Spectroscopy diagnostics of a low temperature laser ablated LiAg plasma plume

In experiments performed at Sandia National Laboratories, laser-generated L iAg plasma plumes were produced by irradiation of solid targets using a 10 ns pulse duration, 1 x 10(8) W/cm(2) intensity Nd YAG laser. Time- and spat ially resolved (along a direction normal to the target's surface) optical s pectra were recorded with a framing spectrograph. The observed spectra cons ist of optical line emission in Li and Ag atoms. Evidence of ions in the pl ume is suggested by the presence of a forbidden line and Stark-broadened li ne shapes. A spectroscopic model based on time-dependent collisional-radiat ive atomic kinetics that self-consistently calculate the Li and Ag level po pulations in conjunction with detailed line shapes and radiation transport is used to interpret the data. From this analysis, temperature, density, an d ionization in the plume as a function of time and position along the norm al to the target surface are extracted. (C) 2001 American Institute of Phys ics.