Results from the study of an M7.6 flare and its associated CME Original Research Article

An M7.6 flare was well observed on October 24, 2003 in active region 10486 by a few instruments and satellites, including GOES, TRACE, SOHO, RHESSI and NoRH. Multi-wavelength study shows that this flare underwent two episodes. During the first episode, only a looptop source of <40 keV was observed in reconstructed RHESSI images, which showed shrinkage with a velocity of 12–14 km s−1 in a period of about 12 min. During the second process, in addition to the looptop source, two footpoint sources were observed in energy channel of as high as ∼200 keV. One of them showed fast propagation along one of the two TRACE 1600 Å flare ribbons and the 195 Å loop footpoints, which could be explained by successive magnetic reconnection. The associated CME showed a mass pickup process with decreasing center-of-mass velocity. The decrease of the CME kinetic energy and the increase of its potential energy lead to an almost constant total energy during the CME propagation. Our results reveal that the flare and its associated CME have comparable energy content, and the flare is of non-thermal property.