Spectroscopic diagnostics of carbon and aluminum laser-produced plasmas

VUV emission spectra of plasmas produced by focusing laser radiation with intensity of 10 no. 10-1011 W/cm2 on carbon and aluminum targets were studied. Using the partial local thermodynamic equilibrium model for an electron density exceeding 1017 cm-3, the spectroscopic diagnostics and the analysis of ion composition of plasmas were carried out. The electron temperatures determined for carbon and aluminum plasmas from the ratio of intensities of ionic lines were found to be 8 ± 3 eV and 11 ± 4 eV, respectively. Stark broadening of aluminum lines was measured and parameters of electron broadening were determined. Using the spatially resolved measurement of Stark line broadening, the spatial density distribution and the law of electron gas expansion were found. The electron gas in the hot region of size 5 mm with an average density of (5 ± 2) x 1017 cm-3 experienced one-dimensional expansion according to the law 1/z1.1 with increasing distance z from the target