Authors: Chris Jia (Stanford University, The University of Michigan), Susan T. Lepri (The University of Michigan), Liang Zhao (The University of Michigan), Jim M. Raines (The University of Michigan), Daniel Welling (The University of Michigan), Jennifer A. Carter (University of Leicester), Simona Nitti (University of Leicester)

The influence of solar wind properties, such as the southward interplanetary magnetic field, on geomagnetic activity has been well established. However, the role of heavy ions (i.e., particles heavier than protons) in the solar wind on geomagnetic storms is not fully understood. Notably, scientific models and simulations of the Earth’s magnetosphere predominately assume a pure-proton solar wind, despite heavy ions constituting over 15% of the solar wind mass density on average during solar maximum periods. By utilizing data from Solar Wind Ion Composition Spectrometer onboard the Advanced Composition Explorer (ACE), we investigate the impact of heavy ion dynamic pressure during Interplanetary Coronal Mass Ejection (ICME) events on Earth’s magnetosphere.