On-disc observations of flux rope formation prior to its eruption

James, A.W., Green, L.M., Palmerio, E., Valori, G., Reid, H.A.S. , Baker, D., Brooks, D.H., van Driel-Gesztelyi, L. and Kilpua, E.K.J. (2017) On-disc observations of flux rope formation prior to its eruption. Solar Physics, 292(5), 71. (doi: 10.1007/s11207-017-1093-4)

[img]
Preview
Text
141198.pdf - Published Version
Available under License Creative Commons Attribution.

3MB

Abstract

Coronal mass ejections (CMEs) are one of the primary manifestations of solar activity and can drive severe space weather effects. Therefore, it is vital to work towards being able to predict their occurrence. However, many aspects of CME formation and eruption remain unclear, including whether magnetic flux ropes are present before the onset of eruption and the key mechanisms that cause CMEs to occur. In this work, the pre-eruptive coronal configuration of an active region that produced an interplanetary CME with a clear magnetic flux rope structure at 1 AU is studied. A forward-S sigmoid appears in extreme-ultraviolet (EUV) data two hours before the onset of the eruption (SOL2012-06-14), which is interpreted as a signature of a right-handed flux rope that formed prior to the eruption. Flare ribbons and EUV dimmings are used to infer the locations of the flux rope footpoints. These locations, together with observations of the global magnetic flux distribution, indicate that an interaction between newly emerged magnetic flux and pre-existing sunspot field in the days prior to the eruption may have enabled the coronal flux rope to form via tether-cutting-like reconnection. Composition analysis suggests that the flux rope had a coronal plasma composition, supporting our interpretation that the flux rope formed via magnetic reconnection in the corona. Once formed, the flux rope remained stable for two hours before erupting as a CME.

Item Type:Articles
Additional Information:** From Springer Nature via Jisc Publications Router. ** History: ** received: 05-12-2016 ** accepted: 09-04-2017 ** epub: 01-05-2017 ** collection: 01-05-2017 ** Licence for this article: http://creativecommons.org/licenses/by/4.0/
Keywords:Article, Corona: structures, Coronal mass ejections: initiation and propagation, Magnetic fields: photosphere, Radio emission: active regions
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Reid, Dr Hamish
Authors: James, A.W., Green, L.M., Palmerio, E., Valori, G., Reid, H.A.S., Baker, D., Brooks, D.H., van Driel-Gesztelyi, L., and Kilpua, E.K.J.
College/School:College of Science and Engineering > School of Physics and Astronomy
Journal Name:Solar Physics
Publisher:Springer
ISSN:0038-0938
ISSN (Online):1573-093X
Published Online:01 May 2017
Copyright Holders:Copyright © 2017 The Authors
First Published:First published in Solar Physics 292(5): 71
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record

Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
631581Consolidated grant in solar and astrophysical plasmasLyndsay FletcherScience & Technology Facilities Council (STFC)ST/L000741/1S&E P&A - PHYSICS & ASTRONOMY