[Previous] | [Session 2] | [Next]
D.M. Zarro (SM&A/GSFC), R.C. Canfield (MSU/Bozeman), N. Nitta (LMSAL), D.C. Myers (SM&A/GSFC), S.E. Gregory (Stanford), J. Qiu (BBSO), D. Alexander (LMSAL), H.S. Hudson (ISAS/SPRC), B.J. Thompson (NASA/GSFC), B.J. LaBonte (Mees/IFA)
We report on observations of a sigmoidal region AR~8668 obtained during the Whole Sun Month~#3 campaign and Max Millennium Coordinated Observing Program~#2. The observations pertain to the period 1999~August 16-17 during which several GOES B and C class flares occurred in AR~8668. Near simultaneous observations were obtained by SOHO (EIT~195~Å\/ and MDI full-disk magnetograms), TRACE~171~Å\/, Yohkoh~SXT, Big Bear (H\alpha), and Mees (IVM vector magnetograms). The multi-wavelength nature of these data, combined with their overlapping spatial and temporal coverages, provide a unique opportunity to study the magnetic topology and flaring evolution of twisted flux structures associated with sigmoids. An objective of this study is to co-align images and magnetograms obtained before and during the observed flares, and compare the results with inferences from the topological model of Titov and Demoulin, A&A 351, 707 (1999). We will present examples of these coalignments and identify sites of magnetic energy release that are associated with topological features (e.g. separatrices) predicted by this model.