Understanding Conjugacy and Non-conjugacy of the Auroral Electrojet System

本项目将研究极光电喷流系统的磁共轭和非共轭。非共轭行为的实例可能由四个不同原因中的一个或多个引起。非共轭行为的可能原因是：(1)地球内部磁场的半球间差异，(2)由于太阳照度的差异而导致的电离层电导率的差异，(3)由行星际磁场(IMF)驱动的外部电流，以及(4)从一个半球流向另一个半球的场向电流。将使用对大量事件的统计分析来确定非共轭行为的每个可能原因在什么条件下是可操作的。该项目将描述两个半球极光电喷流系统的不同和相似之处，并将确定对季节、地点和货币基金组织条件的依赖。我们对极光现象行为的大部分知识来自对北半球的观察，通常的假设是，南半球只是北半球发生的事情的一面镜子。两个位置，一个在北半球，一个在南半球，如果它们通过磁力线相连，则称为共轭。在两个半球同时进行的光学观测显示了许多非共轭行为的例子。这个项目将使用从大量磁力计在两个半球获得的磁场测量来检查产生非共轭行为的条件。

This project will examine the magnetic conjugacy and non-conjugacy of the auroral electrojet system. Instances of non-conjugate behavior may arise from one or more of four different reasons. The possible reasons for non-conjugate behavior are: (1) inter-hemispherical differences in Earth's internal magnetic field, (2) differences in ionospheric conductivity due to differences in solar illumination, (3) external electric currents driven by the interplanetary magnetic field (IMF) and (4) field-aligned currents flowing from one hemisphere to the other. Statistical analyses of a large number of events will be used to determine under what conditions each of the possible reasons for non-conjugate behavior are operative. The project will characterize differences and similarities in the auroral electrojet systems in the two hemispheres and will determine the dependence on season, location and IMF conditions. Most of our knowledge of the behavior of auroral phenomena comes from observations in the northern hemisphere and the common assumption is that the southern hemisphere is simply a mirror of what happens in the northern hemisphere. Two locations, one in the northern hemisphere and one in the southern hemisphere are referred to a conjugate if they are connected by a magnetic field line. Optical observations done simultaneously in both hemispheres has shown many instances of non-conjugate behavior. This project will use magnetic field measurements taken in both hemispheres from a large number of magnetometers to examine the conditions that produce non-conjugate behavior.