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SDO/AIA Observations of a Partially Erupting Prominence

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 نشر من قبل Durgesh Tripathi Dr
 تاريخ النشر 2013
  مجال البحث فيزياء
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We report an observation of a partially erupting prominence and associated dynamical plasma processes based on observations recorded by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory (SDO). The prominence first goes through a slow rise (SR) phase followed by a fast rise (FR). The slow rise phase started after a couple of small brightenings seen toward the footpoints. At the turning point from SR to FR, the prominence had already become kinked. The prominence shows strong brightening at the central kink location during the start of FR. We interpret this as internal magnetic reconnection occurring at a vertical current sheet forming between the two legs of the erupting prominence (flux-rope). The brightening at the central kink location is seen in all the EUV channels of AIA. The contributions of differential emission at higher temperatures are larger compared to that for typical coronal temperatures supporting a reconnection scenario at the central kink location. The plasma above the brightening location gets ejected as a hot plasmoid-like structure embedded in a CME, and those below drain down in the form of blobs moving towards the Suns surface. The unique time resolution of the AIA has allowed all of these eruptive aspects, including SR-to-FR, kinking, central current sheet formation, plasmoid-like eruption, and filament splitting, to be observed in a single event, providing strong and comprehensive evidence in favour of the model of partially erupting flux ropes.



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