Active Experiments/Electric Fields

这笔拨款将支持对磁场排列或伯克兰电流的几种效应的研究。该项目从一个标准磁层模型开始，其中将添加各种伯克兰电流系统。首先增加的将包括典型的简化的极光电流系统。然后，将添加由特定雷达和地面磁力计测量得出的几种实际电流模式。该项目的这部分目的是研究在Birkeland电流存在的情况下，电场从电离层投射到外磁层时方向和强度的畸变。研究的下一部分涉及到磁通管的形成。这些管是由伯克兰电流驱动的扰动磁场产生的。在极光亚暴向西移动的涌浪附近，在明亮的小极光点附近，以及在极帽上方，这样的管道可能特别重要。最后，将开始对磁暴期间与交叉尾电流向电离层转移有关的感应电场进行初步研究。总的目标是研究电流改变近地环境的方式。

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.