Erupting Prominences and the Geometry of Coronal Mass Ejections

摘要

Studies of the origins of coronal mass ejections (CMEs) show a strong association between CMEs and erupting prominences. Loop CMEs form the most common morphological class for both Skylab and Solar Maximum Mission (SMM) and the class most likely to be associated with erupting prominences. In the optically thin corona the geometry of such structures is interpreted as either planar (two-dimensional) or shell-like or bubblelike (three-dimensional) structures. Trottet and MacQueen (1980) (hereinafter referred to as TM) first examined the orientations of prominences associated with Skylab CMEs and argued that looplike CMEs were planar structures in the plane of the sky. Following TM, I measured the initial orientations of prominences identified with SMM CMEs in 1980 in order to examine the overall geometry of CMEs. Contrary to TM's result, I found no preferred orientation for prominences associated with SMM CMEs nor any difference between that population and the population of all disk filaments. In addition, plots comparing CME/filament orientation angles and the angular widths of the CME envelopes show large scatter. Taken together, these results support a shell-like rather than a planar geometry for at least looplike CMEs. Keywords: Coronal mass ejections; Erupting prominences; Reprints. (jhd)