Investigation of X-Ray Self-Emission of Plasma of Targets Heated by High-Power Pulses of Soft X-Ray Radiation

Experiments aimed at investigation of X-ray self-emission of plasma of heated targets consisting of layers of different materials (Mylar, polypropylene, In, Sn, and Au) exposed to the action of energy flux of X‑ray radiation (the so-called energy exposure of the target) of up to 10 kJ/cm2 were carried out. A Z-pinch induced by implosion of a tungsten wire-array by current of up to 4 MA in Angara-5-1 facility was used as a source of high-power X-ray radiation. The temporal dynamics of intensity of self-emission of heated targets was studied. In the process, contribution of expanding layer of a material with high atomic number Z to self-emission of the target dominates that of a Mylar film with effective charge Zeff ≈ 4.5. It is demonstrated that the 1/e decay time of target emission depends on expansion dynamics of target plasma. The latter, in turn, depends on orientation of the layer characterized by high atomic number relative to the source of radiation. New data on spectral composition of self-emission of targets and its changes with time is obtained. This data is compared with the results of numerical simulation of target heating and scatter by means of RALEF-2D two-dimensional radiation gas-dynamic code.