The evolution of vector photospheric magnetic fields has been studied in concert with photospheric spot motions for a flare-productive active region. Over a three-day period (5-7 April, 1980), sheared photospheric velocity fields inferred from spot motions are compared both with changes in the orien
Modeling of energy buildup for a flare-productive region
โ Scribed by S. T. Wu; Y. Q. Hu; K. R. Krall; M. J. Hagyard; J. B. Smith
- Publisher
- Springer
- Year
- 1984
- Tongue
- English
- Weight
- 825 KB
- Volume
- 90
- Category
- Article
- ISSN
- 0038-0938
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โฆ Synopsis
A self-consistent magnetohydrodynamic MHD) model of shearing magnetic loops is used to investigate magnetic energy buildup in active region AR 2372 (Boulder number), in the period of 5-7 April, 1980. The magnetic field and sunspot motions in this region, derived using observational data obtained by the Marshall Space Flight Center Solar Observatory, suggest the initial boundary conditions for the model. It is found that the plasma parameters (i.e., density, temperature, and plasma flow velocity) do not change appreciable during the process of energy buildup as the magnetic loops are sheared. Thus, almost all of the added energy is stored in the magnetic field. Furthermore, it is shown that dynamical processes are not important during a slow buildup (i.e., for a shearing velocity less than 1 km s -1). Finally, we conclude that the amount of magnetic energy stored and the location of this stored magnetic energy depend on the initial magnetic field (whether potential of sheared) and the magnitude of the shearing motion.
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