信号、互联网、导航和金融服务等广泛应用。所有这些卫星的设计都必须能够承受太空中恶劣的辐射环境，设计寿命可达15年或更长。太空天气事件可使地球范艾伦辐射带的电子辐射水平增加五个数量级，导致卫星充电、卫星运行中断，有时甚至导致卫星丢失。例如，据估计，2003 年，在一场被称为万圣节风暴的大型太空天气事件中，至少 10% 的运行卫星出现异常（故障 [1]）。因此，了解辐射水平如何以及为何变化如此之大非常重要，以便工程师和企业可以评估影响并制定缓解措施。美国宇航局范艾伦探测器和 THEMIS 卫星任务的新结果表明，波粒相互作用在高能电子的加速、传输和损失以及因此辐射带的变化中发挥着重要作用。该提案汇集了英国各地的科学家与保险和卫星服务行业的利益相关者。我们将处理来自范艾伦探测器和 THEMIS 等科学卫星的数据，以获得有关四种非常重要的波（称为磁声波）和无线电波（称为等离子层嘶嘶声、闪电产生的哨声和发射波）的信息。我们将使用数据、理论和模型来确定波浪的特性以及它们在太空天气事件期间如何变化。我们将使用准线性理论进行研究，评估每种波类型导致的电子加速、传输和损失。我们将使用模拟来测试与准线性理论相比，非线性效应是否会导致更多的粒子加速和损失。我们将分析超低频范围内的压缩磁声波，并确定其在磁场中传输电子的有效性，以及传输是否是扩散的。我们将把这些研究的结果纳入我们最先进的全球辐射带模型中，以模拟已知的空间天气事件，并将结果与数据进行比较，以强调波浪的重要性并改进模型。我们还将考虑本地时间影响，并将丢失率与地面和其他卫星的数据进行比较，以约束模型。我们将使用现有的辐射带模型和 MHD 模型来模拟极端空间天气事件，以便我们能够评估波在辐射带快速形成中的作用，例如 1991 年在不到 2 分钟内发生的情况。我们将建立一个由太空保险、卫星运营商和预报员组成的利益相关者社区，他们将为我们的研究提供投入，并将结果用于风险评估、异常解决和运营规划。该项目将提供新的处理数据、更好的预测能力和专业知识，以支持英国政府对国家风险登记册 [2] 的恶劣空间天气评估以及卫星行业的发展。1。 Cannon，P，S.，等人。 (2013)，极端空间天气：对工程系统和基础设施的影响，皇家工程院，伦敦，SW1A 2WH.2。内阁办公室，（2012 年），国家民事紧急情况风险登记册，白厅，伦敦 SW1A 2WH，www.cabinetoffice.gov.uk。