Disappearances of High-Latitude Filaments as Sources of High-Latitude CMEs

Abstract

AbstractFrom a statistical comparison of high-latitude coronal mass ejections (CMEs) and disappearing solar filaments (DSFs), we find: (1) Beginning with the “rush to the poles”, DSFs arise at an increasing rate from the “emerging” or polar crown relative to the “true” polar crown. At maximum, these “opposite polarity” filaments are the dominant source of high-latitude DSFs. Following polarity reversal, the emergent polar crown becomes the true polar crown and the source of virtually all highlatitude DSFs. (2) At the last two solar maxima, we estimate that there were ~ 4 times as many high-latitude (≥ 60°) CMEs as high-latitude (≥ 45°) DSFs. Possible reasons for this discrepancy include the following: (a) DSFs, particularly small ones, are under-reported, (b) propagation effects, whereby radially propagating CMEs appear at higher latitudes than their underlying source regions, are more important than currently thought, or (c) some combination of these effects.