On-Disc Observations of Flux Rope Formation Prior to Its Eruption |
| |
| Authors: | A W James " target="_blank">L M Green " target="_blank">E Palmerio " target="_blank">G Valori " target="_blank">H A S Reid " target="_blank">D Baker " target="_blank">D H Brooks " target="_blank">L van Driel-Gesztelyi " target="_blank">E K J Kilpua |
| |
| Institution: | 1.Mullard Space Science Laboratory,University College London,Dorking,UK;2.Department of Physics,University of Helsinki,Helsinki,Finland;3.SUPA School of Physics and Astronomy,University of Glasgow,Glasgow,UK;4.College of Science,George Mason University,Fairfax,USA;5.Observatoire de Paris, LESIA,FRE 2461 (CNRS),Meudon Principal Cedex,France;6.Konkoly Observatory of the Hungarian Academy of Sciences,Budapest,Hungary |
| |
| 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. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
