CEDAR: Clustered, Multi-Frequency Studies of the Thermosphere, Exosphere, and Topside Ionosphere

研究人员继续描述中纬度热层上层、外逸层和顶侧电离层的组成和动态。 该方法使用光学，红外和雷达频率遥感技术，与辐射传输，光电子，中性大气和电离层建模密切相关。 特别是，他们希望提高对顶侧F区离子中性耦合的理解。 实验和建模工作使阿雷西博天文台具备了使用群集仪器测量顶侧电离层所有主要中性和离子种类浓度的新能力。 该项目将这些技术结合在一起，对上部热层和下部外逸层进行全面描述。 在科学方面，他们的重点是（1）电离层顶部的氢丰度与对流层中甲烷增加之间的关系，（2）氢丰度与磁暴之间的关系，（3）电荷交换对中性氢和氧丰度的影响，以及（4）评估确定电离层顶部风和温度的新技术。 在六次观测活动中，研究人员利用法布里-珀罗干涉仪、光度计、全天空成像仪以及阿雷西博和希卡马卡的非相干散射雷达进行测量。

Investigators continue characterizing the composition and dynamics of the upper thermosphere, exosphere, and topside ionosphere at mid-latitude. The methodology uses optical, infrared, and radar frequency remotes sensing techniques, in close association with radiative transport, photoelectron, neutral atmosphere, and ionospheric modeling. In particular, they hope to improve understanding of ion-neutral coupling in the topside F-region. Experimental and modeling efforts have led to new capabilities in measuring the concentrations of all major neutral and ion species in the topside ionosphere using the clustered instrumentation at the Arecibo Observatory. This project brings the techniques together, producing a comprehensive description of the upper thermosphere and lower exosphere. Scientifically, their focus is (1) the relation between hydrogen abundance in the topside ionosphere and increased methane in the troposphere, (2) the relation between hydrogen abundance and magnetic storms, (3) the effects of charge exchange on neutral hydrogen and oxygen abundances, and (4) the evaluation of new techniques to determine winds and temperatures in the topside ionosphere. During six observational campaigns, investigators measurements are utilizing Fabry-Perot interferometers, photometers, all-sky imagers, and the incoherent scatter radars at Arecibo and Jicamarca.