CAREER: Quantifying Radiation Belt Precipitation and Atmospheric Impacts through D-region Ionosphere Imaging

来自太阳的高能粒子不断轰击地球。许多人被地球磁场困在一个称为辐射带的区域，该区域从640公里的高度延伸到58000公里。这些被捕获的高能粒子可以降落到极地的高层大气中（这一过程被称为粒子沉淀），与大气分子相互作用，产生了彩色的极光。一些非常高能的粒子可以进一步下降，将能量沉积到大气中，改变化学成分，影响全球能量平衡和循环。由于缺乏对从辐射带损失到大气中的粒子的测量，这些高能粒子的影响还没有得到很好的理解。CAREER项目概述了一项综合研究和教育计划，利用经济实惠的大规模成像技术，量化辐射带中的粒子损失及其对高层大气的影响。辐射带降水是磁层、电离层和大气之间的重要联系。首席研究员（PI）的研究目标是量化高能粒子降水（EPP）事件的通量、光谱、时空尺度、它们在高层大气中的化学效应以及它们对辐射带种群的影响。为了实现这些研究目标，PI将：i)在加拿大建立一个低成本、自主的极低频观测网络，以观测EPP在中高纬度d区电离层的变化；ii)利用基于集合卡尔曼滤波的反演技术，完善和提高我们对EPP特征和过程及其与辐射带损失关系的理解；iii)使用实际航天器数据验证结果。PI的教育目标是在科罗拉多大学博尔德分校建立一个强大的空间物理和工程本科和研究生教育和培训计划：i)为博士和本科生提供建议，同时保持PI在招募和支持女性和代表性不足的学生方面的记录；Ii)通过开设新的高级研究生课程，将研究成果纳入研究生空间物理课程；Iii)为高中生提供研究经验的机会；iv)通过在全校范围内开设关于空间环境及其影响的新本科课程和编写涵盖该课程材料的新教科书，促进非技术人员更广泛地了解空间物理学。对降水通量进行量化还将改进空间天气临近预报和预报，并对辐射带的航天器设计和操作产生影响；低地球轨道动力学与阻力；以及高空飞机的辐射安全。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。

High energy particles from the Sun constantly bombard the Earth. Many are trapped by the Earth’s magnetic field in a region called radiation belt, which extends from an altitude of about 640 to 58,000 km. These trapped high energy particles can come down to the upper atmosphere at polar region (a process called particle precipitation), interacting with atmospheric molecules to create the colorful aurora. Some very high energy particles can come further down, depositing energy into the atmosphere and altering the chemistry, and affecting global energy balance and circulation. The effects of these high energy particles are not well understood because of lack of measurements of the particles lost from the radiation belt into the atmosphere.This CAREER project outlines an integrated research and education initiative to quantify particle losses from the radiation belts and their effects in the upper atmosphere, using an affordable, large-scale imaging technique. Radiation belt precipitation forms a critical link between the magnetosphere, ionosphere, and atmosphere. The Principal Investigator (PI)'s research goal is to quantify the flux, spectra, spatial and temporal scales of energetic particle precipitation (EPP) events, their chemical effects in the upper atmosphere, and their effects on radiation belt populations. In pursuit of these research goals, the PI will: i) establish a low-cost, autonomous very-low-frequency observation network across Canada to observe variations due to EPP in the mid- to high-latitude D-region ionosphere; ii) refine and improve our understanding of EPP signatures and processes and their relationship to radiation belt losses using an ensemble Kalman Filter-based inversion technique; and iii) validate results using operational spacecraft data. The PI's education goal is to build a robust undergraduate and graduate education and training program in space physics and engineering at CU Boulder by: i) advising PhD and undergraduate students while maintaining the PI's track record for recruiting and supporting female and underrepresented students; ii) incorporating research outcomes into the graduate space physics curriculum through a new upper-level graduate course; iii) providing research experience opportunities to high school students; and iv) promoting broader understanding of space physics in the non-technical community through a new campus-wide undergraduate course on the space environment and its effects and a new textbook covering this course material.Quantifying precipitating fluxes will also lead to improved Space Weather nowcasting and forecasting and has implications for spacecraft design and operations in the radiation belts; orbital dynamics and drag in Low Earth Orbit; and radiation safety for high-altitude aircraft.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.