Trigger of Successive Filament Eruptions Observed by SDO and STEREO
Informazioni aggiuntive
Autori
Dhara S. K. .,
Belur R.,
Kumar P.,
Banyal R. K. .,
Mathew S. K. .,
Joshi B.
Tipo
Articolo pubblicato in rivista scientifica
Anno
2017
Lingua
Inglese
Abstract
Using multiwavelength observations from the Solar Dynamics Observatory(SDO) and the Solar Terrestrial Relations Observatory (STEREO), we investigate the mechanism of two successive eruptions (F1 and F2) of a filament in active region NOAA 11444 on 27 March 2012. The filament was inverse J-shaped and lay along a quasi-circular polarity inversion line (PIL). The first part of the filament erupted at tilde2$$:$$30 UT on 27 March 2012 (F1), the second part at around 4:20 UT on the same day (F2). A precursor or preflare brightening was observed below the filament main axis about 30 min before F1. The brightening was followed by a jet-like ejection below the filament, which triggered its eruption. Before the eruption of F2, the filament seemed to be trapped within the overlying arcade loops for almost 1.5 h before it successfully erupted. Interestingly, we observe simultaneously contraction (tilde12 km s^$$-1$$) and expansion (tilde20 km s^$$-1$$) of arcade loops in the active region before F2. Magnetograms obtained with the Helioseismic and Magnetic Imager (HMI) show converging motion of the opposite polarities, which result in flux cancellation near the PIL. We suggest that flux cancellation at the PIL resulted in a jet-like ejection below the filament main axis, which triggered F1, similar to the tether-cutting process. F2 was triggered by removal of the overlying arcade loops via reconnection. Both filament eruptions produced high-speed (tilde1000 km s^$$-1$$) coronal mass ejections.
Rivista
Solar Physics
Volume
292
Pagina inizio
145
Parole chiave
irsol-refereed-scientific-papers
