Partially-ionised two-fluid shocks with collisional and radiative ionisation and recombination - multi-level hydrogen model

ABSTRACT Explosive phenomena are known to trigger a wealth of shocks in warm plasma environments, including the solar chromosphere and molecular clouds where medium consists both ionized neutral species. Partial ionization is critical determining behaviour shocks, since ions neutrals locally decouple, allowing for substructure exist within shock. Accurately modelling partially requires careful treatment species, their interactions. Here we study switch-off slow-mode shock using multilevel hydrogen model with collisional radiative recombination rates that implemented into two-fluid (PIP) code, physical parameters typical chromosphere. The differs significantly from magnetohydrodynamic (MHD) solutions due macroscopic thermal energy loss during ionization. In particular, temperature post-shock finite-width cooler MHD temperature. Furthermore, mid lower chromosphere, feature far greater compression than single-fluid analogues. decreased increased reveal importance non-equilibrium evolution media. Since not accurately described by Rankine-Hugoniot jump conditions, it may be incorrect use these infer properties atmospheric shocks.