TY - JOUR
T1 - THEMIS, BBSO, MDI and TRACE observations of a filament eruption
AU - Contarino, L.
AU - Romano, P.
AU - Yurchyshyn, Vasyl
AU - Zuccarello, F.
N1 - Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2003/9
Y1 - 2003/9
N2 - We describe a filament destabilization which occurred on 5 May 2001 in NOAA AR 9445, before a flare event. The analysis is based on Hα data acquired by THEMIS operating in IPM mode, Hα data and magnetograms obtained at the Big Bear Solar Observatory, MDI magnetograms and 171 Å images taken by TRACE. Observations at 171 Å show that ∼ 2.5 hours before the flare peak, the western part of the EUY filament channel seems to split into two parts. The bifurcation of the filament in the Hα line is observed to take place ∼ 1.5 hours before the flare peak, while one thread of the filament erupts ∼10 min before the peak of the flare. Our analysis of longitudinal magnetograms shows the presence of a knot of positive flux inside a region of negative polarity, which coincides with the site of filament bifurcation. We interpret this event as occurring in two steps: the first step, characterized by the appearance of a new magnetic feature and the successive reconnection in the lower atmosphere between its field lines and the field lines of the old arcade sustaining the filament, leads to a new filament channel and to the observed filament bifurcation; the second step, characterized by the eruption of part of the filament lying on the old PIL, leads to a second reconnection, occurring higher in the corona.
AB - We describe a filament destabilization which occurred on 5 May 2001 in NOAA AR 9445, before a flare event. The analysis is based on Hα data acquired by THEMIS operating in IPM mode, Hα data and magnetograms obtained at the Big Bear Solar Observatory, MDI magnetograms and 171 Å images taken by TRACE. Observations at 171 Å show that ∼ 2.5 hours before the flare peak, the western part of the EUY filament channel seems to split into two parts. The bifurcation of the filament in the Hα line is observed to take place ∼ 1.5 hours before the flare peak, while one thread of the filament erupts ∼10 min before the peak of the flare. Our analysis of longitudinal magnetograms shows the presence of a knot of positive flux inside a region of negative polarity, which coincides with the site of filament bifurcation. We interpret this event as occurring in two steps: the first step, characterized by the appearance of a new magnetic feature and the successive reconnection in the lower atmosphere between its field lines and the field lines of the old arcade sustaining the filament, leads to a new filament channel and to the observed filament bifurcation; the second step, characterized by the eruption of part of the filament lying on the old PIL, leads to a second reconnection, occurring higher in the corona.
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U2 - 10.1023/A:1026107727149
DO - 10.1023/A:1026107727149
M3 - Article
AN - SCOPUS:0347753415
VL - 216
SP - 173
EP - 188
JO - Solar Physics
JF - Solar Physics
SN - 0038-0938
IS - 1-2
ER -