The Interaction of Solar Eruptions and Large-Scale Coronal Structures Revealed Through Modeling and Observational Analysis

We use numerical and observational approaches to explore how the interaction of a coronal mass ejection (CME) with preexisting structures in the solar atmosphere influences its evolution and space weather effects. We study two aspects of CME evolution: deflection of the CME’s propagation direction, and expansion. First, we perform a statistical study of the influence of coronal holes on CME trajectories for more than 50 events during years 2010-2014. Second, we use the Space Weather Modeling Framework (SWMF) to model CME propagation in the Alfven Wave Solar Model (AWSoM), which includes a sophisticated treatment of the physics of coronal heating and solar wind acceleration. The major progress in these simulations is that the initial conditions of the eruptions are highly data-constrained. From the simulations, we determine the CME’s trajectory and expansion. We calculate the pile-up of material along the front and sides of a CME due to its expansion, and constrain the properties of the pile-up under a range of conditions. Finally, we will discuss the connection between these plasma density structures and the acceleration of protons to energies relevant to space weather.