[en] The problem of plasma expansion in vacuum is quantatively solved. Considered is the process of the flow transition to the automodel regime and a detailed comparison of the obtained solution with the automodel one is carried out. It is seen from the given results that the automodel solution gives a right asymptotic description of the flow, caused by density discontinuity. The automodel solution is not acceptable at the initial stage of discontinuity decomposition and in the vicinity of the ion front. The automodel solution does not also describe oscillations of the electric field in the frequencies of the order of electron plasma, which appear in taking into account the final electron mass. Studied is ion acceleration, as well as the effect of electron temperature on it and on the whole process

[en] The nonlinear stability of shock waves in viscous and heat-conductive fluids is analysed by means of perturbation techniques. The analysis is based on Burgers equation and is limited to one-dimensional disturbances. The shock waves are shown to be unstable with respect to a certain kind of perturbations. (orig.)

No abstract available

[en] New self-similar solutions describing a compression of dense internal regions of single component laser targets are obtained. The solutions constructed represent a process of unlimited energy concentration when approaching the moment of collapse and they are fit for description of non-isentropic compression regimes at which the initial perturbation is a convergent wave. It is pointed out that for shell targets the optimum time dependence of laser power at compression degrees of the 10³-10⁴ order differs from the known asymptotic dependence. The described self-similar solutions give a correct quantitative description of compression and heating of dense regions of laser targets and can be used for optimization of laser compression regimes and estimation of conditions of thermonuclear radiation ignition at laser initiation

No abstract available

[en] Method of computerized tomography with variable radiation energy is descibed. It permits to compensate the distortions in computer-tomographic sections in case of change in tube operating conditions and in visualization of information about tissue composition within the sectional limits. The developed method increase the efficacy of computerized tomography

No abstract available

[en] The ''Photon'' device is aimed at detection of comparatively coarse dust particles with the masses > or approx. 10^-9 g. The device represents a chamber with a thin metal-backed screen oriented in such a way that the screen in transit near nucleus is exposed to solar lighting and the effect of cometary dust particle flux. Detection of dust particles and determination of their parameters are based on optical measurement of the whole square made by dust particles in a screen. Time variation of dust particle flux detected by the screen is shown, mass distribution of the particles is presented

[en] Short communication

No abstract available