Modeling the Effects of Magnetic Field Variation on Solar Flares

Advisor: John Unverferth, Dana Longcope

Solar flares occur when a large amount of energy is converted into X-rays, heat and supersonic fluid motion. Prior to the flare this energy is stored in a magnetic field filling the atmosphere above sunspots and related features called active regions. The energy is released suddenly when an electric field changes the connectivity of several coronal magnetic field lines. A single change of this kind permits the newly configured magnetic field line to retract rapidly, releasing energy exactly as would a rubber band under tension. The physics governing the retraction of the reconnected field line is almost exactly the same as those of an elastic string.

The student will work with computer code that solves the dynamics of a retracting flux tube with variable magnetic field strength. Using the results of this code the student will attempt to match observed hot loop-top sources of soft X-ray emission to simulations. Electromagnetism is essential, and knowledge of both computer programming and fluid dynamics would be useful.