Features of X-Ray Spectra of Copper in Laser Plasma and a Hybrid X-Pinch

The results of studies of the copper spectra in the soft X-ray range in two fundamentally different (they differ in the heating method) high-temperature dense objects with high energy densities, laser plasma and a hybrid X-pinch, are presented. The uniqueness of the conducted experiments is that both sources were created at the Lebedev Physical Institute, Russian Academy of Sciences (FIAN), and are currently actively operating. The use of the same measuring equipment, which was also invented at FIAN, in these experiments made it possible to completely eliminate the influence of the conditions for observing and recording spectra on the obtained results. Calculations of the spectra have been performed using the radiation–collision model, from which it follows that only if a large number of transitions followed by averaging the obtained numerical results are taken into account, the results can be compared with the experimental data. It has been shown that it is necessary to take not only the plasma temperature and density into account when comparing the theory and particular experimental results, but the plasma size and shape must also be considered. Only in this case, it becomes possible to simulate the experimentally obtained results with satisfactory accuracy. In this case, it is possible to obtain information on the size of the emitting plasma region, which was never done previously.