Vacuum ultra-violet emission spectra from laser-produced plasmas

The electromagnetic emission from plasmas produced by irradiating solid targets with focused light from Q -spoiled ruby lasers is recorded with grazing- and normal-incidence spectrographs as a function of plasma radius and of distance from the target The plasma density and temperature are thereby evaluated. Observed linewidths of the order of 10 3 cm -1, in the grazing-incidence region are ascribed to pressure broadening with corresponding electron densities in excess of 10 20 cm -3 . The thermodynamic state of the plasma is considered A brief discussion is given of the effects of varying laser power and target preparation on the degree of ionization of the laser-produced plasma, and hence on the extension of its use as a spectroscopic source for laboratory astrophysics.