Using In Situ and Remote Sensing Data to Model the Plasma Flow throughout the Heliosphere

Abstract:

The solar wind is a turbulent medium with physical properties fluctuating on multiple scales. We model three-dimensional solar wind plasma flow using our own software, Multi-Scale Fluid-Kinetic Simulation Suite, which, in addition to the thermal solar wind plasma, takes into account charge exchange of solar wind protons with interstellar neutral atoms and treats nonthermal ions (pickup ions, PUIs) born during this process as a separate fluid. Additionally, our model includes a description of turbulence generated by PUIs. For this investigation, we run our model using plasma and turbulence parameters from OMNI data as time-dependent boundary conditions at 1 AU for the Reynolds-averaged MHD equations and investigate the evolution of plasma and turbulent fluctuations along the trajectory of the New Horizons spacecraft, which recently passed by Pluto nearly ten years after launch. We also present solar wind simulations starting at 0.1 AU outwards using interplanetary scintillation data as boundary conditions. Simulations are compared with OMNI and STEREO data. The purpose of this study is to create a time-dependent solar wind model capable of reproducing the plasma flow, magnetic field, and turbulence along the trajectories of Solar Probe Plus and Solar Orbiter.