Formation, Interaction and Merger of an Active Region and a Quiescent Filament Prior to Their Eruption on 19 May 2007

Abstract

We report observations of the formation of two filaments -one active and one quiescent, and their subsequent interactions prior to eruption. The active region filament appeared on 17 May 2007, followed by the quiescent filament about 24 hours later. In the 26 hour interval preceding the eruption, which occurred at around 12:50 UT on 19 May 2007, we see the two filaments attempting to merge and filament material is repeatedly heated suggesting magnetic reconnection. The filament structure is observed to become increasingly dynamic preceding the eruption with two small hard X-ray sources seen close to the active part of the filament at around 01:38 UT on 19 May 2007 during one of the activity episodes. The final eruption on 19 May at about 12:51 UT involves a complex CME structure, a flare and a coronal wave. A magnetic cloud is observed near Earth by the STEREO-B and WIND spacecraft about 2.7 days later. Here we describe the behaviour of the two filaments in the period prior to the eruption and assess the nature of their dynamic interactions.

Evidence for magnetic flux cancelation leading to an ejective solar eruption observed byHinode,TRACE,STEREO, andSoHO/MDI

“…An obvious eruption to consider is one that occurred in the same active region, but on the previous day, on 2007 May 19 starting near 12:00 UT. That event was analyzed by Li et al (2008), Liewer et al (2009) and Bone et al (2009), while Veronig et al (2008) focused on a coronal wave generated from that eruption. Alas however, those workers show that the May 19 event mainly occurred on a different PIL from the May 20 event of this paper, with the primary filament of the May 19 event located in the PIL west of that of the May 20 event (see in particular Bone et al 2009).…”

Stereoscopic Analysis of the 19 May 2007 Erupting Filament

“…The behavior of the filament during this period is analyzed using additional data from Hinode and other ground-based Hα observatories in Bone et al (2009). Moreover, this point may not be the highest point on the filament because not all portions of the filament could be tiepointed at each time due to foreground and/or background confusion.…”

“…Because of this close association with CMEs and the importance of CMEs in space weather, understanding the processes involved in filament eruptions continues to be an active area of research (see, for example, Tonooka et al, 2000;Moore, Sterling, and Suess, 2007;Sterling et al, 2007;Lites, 2008;Lin et al, 2008); a better understanding of prominence eruptions may well lead to a better ability to forecast CMEs and associated space eruption was associated with a B9.5 flare, coronal dimming, an EUVI wave, and a double CME (Li et al, 2008;Kilpua et al, 2009;Veronig, Temmer, and Vrsnak, 2008). The evolution of the filament prior to the eruption has been studied by Bone et al (2009)…”

Interaction of Two Filament Channels of Different Chiralities

“…The merging of two filament channels after dynamic interactions has also been observed by Schmieder et al (2004), Bone et al (2009), Jiang et al (2014a, and Joshi et al (2014a). Schmieder et al (2004) found evidence of a merging of two segments with dextral chiralities to form a long dextral filament.…”

“…Filaments exist in the magnetic dips within magnetic configurations known as filament channels or flux ropes (Aulanier et al 2002;Liu et al 2012). Filaments and/or associated channels sometimes interact and show interesting dynamics in the chromosphere and low corona (Uralov et al 2002;Schmieder et al 2004;Su et al 2007;Bone et al 2009;Kumar et al 2010;Liu et al 2010;Chandra et al 2011;Filippov 2011;Li & Ding 2012;Jiang et al 2013Jiang et al , 2014Joshi et al 2014a). During an interaction under specific conditions, these magnetic structures can reconnect and change their footpoint connectivity.…”