Energization and Disruption of Magnetic Arcades in the Solar Corona

日冕物质抛射（CME）是太阳活动的壮观表现。日冕物质抛射到太阳风中的等离子体和磁通量随后与地球磁场相互作用，产生地磁扰动。计划研究CME的可能启动机制。这将允许检验假设CME和耀斑是单一事件的辐射，是整体磁结构的理想或电阻不稳定性。该研究将围绕全球日冕场结构（单个和多个拱廊，以及头盔飘带结构）在剪切光球运动下的动态演变进行研究。日冕的行为将使用时间相关磁流体动力学（MHD）模拟来模拟。日冕场的全球演化将自洽地遵循球面几何，在几个太阳半径上响应于光球层的运动。等离子体密度和速度的演化结果将与现有的CME观测结果进行比较。将采用半隐式方法，以便有效地计算日冕磁场中缓慢的能量积累。最初，将使用2维（轴对称）描述，随后将开发3维模拟和描述。

Coronal mass ejections (CME's) provide a spectacular manifestation of solar activity. The plasma and magnetic flux ejected into the solar wind by CME's subsequently interacts with the Earth's magnetic field to produce geomagnetic disturbances. It is planned to investigate possible initiation mechanisms for CME's. This will permit examination of the hypothesis that CME's and flares are minefistations of a single event, an ideal or resistive instability of the overall magnetic configuration. The investigation will center around a study of the dynamical evolution of global coronal field structures (single and multiple arcades, as well as helmet streamer configurations) in response to shearing photospheric motions. The behavior of the corona will be modelled using time dependent magnetohydrodynamic (MHD) simulations. The global evolution of the coronal field will be followed self-consistently in spherical geometry over several solar radii in response to motions applied at the photosphere. The resulting evolution of the plasma density and velocity will be compared to available CME observations. Semi-implicit methods will be employed to allow for efficient computation of slow energy build-up in the coronal magnetic fields. Initially, a 2- dimensional (axisymmetrical) description will be used, followed by development of a 3-dimensional simulation and description.