Abstract Details
| Name: Suraj Sahu Affiliation: PRL, Ahmedabad Conference ID: ASI2019_474 Title : Thermal & non-thermal processes caused by large-scale restructuring of coronal magnetic fields driven by the flux rope eruption Authors and Co-Authors : Suraj Sahu, Bhuwan Joshi, and Prabir K. Mitra; Udaipur Solar Observatory, Physical Research Laboratory, Udaipur 313001, India Abstract Type : Poster Abstract Category : Sun and the Solar System Abstract : We present a multi-wavelength analysis of a partially erupting filament associated with an M6.7 flare from the active region NOAA 12371 on 2015 June 22. The prominence eruption evolved into a huge, ultrafast, halo coronal mass ejection. In this study, we combine observations from the Atmospheric Imaging Assembly and Helioseismic Magnetic Imager on board the Solar Dynamics Observatory, RHESSI and Big Bear Solar Observatory. GOES 1-8 \AA\ soft X-ray (SXR) flux indicates this flare to be a typical long duration event (LDE), causing prolonged thermal emission for >3 hours. The flare light curves in SXR and extreme ultraviolet (EUV) energy bands suggest distinct peaks during pre-flare and precursor phases which is associated with triggering reconnection and heating of a pre-existing quasi-stationary flux rope. Interestingly, the main phase of the flare was associated with two distinct peaks separated by \sim15 minutes. The \beta\gamma type active region consisted of two spatially well separated sunspot groups with the leading and trailing groups showing unipolar and bipolar magnetic structures on the photosphere, respectively. Chromospheric H\alpha and EUV observations suggest the bipolar sunspot to be associated with a filament lying over the polarity inversion line which partially erupted giving rise to the impulsive emission with strong non-thermal characteristics, causing the first SXR peak. The filament eruption was followed by intense diffused emission from the newly formed post-flare arcade giving rise to the gradual, second SXR peak. In the gradual phase of the flare, we find emission from a second layer of post-flare arcade which was situated high in the corona connecting the positive portion of the bipolar sunspot with the unipolar negative polarity sunspot. We have carried out magnetic field modeling of the active region corona to explain our observations in the light of breakout versus thether cutting models of solar eruptions. |