权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

CEDAR: AMISR Measurements of Auroral Disturbance Electrodynamics, Including Relations to Harang Reversal and Large-Scale Convection Evolution

CEDAR：极光扰动电动力学的 AMISR 测量，包括与哈朗反转和大规模对流演化的关系

基本信息

批准号：
0639312
负责人：
Lawrence Lyons
金额：
$ 40万
依托单位：
University of California-Los Angeles
依托单位国家：
美国
项目类别：
Continuing Grant
财政年份：
2007
资助国家：
美国
起止时间：
2007-01-15 至 2010-12-31
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=0639312&HistoricalAwards=false
关键词：
CEDAR AMISR Measurements Auroral Disturbance

项目摘要

Two-dimensional ionospheric electrodynamics of auroral disturbances are studied with high time resolution using the Advanced Modular Incoherent Scatter Radar (AMISR) at the Poker Flat Rocket Range in Alaska. The electrodynamics associated with the nighttime electric field reversal (known as the Harang discontinuity) and with the temporal evolution of polar-cap convection strength are specific observation targets, and the primary research objective is to understand the physics governing large-scale plasma sheet transport and the electrodynamic coupling of that transport to the ionosphere. Magnetic substorm onsets, substorm growth phase auroral arcs, dynamic pressure disturbances, and auroral poleward boundary intensifications - all of which couple to plasma sheet convection, are included as observational targets of interest for which the electrodynamics of formation, evolution, and decay are established and compared to current substorm theory. In addition, the electrodynamics associated with aurora caused by Alfvenic wave electron acceleration are contrasted with the aurora triggered by static field-aligned potential drops (Inverted-V aurora). The AMISR measurements are placed into a larger regional context of auroral evolution by use of data from optical imagers and magnetometers in Alaska. The strength and evolution of convection in the polar cap is determined using simultaneous measurements from AMISR, the Sondrestromfjord incoherent scatter radar, and the EISCAT Svalbard incoherent scatter radar.

利用先进模块非相干散射雷达（AMISR）在阿拉斯加的Poker Flat Rocket Range以高时间分辨率研究了极光扰动的二维电离层电动力学。与夜间电场逆转（称为哈朗不连续）和极帽对流强度的时间演变相关的电动力学是具体的观测目标，主要研究目标是了解大规模等离子体片输运的物理规律以及这种输运到电离层的电动力学耦合。磁亚暴爆发、亚暴生长阶段极光弧、动态压力扰动和极光极向边界增强——所有这些都与等离子体片对流耦合，作为感兴趣的观测目标，建立了形成、演化和衰减的电动力学，并与当前的亚暴理论进行了比较。此外，将阿尔芬尼波电子加速引起的与极光相关的电动力学与静态场对准电位下降引发的极光（倒v极光）进行了对比。利用阿拉斯加州光学成像仪和磁力计的数据，将AMISR测量结果置于更大的极光演变区域背景中。利用AMISR、Sondrestromfjord非相干散射雷达和EISCAT Svalbard非相干散射雷达的同时测量，确定了极帽对流的强度和演变。