NSWP: Space Weather--Further Development of Empirical Models of Plasma Densities in Near-Earth Magnetosphere

NSWP：空间天气——近地磁层等离子体密度经验模型的进一步发展

• 批准号: 0518227
• 负责人: Paul Song
• 金额: $ 14.15万
• 依托单位: University of Massachusetts Lowell
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-10-01 至 2008-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0518227&HistoricalAwards=false
• 关键词: NSWP; Space; Weather; Further; Development

This project will study plasma density distributions and dynamics in the near-earth magnetosphere (plasmasphere, sub-auroral/auroral and polar cap region) by using data from the Radio Plasma Imager (RPI) on the IMAGE satellite. The active radio sounding of the RPI provides local plasma resonances and remotely reflected signals (echoes) that can be used to derive plasma densities in-situ at satellite locations, and remotely and instantaneously the density distributions along the magnetic field lines down to the altitude as low as approximately 3000 km. The RPI database has accumulated about one million measurements covering all local times from about 3000 km to 4 Re altitude under different geomagnetic activities and the database is still growing. This makes it possible to develop empirical density models as function of radial distance, latitude, local time, season, solar wind/interplanetary magnetic field (IMF) conditions, and geomagnetic activity indices. The RPI empirical models will be compared with topside density profiles from the International Reference Ionosphere (IRI). The statistical and event observations, as well as numerical simulations, will be utilized to provide insights to the plasma dynamics both for the average density distributions and actual events.

该项目将利用图像卫星上的无线电等离子成像仪的数据，研究近地磁层(等离子体层、亚极光/极光和极帽区域)中的等离子体密度分布和动力学。RPI的有源无线电探测提供了本地等离子体共振和远程反射信号(回波)，可用于在卫星位置就地推算等离子体密度，并远程和瞬时地计算低至约3000公里高度的磁力线上的密度分布。在不同的地磁活动下，RPI数据库已经积累了大约100万次测量，覆盖了从大约3000公里到4Re高度的所有当地时间，并且该数据库还在不断扩大。这使得建立作为径向距离、纬度、当地时间、季节、太阳风/行星际磁场(IMF)条件和地磁活动指数的函数的经验密度模型成为可能。RPI经验模型将与来自国际参考电离层(IRI)的顶部密度剖面进行比较。统计和事件观测以及数值模拟将被用来提供对平均密度分布和实际事件的等离子体动力学的洞察。