Effective Method for Increasing the Peak SXR Power in Experiments on Implosion of Nested Arrays of Mixed Composition.

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]