Observations of simultaneous coronal loop shrinkage and expansion during the decay phase of a solar flare

Khan, J.I., Fletcher, L. and Nitta, N.V. (2006) Observations of simultaneous coronal loop shrinkage and expansion during the decay phase of a solar flare. Astronomy and Astrophysics, 453(1), pp. 335-339. (doi: 10.1051/0004-6361:20054604)

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 <i>Yohkoh</i> 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.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Khan, Dr Josef and Fletcher, Professor Lyndsay
• Authors: Khan, J.I., Fletcher, L., and Nitta, N.V.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Astronomy and Astrophysics
• Publisher: EDP Sciences
• ISSN: 0004-6361
• ISSN (Online): 1432-0746
• Copyright Holders: Copyright © 2006 EDP Sciences
• First Published: First published in Astronomy and Astrophysics 453(1):335-339
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher