Magnetic structures and energy of 1989 March flares

We use a recently developed non-linear force-free model to analyze the magnetic structures and energy for 1989 March flares. In this analysis, we extrapolated the magnetic structure using the vector magnetograms obtained at Huairou Solar Observatory. In order to validate our extrapolated magnetic field topology, we compared our computed magnetic field results with Hα pictures obtained at Big Bear Solar Observatory. The results are presented for the evolution of the magnetic field structure (i.e. potential and non-linear force-free field), magnetic energy, and current distribution. It shows that the location of the occurrences of the flares are approximately related to the location of the high intensity of the currents. Further, we demonstrate that the amount of energy in force-free fields is more than adequate to power the flares.