Plasma spectroscopy of pulsed power driven Z-pinch titanium plasmas

Abstract

We investigate the radiative behavior of a titanium wire load driven on the Z facility. A radiation hydrodynamic model self-consistently driven by a circuit describes the evolution of the plasma and its self-generated environment. Numerical simulations are carried out to compare the total and K-shell soft X-ray emission as a function of the ionization dynamic model. The ionization dynamic models are represented by 1) a time-dependent nonequilibrium (GSO) model, 2) a collisional radiative equilibrium (CRE) model and 3) a local thermodynamic equilibrium (LTE) model. For, all three scenarios the radiation is treated 1) in the free streaming optically thin approximation where the plasma is treated as a volume emitter and 2) in the optically thick regime where the opacity for the lines and continuum is self-consistently calculated online and transported through the plasma. Each simulation is carried out independently to determine the sensitivity of the implosion dynamics to the ionization and radiation model, i.e., how the ionization dynamic model affects the radiative yield and emission spectra. Results are presented for the total and K-shell radiation yields and emission spectra as a function of photon energy from 10 eV to 10 keV.