| Name: | Sripan Mondal |
| Affiliation: | Prime Minister Research Fellow, Indian Institute of Technology (Banaras Hindu University), Varanasi |
| Conference ID : | ASI2024_187 |
| Title : | MHD Simulation of the Magnetic Reconnection and Evolution of Plasmoids in Solar Current Sheets |
| Authors : | Sripan Mondal1, Abhishek K Srivastava1, David I. Pontin2, Ding Yuan3,4, E. R. Priest5
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| Authors Affiliation: | 1 Department of Physics, Indian Institute of Technology (BHU), Varanasi-221005, India
Email:- asrivastava.app@iitbhu.ac.in
2 School of Information and Physical Sciences, University of Newcastle, Australia.
3 Shenzhen Key Laboratory of Numerical Prediction for Space Storm, Institute of Space Science and Applied Technology, Harbin Institute of Technology, Shenzhen, Guangdong, China. Email:- yuanding@hit.edu.cn
4 Key Laboratory of Solar Activity and Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing, China.
5 Mathematics Institute, St Andrews University, KY16 8QR, St Andrews, UK. |
| Mode of Presentation: | Oral |
| Abstract Category : | Sun, Solar System, Exoplanets, and Astrobiology |
| Abstract : | Using MPI-AMRVAC, we perform a 2.5-D numerical MHD simulation of the dynamics and associated thermodynamical evolution of an initially force-free Harris current sheet subjected to an external velocity perturbation under the condition of uniform resistivity. The amplitude of the magnetic field is taken to be 10 Gauss typical of the solar corona. We impose a Gaussian velocity pulse across this current sheet mimicking the interaction of fast magnetoacoustic waves with a current sheet in the solar corona. This leads to a variety of dynamics and plasma processes in the current sheet, which is initially in a quasi-static condition. The initial pulse interacts with the current sheet and splits into a pair of counter-propagating wavefronts, which forms a rarefied region and leads to inflow and a thinning of the current sheet. The thinning results in Petschek type magnetic reconnection followed by tearing instability and plasmoid formation. The reconnection outflows containing outward-moving plasmoids have accelerated motions with velocities ranging from 105-303 km s−1 comparable to many observational studies. The average temperature and density of the plasmoid are found to be 8 MK and 2 times of the background density of the solar corona respectively which are similar to the estimated values from various observations. So the estimates of velocity, temperature and density of plasmoids in our simulation are similar to previously reported values from various solar coronal observations. Therefore, we infer that the external triggering of a quasi-static current sheet by a transient single velocity pulse is capable of initiating magnetic reconnection and plasmoid formation in the absence of a localized enhancement of resistivity in the solar corona.
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