Non-LTE modeling and simulations for spectroscopic analysis of stainless steel Z-pinch Plasma

We have developed a collisional-radiative spectroscopic model that combines the completeness of highly averaged Rydberg states models with the accuracy of detailed models for all important excited states. Our model includes an abundance of levels and atomic structure data as well as collisional and radiative processes including excitation, ionization, and recombination level couplings. This approach was used to generate a Stainless-Steel (SS) atomic model to analyze the implosion dynamics of an array of SS wires on the Z and/or refurbished Z accelerator at Sandia National Laboratories. We investigate the ionization dynamics and generate K- and L-shell spectra using the conditions characteristic of the peak emission in the Z accelerator, as calculated by a 1D non-LTE radiation hydrodynamics model. The non-LTE populations are obtained by generating the detailed atomic data for Fe, Ni, and Cr ions, the primary constituents of SS. The simulations self-consistently include the effects of radiation transport and line broadening. Our atomic data includes level-specific dielectronic recombination (DR) data for recombination from H to He-like ions in order to investigate the Ly_alpha satellite lines that are useful for diagnosing Doppler broadening in a Z-pinch plasma at stagnation.