Study of the effectiveness of protection against gamma radiation using a multilayer hemispherical screen

modeling of the efficiency of multilayer screens for protection against gamma radiation is considered, and the main factors affecting the shielding efficiency, including the energy of gamma quanta, the radiation structure, the effect of scattered radiation accumulation, and the possibility of activating screen materials. The effectiveness of protecting devices from pulsed gamma radiation using multilayer hemispherical screens is investigated. A mathematical model is proposed for calculating the intensity of gamma radiation after passing through various types of screens.Three standard radiation sources (point, flat and cylindrical) are considered. The accumulation effect depending on the scattering of gamma quanta in the material is taken into account. The advantages of multilayer screens providing selective absorption and suppression of scattered radiation are analyzed. Data on the attenuation coefficients of various materials (lead, tungsten, concrete, water, polyethylene, steel) and their effect on the shielding efficiency are presented, as well as information on the propensity of materials to activate radioactivity. Based on the analysis carried out, various options for constructing two - and three-layer screens are proposed, taking into account both the absence and presence of active materials. Examples of layer combinations and recommendations for choosing materials depending on the gamma-ray energy and safety requirements are presented. Screens are modeled for a given source geometry and gamma radiation, the necessary layer thickness is calculated to achieve a given level of protection, as well as the weight of structures and the time of safe operation are calculated. The simulation results confirm the effectiveness of multi-layer screens and the importance of taking into account the accumulation effect to improve the accuracy of forecasting. Tabular and graphical data are presented, which are used to evaluate the effectiveness of a multilayer material.