Non-­Equilibrium Ionization Modeling of Coronal Mass Ejections

Coronal Mass Ejections, or CMEs, are solar events that eject plasma and magnetic flux into interplanetary space. Contemporary sources have noted that the onset of CMEs are caused by some instability of the coronal magnetic field, and further allows heating of plasma upon expansion. Additionally, plasma that leaves the lower solar corona does not remain in ionization equilibrium due to the rapid expansion of plasma. We investigate the evolution of charge states of CME plasma using non-equilibrium ionization (NEI) modeling. These NEI models include radiative cooling and serve as baseline studies for special cases where no heat is being added to the plasma. Each of the simulated CMEs have initial conditions characteristic of active regions. Various function inputs, such as initial temperature, density and final velocity, allow us to examine the influence of certain parameters on the charge state evolution. The results of our project show that plasma originating from active regions display charge state evolutions substantially dependent on initial density and temperature. The CMEs starting with higher plasma density often show an abundance of lower charge states above the freeze-in height. Simulations starting from higher temperatures often show abundance peaks at charge states with closed electron shells.