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The paper presents the results of experiments with the compression of the plasma of double multiwire arrays of mixed composition and the generation of powerful soft X-ray radiation (SXR) pulses carried out on the powerful electrophysical facility Angara-5-1 at a discharge current of up to 3 MA. Based on the latest experimental data on the production rate of different plasmas (in μg/(cm2 ns)) [1] and on specificities of the dynamics of plasma compression in nested arrays [2], a nested array was designed, which makes it possible to obtain a high SXR peak power in comparison with the optimal (in terms of radiation power) designs of single and nested tungsten wire arrays. By selecting substances with different plasma production rates, it was possible to reduce the level of magnetohydrodynamic instabilities at the final stage of compression of the inner array. This made it possible to reduce the radiation pulse duration and increase the SXR power. Using implosion of nested arrays of mixed composition, consisting of plastic fibers and tungsten wires, shorter and more powerful SXR pulses with a maximum peak power ~10 TW with a pulse duration FWHM ~ 5 ns were obtained, compared to the parameters of SXR pulses upon compression of single tungsten arrays: ~ 5 TW and FWHM ~ 10 ns. Thus, we have shown the possibility of a twofold increase in the peak SXR power during compression of nested arrays under the conditions of our experiments by optimizing their design. One of the results of this work was finding the optimal parameters of the nested arrays and the prediction of the peak SXR power for experiments at powerful electrophysical facilities, differing from with substantially different levels of discharge current, 4–26 MA (Angara-5-1, Julong-1, and ZR). [ABSTRACT FROM AUTHOR]

The generation of accelerated electron beams in a high-current Z-pinch formed by the implosion of wire cylindrical tungsten arrays on an Angara-5-1 facility is studied. The most intense characteristic and bremsstrahlung X-ray radiation of fast electrons is recorded from the central region of the pinch at the pin-ching stage. The transverse size of the radiation source in the characteristic tungsten radiation Lα is ~1.5‒1.8 mm, which is close to the transverse size of the radiation source in the soft X-ray emission (1‒1.5 mm). The current of accelerated electrons generated during the implosion of the wire array and the formation of a pinch is on the order of the Alfvén current (IA). This result is consistent with the estimate of the current of accelerated electrons made from the measured characteristic radiation intensity Lα of tungsten under the assumption that the mean free path of fast electrons in a pinch is on the order of its length. [ABSTRACT FROM AUTHOR]

Experiments on the acceleration of a flyer by a magnetic field make it possible to study the dynamic characteristics of matter on submicrosecond time scales. Megabar pressures at the Angara-5-1 facility are produced using the magnetic field of the current with a linear density of up to 5 MA/cm. In the previous experiments on the acceleration of a duralumin flyer, velocities of up to 10 km/s were achieved. The flyer motion was recorded by means of laser shadowgraphy. In this work, the efficiency of momentum transfer from a duralumin flyer to an initially immobile tungsten target was studied. From the kinematic parameters of the flyer motion before the impact and the motion of the flyer together with the target after the impact, the fraction of the flyer mass that transfer the momentum to the target was estimated. It is established that almost the entire mass of the flyer is involved in the impact process. [ABSTRACT FROM AUTHOR]

By means of the electrostatic expansion of a cylindrical wire array by an additional electrode, quasi-spherical arrays with a radius of 8–12 mm and a mass of 200–400 μg consisting of 30–60 tungsten wires 6 μm in thickness are formed. The compression of Z pinches formed by these arrays was performed by a current of 3–4 MA with a rise time of 100 ns in the Angara-5-1 facility. It has been shown that the central part of this array forms a region hotter than its edges and that for cylindrical arrays. [ABSTRACT FROM AUTHOR]