内磁层电流系统动力学和能量输运

We first address the key physics of the ring current (RC), solving outstanding questions on its dynamic form (for example, the form of current closure); its composition, and its linkage both to the inner edge of the plasma sheet and into the ionosphere (via its connectivity to region 2 field aligned currents (FAC)). We then extend this study to determine the more general behaviour and form of field aligned currents (FACs); controlling part of the magnetosphere-ionosphere coupling (energy transfer), during both standard and active driving conditions (e.g. solar wind strength and IMF). Specifically, we will survey: the morphology and dynamics of the large scale region 1 (R1) and 2 (R2) current systems (separating out the effects of the R0 and NBZ FACs); the generation of small-scale and multiple current sheets; the relation of field aligned signatures to ULF waves (their Alfvénic vs stationary properties), and their impact on the ionosphere and ultimately ground currents. The study will be executed through coordinated, multi-spacecraft determination of in situ FACs and ring current densities (with other supporting properties and data), primarily from the three spacecraft Swarm; four spacecraft Cluster and MMS missions (following earlier studies using Cluster and THEMIS). We intend to map the response and the expected ring current influence (RC index) at low altitude by comparison to global magnetic field models and determine the influence from sub-storm injections. In addition to surveying in situ current densities, we will also perform statistical correlation between in situ spacecraft (to track global trends and current orientation) and statistical analysis of ground and other networks (e.g. cross-correlation and quantile analysis) of magnetometers (superMAG) and space data (AMPERE). We have a long leading heritage in analysing multi-spacecraft data, developing the related methods; have key mission roles in Swarm and Cluster, and have chaired a number of related international (ISSI) working groups.

本课题首先致力于解决环电流研究中长期悬而未决的动力学形态、成分、与等离子体片内边缘以及电离层的连接等问题。随后我们将研究场向电流的更普遍的行为和形式，以及不同太阳活动性下磁层电离层耦合过程中的能量传输。具体研究内容：1、大尺度1区、2区场向电流的形态和动力学；2、小尺度和多层电流系统；3、场向电流和ULF波的关系以及它们对电离层和地面电流的影响。本课题会通过对多卫星星座（如Swarm、Cluster和MMS）原位场向电流和环电流的观测数据以及其它辅助数据的分析来实现。我们试图将环电流的影响投影到低高度然后与地面磁场模型作比较来确定亚暴注入的影响；我们还将统计研究它们和地面（superMAG）以及其它（AMPERE）磁强计数据网络的相互关系。我们的团队在多卫星数据处理领域有丰富的经验和系统的方法；团队核心成员在Swarm和Cluster计划中担任重要角色，并且领导了多个相关的国际工作组。

关于大尺度和小尺度场向电流的尺度和动态演化研究已按计划进行。 具体来说，在空间天气的背景下独创了双轨数据相关性的比较工具（ESA ITT：Yang 等人），并且已经完成了关键的 FAC-GIC 结合研究：Wei 等人，Dong 等人。.对原位环电流及其通过场向电流与电离层的耦合研究已被推迟，直到目前有更多的共轭卫星数据可用。此工作目前还在进行中。