HR: 14:10h
AN: SM13C-02    [Abstracts]
TI: Feedback Excitation of Double Reconnection as a Mechanism of the Impulsive Onset of Solar Flares
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: Maeshiro, T
EM: cddhm662@ybb.ne.jp
AF: Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, 739-8530 Japan
AU: Yokoyama, T
EM: yokoyama.t@eps.s.u-tokyo.ac.jp
AF: Department of Earth & Planetary Science, University of Tokyo, 7-3-1, Hongo, Bunkyou-ku, Tokyo, 113-0033 Japan
AU: Sakurai, T
EM: sakurai@solar.mtk.nao.ac.jp
AF: National Astronomical Observatory, 2-21-1 Osawa, Mitaka, Tokyo, 181-8588 Japan
AB: The impulsive onset mechanism of solar flares is one of the long-standing problems, which are not yet well understood. In order to shed light on it, we study the nonlinear dynamics of the resistive tearing mode instability growing on a thin current sheet, where the magnetic shear of coronal magnetic arcade is steeply reversed, using the high-resolution three-dimensional magnetohydrodynamic simulations. The simulation indicates that the eruption of magnetic arcade suddenly arises in the nonlinear phase of the instability. The mechanism of the impulsive onset of the eruption can be explained by the feedback excitation of double reconnection, one of which corresponds to the original tearing reconnection but the another is driven by the collapsing of magnetic arcade caused by the former reconnection. Based on the results, a new model of solar flare onset is proposed. The consistency between the model and the observation is examined by the correlation analysis between the vector magnetograms and the ultra-violet image of solar flares observed by the TRACE satellite. The underlying physics of the double reconnection is also discussed from the view point of resemblance with the nonlinear excitation of double tearing mode instability in tokamak plasma.
DE: 7509 Corona
DE: 7519 Flares
DE: 7526 Magnetic reconnection (2723, 7835)
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005