Simulation of vapor formation for the LEVIS lithium ion source

Summary form only given. The laser evaporation ion source (LEVIS) is an active ion source developed for light ion inertial confinement fusion. A 1.06 /spl mu/m neodynium YAG laser creates a neutral vapor from a thin (0.2-0.5 /spl mu/m) lithium-rich surface. An incident energy density of 0.1-0.2 J/cm/sup 2/ is needed to form a thin vapor layer near the anode with a short-pulse (8 ns FWHM) laser. Lithium vapor formation at these energy densities is being modeled. Different models for the reflectivity and opacity of lithium-bearing metals affect the temperature and density profiles in the anode-cathode gap and the expansion velocity of the neutral vapor obtained with the radiation/hydrodynamics code, TITAN. The calculated time-dependent density and temperature profiles from the Nd:YAG laser vaporization will be used to interpret the spectroscopic and refractive-index-gradient data and as input to a code that calculates the resonant ionization produced by the dye laser.