非相干散射雷达等离子体谱线增强机制研究

非相干散射雷达（ISR）等离子谱线的能量一般远低于雷达噪声水平，不易被检测到，但当电离层存在自然或者人工的能量和动量输入时，等离子谱线将被增强或者激发。由于等离子谱线来源于电离层中静电Langmuir波对雷达电波的散射，是电离层超热电子存在的直接证据，因而对非相干散射理论、电离层中微观等离子体物理过程、磁层电离层耦合等研究具有重要意义，是近年来的研究热点。本项目从自主开发ISR回波谱等离子谱线自动判读和提取技术入手，利用EISCAT一个太阳活动周的数据，结合卫星观测资料，深入全面地研究ISR等离子谱线回波机制以及等离子谱线出现规律和物理过程，包括自然和人工激发/增强等离子谱线特征和物理机制，并在此基础上比较和辩析两种情况下激发等离子谱线的异同，以及相应的等离子体湍流机制，进而探讨等离子谱线对太阳风-磁层能量动量注入的响应、自然/人工激发高纬电离层Langmuir湍流以及电子加速的物理过程。

The energy of the incoherent scattering radar (ISR) plasma line is generally much lower than the ISR radar noise level, which is not easy to detect, but when there is natural or artificial energy and momentum input to the ionosphere, the plasma line will be enhanced or excited. Because the plasma line is derived from the scattering of electrostatic Langmuir waves in the ionosphere to the radar waves, it is direct evidence of the existence of superthermal electrons in the ionosphere. Such research is of great significance and is a research hotspot in recent years. This project starts with the self-developed ISR echo spectrum plasma line automatic interpretation and extraction technology, by using EISCAT data of a solar activity cycle, combined with satellite observation data, to thoroughly study the ISR plasma line echo mechanism and the appearance law of plasma line physical processes, including the characteristics and physical mechanisms of natural and artificial excited / enhanced plasma lines, and on the basis of this comparison and analysis of the similarities and differences between the excitation plasma lines in two cases, as well as the corresponding plasma turbulence mechanism, and then explore how the plasma line in response to the solar wind-magnetosphere energy and momentum injection, the natural/artificial excitation of the high latitude ionospheric Langmuir turbulence and the physical process of electron acceleration.