Techniques for Measuring the Parameters of X-Ray Transport in Closed Cavities and Determining the Time of Thermal Breakdown of Foils

Techniques are described that make it possible to measure the X-ray transport velocity in closed cavities, the time of radiation heating of foils, the radiation temperature, and the timing parameters of X-ray pulses in experiments at the ISKRA-5 facility. The methods are based on position-sensitive time-resolving (with a spatial resolution of 150 µm and a time resolution of 50 ps) measurements of X-rays in four narrow spectral regions of 0.2–1.0 keV using X-ray streak cameras, as well as on multiframe recording (with a frame duration of 100 ps, ​​a frame number of 10, and a spatial resolution of 30 µm). In the experiments the peak Planck temperature of the radiation was 110–150 eV in the irradiating target and 50–90 eV in the additional box and behind the foils; the X-ray transport velocity in closed cavities ranged from 0.5 to 13 mm/ns and the time of thermal breakdown of foils was in range of 50–550 ps.