Characterization of plasmas produced by a laser line focus

Plasmas produced from cylindrical and planar targets by line-focused 30-ps-duration, high-intensity (∼${10}^{14}$ W/${\mathrm{cm}}^2$), 1064-nm laser pulses have been characterized with a number of diagnostics. Detailed measurements of the morphology and expansion of the electron-density profile were made with picosecond interferometry and compared with predictions of a two-dimensional Eulerian hydrodynamic code. Microscopic filamentation structure in the center regions of the corona, and the generation of a density plateau at $n_c$/4, were features consistently observed which lack quantitative explanations. The implications of these observations for the production of optimum plasma conditions suitable for recombination or collisionally excited x-ray laser schemes are discussed.