Abstract Details
| Name: P. Vemareddy Affiliation: Indian Institute of Astrophysics Conference ID: ASI2015_872 Title : Investigation of Initiation Mechanism of a Flux Rope Eruption Process: SDO Observations Authors and Co-Authors : J. Zhang Abstract Type : Poster Abstract Category : Sun and the Solar System Abstract : An eruption event launched from solar active region (AR) NOAA 11719 is investigated based on coronal EUV observations and photospheric magnetic field measurements obtained from Solar Dynamic Observatory. The AR consists of a filament channel originating from major sunspot and its south section is associated with inverse-S sigmoidal system as observed in AIA passbands. We regard the sigmoid as the main body of the flux rope (FR). There also exists a twisted flux bundle crossing over this FR. The overlying flux bundle exhibits a kink-writhe-rise evolution that has correspondence with rise motion of the FR. The emission measure and temperature along the FR exhibits increasing trend with its rising motion, indicating reconnection in the thinning current sheet underneath the FR. Net magnetic flux of the AR evaluated at north and south polarities showed decreasing behaviour whereas the net current in these fluxes exhibits increasing trend. As the positive (negative) flux is having negative (positive) current, the chirality of AR flux system is negatively (left handed) twisted which is consistent with the chirality of inverse S-sigmoidal FR. This analysis of magnetic fields of source AR suggest that the cancelling fluxes are prime factors to the monotonous twisting of the FR system reaching to a critical state to trigger kink instability and the rise motion. This rise motion is likely led to onset of torus instability resulting to Earth-directed CME and the progressive reconnection in thinning current sheet underneath the rising FR leads to M6.5 flare. |