On the Source and Loss of Inner Belt Electrons

内带电子的来源与损失

• 批准号: 1834971
• 负责人: Xinlin Li
• 金额: $ 35.22万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1834971&HistoricalAwards=false
• 关键词: Source; Loss; Inner; Belt; Electrons

This project is a follow-on to successful NSF funded programs supporting the Colorado Student Space Weather Experiment (CSSWE) CubeSat. The CubeSat took measurements of energetic electrons in the Earth's radiation belts. Understanding the populations of inner radiation belt electrons is important to national security and commercial interests. The energetic electrons can damage or destroy space craft functioning. The resulting scientific results from the project will lead to improvement of predictive space weather models. This fits directly into the goals of the National Space Weather Strategy and Action Plan, released in 2015. The proposed work will fund a female graduate student in STEM and maximize the science return from the NSF funded CSSWE CubeSat. The CSSWE CubeSat recently discovered that Cosmic Ray Albedo Neutron Decay (CRAND) produces a population of electrons in the inner radiation belt and contributes to electron populations elsewhere in the radiation belts. The proposed research will determine the relative contribution of CRAND electrons in the inner belt, the solar cycle dependence of the CRAND population, and the pitch angle scattering rate and lifetime of trapped inner belt electrons. Electron observations from the CSSWE will be analyzed along with DEMETER/IDP and SAMPEX/PET satellite data. Established CRAND models incorporating diffusive small-angle atmospheric scattering and non-diffusive wide-angle scattering will be generated and fit to the satellite data. The proposed work is unique in that it seeks to understand the precipitation loss of inner radiation belt electrons including the contribution from the CRAND produced population. The CRAND population was not known to be significant before the new results from CSSWE published within the last few years.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

该项目是美国国家科学基金会资助的支持科罗拉多州学生空间天气实验(CSSWE)立方体卫星的成功项目的后续项目。立方体卫星测量了地球辐射带中的高能电子。了解内辐射带电子的数量对国家安全和商业利益具有重要意义。高能电子可以破坏或摧毁航天器的功能。该项目所产生的科学成果将导致空间天气预测模型的改进。这直接符合2015年发布的国家空间天气战略和行动计划的目标。这项拟议的工作将资助STEM的一名女研究生，并最大限度地提高NSF资助的CSSWE CubeSat的科学回报。CSSWE CubeSat最近发现，宇宙射线反常中子衰变(CRAND)在内辐射带产生一群电子，并对辐射带其他地方的电子群做出贡献。这项研究将确定内带中碳电子的相对贡献，碳原子数量与太阳周期的关系，以及捕获的内带电子的俯仰角散射率和寿命。来自CSSWE的电子观测将与Demeter/IDP和SAMPEX/PET卫星数据一起进行分析。将生成包含扩散小角大气散射和非扩散广角散射的CRAND模型，并将其与卫星数据进行拟合。这项拟议的工作的独特之处在于，它试图了解内辐射带电子的降水损失，包括来自CRD产生的人口的贡献。在CSSWE在过去几年内公布新的结果之前，人们并不知道克兰德人口的数量有多大。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Dynamics of Energetic Electrons in the Slot Region During Geomagnetically Quiet Times: Losses Due to Wave‐Particle Interactions Versus a Source From Cosmic Ray Albedo Neutron Decay (CRAND)

• DOI: 10.1029/2020ja028042
• 发表时间: 2020-09
• 期刊: Journal of Geophysical Research: Space Physics
• 作者: Z. Xiang;Xinlin Li;B. Ni;M. Temerin;Hong Zhao;Kun Zhang;L. Khoo