http://arxiv.org/abs/1908.08650
Coronal mass ejections (CMEs) play a decisive role in driving space weather, especially, the fast ones (e.g., with speeds above $800$~km~s$^{-1}$). Understanding the trigger mechanisms of fast CMEs can help us gaining important information in forecasting them. The filament eruptions accompanied with CMEs provide a good tracer in studying the early evolution of CMEs. Here we surveyed 66 filament-accompanied fast CMEs to analyse the correlation between the trigger mechanisms, namely either magnetic reconnection or ideal MHD process, associated flares, and CME speeds. Based on the data gathering from SDO, GONG and STEREO, we find that: (1) Active region (AR) filament and intermediate filaments (IFs) eruptions show a higher probability for producing fast CMEs than quiet Sun (QS) filaments, while the probability of polar crown (PC) filament eruptions is zero in our statistic; (2) AR filament eruptions that produce fast CMEs are more likely triggered by magnetic reconnection, while QS and IFs are more likely triggered by ideal MHD process; (3) For AR filaments and IFs, it seems that the specific trigger mechanism does not have a significant influence on the resulted CME speeds, while for the QS filaments, the ideal MHD mechanism can more likely generate a faster CME; (4) Comparing with previous statistic study, the onset heights of filament eruptions and the decay indexes of the overlying field show some differences: for AR filaments and IFs, the decay indexes are larger and much closer to the theoretical threshold, while for QS filaments, the onset heights are higher than those obtained in previous results.
P. Zou, C. Jiang, F. Wei, et. al.
Mon, 26 Aug 19
5/55
Comments: 16 pages, 9 figures, accept by ApJ