Mapping the whole of auroral regions onto the magnetosphere

这个项目的目标是提出一种映射方法，使我们能够将整个极光区域映射到磁层上。通常的制图方法利用磁场线模型，即在磁层中观测到的磁场的平均值。这种方法在将高纬度极光区域映射到磁尾（bbb10re）时不是很可靠，因为磁尾中的磁场包含很大的波动。在本研究中，我们提出了另一种不使用任何场线模型的制图方法。在我们的方法中，粒子结构被用作描绘极光区域到磁层的示踪剂。(1) 2004年，对akakebono卫星在极光区和Geotail卫星在磁尾区获得的粒子数据进行了分析。我们发现了两种粒子结构。在极光区和磁层区都发现了这些结构。(2)在这些结果的基础上，我们提出了一种利用粒子结构作为示踪剂的新的制图方法（场线示踪）。论文3和4表明，这种方法也适用于高纬度极光制图。因此，我们成功地提出了一种新的映射方法。然而，我们的方法只能在地磁安静条件下成功地绘制极光区域。为了完成我们的模型，计划对在活动条件下获得的粒子数据进行更详细的分析。这是我们研究的下一步。

The goal of this project is to present a mapping method which enables us to map the whole of auroral regions onto the magnetosphere. Usual methods of mapping utilize field-line models that are the average of the magnetic field observed in the magnetosphere. This method is not very reliable in mapping high-latitude auroral regions to the magnetotail (>10 Re), since the magnetic field in the magnetotail includes large fluctuations. In this study, we proposed another method for mapping, in which any field-line models are not used. In our method, particle structures are utilized as tracers for mapping auroral regions to the magnetosphere.(1)In 2004, we analyzed the particle data obtained by the Akebono satellite in the auroral regions and by the Geotail satellite in the magnetotail. We found two kinds of particle structures. These structures were identified both in the auroral and magnetospheric regions. It was expected that they can be utilized as tracers for mapping (Paper 1 and 2).(2)On the basis of these results, we proposed a new method of mapping (field-line tracing) in which we utilize the particle structures as tracers. It was shown (in Paper 3 and 4) that this method is applicable also to the case of high-latitude aurora mapping.Thus, we have succeeded in presenting a new method for mapping. However, our method is successful only in mapping auroral regions observed under the geomagnetically quiet condition. More detailed analysis of particle data obtained under active conditions is planned for completing our model. This is the next step in our study.