The paper is aimed at optimization of parameters of a copper plasma jet produced at the DPF-1000U device, in which the inner electrode face was conically shaped. Preliminary information was obtained by numerical simulations of the plasma jet creation for different copper cones with the use of the two-dimensional magneto-hydrodynamic code KAROL. The simulations suggested that the cone height in the range of 4–7 cm should ensure a good plasma jet quality. The experimental data delivered by means of a 16-frame laser interferometer and a four-frame X-ray pinhole camera fully confirmed this conclusion. In the paper, we demonstrate the results for a 5 cm height cone. The eroded Cu plasma, swept up by the deuterium plasma sheath, was accelerated axially and compressed to very small diameter (3 mm) with an electron density of 7 × 1018 cm−3. The Cu plasma jet achieved a velocity of 5 × 107 cm/s and reached in the period of about 230 ns a distance (length) of 7 cm. The above results prove a successful adaptation of the plasma focus device to the metallic plasma jet generator.

This paper aims at investigation of efficiency of an ablative plasma energy transfer into a massive aluminum target using different atomic number ablators. For this reason, several target materials representing a wide range of atomic numbers (Z = 3.5–73) were used. The experiment was carried out at the iodine Prague Asterix Laser System. The laser provided a 250 ps pulse with energy of 130 J at the third harmonic frequency (λ3 = 0.438 μm). To study the plasma stream configurations a four-frame X-ray pinhole camera was used. The electron temperature of the plasma in the near-surface target region was measured by means of an X-ray spectroscopy. The efficiency of the plasma energy transport to the target was determined via the crater volume measurement using the crater replica technique. The experimental results were compared with two-dimensional numerical simulations where the plasma dynamics was based on the one-fluid, two temperature model, including radiation transport in diffusive approximation and ionization kinetics. It was shown that the plasma expansion geometry plays an important role in the ablative plasma energy transfer into the target.