Sympathetic Eruptions of Two Filaments with an Identifiable Causal Link Observed by the Solar Dynamics Observatory

Abstract

Filament eruptions occurring at different places within a relatively short time internal, but with a certain physical causal connection are usually known as sympathetic eruption. Studies on sympathetic eruptions are not uncommon. However, in the existed reports, the causal links between sympathetic eruptions remain rather speculative. In this work, we present detailed observations of a sympathetic filament eruption event, where an identifiable causal link between two eruptive filaments is observed. On 2015 November 15, two filaments (F1 in the north and F2 in the south) were located at the southwestern quadrant of solar disk. The main axes of them were almost parallel to each other. Around 22:20 UT, F1 began to erupt, forming two flare ribbons. The southwestern ribbon apparently moved to southwest and intruded southeast part of F2. This continuous intrusion caused F2's eventual eruption. Accompanying the eruption of F2, flare ribbons and post-flare loops appeared in northwest region of F2. Meanwhile, neither flare ribbons nor post-flare loops could be observed in southeastern area of F2. In addition, the nonlinear force-free field (NLFFF) extrapolations show that the magnetic fields above F2 in the southeast region are much weaker than that in the northwest region. These results imply that the overlying magnetic fields of F2 were not uniform. So we propose that the southwest ribbon formed by eruptive F1 invaded F2 from its southeast region with relatively weaker overlying magnetic fields in comparison with its northwest region, disturbing F2 and leading F2 to erupt eventually.

Oscillations and mass-draining that lead to a sympathetic eruption of a quiescent filament

“…In Figure 7 In this paper, we report on a sympathetic filament eruption induced by a series of nearby filament eruptions. The time interval between the first and last eruption is about 8 hours, longer than those previously reported (Shen et al 2012;Song et al 2020;Hou et al 2020).…”

Sympathetic Filament Eruptions within a Fan-spine Magnetic System

“…Sympathetic filament eruptions have been studied intensively in recent years (e.g., Peng & Hu 2007;Shen et al 2012b;Song et al 2020;Hou et al 2020), and those occurred in breakout magnetic systems and pseudostreamers often started from external reconnection around the null point due to external or internal disturbances (e.g., Moore et al 2001;Peng & Hu 2007;Shen et al 2012b;Török et al 2011;Lynch & Edmondson 2013). In principle, if the external reconnection starts first, it will greatly consume the overlying confining magnetic field lines and decrease the magnetic tension force upon the low-lying core magnetic structure such as a filament.…”

“…Hou et al (2020) investigated the consecutive eruption of two nearby filaments, in which the authors found that the first filament eruption pushed its overlying loops to reconnect with the overlying loop of the other filament. Therefore, the filament became unstable and then erupted due to the reduction of the overlying magnetic fields by the external magnetic reconnection (Song et al 2020). Shen et al (2012b) reported two consecutive filament eruptions in a breakout magnetic configuration, including a partial filament eruption and a full successful filament eruption.…”

Quiet-Filament Eruptions and Coronal Jets as Causes of Depressions in Microwave Radio Emission

“…The rise and expansion of the filament was observed from 21:30 both in the H line (e.g., in MLSO images) and in extrime ultraviolet channels in SDO/AIA images. A possible cause of eruption is the emergence and cancellation of magnetic flux of opposite polarity, which occurred in several places along the neutral line of the magnetic field [13,14]. The eruption was accompanied by flare-like ribbons visible in the EUV and a slowing coronal mass ejection (CME).…”