Instrument-Cluster Studies of Equatorial Spread F

赤道传播 F 的仪器集群研究

• 批准号: 1242815
• 负责人: Roland Tsunoda
• 金额: $ 62.99万
• 依托单位: SRI International
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-06-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1242815&HistoricalAwards=false
• 关键词: Instrument; Cluster; Studies; Equatorial; Spread

The investigators will study the cause of the day-to-day variability in the development of plasma structure in the equatorial layer referred to as equatorial spread (ESF). The study will be based on the hypothesis that ESF originates from large-scale wave structure (LSWS). LSWS is an altitude modulation of isodensity contours in the bottomside layer that grows to large amplitudes. The modulation alters the background conditions that control development of ESF and features such as equatorial plasma bubbles (EPBs), a behavior that is of considerable interest to space weather. LSWS has been ignored almost completely by researchers for good reasons. Experimentalists have been unaware of its existence, and theorists have not considered it because its importance remained questionable. However, recent observations have shown that LSWS is real, occurs frequently in the evening equatorial layer, and appears to play a substantial role in the day-to-day variability of ESF and EPBs. The objectives of the study are twofold: (1) to extract as much information as possible about LSWS from well-designed experiments, data analysis, and theoretical studies, and (2) to investigate the day-to-day variability problem through a series of tasks that can test the working hypotheses. New paradigms will be constructed following those tests, and that cycle will be repeated throughout the course of the project. The studies will revolve around the analyses of unique databases and new experiments that will take advantage of a unique cluster of instruments, which is capable of extracting the properties of LSWS. The cluster is unique because it can distinguish spatial from temporal variations, and LSWS is essentially a stationary spatial structure during its growth phase. The goal of the project is to obtain a comprehensive description of LSWS, and derive considerable insight about seeding, LSWS amplification, and the development of EPBs. The results will also validate the crucial need for instrument clusters in studies of ESF.

研究人员将研究赤道层等离子体结构发展中每日变化的原因，即赤道扩散（ESF）。该研究将基于ESF起源于大尺度波结构（LSWS）的假设。LSWS是底层等密度等高线的高度调制，其振幅会增大。调制改变了控制ESF发展的背景条件和赤道等离子体气泡（EPBs）等特征，这是对空间天气相当感兴趣的行为。LSWS几乎完全被研究人员忽视是有充分理由的。实验学家一直没有意识到它的存在，理论家也没有考虑到它，因为它的重要性仍然值得怀疑。然而，最近的观测表明，LSWS是真实存在的，经常发生在赤道傍晚层，并且似乎在ESF和epb的日常变化中起着重要作用。本研究的目的有两个：(1)从精心设计的实验、数据分析和理论研究中提取尽可能多的关于LSWS的信息；(2)通过一系列可以检验工作假设的任务来调查日常变异性问题。在这些测试之后将构建新的范例，并且该循环将在整个项目过程中重复。这些研究将围绕独特数据库的分析和新的实验展开，这些实验将利用独特的仪器集群，能够提取LSWS的特性。该集群的独特之处在于它可以区分空间和时间变化，并且在其生长阶段，LSWS本质上是一个平稳的空间结构。该项目的目标是获得LSWS的全面描述，并获得关于播种，LSWS扩增和epb开发的相当大的见解。研究结果还将验证ESF研究中对仪表组的关键需求。