Abstract. Theoretical aspects of gamma image formation based on the scintillation method with the use of solid-state silicon photoelectron multiplier and coding aperture are considered. The physical processes occurring in the scintillator under the action of ionizing radiation and leading to generation of visible radiation are discussed. The effective cross sections of the photoelectric effect, Compton scattering, and electron-positron pair generation are calculated depending on the gamma-quantum energy. Parameters of several scintillation crystals with different physical properties and gamma-ray attenuation efficiency are presented. Principle of operation of the coding aperture intended for formation of gamma image is considered, and ways of realization of its various configurations are described. A block diagram of a gamma-radiation visualization system providing high visibility and efficiency of gamma sources monitoring is proposed.

Keywords: gamma-visualization, SiPMT, scintillator, gamma-ray absorption, coding aperture

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