Optimization of detector shield shape in radiometric testing of thick-walled products

To calculate geometrical parameters of a collimation device of radiometric defectoscopes designed for testing of thick-walled products, angular and energy distributions of a point isotropic gamma source radiation field in the detection area behind an infinite barrier simulating a tested item have been studied. Dry concrete was used as a barrier in calculations and water - during experimental test. Results of calculation of the detector shield thickness are given