Density and temperature profile formation in long risetime Saturn, aluminum, single array implosions

Summary form only given, as follows. The problem of tailoring the current risetime (and eventually the pulseshape) with the goal of increasing kilovolt X-ray emissions has recently begun to be addressed in two recent series of Al:Mg wire array Z-pinch implosions. These experiments were conducted on the Saturn pulse-power generator operated in a long pulse-risetime (approximately 150 ns) mode. Sufficient time-resolved and time-integrated X-ray data were obtained to allow plasma density and temperature profiles to be inferred by fitting measured X-ray data to that calculated by a collisional-radiative equilibrium (CRE) model. In fitting the time-integrated data, the plasma was assumed to be uniform (i.e., 0-D-like), while in fitting the time resolved data, the plasma was taken to have one-dimensional (1-D) radial gradient structure. While both analyses showed the same trends in plasma conditions as a function of load mass and wire number, the uniform plasma assumption yielded higher electron temperatures, lower core plasma densities, and higher radiating plasma-mass fractions than those obtained from the more detailed, time-resolved analysis. One-dimensional, shell-like, MHD implosion calculations, under variety of zoning, initial condition, and transport coefficient assumptions, have been carried out to model these experiments. Comparisons of the calculated temperature and density profiles to those inferred from the data analysis are made to determine how closely 1-D computer calculations can be made (and under what assumptions) to replicate the time-resolved profile structures inferred from the data analysis.