OBSERVING FLUX ROPE FORMATION DURING THE IMPULSIVE PHASE OF A SOLAR ERUPTION

Journal Article · Tue May 10 04:00:00 EDT 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/732/2/L25· OSTI ID:21562693

Cheng, X; Ding, M D ^[1]; Zhang, J ^[2]; Liu, Y ^[3]

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1. Department of Astronomy, Nanjing University, Nanjing 210093 (China)
2. School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Drive, MSN 6A2, Fairfax, VA 22030 (United States)
3. W. W. Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305 (United States)

Magnetic flux ropes are believed to be an important structural component of coronal mass ejections (CMEs). While there exists much observational evidence of flux ropes after the eruption, e.g., as seen in remote-sensing coronagraph images or in situ solar wind data, the direct observation of flux ropes during CME impulsive phase has been rare. In this Letter, we present an unambiguous observation of a flux rope still in the formation phase in the low corona. The CME of interest occurred above the east limb on 2010 November 3 with footpoints partially blocked. The flux rope was seen as a bright blob of hot plasma in the Atmospheric Imaging Assembly (AIA) 131 A passband (peak temperature {approx}11 MK) rising from the core of the source active region, rapidly moving outward and stretching the surrounding background magnetic field upward. The stretched magnetic field seemed to curve-in behind the core, similar to the classical magnetic reconnection scenario in eruptive flares. On the other hand, the flux rope appeared as a dark cavity in the AIA 211 A passband (2.0 MK) and 171 A passband (0.6 MK); in these relatively cool temperature bands, a bright rim clearly enclosed the dark cavity. The bright rim likely represents the pileup of the surrounding coronal plasma compressed by the expanding flux rope. The composite structure seen in AIA multiple temperature bands is very similar to that in the corresponding coronagraph images, which consists of a bright leading edge and a dark cavity, commonly believed to be a flux rope.

• OSTI ID: 21562693
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 2 Vol. 732; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ATMOSPHERES
MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETIC RECONNECTION
SOLAR ACTIVITY
SOLAR ATMOSPHERE
SOLAR CORONA
SOLAR FLARES
STELLAR ACTIVITY
STELLAR ATMOSPHERES
STELLAR CORONAE
STELLAR FLARES