Solar explosive events such as flares and coronal mass ejections (CMEs) are believed to be driven by the free magnetic energy stored in the current carrying (twisted) coronal magnetic fields. However, the basic underlying magnetic field structure for CME precursors and the initiation mechanisms f... Show moreSolar explosive events such as flares and coronal mass ejections (CMEs) are believed to be driven by the free magnetic energy stored in the current carrying (twisted) coronal magnetic fields. However, the basic underlying magnetic field structure for CME precursors and the initiation mechanisms for their sudden eruption remain fundamental unanswered questions under investigation. In this talk I present 3D MHD simulations of the loss of of confinement and eruption of a twisted magnetic flux rope emerging quasi-statically into a pre-existing coronal arcade field. It is found that the flux rope can erupt through either the onset of the torus instability or the kink instability. In the former case the erupting flux rope primarily shows an outward expansion at the onset of eruption while in the latter case the flux rope develops large writhe or rotation. I will discuss the implications of the model results and show how they provide explanations for a range of CME-related observations. Show less
