Experimental Evaluation of Accuracy in Determining the Direction to a Pulsed Source of Gamma-Radiation by a Spherical Absorber With CdTe Detectors in a System of Nuclear Situation Monitoring

The necessity and possibility of creating a dosimetric channel for determining the direction to the source of penetrating gamma-radiation in the nuclear situation monitoring system have been substantiated. The experimental assessment of a reduced error of the device for determining the direction to pulsed sources of radiation using a spherical absorber and CdTe detectors was carried out. These detectors can be used effectively only if there is appropriate electronic equipment, constructed in accordance with their characteristics and spectral-temporal characteristics of highly intense pulsed radiation. The direction to high-intensity pulsed radiation of linear accelerator Varian Clinac 600C (USA) by telluride-cadmium detectors was determined in the pulsed mode. This allowed conducting an experiment to determine the dependence of the coefficient of proportionality of recording pulses from each detector on the angle of direction to the source of pulsed radiation of the linear accelerator. A reduced error was assessed by comparing the received experimental data with a theoretical dependence based on a physical and mathematical model. It was recommended to divide the entire range of angles from 0° to 360° into five sub-ranges, in which three or two proportionality coefficients are responsible for determining the angle in space on gamma sources. The maximum reduced error does not exceed 10 % and the maximum angle error is not more than 8.4°. The most accurate determining of the angle to a radiation source can be carried out in the presence of a theoretically calculated and experimental database of proportionality coefficients for all angles in space and energy of radiation sources