On 3D Reconstruction of Coronal Mass Ejections: I. Method Description and Application to SECCHI-COR Data

The data from SECCHI-COR1 and SECCHI-COR2 coronagraphs onboard the STEREO mission, which was launched in October 2006, provide us with the first-ever stereoscopic images of the Sun’s corona. These observations were found to be useful in inferring the three-dimensional structure of coronal mass ejections (CMEs) and their propagation direction in space. We apply four methods for reconstructing CMEs: i ) Forward modeling technique; ii ) Local correlation tracking (to identify the same feature in COR Ahead and COR Behind images) plus tie-point reconstruction technique; iii ) Center of mass of the structures in a given epipolar plane plus tie-point reconstruction technique; iv ) Polarization ratio technique. The four techniques are applied to three structured CMEs observed by COR1 and COR2 instruments, respectively, on 15 May 2007, 31 August 2007, and 25 March 2008. A comparison of the results obtained from the application of the four reconstruction algorithms is presented and discussed.