Poster abstract

We have studied an X3.8 flare occurred in NOAA 10720. We have analyzed Hα images acquired at INAF - Catania Astrophysical Observatory, TRACE images acquired at 1600 Å, full disk MDI magnetograms, RHESSI hard X-ray data and Ondrejov radio data in order to investigate the morphological and magnetic evolution of the active region before and during the flare. The data used indicate that the peak of the flare was preceded by two previous peaks in the soft X-ray range, as recorded by the GOES satellite. Moreover, two impulsive halo CMEs were detected by LASCO C2 during the flare. The analysis of these data allowed us to interpret this event as due to a sequence of destabilizing processes, in a sort of domino effect (Zuccarello et al., 2009).

F. Zuccarello, P. Romano, F. Farnik, M. Karlicky, L. Contarino, V. Battiato, S.L. Guglielmino, M. Comparato, I. Ugarte-Urra, The X17.2 flare occurred in NOAA 10486: an example of filament destabilization caused by a domino effect, A&A, 493, 629, 2009