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Gas-filled proportional detectors of ionizing radiation often contain such elements as thin anode wire, which make them sensitive to external acoustic or vibrational impact. This study investigates such sensitivity for the case of the proportional γ-radiation detectors filled with high-purity xenon gas. The detector demonstrates a dependence of its signal noise on the external acoustic wave frequency, the character of which most likely depends on the design of the detector, i.e. on such parameters as diameter and tension strength of the anode wire, etc. To suppress the negative impact of acoustic noise on the characteristics of the detector, the detector digital signal is processed in a Field-Programmable Gate Array board. The authors investigate the algorithm of «time windows», which allows separating (filtering) low-frequency noise in the output signal of a gas-filled detector, which arises due to the influence of external sound, from the useful signal, i.e. the ionization pulses. This approach allows performing spectral measurements of γ-radiation with a significant acoustic noise background, when detectors with a conventional analog spectrometric channel cannot handle the task.

The results of a study of some ways to improve spectroscopy characteristics of the CdZnTe quasi-hemispherical detectors when working in high gamma radiation fluxes are presented. It was shown that the use of IR illumination with a wavelength of 1050 nm or 1200 nm or at slight warm-up of the detector to +30°C … +40°C can significantly improve spectroscopy performance of the CdZnTe detectors of size 3.5 mm × 3.5 mm × 1.75 mm when operating in a tested gamma-radiation field with a dose rate up to 590 mGy/h.

The influence of monochromatic optical stimulation with wavelengths from 400 to 1100 nm on the characteristics of CdZnTe quasi-hemispherical detectors was studied. It was found that illumination with infrared (IR) light with wavelengths of 870–900 nm close to the absorption edge of the CdZnTe significantly improves the performance of the detector at room temperature. Improvement can be achieved with low-intensity IR illumination at 1–300 \mu\ W depending on the chosen wavelength of illumination. Higher intensity illumination was observed to lead to the degradation of the detector's spectrometric characteristics. IR radiation was noted to influence the detector's sensitivity, changing the equilibrium between free and trapped carriers and improving charge collection. For practical purposes, the use of an IR light-emitting diode (LED) as the IR source is suggested. We tested various LEDs with light wavelengths of 770 to 1020 nm. The degree of improvement was different for different detectors due to the different source materials used in the detectors and their dimensions. For example, the performance of a detector that was 10 mm \times\,10 mm \times\,5 mm in size with an initial energy resolution (FWHM) of 14.9 keV at 662 keV was improved with an IR LED illumination of up to 8.6 keV. IR stimulation improved the spectrometric characteristics for a wide range of energies starting at 59.6 keV without decreasing detection efficiency and over the temperature range from - 30^\circ\ C to + 70^\circ\ C. We found that the use of IR illumination with a properly chosen wavelength not only improves the performance of detectors at low temperatures but also stabilizes them over time. [ABSTRACT FROM PUBLISHER]