4-D modeling of CME expansion and EUV dimming observed with STEREO/EUVI
4-D modeling of CME expansion and EUV dimming observed with STEREO/EUVI
复制标题
DOI：
10.5194/angeo-27-3275-2009
复制
发表时间：
2009-08
影响因子：
1.9
通讯作者：
M. Aschwanden
中科院分区：
文献类型：
--
作者：
M. Aschwanden
这是第一次尝试模拟CME发射的运动学和由此产生的EUV调光定量与自洽模型。我们的4-D模型假设自相似膨胀的球形CME几何形状，包括一个CME前密度压缩和密度稀疏腔，满足质量守恒的总CME和扫电晕。该模型包含14个自由参数，适用于2008年3月25日STEREO/A和B观测到的CME事件。我们的模型能够再现从18：30 UT到19：00 UT的初始阶段期间观察到的CME膨胀和相关的EUV调光。CME运动学可以由恒定加速度（即，恒定的磁驱动力）。虽然EUVI/A的观测结果与球形气泡的几何形状一致，但我们发现EUVI/B存在显著的不对称性和密度不均匀性。这种新的正演模拟方法演示了如何观察到的EUV调光可以用来模拟CME源区的物理参数，CME几何形状和CME运动学。
This is the first attempt to model the kinematics of a CME launch and the resulting EUV dimming quantitatively with a self-consistent model. Our 4-D-model assumes self-similar expansion of a spherical CME geometry that consists of a CME front with density compression and a cavity with density rarefaction, satisfying mass conservation of the total CME and swept-up corona. The model contains 14 free parameters and is fitted to the 25 March 2008 CME event observed with STEREO/A and B. Our model is able to reproduce the observed CME expansion and related EUV dimming during the initial phase from 18:30 UT to 19:00 UT. The CME kinematics can be characterized by a constant acceleration (i.e., a constant magnetic driving force). While the observations of EUVI/A are consistent with a spherical bubble geometry, we detect significant asymmetries and density inhomogeneities with EUVI/B. This new forward-modeling method demonstrates how the observed EUV dimming can be used to model physical parameters of the CME source region, the CME geometry, and CME kinematics.