## Materials and Methods
### Spectral Energy Measurements  
Photoelectric measurements of the device's radiation characteristics were carried out using a calibrated set of photodetectors as part of a \"Spektr-01K\" photoelectronic converter (FEC), which provides radiation detection in narrow spectral ranges of the UV, visible, and near-IR regions [49]. Signals from the FEC were recorded with a Tektronix TDS-2014C digital oscilloscope (bandwidth, 70 MHz). The oscilloscope was set to the signal-averaging mode over 64 pulses. The time-integrated emission spectra of the apparatus were studied using a Solar S100 wide-range fiberoptic spectrometer with a diffraction grating of 300 lines/mm and an S8378-1024 image sensor (manufactured by Hamamatsu, Hamamatsu City, Shizuoka Pref., Japan). The spectral sensitivity range of the spectrometer was 200...1100 nm; the spectral resolution was 1.5 nm. To register the absolute values of the spectral energy irradiances generated by the device at different distances, we used an Ocean Optics P300-1-SR quartz optical fiber (\(\O\)300 \(\mu\)m, \(\Delta\lambda\) = 200...1100 nm) together with a CC-3-UV-S cosine corrector (\(\Delta\lambda\) = 200...2500 nm). The exposure time of the spectrometer was set based on the condition of recording the distribution of energy irradiance averaged over 40 pulses. In terms of spectral sensitivity, the joint calibration of the optical system of the spectrometer with an optical fiber and a cosine corrector was carried out using a reference radiation source: DH-3P-CAL (manufactured by Ocean Optics). Figure 2 shows the time dependence of the spectral radiation intensity of the \"Zarnitsa-A\" apparatus in the short-wave UV region of the spectrum (\(\lambda\) = 257 \(\pm\) 14 nm), which was obtained by processing signals from the Spectr-01K FEC and the results of its integration over time. The thickness of the lines shows the value of the scatter in the values of the measured optical characteristics in 10 different turning cycles on the apparatus, with 64 pulses each. The spread of pulse energies did not exceed 10%. The duration of the UV-C radiation pulse at half-height was 20.0 \(\pm\) 0.5 \(\upmu\)s. This duration corresponds to the characteristic duration of the energy input to the discharge, which, with an energy of 20 J stored in the capacitors, provides the peak electric power of the lamp at \(\sim\)1 MW. Similar signal processing from the FEC \"Spektr-01K\" in other spectral ranges made it possible to reconstruct the photoelectronic radiation spectrum of the device and determine the energy-power characteristics of the irradiator integral over the spectrum, which amounted to a radiation power of 31.5 \(\pm\) 0.1 kW/sr and an angular energy density radiation in the spectral range of 200...1100 nm 0.77 \(\pm\) 0.02 J/sr. At the same time, up to 40% of the total radiated power and ~25% of the integral radiation energy were emitted in the UV region of the spectrum, \(\Delta\lambda\) = 200...400 nm. A decrease in the energy efficiency of UV radiation compared with power efficiency is associated with longer light pulse durations in the visible and near-IR spectral regions than in the UV range. The photoelectric measurement data were in good agreement with the results of spectrometric studies performed using the Solar S100 spectrometer. Figure 3 shows the radiation spectrum of the \"Zarnitsa-A\" apparatus's irradiator, as recorded by the Solar S100 spectrometer. The spectrum is provided as a dependence of the spectral energy density of the radiation (E\({}_{\rm s\lambda}\)) on the wavelength (\(\lambda\)) for one irradiation pulse at a distance of L = 50 cm from the irradiator cutoff of the apparatus. The emission spectrum of the device was predominantly continuous, with powerful lines of atomic and ionized xenon superimposed on it in the short-wave UV region (200...300 nm) and the visible (420...550 nm) and near-IR (800...1000 nm) ranges.