First Determination of 2D Speed Distribution within the Bodies of Coronal Mass Ejections with Cross-correlation Analysis

2019

The determination of the speed of Coronal Mass Ejections (CMEs) is usually done by tracking brighter features (such as the CME front and core) in visible light coronagraphic images and by deriving unidimensional profiles of the CME speed as a function of altitude or time. Nevertheless, CMEs are usually characterized by the presence of significant density inhomogeneities propagating outward with different radial and latitudinal projected speeds, resulting in a complex evolution eventually forming the Interplanetary CME. In this work, we demonstrate for the first time how coronagraphic image sequences can be analyzed with cross-correlation technique to derive 2D maps of the almost instantaneo…