CEDAR: High-Spectral Width High Frequency (HF) Radar Ionospheric Backscatter with Coordinated Incoherent Scatter Radar (ISR) Diagnostic Observations

CEDAR：高谱宽高频 (HF) 雷达电离层反向散射与协调非相干散射雷达 (ISR) 诊断观测

• 批准号: 0535377
• 负责人: Gerard Blanchard
• 金额: $ 21.78万
• 依托单位: Southeastern Louisiana University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0535377&HistoricalAwards=false
• 关键词: CEDAR; Spectral; Width; Frequency; HF

The investigators will coordinate operations between the Kodiak High Frequency (HF) radar and the Advanced Modular Incoherent Scatter Radar (AMISR) in Alaska for the purpose of investigating the factors that affect the spectral width of HF radar coherent ionospheric backscatter as observed by the Super Dual Auroral Radar Network (SuperDARN). The two radars will probe a common ionospheric volume. AMISR (together with atmospheric modeling) will provide data on the ionsopheric conditions in the scattering volume: electron density, electron, ion and neutral temperature, electrical conductivities, current, and field, as well as heating rates and ionization rates. Kodiak will operate in two modes, the SuperDARN common mode and a special high spatial and temporal resolution mode made possible by improvements to the Kodiak transmitters. In the common mode, Kodiak will gather data that is comparable to the other SuperDARN radars. In the mode using special pulse compression methods, Kodiak will gather data on shorter time scales and on smallers spatial scales than in the common mode. The data will be analyzed to determine environmental conditions and sub-integration period or sub-range gate length variations in the scatter process that affect the common mode spectral width. The backscatter spectral width is one of the three quantities calculated from the HF radar coherent backscatter spectrum: total backscattered power, mean Doppler velocity, and spectral width. The spectral width has been shown by several studies to be useful for the purpose of identifying the ionospheric projection of magnetospheric regions and boundaries: the cusp, the low latitude boundary layer, and the open-closed magnetic field line separatrix. The latter is very important since a means to track the open-closed field line separatrix is necessary for measurements of the magnetospheric reconnection rate. However, there is currently no accepted theoretical explanation for the variations of the spectral width that identify these regions and boundaries. This project will provide precise data on which to base a theory of the spectral width so that the information contained in the spectral width data may be properly interpreted. The results of this project will enable better measurement of the magnetospheric reconnection rate and consequent improvement in space weather forecasting with tangible benefits for the aerospace industry and society at large. This project will also integrate research and education by advancing discovery and understanding while at the same time promoting teaching, training, and learning by employing at least two and probably three undergraduate physics majors as research assistants. This award is co-funded by EPSCOR because it is collaborative in nature between two EPSCOR jurisdictions (Louisiana and Alaska).

研究人员将协调阿拉斯加的科迪亚克高频（HF）雷达和先进模块化非相干散射雷达（AMISR）之间的操作，以调查影响超级双极光雷达网络（SuperDARN）观测到的高频雷达相干电离层反向散射谱宽的因素。两个雷达将探测共同的电离层体积。 AMISR（与大气建模一起）将提供有关散射体积中电离层条件的数据：电子密度、电子、离子和中性温度、电导率、电流和场，以及加热速率和电离速率。 Kodiak 将以两种模式运行：SuperDARN 普通模式和通过改进 Kodiak 发射机而实现的特殊高空间和时间分辨率模式。在普通模式下，Kodiak 将收集与其他 SuperDARN 雷达相当的数据。在使用特殊脉冲压缩方法的模式下，Kodiak 将在比普通模式更短的时间尺度和更小的空间尺度上收集数据。将分析数据以确定影响共模谱宽度的环境条件和子积分周期或散射过程中的子范围栅极长度变化。反向散射谱宽是根据高频雷达相干反向散射谱计算出的三个量之一：总反向散射功率、平均多普勒速度和谱宽。多项研究表明，谱宽对于识别磁层区域和边界的电离层投影非常有用：尖点、低纬度边界层和开闭磁场线分界线。后者非常重要，因为跟踪开闭场线分界线的方法对于测量磁层重联率是必要的。然而，目前对于识别这些区域和边界的光谱宽度的变化还没有公认的理论解释。该项目将提供精确的数据作为谱宽理论的基础，以便可以正确解释谱宽数据中包含的信息。该项目的结果将能够更好地测量磁层重联率，从而改善空间天气预报，为航空航天业和整个社会带来切实的好处。该项目还将通过促进发现和理解来整合研究和教育，同时通过雇用至少两名甚至可能三名物理专业的本科生作为研究助理来促进教学、培训和学习。该奖项由 EPSCOR 共同资助，因为它本质上是两个 EPSCOR 管辖区（路易斯安那州和阿拉斯加）之间的合作。