| Name: | Samriddhi Sankar Maity |
| Affiliation: | Indian Institute of Science and Indian Institute of Astrophysics |
| Conference ID : | ASI2024_683 |
| Title : | Photospheric Lorentz force changes in eruptive and confined solar flares |
| Authors : | Samriddhi Sankar Maity (1,2), Ranadeep Sarkar (3), Piyali Chatterjee (1), Nandita Srivastava (4) |
| Authors Affiliation: | (1) Indian Institute of Astrophysics, Bengaluru, India - 560034
(2) Indian Institute of Science, Bengaluru, India - 560012
(3) University of Helsinki, Helsinki, Finland
(4) Udaipur Solar Observatory, Physical Research Laboratory, Udaipur, India - 313004 |
| Mode of Presentation: | Poster |
| Abstract Category : | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract : | Solar flares often leave distinct imprints on the photospheric magnetic field, resulting due to abrupt and permanent changes in the downward-directed Lorentz force within specific regions of the active area during the flaring episode. The primary objective of this study is to differentiate between eruptive and confined solar flares based on variations in vertical Lorentz force. We have selected 26 eruptive and 11 confined major solar flares, all are stronger than GOES M5 class, observed from 2011 to 2017. We used SHARP vector-magnetograms sourced from NASA's Helioseismic and Magnetic Imager (HMI) to analyse these events. Additionally, we have compared the data with that of two synthetic flares from a $\delta$-sunspot simulation described in Chatterjee et al. [Phys. Rev. Lett. 116, 101101 (2016)]. Our results involves estimating changes in the horizontal magnetic field and the total Lorentz force within an area surrounding the polarity inversion line (PIL), which encompasses the flare's location. Our findings reveal a rapid increase in the horizontal magnetic field along the flaring PIL, accompanied by a significant alteration in the downward-directed Lorentz force in the same vicinity. It is noteworthy that all the confined events under scrutiny exhibit a total change in Lorentz force of less than $1.8 \times 10^{22}$ dyne, a crucial threshold for effectively distinguishing eruptive from confined flares. Furthermore, our analysis suggests that the change in total Lorentz force is influenced by the reconnection height in the solar corona during the onset of the associated flare. These results have substantial implications for understanding the transmission of upward impulse related to coronal mass ejections associated with solar flares. |
