Abstract Details

Name: Sindhuja G
Affiliation: Indian Institute of Astrophysics
Conference ID: ASI2021_286
Title : A Study of the Observational Properties of Coronal Mass Ejection Flux Ropes near the Sun
Authors and Co-Authors : G. Sindhuja (Indian Institute of Astrophysics), Nat Gopalswamy (NASA Goddard Space Flight Center)
Abstract Type : Oral
Abstract Category : Sun and the Solar System
Abstract : We present the observational properties of coronal mass ejection (CME) flux ropes (FRs) near the Sun based on a set of 35 events from solar cycle 24 (2010-2017). We derived the CME FR properties using the Flux Rope from Eruption Data technique. According to this technique, the geometrical properties are obtained from a flux-rope fit to CMEs and the magnetic properties from the reconnected flux in the source region. In addition, we use the magnetic flux in the dimming region at the eruption site. Geometric properties like radius of the FR and the aspect ratio are derived from the FR fitting. We found that the mean values of the poloidal flux, toroidal flux, axial magnetic field strength (at 10 solar radii) and the radius of the flux rope are 4.3x10^21 Mx, 7.3x10^20 Mx, 18.8 mG and 4.6 Rs, respectively. The reconnected flux exhibits a positive correlation with flare fluence in soft X-rays (SXRs), peak flare intensity in SXRs, CME speed, and kinetic energy, with correlation coefficients (cc) 0.78, 0.6, 0.48, and 0.55, respectively. We found a moderate positive correlation between magnetic flux in the core dimming regions and the toroidal flux obtained from the Lundquist solution for a force-free FR (cc=0.43). Furthermore, we correlate the core dimming flux and CME mass (cc=0.34). The area of the core dimming region shows a moderate correlation with the radius of the FR (cc=0.4). Thus, we infer that greater magnetic content (poloidal and toroidal fluxes) indicates a more energetic eruption in terms of flare size, CME speed, kinetic energy, mass, and radius of the FR, suggesting important implications for space weather predictions. In addition, to this results, I will discuss the application of Visible Emission Line Coronagraph (VELC) onboard ADITYA-L1 data for this kind of studies.