Abstract Details
| Name: Pawan Kumar Affiliation: Patna University, Patna Conference ID: ASI2025_683 Title : Parametric Study to Understand the Onset of Confined and Eruptive Flares Authors and Co-Authors : Pawan Kumar 1, Sadashiv 1, Sanjay Kumar 1, Sushree S Nayak 2 Abstract Type : Poster Abstract Category : Sun, Solar System, Exoplanets, and Astrobiology Abstract : In this work, we have studied the influence of different parameters on the onset of confined and eruptive flares > M-class hosted by complex active regions using observations and magnetic field modeling. We have utilized the non-force-free-field (NFFF) extrapolation model to perform the extrapolation and estimated the parameters at different heights. Our investigations include evolution: 1) much prior to the peak flaring phase, 2) during the flare, and 3) after the decay phase. We have examined the changes in magnetic flux, Doppler velocity, vertical, horizontal, and total current densities, squashing factor, twist, magnetic energy, shear angle, and Lorentz force computed from the extrapolation. From the extrapolations, important is the absence of flux rope in the confined flares compared to the eruptive cases. Interesting topology such as magnetic null points, quasi-separatrix layers (QSLs), and/or hyperbolic flux tubes (HFTs) are identified near the confined flares. This points towards a crucial role of null point reconnections and/or sleeping reconnections at the QSLs in triggering the confined events. Whereas highly sheared arcades or flux ropes are found to be important in the eruptive events. From the evolution of different quantities for both confined and eruptive cases, we observe that average |B|, |J| and |JxB| are decreased slightly just before the onset of the flares whilst the mean shear angle is decreased by a large value near the flaring time but increased after that. The mean flux remains almost the same throughout the duration. This is suggestive of devoid of any signature of significant flux cancellation/emergence, which may lead to the flares. Remarkably, after the flares, average |B|, |J| and |JxB| are found to decrease for the confined flares but increase for the eruptive flares. This indicates that the relaxation process of the confined flares is different from the eruptive flares. |