[en] The coefficient of limitation f of the electronic thermal conduction in a laser plasma upon spherical exposure of targets has been studied in experiments with the 6-beam ''Progress'' laser facility (λ=1.054 μm) in the range of heating radiation flux densities of q ∼ (0.5-5)x10¹⁵ W/cm². In order to determine f the results of measurements of the energy absorbed by the target, the average rate of target compression and the yield of X-ray lines of multicharged Si ions were compared with the results of numerical calculations performed in the ''Zarya'' program over a wide range of F variations. It is shown that f falls with rise in q

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[en] The results of calculations of LTF targets, which were performed using the ''Zarya'' program with allowance for the spectral transfer of radiation, a particles, fast electrons, and the limitation of electronic thermal conductivity, are discussed. The specifications for the targets and parameters of a laser for producing a flash and for a hybrid reactor, are determined

[en] An investigation was made of x-ray images of gas-filled microspheres (shell targets) approx.120 μ in diameter irradiated at power densities of (1--2) x 10¹⁴ W/cm². Camera-obscura photographs were obtained of targets with aspect ratios R/ΔRroughly-equal30--50 and 200--300, which were recorded in the course of experiments carried out using the Sokol facility

[en] A comparison of the experimental yields of x-ray lines of multiply charged silicon ions with the results of numerical calculations carried out using the Zarya program was used to find the coefficient representing the limit set on the electron thermal conductivity of a laser plasma. The experiments were carried out at laser radiation power densities 1 = (1--2) x 10¹⁴ W/cm² (lambda = 1.06 μ) reaching the surface of an SiO₂ shell target in the case of spherical irradiation geometry. The best agreement between the calculations and the experiments was obtained for a weak limitation on the electron thermal conductivity

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[en] An interpretation is presented of the results of research into the gasdynamic parameters and the compression dynamics of gas-filled microspheres with R/ΔR = 30-300, obtained with the SOKOL facility at incident and absorbed laser energy flux densities q ∼ (0.1-4.0) · 10¹⁴ W/cm² and q_a ∼ (0.1-1.0) · 10¹⁴ W/cm² and at specific energy inputs ε₀ ∼ 0.003-0.3 J/ng. The dependences of the average flight velocity of the shell towards the center, of the average scatter rate of the laser plasma, of the mass flow rate, of the average ablation pressure, of the hydrodynamic efficiency, and of the mass coefficient on the indicated physical parameters are investigated. The results are used to reconcile and optimize the parameters of the laser + target system so as to increase the specific energy input. The heat-conduction confinement coefficient is obtained in greater detail by comparison of the experimental results with those of gasdynamic calculations

[en] The results are generalized on investigations of the gasodynamic parameters of the compression dynamics for glass gas-filled microspheres with R/ΔR=30-300 measured with the ''Sokol'' installation. The flux densities of the incident and absorbed laser energy are q ∼ (0.1-4.0)x10¹⁴ W/cm² and q_n ∼ (0.1-1.0)x10¹⁴ W/cm² and the specific energy contributions ε₀ ∼ 0.03-0.3 j/ng. The dependences of the mean velocity of flight of the shell toward the center, the mean expansion velocity of the laser plasma, the flow rate of mass, mean ablation pressure, hydrodynamic efficiency and mass coefficient on the aforementioned physical parameters are investigated. The matching and optimization of the parameters of the laser-target system toward increasing the specific energy contribution are carried out on the basis of the results obtained. The value of the electron heat conduction restriction coefficient is determined in greater detail by comparing the experimental results with those of gasodynamic calculations. The results of the investigation are compared with those for theoretical models, results of gasodynamic calculations and with the data obtained with the ''Kalmar'', ''Delfin'', ''Vulkan'', ''Chroma-1'', ''Omega'' and ''Argus'' installations

[en] The ''shock wave'' and ''ions'' methods are described for measuring the laser energy absorbed by a target. The aim of these methods is to determine the absorbed energy by calculation from the shock wave (R--t) parameters and ion currents. Methods are also described for determining the velocity distribution function of the plasma ions and the electron temperature in the critical-density corona region using ion collectors. These methods were used in a study of the effects of irradiation of gas-filled glass microspheres in the Sokol high-power laser facility