Observations of simultaneous coronal loop shrinkage and expansion during the decay phase of a solar flare
Abstract
We report what we believe are the first direct and unambiguous observations of simultaneous coronal magnetic flux loop shrinkage and expansion during the decay phase of a solar flare. The retracting and expanding loops were observed nearly face-on (i.e., with the loop major axis approximately orthogonal to the line of sight) in emission in imaging data from the Yohkoh Soft X-ray Telescope (SXT). The retracting loop is observed to shrink with a speed of 118 ± 66 km s-1. The faint outward moving loop-like feature occurred ~200´´ above the shrinking loop during the time of the shrinking loop. We estimate the speed of the outward moving loop was ~129 ± 74 km s-1. We interpret the shrinking loop and simultaneous outward moving loop as direct evidence for reconnected magnetic field lines during a flare.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 2006
- DOI:
- 10.1051/0004-6361:20054604
- Bibcode:
- 2006A&A...453..335K
- Keywords:
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- Sun: corona;
- Sun: flares;
- Sun: magnetic fields;
- Sun: X-rays;
- gamma rays;
- magnetohydrodynamics (MHD)