Study of 3-dimensional structure of coronal mass ejections in the interplanetary space

1.通过对日冕物质抛射观测的模型拟合分析确定日冕物质抛射的三维(3D)结构从对日冕物质抛射事件进行的STEL IPS观测中反演了与日冕物质抛射有关的密度增强的三维分布，这对地球磁层产生了重大影响。对于一些事件，揭示了具有各向同性角度范围的壳状结构，而对于其他事件，揭示了沿给定n方向伸长的环状结构。通过与航天器观测的比较，我们发现这些特征要么对应于与激波相关的压缩区域，要么对应于CME内的日冕抛射。2.利用宇宙线调制观测分析大尺度磁结构利用宇宙线调制观测推导出与CME相关的圆柱形磁场结构，并与STEL IPS观测得到的环状高密度结构进行了比较。结果，我们发现他们之间存在着普遍的共识。3.利用SMEI(太阳质量抛射成像仪)和IPS资料分析了环状高密度结构的三维结构。2003年10月28日CM E事件由STEL IPS观测得到的高密度区的三维分布与SMEI同时观测的三维密度重建结果一致。S认为，由于两次观测发现的环状密度结构的传播速度都比磁通绳慢，因此认为它的起源是被限制在磁绳内的日冕抛射物。

1.Determination of 3-dimensional(3D)structure of CMEs by the model fitting analysis of IPS observationsThe 3D distribution of density enhancements associated with CMEs was retrieved from STEL IPS observations for CME events, which produced significant influences on the Earth's magnetosphere. A shell-shaped structure with an isotropic angular extent was revealed for some of the events, and a loop structure elongating in a give n direction was disclosed for other events. From comparison with spacecraft observations, we found that these features corresponded to either the compression region associated with the shock or the coronal ejecta within the CME.2.Analysis of large-scale magnetic structure using cosmic ray modulation observationsThe CME-associated cylindrical structure of the magnetic field deduced from cosmic ray observations of the Sh inshu University was compared with the loop-shaped high density structure determined from STEL IPS observat ions. As result, we found that there was general agreement between them. This fact suggests that the magneti c flux plays an important role in formation of the loop-shaped high density structure.3.Analysis of 3D structure using SMEI (Solar Mass Ejection Imager) and IPS dataThe 3D distribution of high density region retrieved from STEL IPS observations for the 2003 October 28 CM E event was found to be consistent with 3D density reconstruction from simultaneous observations by SMEI. S ince the loop-shaped density structure identified from both observations propagated at slower speed than the sh ock, its origin was considered to be the coronal ejecta confined within the magnetic flux rope.