Name: Bhuwan Joshi
Affiliation: Physical Research Laboratory
Conference ID : ASI2022_681
Title : On the formation and eruption of a magnetic flux rope and the flare-CME association: SDO and Udaipur-CALLISTO observations
Authors : Bhuwan Joshi (1), Binal D. Patel (1), Kushagra Upadhyay (1), and Divya Oberoi (2) (1) Udaipur Solar Observatory, Physical Research Laboratory, Udaipur 313001, India (2) National Centre for Radio Astrophysics, Tata Institute of Fundamental Research, Pune 411007, India
Abstract Type: Poster
Abstract Category : Sun and the Solar System
Abstract : Understanding the mechanism for the formation of magnetic flux rope (MFR) in solar active regions (AR) and identification of instabilities that lead to their subsequent eruption are among the most crucial topics of research in contemporary solar physics. Answering these major questions require a thorough analysis of the evolution of magnetic fields of ARs and extensive magnetic field modeling of the solar source region of the coronal mass ejections (CMEs). A comprehensive multi-wavelength case study of the CME-associated flare on 2021 October 9 provides us with an opportunity to investigate some of the key issues related to the origin and eruption of the MFR. The event occurred in the active region NOAA 12882 and, during the occurrence of the flare under study, it was located favorably close to the disk center at N18E08 for a reliable coronal magnetic field modeling. The GOES soft X-ray light curves and AIA extreme ultraviolet imaging observations reveal that this M-class flare displays typical characteristics of the eruptive flares in terms of the formation of parallel flare ribbons and post-flare loop system. The HMI line-of-sight magnetograms exhibit a peculiar distribution of photospheric magnetic flux where the positive and negative fields’ concentrations do not show significant mixing and a sharp polarity inversion line cannot be delineated. Our analysis reveals that the development of MFR is facilitated by the rapid flux emergence and sunspot rotation, started approximately 1-1.5 day before the eruption. The successful eruption of the MFR produced unusual signatures in metric radio dynamic spectrum which shows two type II bursts, implying presence of multiple shocks. While both the fundamental and harmonic are observed for the first, only the harmonic is observed for the second. We explore the existing ideas in both ideal- and resistive-MHD eruption models to understand the CME initiation process in the source region.