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arXiv · 2305.12124

Evaluation of Coronal and Interplanetary Magnetic Field Extrapolation Using PSP Solar Wind Observation

Yuechun Song
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Abstract

Using solar wind observation near PSP perihelions as constraints, we have investigated the parameters in various PFSS model methods. It's found that the interplanetary magnetic field extrapolation with source surface height $R_\mathrm{SS} = 2\,Rs$ is better than that with $R_\mathrm{SS} = 2.5\,Rs$. HMI and GONG magnetograms show similar performance in the simulation of magnetic field variation, but the former appears to have a slight advantage in reconstruction of intensity while the latter is more adaptable to sparser grids. The finite-difference method of constructing eigenvalue problem for potential field can achieve similar accuracy as analytic method and greatly improve the computational efficiency. MHD modeling performs relatively less well in magnetic field prediction, but it is able to provide rich information about solar-terrestrial space.

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Yuechun Song. 2023-05-20. Evaluation of Coronal and Interplanetary Magnetic Field Extrapolation Using PSP Solar Wind Observation. https://doi.org/10.1088/1674-4527/acd52a

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