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Development of an Integrated View of Plasma Instability Processes in the Lower Ionosphere

低电离层等离子体不稳定过程综合视图的发展

基本信息

批准号：
2028441
负责人：
Roman Makarevich
金额：
$ 32.97万
依托单位：
ATMOSPHERIC & SPACE TECHNOLOGY RESEARCH ASSOCIATES, L.L.C.
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2020
资助国家：
美国
起止时间：
2020-01-01 至 2021-05-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=2028441&HistoricalAwards=false
关键词：
Development Integrated View Plasma Instability

项目摘要

Earth's ionosphere is a mixture of neutral gas and charged particles. The ionosphere is generally broken out by layers, defined according to the wavelengths of the radiation most commonly absorbed. The E-region extends from 90-150 km and is ionized through X-ray and ultraviolet radiation. The F-region (150-600 km) is ionized by extreme ultraviolet radiation. Although waves and disturbances ("structuring") occur throughout the ionospheric medium ("plasma"), studies often focus on; either the E or F layer owing in part to limitations of experimental and theoretical; techniques employed. As a result, development of a unified view of ionospheric plasma structuring processes remains incomplete. This proposal will fill this gap by (1) developing a unified plasma instability theory applicable in the broad range of altitudes including the previously unexplored transitional valley region between the E and F region peaks and (2) observing the valley region with a radar that routinely receives returns from a broad range of altitudes. The proposed research leverages NSF assets and knowledge synthesis to contribute fundamentally to the theory of plasma instability and structuring. This knowledge is relevant to the communication and navigation industries, and therefore to society. The integrated theory will be incorporated into UAF plasma physics classes, that currently rely primarily on original journal publications rather than teaching modules. The proposal will also fund a new Ph.D. student.The proposed research will address the fundamental question of what combination of destabilizing and stabilizing factors results in the plasma perturbations growing in amplitude and producing ionospheric structures. The actual proposal activity consists of three interconnected projects: 1. Development a unified theory of ionospheric plasma instabilities including thermal, inertial, and gradient effects for arbitrary altitude and propagation; 2. Determination of the critical gradient length required to destabilize plasma in the non-isothermal case for arbitrary altitude; 3. Analysis of SuperDARN and ISR data to investigate small-scale irregularity occurrence in the previously unexplored transitional "valley" region (~150 km). These measurements are expected to provide support for a theory that strong gradients are required to make plasma unstable in the valley at small scales.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.

地球的电离层是中性气体和带电粒子的混合物。电离层通常分为几层，根据最常吸收的辐射波长定义。E区延伸90-150公里，通过X射线和紫外线辐射电离。F区（150-600公里）被极紫外辐射电离。虽然波和扰动（“结构”）发生在整个电离层介质（“等离子体”），但研究往往集中在E层或F层，部分原因是实验和理论的限制;所采用的技术。因此，电离层等离子体结构化过程的统一观点的发展仍然不完整。这项建议将填补这一空白，（1）发展一个统一的等离子体不稳定性理论，适用于广泛的高度范围，包括以前未探索的过渡谷区之间的E和F区的高峰和（2）观察谷区的雷达，定期接收返回从广泛的高度范围。拟议的研究利用NSF的资产和知识综合，从根本上促进等离子体不稳定性和结构的理论。这些知识与通信和导航行业相关，因此也与社会相关。综合理论将被纳入UAF等离子体物理课程，目前主要依靠原始期刊出版物，而不是教学模块。该提案还将资助一个新的博士学位。拟议的研究将解决这样一个根本问题，即不稳定因素和稳定因素的何种组合导致等离子体扰动的幅度增加并产生电离层结构。实际的提案活动包括三个相互关联的项目：1。发展一套适用于任意高度和传播的电离层等离子体不稳定性的统一理论，包括热效应、惯性效应和梯度效应; 2.确定了任意高度非等温条件下使等离子体失稳所需的临界梯度长度; 3.分析SuperDARN和ISR数据，以调查以前未探索的过渡“山谷”区域（~150 km）中的小尺度不规则性。这些测量预计将提供支持的理论，强梯度需要使等离子体不稳定的山谷在小scales.This奖项反映了美国国家科学基金会的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。