The Generation of Banded Chorus Waves in the Earth's Radiation Belt

地球辐射带中带状合唱波的产生

• 批准号: 1923126
• 负责人: Jinxing Li
• 金额: $ 35.23万
• 依托单位: University of California-Los Angeles
• 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: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1923126&HistoricalAwards=false
• 关键词: Generation; Banded; Chorus; Waves; Earth

Radio waves are naturally produced in the near-Earth space environment. Chorus waves are a type of such radio waves that interact with relativistic particles in the radiation belts. Understanding the interactions between these waves and particles is important for predicting the changing space environment and its societal impacts. In particular, this allows us to predict space weather and prepare for impacts to national commercial and defense satellites and communications - a priority set out in the National Space Weather Action Plan. This project aims to explore the origin of banded chorus waves in Earth's radiation belt by analyzing data from the Van Allen Probes and performing particle-in-cell simulations to aid in interpretation. Naturally occurring chorus waves are believed to play a key role in accelerating relativistic electrons in the Earth's outer radiation belt, and in precipitating ~keV (and higher) electrons to the upper atmosphere, causing diffuse aurorae and pulsating aurorae. Chorus typically occurs in two distinct frequency bands separated by a gap at half of the electron gyro-frequency. The origin of this two-band structure has been a half-century-long open scientific question. This project, by systematically surveying the chorus waves and their properties right in the source region, will explore whether the spectral gap at half the electron gyro-frequency is generated at the magnetic equator, or is formed by damping as the waves propagate to higher latitudes. The electron distributions that accompany banded chorus waves will be statistically investigated and linear growth calculations made to investigate the direct energy source of banded chorus waves. Based on typical observations of waves and particle distribution, 1-Dimensional and 2-Dimensional particle-in-cell simulations will be performed to explore the multi-stage interaction processes that could account for the banded chorus waves.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.

无线电波是在近地太空环境中自然产生的。合唱波是这种无线电波与辐射带中相对论颗粒相互作用的一种类型。了解这些波和颗粒之间的相互作用对于预测空间环境的变化及其社会影响很重要。特别是，这使我们能够预测太空天气，并为国家商业和国防卫星和通讯的影响做准备，这是国家太空天气行动计划中的优先事项。该项目旨在通过分析Van Allen探针的数据并进行粒子中的模拟以帮助解释来探索地球辐射带中带状合唱波的起源。据信自然发生的合唱波在加速地球外辐射带加速相对论电子以及将较高的电子降压到上层大气中起着关键作用，从而导致弥漫性极光和脉冲极光。合唱通常发生在两个不同的频带中，这些频带在电子陀螺频频的一半处被一个间隙分开。这种两波段结构的起源是一个半个世纪的开放科学问题。该项目通过系统地测量合唱波及其在源区域中的特性，将探讨在磁性赤道处产生电子陀螺频频的一半的光谱间隙，还是通过阻尼时通过阻尼而形成，随着波传播到较高的纬度。统计研究将对带状合唱波的电子分布进行统计研究，并进行线性生长计算，以研究带状合唱波的直接能源。 Based on typical observations of waves and particle distribution, 1-Dimensional and 2-Dimensional particle-in-cell simulations will be performed to explore the multi-stage interaction processes that could account for the banded chorus waves.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.

项目成果

Unraveling the Formation Region and Frequency of Chorus Spectral Gaps

• DOI: 10.1029/2022gl100385
• 发表时间: 2022-09
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Jinxing Li;J. Bortnik;Wen Li;X. An;L. Lyons;W. Kurth;G. Hospodarsky;D. Hartley;G. Reeves

Multipoint Observations of Quasiperiodic Emission Intensification and Effects on Energetic Electron Precipitation

• DOI: 10.1029/2020ja028484
• 发表时间: 2021-01
• 期刊: Journal of Geophysical Research: Space Physics
• 作者: Jinxing Li;J. Bortnik;Q. Ma;Wen Li;X. Shen;Y. Nishimura;X. An;S. Thaller;A. Breneman;J. Wygant;W. Kurth;G. Hospodarsky;D. Hartley;G. Reeves;H. Funsten;J. Blake;H. Spence;D. Baker

Parallel Acceleration of Suprathermal Electrons Caused by Whistler‐Mode Hiss Waves

• DOI: 10.1029/2019gl085562
• 发表时间: 2019-11
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Jinxing Li;Q. Ma;J. Bortnik;Wen Li;X. An;G. Reeves;H. Funsten;H. Spence;D. Baker;W. Kurth;G. Hospodarsky;D. Hartley

Origin of two-band chorus in the radiation belt of Earth

• DOI: 10.1038/s41467-019-12561-3
• 发表时间: 2019-10
• 期刊: Nature Communications
• 影响因子: 16.6
• 作者: Jinxing Li;J. Bortnik;X. An;Wen Li;V. Angelopoulos;R. Thorne;C. Russell;B. Ni;X. Shen