Collaborative Research: Causes and Consequences of Relativistic Electron Precipitation as Revealed by the CubeSat Mission ELFIN’s Pitch-Angle Resolved Loss Cone Measurements

合作研究：立方体卫星任务 ELFIN 的俯仰角解析损耗锥测量揭示的相对论电子沉淀的原因和后果

• 批准号: 2019950
• 负责人: Wen Li
• 金额: $ 12.03万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2019950&HistoricalAwards=false
• 关键词: Collaborative; Research; Causes; Consequences; Relativistic

The jointly funded NSF/NASA ELFIN mission consists of two identical CubeSats on a polar (~ 93 degree inclination), nearly circular, low-Earth orbit. ELFIN was launched on September 15, 2018 and is currently operating within the geospace environment. This funding will address the prime mission objective of analyzing the data currently being collected by ELFIN to advance understanding of wave-particle interactions and their effect on relativistic electrons in the outer radiation belt. Two undergraduate students, a graduate student, and three early career scientists will be supported. ELFIN data products are integrated into courses at UCLA and in public outreach events in the Los Angeles area.The project will utilize ELFIN, together with its conjunctions with other, equatorial Heliophysics missions to address the efficacy of EMIC wave precipitation, and the relative contribution of EMIC, whistlers and kinetic Alfvén waves in the observed relativistic electron scattering (100s of keV to a few MeV energy). The specific science objectives are: (1) Are EMIC waves responsible for 0.5-2MeV electron precipitation?(2) Are waves other than EMIC waves (principally chorus waves and kinetic Alfvén waves (KAWs)), also responsible for significant relativistic electron scattering? (3) What are the typical precipitation rates associated with various wave types as function of geomagnetic conditions?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.

美国国家科学基金会/美国航天局共同资助的ELFIN使命由两个相同的立方体卫星组成，它们位于极（倾角约93度）、近圆形的低地球轨道上。ELFIN于2018年9月15日发射，目前正在地球空间环境中运行。这笔资金将用于分析ELFIN目前收集的数据的主要使命目标，以促进对波粒相互作用及其对外辐射带中相对论电子的影响的理解。两名本科生，一名研究生和三名早期职业科学家将得到支持。该项目将利用ELFIN及其与其他赤道太阳物理学飞行任务的结合，研究EMIC波降水的效力，以及EMIC波、哨声和动力阿尔文波在观测到的相对论电子散射（100千电子伏至几兆电子伏的能量）中的相对贡献。具体的科学目标是：（1）EMIC波是否是0.5- 2 MeV电子沉淀的原因？(2)除了EMIC波（主要是合唱波和动力学阿尔文波（KAWs））之外，其他波是否也是重要的相对论电子散射的原因？(3)作为地磁条件的函数，与各种波型相关的典型降水率是多少？该奖项反映了NSF的法定使命，并被认为是值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估的支持。

项目成果

Parametric analysis of pitch angle scattering and losses of relativistic electrons by oblique EMIC waves

• DOI: 10.3389/fspas.2023.1163515
• 发表时间: 2023-04
• 作者: M. Hanzelka;Wen Li;Q. Ma

Identification and Classification of Relativistic Electron Precipitation at Earth Using Supervised Deep Learning

• DOI: 10.3389/fspas.2022.858990
• 发表时间: 2022-03
• 作者: L. Capannolo;Wen Li;Sheng Huang

Characteristics of Electron Precipitation Directly Driven by Poloidal ULF Waves

• DOI: 10.1029/2022ja031163
• 发表时间: 2023-02
• 期刊: Journal of Geophysical Research: Space Physics
• 作者: Z. Yin;Xuzhi Zhou;Wen Li;X. Shen;R. Rankin;Ji Liu;Zejun Hu;Jianjun Liu;Q. Zong; Li

Relativistic Electron Precipitation Near Midnight: Drivers, Distribution, and Properties

• DOI: 10.1029/2021ja030111
• 发表时间: 2022-01
• 期刊: Journal of Geophysical Research: Space Physics
• 作者: L. Capannolo;W. Li;R. Millan;D. Smith;Nithin Sivadas;J. Sample;S. Shekhar

Bursty Energetic Electron Precipitation by High‐Order Resonance With Very‐Oblique Whistler‐Mode Waves

• DOI: 10.1029/2022gl101920
• 发表时间: 2023-04
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: L. Gan;A. Artemyev;Wen Li;Xiao‐jia Zhang;Q. Ma;D. Mourenas;V. Angelopoulos;E. Tsai;C. Wilkins