In-line Non-equilibrium Ionization Calculation Module with Kappa Distribution in MHD Simulations

Non-equilibrium ionization (NEI) is essentially required in many astrophysical environments where the thermodynamic time scale is shorter than the ionization time scale. Many studies have shown that ionization cannot reach equilibrium in shocks because of rapid heating. Therefore, it is necessary to account for time-dependent ionization when interpreting observations of solar eruptions. Furthermore, the ionization and recombination processes are also significantly affected by energetic particles due to several acceleration processes. In this work, we apply a non-equilibrium ionization calculation module integrated into a well-developed MHD code, Athena, to perform in-line NEI calculations. This new approach is to achieve a more accurate analysis of the non-equilibrium ionization by combining in-line NEI calculation and kappa distribution of particles in MHD simulations. In this mode, the time-dependent ionization equations are solved using the Eigenvalue method, in which the ionization/recombination rates are pre-built into the structured table for different kappa values. We then compare the features of charge states with different kappa crossing shock fronts in coronal environments.