UC San Diego

Optical emission spectroscopic studies have been carried out on a tin plasma generated using 1064-nm, 8-ns pulses from a Nd: yttrium aluminum garnet laser. Temperature and density were estimated from the analysis of spectral data. The temperature measurements have been performed by Boltzmann diagram method using singly ionized Sn lines, while density measurements were made using the Stark broadening method. An initial temperature of 3.2 eV and density of 7.7 1017 cm−3 were measured. Temporal and spatial behaviors of electron temperature and density in the laser-generated tin plasma have been analyzed. Time evolutions of density and temperature are found to decay adiabatically at early times. The spatial variation of density shows approximately 1/ z dependence. The time-integrated temperature exhibits an appreciable rise at distances greater than 7 mm. This may be caused by the deviation from local thermodynamic equilibrium at larger distances from the target surface.