Simulation of magnetic flux rope (twisted fieldlines) emerging through solar photosphere (green plane) into an overlying coronal arcade (high, arching fieldlines). Fieldlines from  the emerging rope rise into the corona and reconnect with the overlying field to form an unstable, coronal rope. Ongoing work: Can this coronal rope be made sufficiently robust and unstable that it will form an erupting CME?  Leake & Linton (NRL)
Simulation of magnetic flux rope (twisted fieldlines) emerging through solar photosphere (green plane) into an overlying coronal arcade (high, arching fieldlines). Fieldlines from the emerging rope rise into the corona and reconnect with the overlying field to form an unstable, coronal rope. Ongoing work: Can this coronal rope be made sufficiently robust and unstable that it will form an erupting CME? Leake & Linton (NRL)

Objectives

  • Drive Coronal Mass Ejection (CME) eruptions by self-consistently emerging convection zone magnetic field into pre-existing, coronal magnetic field configurations. Test validity of current CME models.
  • Improve our understanding of how CMEs are driven or destabilized. Enhance the Navy’s ability to develop predictive tools for these solar eruptions and their space weather consequences, by determining how current observations of flux emergence can be incorporated into CME prediction models.

Approach

  • Perform HPC simulations of the dynamic emergence from the solar convection zone into the corona of magnetic flux systems
  • Use this flux emergence to test current CME models, in particular the “breakout,” “torus instability” and “flux cancelation” models
  • Determine the viability of these eruptions when driven by self-consistent flux emergence rather than by the kinematic lower boundary (“photospheric”) motions currently used in these models
  • Compare the morphology and dynamics of the resulting coronal magnetic field structures and CMEs with STEREO, Hinode, and SDO observations

Deliverable/Value/Accomplishment

  • Determined that flux emergence is not effective driver of breakout CMEs in two dimensions, as dense plasma is carried up into corona and weighs down coronal flux rope
  • Showed that flux emergence is significantly more effective in three dimensions (3D), as the extra mass can drain along the emerging fieldlines
  • Current work: increase flux in erupting coronal field in 3D simulations so that field can erupt as a full breakout CME
  • Future work: study flux emergence mechanism for alternate CME models (torus, flux cancellation)