Abstract Details
| Name: P. Vemareddy Affiliation: Indian Institute of Astrophysics Conference ID: ASI2017_1262 Title : Recurrent eruptions by converging and shearing polarities in a solar active region Authors and Co-Authors : -- Abstract Type : Oral Abstract Category : Sun and the Solar System Abstract : Solar eruptions include flares and CMEs which influence the heliosphere and planetary atmosphere in a wide range of physical phenomena. Powerful, spectacular eruptions occur in active regions (ARs) with distinct evolving conditions. In the space weather perspective, they are of great scientific interest compared to non-eruptive ARs. To this end, we consider an AR producing faster CMEs recurrently in a week time of observation. Coronal observations from AIA/SDO reveal inverse S-sigmoid morphology to the magnetic structure. The HMI/SDO magnetic field observations show converging and shearing motion of opposite polarity regions co-spatial with the twisted core flux system of the sigmoid. From these observations, we propose continuous shearing and submerging motion of opposite polarity regions lead to formation of sheared arcade, which upon slow reconnection forms flux rope being erupted by tether-cutting reconnection. Various magnetic non-potential parameters support this scenario of energy build up and release by eruptions. We further analyzed modeling aspect of AR magnetic structure and feasibility conditions for eruption. |