Numerical simulation of plasma implosion under radiative heating of the inlet hole walls of hohlraum target

International audienc

A converging shock wave for ignition of a pre-compressed target of laser thermonuclear fusion

Abstract: The formation of a convergent shock wave in a homogeneous spherical target is studied, the outer layer of which is heated by a stream of monoenergetic fast electrons with a given particle energy. The ablation pressure generating the wave is formed by the spherical expansion of a layer of a heated substance, the optical thickness of which remains constant throughout the heating process and is equal to the product of the initial depth of heating by the thickness of the layer. The investigations were performed on the basis of numerical calculations on a one-dimensional hydrodynamic program with reference to one of the most perspective methods of ignition of a target of laser thermonuclear fusion - the ignition of a pre-compressed target by a shock wave.Note: Research direction:Mathematical modelling in actual problems of science and technic

Al plasma jet formation via ion stream compression by surrounding low-Z plasma envelope

In our earlier papers it was demonstrated that the plasma pressure decreases with the growing atomic number of the target material. In this context a question arose about the possibility to collimate the Al plasma outflow by using the plastic plasma as a compressor. For that purpose a plastic target with an Al cylindrical insert of 400 μm in diameter was used. The experiment was carried out at the PALS laser facility. The laser provided a 250 ps (FWHM) pulse with the energy of 130 J at the third harmonic frequency (λ3 = 0.438 μm). The focal spot diameters (ΦL) 800, 1000, and 1200 μm ensured predominance of the plastic plasma, its transversal extension being large enough for the effective Al plasma compression. To study the Al plasma stream propagation and its interaction with the plastic plasma, a 3-frame interferometric system and 4-frame x-ray camera were used. The information on distribution of electron temperature in the outflowing Al plasma was provided by x-ray spectroscopy. The experimental results reported in the paper are discussed by virtue of a simple theoretical analysis

Al plasma jet formation via ion stream compression by surrounding low-Z plasma envelope

In our earlier papers it was demonstrated that the plasma pressure decreases with the growing atomic number of the target material. In this context a question arose about the possibility to collimate the Al plasma outflow by using the plastic plasma as a compressor. For that purpose a plastic target with an Al cylindrical insert of 400 μm in diameter was used. The experiment was carried out at the PALS laser facility. The laser provided a 250 ps (FWHM) pulse with the energy of 130 J at the third harmonic frequency (λ3 = 0.438 μm). The focal spot diameters (ΦL) 800, 1000, and 1200 μm ensured predominance of the plastic plasma, its transversal extension being large enough for the effective Al plasma compression. To study the Al plasma stream propagation and its interaction with the plastic plasma, a 3-frame interferometric system and 4-frame x-ray camera were used. The information on distribution of electron temperature in the outflowing Al plasma was provided by x-ray spectroscopy. The experimental results reported in the paper are discussed by virtue of a simple theoretical analysis