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Information × Registration Number 0221U104873, 0120U102158 , R & D reports Title System for diagnostics of ZnSe crystals as detectors of ionizing radiation. popup.stage_title Head Degoda Volodymyr Ya., Доктор фізико-математичних наук Registration Date 25-04-2021 Organization Taras Shevchenko National University of Kyiv popup.description2 The object of research is physical processes in zinc selenide single crystals that cause current flow and recombination of free charge carriers, which are generated in a semiconductor during the absorption of X-ray quanta. The aim of the work is to conduct complex experimental studies of the conductivity and luminescence of ZnSe crystals to determine the possibility of their use as detectors of ionizing radiation. Research methods - X-ray conductivity and X-ray luminescence, phosphorescence and relaxation of conduction current, thermally stimulated conductivity and luminescence and their dose dependences at different intensities of X-ray excitation. When X-ray excitation is switched on in ZnSe single crystals, there is a delay in the excitation of X-ray conductivity in comparison with the excitation of X-ray luminescence at all temperatures and depends on the intensity of X-ray excitation. This phenomenon is due to the localization of free carriers on traps. The theoretical dependence of X - ray conductivity kinetics in the framework of a multicenter model for wide - band semiconductors is obtained, which well approximates the experimental results. The study of the conduction current of conduction at low temperatures can be used to diagnose semiconductor detectors for their operation in spectrometric mode. Studies of the kinetics of light accumulation in ZnSe single crystals have shown that the maximum accumulated light sum during X-ray excitation does not depend on the intensity of the excitation radiation. This means that the classical model of crystal phosphors with one type of traps, which gives the dependence n∞ ~ ex I for the maximum accumulated light sum, is too simplified. It is necessary to use a model of crystal phosphorus with several types of traps. Product Description popup.authors Doroshenko Iryna Yu. Kohut Yana Р. Losytsʹkyy Mykhaylo Yu. Pavlova Natalija Yu. Podust Galyna P. popup.nrat_date 2021-04-25 Close