HR: 09:29h
AN: SH51D-04    [Abstracts]
TI: Observations of Magnetic Restructuring during the Development of Coronal Mass Ejections
AU: * PICK, M A
EM: monique.pick@obspm.fr
AF: Observatoire de Paris, LESIA, Observatoire de Meudon, Meudon, 92195 France
AU: Maia, D J
EM: dmaia@fc.up.pt
AF: Observatorio de Porto, Obs. Astronomico , Vila Nova de Gaia, 4430-146 Portugal
AB: Using a multiwavelength approach during the period 1996-2003, we investigate the different scenarios for the onset and development of Corona Mass Ejections (CMEs). We developed a daily patrol which includes the radio emission measured by the Nancay Radioheliograph and the spectra obtained by the Nancay DAM array, by WAVES aboard SOHO and by various spectrographs operating in the dm-m domain. We identify the multi loops systems that participate in the eruption process. Through this data analysis, we identify the coronal regions of magnetic field interaction leading to the restructuring of the corona and the development of CMEs. We first concentrate on about 30 fast CMEs (greater than 700 km/s) which include narrow mini-CMEs as well as wide CMEs. We show that their development result from successive sequences (even for the mini CMEs) that are associated with abrupt modifications in the radio emission and the onset of new emitting sources at positions covering some portion of the solar disk, very large in the case of wide CMEs. We secondly focuss on the study of complex type III-like events detected by WAVES at 1MHz. These events present a close association with wide CMEs. We trace the progression of these events from the low corona to the interplanetary medium. Most of the accelerated electrons originate from several distinct regions of interactions between shocks and coronal structures. We anticipate that, for this class of type III-like events which often last more than 20 minutes, distinct electron beams originating at diffent times during the progression of these events, will be measured by the two spacecrafts of the STEREO mission.
DE: 2111 Ejecta, driver gases, and magnetic clouds
DE: 2118 Energetic particles, solar
SC: SPA-Solar and Heliospheric Physics [SH]
MN: 2005 Joint Assembly