Atomic Modeling of Photoionization Fronts in Nitrogen Gas*

Photoionization fronts play a dominant role in many astrophysical situations, but remain difficult to achieve in a laboratory experiment. Recent papers have suggested that photoionization fronts can be generated in nitrogen gas held at ten atmospheres of pressure and is irradiated by a source with a radiation temperature of T_R ∼ 100 eV. We present a suite of one-dimensional numerical simulations using the Helios multi- material radiation hydrodynamics code. We present the results of varying the atomic kinetics and radiative transfer on the formation of a photoionization front and the results of a suite of models that vary the nitrogen pressure and peak radiation temperature.