Active Experiments/Electric Fields

这笔赠款将支持一项关于磁场排列或伯克兰电流的几种影响的研究。这些项目从一个标准模型磁层开始，各种伯克兰电流系统将被添加到该模型中。第一批增加将涉及典型的简化极光洋流系统。然后，将添加从特定雷达和地面磁强计测量得出的几个实际电流模式。该项目这一部分的目的是研究电场在伯克兰电流存在的情况下从电离层投射到外磁层时在方向和大小上的扭曲情况。这项研究的下一部分涉及磁通管的形成。这些管子是由伯克兰电流驱动的微扰磁场产生的。在极光亚风暴向西行进的高潮附近，在小而明亮的极光斑点附近，以及在极冠上方，这样的管子可能特别重要。最后，将开始初步研究与磁暴期间交叉尾部电流向电离层转移有关的感应电场。总体目标是研究电流如何改变近地环境。

This grant will support a study of several effects of magnetic field aligned or Birkeland electric currents. The projects begin with a standard model magnetosphere to which various Birkeland current systems will be added. The first additions will involve typical simplified auroral current systems. Then several actual current patterns which are derived from specific radar and ground magnetometer measurements will be added. The purpose of this part of the project is to study distortions in the direction and magnitude of electric fields as they are projected from the ionosphere to the outer magnetosphere in the presence of Birkeland currents. The next portion of the study involves the formation of magnetic flux tubes. These tubes are generated by perturbation magnetic fields that are driven by the Birkeland currents. Such tubes may be of special importance near the westward traveling surge of an auroral substorm, near small bright auroral spots, and over the polar caps. Finally, a preliminary study of induced electric fields that are associated with the diversion of cross tail electric currents to the ionosphere during a magnetic storm will be initiated. The overall aim is to study the way in which electric currents modify the near earth environment.