Hohlraum Simulations with Tabulated Non-LTE Data

Non-LTE atomic kinetics is necessary in ICF hohlraum simulations for adequately modeling high-Z walls and dopants. Detailed treatments of these materials are possible, but at a computational cost far beyond that amenable to use in radiation-hydrodynamic codes, which are restricted to using highly averaged atomic models. An alternative to inline non-LTE calculations is the use of tabulated non-LTE data, assuming a thermal electron distribution and steady-state kinetics. Non-LTE tables have been successfully used in situations with negligible radiation, but generalizing the tables to incorporate the entire range of anticipated radiation spectra seems prohibitive. The Linear Response Matrix (LRM) provides an economical method for tabulating and using non-LTE material data including the effects of radiation. We discuss the formulation of this approach and demonstrate its use in radiation-hydrodynamics hohlraum simulations. The good results obtained from these simulations provide confidence that this method may be used to simultaneously speed up hohlraum simulations and incorporate data from detailed non-LTE models.