Two types of flare-associated coronal mass ejections
Astronomical Observatory of Jagiellonian University, Cracow, Poland e-mail: email@example.com
Accepted: 15 October 2008
Aims. Here, we study the relationship between flares and CMEs.
Methods. For this purpose a statistical analysis of 578 flare-associated CMEs is presented. We considered two types of flare-associated CMEs: CMEs that follow and precede flare onset.
Results. We shown that both samples have quite different characteristics. The first type of CMEs tends to be decelerated (median acceleration = –5.0 m s-2), faster (median velocity = 519 km s-1), and physically related to flares (a correlation coefficient between the energy of the CME and the peak of the X-ray flare = 0.80). The CMEs preceding associated flares are mostly accelerated (median acceleration = 5.4 m s-2), slightly slower (median velocity = 487 km s-1), and poorly related to flares (a correlation coefficient between the energy of the CME and the peak of the X-ray flare = 0.12).
Conclusions. These two types of flare-associated CMEs demonstrate that magnetic reconnection, which influences the CME acceleration, could be significantly different in the two types of events.
Key words: Sun: coronal mass ejections (CMEs) / Sun: flares
© ESO, 2009