Gwangson Choe (Kyung Hee University, Yongin, Korea)

Energetics and Dynamics of Large Scale Solar Eruptions
When Oct 04, 2012 from 11:00 AM to 12:00 PM
What
  • Special Seminar
Where SH, Lecture hall
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Coronal mass ejections involve expulsion of mass and magnetic flux and stretching of field lines into the interplanetary space. The time scale of an eruption is much shorter than the time scale of energy buildup and the life span of structures to erupt such as prominences. Thus, the eruption is regarded as a spontaneous process rather than a simultaneously driven process. The pre-eruption stage is considered as a meta-stable state having more energy than all the states appearing in the course of the eruption, one of which is the open field state. The trigger of the eruption just plays the role of pushing the system into lower energy states. This talk illuminates two issues: (1) how a configuration with more magnetic energy than the open field can arise, and (2) how a coronal magnetic field system evolves from a mere gathering of small scale flux tubes into an eruption-vulnerable high energy meta-stable state of a large scale and finally moves into eruption. Our attention is focused on statics and dynamics multiple flux systems since we have found that such systems can have more energy than open fields. Our study reveals that a multiple flux system under a line-tying condition evolves stepwise through different multiple flux systems toward eruption. An observational example for our model will also be presented.