Numerical Modeling of Flare-productive Active Regions of the Sun
Abstract
It is known that strong flare events on the Sun take place in active regions (ARs), especially in delta sunspots with closely-packed positive and negative polarities. The delta spots are produced as a result of complex magnetic flux emergence and have strong-field, highly-sheared polarity inversion lines (PILs). Here we report on the numerical simulations of four types of such flare-productive ARs, namely, (1) Spot-Spot, a complex AR with AR-sized PIL, (2) Spot-Satellite, in which a newly-emerging bipole appears next to the pre-existing sunspot, (3) Quadrupole, where two emerging bipoles collide against each other, and (4) Inter-AR, the flares occurring between two separated ARs. We reproduced these four cases by conducting a series of 3D MHD flux emergence simulations and found, for example, that the sheared PILs in these ARs are created through the stretching and advection of horizontal magnetic fields due to relative spot motions. As ARs develop, free magnetic energy becomes stored in the corona, which could be eventually released through flare eruptions. In the presentation, we also mention the relationship between the HMI/SHARP parameters measured in the photosphere and the free energy stored in the corona, and discuss why these parameters successfully predict the flares.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2017
- Bibcode:
- 2017AGUFMSH43C..07T
- Keywords:
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- 7514 Energetic particles;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY;
- 7519 Flares;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY;
- 7524 Magnetic fields;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY;
- 7554 X-rays;
- gamma rays;
- and neutrinos;
- SOLAR PHYSICS;
- ASTROPHYSICS;
- AND ASTRONOMY