Selection of elements of the detector unit of the system for measuring the coordinates of gamma radiation sources

Abstract

The article considers the current problem of creating modern, effective and reliable systems for monitoring the radiation situation and the operational search for nuclear radioactive materials and radiation sources that have come out of regulated supervision. A promising method of non-destructive testing using semiconductor detectors of ionizing radiation is used for radiation-environmental monitoring, prevention of the consequences of nuclear smuggling and determination of coordinates of ionizing radiation sources. The method for determining the direction to pulsed and constant sources of gamma radiation uses the ratio of the number of signals coming from the detectors located in the absorbers of a special geometric shape. The purpose of the article is to select the elements of the detector unit for the tool, which uses the method of absorption to determine the coordinates of the source of gamma radiation. The main attention is paid to the search for optimal characteristics of the material of the radiation absorber and the choice of the detector. The article analyzes the parameters of nuclear radiation detectors from different semiconductor materials, highlights and describes their characteristics. Analysis of experimental data and theoretical calculations allows us to assert that in the case of coordinateometry of gamma-radiation sources, a wide-gap semiconductor CdZnTe should be chosen as a detector material. For detectors of this type, the energy range is from 20 to 3000 keV, the operating temperature range is from -40 to +50 0С, and the energy resolution is of the order of several percent.