Interpreting Coronagraph Data used Simulated White Light Images and 3D MHD Models of CMEs
Abstract
We use a 3D time-dependent MHD model of a CME to try to understand the relationship between the CME structure and the bright features seen in coronagraph images. Questions addressed include whether the bright leading edge seen in LASCO coronagraph images of CMEs corresponds to compressed coronal material or shocked solar wind. We will analyze the evolution of the density and magnetic field as the CME propagates for CMEs of various field strengths and initial speeds. Coronagraph line-of-sight (LOS) images show 2D projections of the 3D density structure of the CME. Synthetic coronagraph images will be computed for the various CME cases to relate the structure to the LOS images. We use the University of Michigan BATS-R-US time-dependent adaptive grid MHD code to compute the CME evolution. The CME is created by inserting a flux-rope CME into a steady-state solution for the corona. The flux rope is anchored at both ends in the photosphere and embedded in a helmet streamer; it is not initially in equilibrium. The subsequent evolution of the flux rope - its expansion and propagation through the corona to 1 AU - is computed self-consistently with the evolution of the background corona and solar wind.
- Publication:
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AAS/Solar Physics Division Meeting #34
- Pub Date:
- May 2003
- Bibcode:
- 2003SPD....34.0511L