Mathematical modelling of radiative properties of substances that are used as soft X-ray source materials for X-pinch

Theoretical and experimental studies of radiative properties of substances that are used as soft X-ray sources in X-pinch have been carried out depending on the plasma composition. Important features of the theoretical model, which can be used for complex materials, are discussed. It is shown that X-pinch radiative efficiency depends on the spectral coefficients for X-ray absorption and radiation of plasma produced by exploding wires, and the efficiency depends on materials the wires were produced from. The efficiency can be optimized by modifying the wire composition. Theoretical estimations of radiative efficiency are compared with experimental data that are obtained from measurements of X-pinch radiation energy yield using two exploding wire materials, NiCr and Alloy 188. Symmetric multilayer X-pinch, where W and Mo wires are used, is considered. Theoretical explanation of experimental phenomena is discussed basing upon W and Mo radiative spectra, Rosseland and Planck mean free paths.