Experimental, numerical, and theoretical studies of x radiation and radiative thermal conductivity in a dense laser plasma with multicharged ions

Studies have been carried out of the x radiation and radiative thermal conductivity of a plasma with multicharged ions produced by irradiating planar targets of various configurations with the focused beam from a neodymium laser over an intensity range 10{sup 13}-10{sup 14} W/cm{sup 2}. The experimentally measured x-ray parameters in the spectral range 10-100 {angstrom} and their time dependence as functions of the thickness and diameter of copper targets have been compared with the results of calculations using a specially developed radiative hydrodynamics code. Analysis of the numerical and experimental data confirms that the radiative thermal conductivity makes a substantial contribution to the energy transport process in the dense regions of the plasma corona with n{sub e} > 10{sup 21} cm{sup {minus}3} and that a re-emission zone develops at the surface of targets made of elements with intermediate atomic number (Z > 20). Techniques are proposed for diagnosing the dense regions of the plasma, based on measuring the refraction and absorption of x-ray probe radiation. 31 refs., 11 figs.