Acceleration and loss processes at relativistic energies: Sources and sinks of radiation belt plasma.

相对论能量下的加速和损失过程：辐射带等离子体的源和汇。

• 批准号: ST/G002401/1
• 负责人: Michael Denton
• 金额: $ 36.1万
• 依托单位: Lancaster University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2009
• 资助国家: 英国
• 起止时间: 2009 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=ST%2FG002401%2F1
• 关键词: Acceleration; loss; processes; relativistic; energies

The Earth's radiation belts are toroidal regions above the upper atmosphere where highly-energetic charged particles orbit the planet with periods of typically a few minutes. In addition to being a ready-made scientific laboratory in which to study the sources, the energisation mechanisms, and the loss of relativistic-energy electrons and ions, the radiation belts also pose a significant hazard to orbital hardware (and humans). Whilst the presence of the radiation belts has been known since the dawn of the space age, an understanding of the processes which cause radiation belt production and loss has still not been achieved, although recent work has identified some of the most probable particle-acceleration mechanisms. There is currently no reliable method to predict the particle flux within the radiation belts. Indeed, when measured at geosynchronous orbit the flux can change by up to five orders of magnitude within 24 hours - the flux of radiation-belt particles may increase, decrease (dropout), or remain the same during apparently similar conditions. Resolving the complex interplay between competing physical mechanisms within the radiation belts is the primary focus of this research project. A three-year research programme, outlined below, will build on previous work to significantly enhance our physical understanding of the radiation belts - the aim being to determine the primary production and loss mechanisms within them. As well as studying the elementary physics at play within this region (e.g. wave-particle energisation/loss mechanisms), a by-product of the research will be the production of predictive models to specify the flux of particles in the belts, based on the prevailing conditions.

地球的辐射带是高层大气上方的环形区域，高能带电粒子围绕地球运行，周期通常为几分钟。除了是一个现成的科学实验室，在其中研究来源、能量机制和相对论能量电子和离子的损失，辐射带还对轨道硬件(和人类)构成重大危险。虽然从空间时代开始就知道辐射带的存在，但对造成辐射带产生和损失的过程的理解仍然没有实现，尽管最近的工作已经确定了一些最可能的粒子加速机制。目前还没有可靠的方法来预测辐射带内的粒子通量。事实上，当在地球同步轨道上测量时，通量可以在24小时内变化多达五个数量级-辐射带粒子的通量可能在明显相似的条件下增加、减少(丢失)或保持不变。解决辐射带内相互竞争的物理机制之间的复杂相互作用是本研究项目的主要重点。下文概述的一项为期三年的研究方案将在以前工作的基础上，大大加强我们对辐射带的实际了解--目的是确定辐射带内的主要生产和损失机制。除了研究这一区域内正在发挥作用的基本物理(例如，波粒激发/损失机制)外，研究的一个副产品将是根据当时的条件生产预测模型，以确定带中的粒子通量。

项目成果

A survey of the anisotropy of the outer electron radiation belt during high-speed-stream-driven storms RADIATION BELT ANISOTROPY

高速流驱动风暴期间外电子辐射带各向异性的调查 辐射带各向异性

• DOI: 10.1029/2010ja016151
• 发表时间: 2011
• 期刊: Space Physics
• 作者: Borovsky J

Density and temperature of energetic electrons in the Earth's magnetotail derived from high-latitude GPS observations during the declining phase of the solar cycle

太阳周期衰退阶段高纬度 GPS 观测得出的地球磁尾中高能电子的密度和温度

• DOI: 10.5194/angeo-29-1755-2011
• 发表时间: 2011
• 期刊: Annales Geophysicae
• 影响因子: 1.9
• 作者: Denton M

NO EVIDENCE FOR HEATING OF THE SOLAR WIND AT STRONG CURRENT SHEETS

• DOI: 10.1088/2041-8205/739/2/l61
• 发表时间: 2011-10
• 期刊: The Astrophysical Journal Letters
• 作者: J. Borovsky;M. Denton

Magnetosphere response to high-speed solar wind streams: A comparison of weak and strong driving and the importance of extended periods of fast solar wind

• DOI: 10.1029/2011ja017124
• 发表时间: 2012-09
• 期刊: Journal of Geophysical Research
• 作者: M. Denton;J. Borovsky

Inner magnetospheric heavy ion composition during high-speed stream-driven storms

高速流驱动风暴期间内磁层重离子成分

• DOI: 10.1002/jgra.50292
• 发表时间: 2013
• 期刊: Space Physics
• 作者: Forster D