Mapping Magnetic Field Lines for an Accelerating Solar Wind and Its Application in the Space Weather

Kurzfassung

The mapping of magnetic field lines is crucial for studies of the solar wind, sources of the solar wind, and propagation of solar energetic particles from the Sun to the Earth and beyond. We employ Tasnim et al., 2018’s magnetohydrodynamic (MHD) solar wind (SW) model that includes the effects of solar wind acceleration, non-radial intrinsic magnetic fields and flows at the source surface/inner boundary, and conservation of angular momentum to predict the magnetic field as a function of position between the Sun and the Earth. We fit the model to near-Earth observations of the Wind spacecraft during the solar rotation period of 19 May – 16 June 2020 and estimate the solar wind plasma and magnetic field components from the inner boundary to 1 AU. To validate the above SW model, we compare predictions of density and ion temperature close to the Sun with Parker Solar Probe data for the period. In addition, we extend the mapping approach of Tasnim et al., 2019 into a robust and automated technique where field lines are mapped by stepping along the magnetic field B. This automated mapping capability allows us to map the magnetic field lines from the Sun to Earth for observational data from multiple spacecraft STEREO A, Wind, and ACE. The combined magnetic field and plasma data from STEREO-A and Wind allow the prediction of magnetic maps at longitudes from the Sun’s east limb to the disk center and from the disk center to the Sun’s west limb, respectively. The above SW model and the mapping approach provide us the scope to better understand space weather involving electromagnetic fields, plasma, and energetic particles from the Sun.