HR: 0800h
AN: NG21A-0202 INVITED    [Abstracts]
TI: Magnetohydrodynamic Relaxation Processes in the Solar Corona
AU: * Kusano, K
EM: kusano@jamstec.go.jp
AF: The Earth Simulator Center, JAMSTEC, 3173-25 Showa-machi, Kanazawa-ku, Yokohama, 236-0001, Japan
AU: Inoue, S
EM: inosato@stelab.nagoya-u.ac.jp
AF: STEL, Nagoya Univ., Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan
AB: The magnetohydrodynamic (MHD) relaxation model, which was originally developed by J.B.Taylor, provided us a basic framework to understand the spontaneous formation and the transition of characteristic structures in MHD plasmas of low-beta and high-magnetic Reynolds number. The observation and numerical simulations have suggested that the Taylor-type relaxation could be operated not only in laboratory plasma but also in the solar corona, and may play a crucial role to form the typical large-scale helical structure, so-called sigmoid, in solar coronal active regions. However, the recent sophisticated data analysis indicated that magnetic shear parameter alpha, which is defined by the ratio between magnetic field and the curl of that, is highly distributed within an active region. It implies that the solar corona is far complicated than the theoretical model, and we cannot straightforwardly apply the simple relaxation model, which predict that the linear force-free field must be self-organized, to the solar coronal plasma. In this paper, first, we review the previous studies of the relaxation processes in the solar corona, and, second, represent the results of our recent works based on the reconstruction analysis of the three-dimensional magnetic field of active region using the high-accurate vector magnetogram observed by the Solar Optical Telescope (SOT) boarded on Hinode satellite. The results indicate that the relaxation scenario may be applicable, even though the magnetic field in flaring region is more complicated than previous thought. Finally, let us explain our recent effort to reproduce the flaring dynamics using the high-resolution numerical simulation driven by the real data. The comparative study between the simulation and the relaxation theory will be also represented.
DE: 7500 SOLAR PHYSICS, ASTROPHYSICS, AND ASTRONOMY
DE: 7519 Flares
DE: 7524 Magnetic fields
DE: 7839 Nonlinear phenomena (4400, 6944)
SC: Nonlinear Geophysics [NG]
MN: 2007 Fall Meeting