AWSoM simulations for Parker Solar Probe

Authors: Bart van der Holst (University of Michigan)

We compare Alfvén Wave Solar atmosphere Model (AWSoM) simulations with the tenth orbit of NASA’s Parker Solar Probe (PSP). The perihelion of this encounter is 13.3 Rsun reached at 2021-11-21. In the AWSoM model, the coronal heating and acceleration is addressed via low-frequency, reflection-driven Alfvén waves. The nonlinear interaction of counter-propagating waves results in a turbulent energy cascade. The dissipated wave energy is then apportioned to electron and anisotropic proton temperatures. We check the ability of the simulations to reproduce the observed plasma mass density, velocity, and magnetic fields, temperature anisotropy, and wave turbulence levels. To deduce the sources of the solar wind observed by PSP we use the AWSoM model to determine the field line connectivity between PSP locations and the Sun. We will also describe the large-scale structures that PSP might have passed through, for instance whether PSP was in the fast or slow wind and when PSP crossed the heliospheric current sheet. We emphasize the proton temperature anisotropies and check for the occurrence of plasma instabilities.