Calculation of the Penetration of Gamma Rays Through Slabs by the Method of Invariant Imbedding

Abstract

The method of invariant imbedding has been applied to the problem of penetration of gamma rays through slabs. The accuracy of the method was examined by comparison with other reliable calculations and proved to be competitive with other well-developed methods. The method has the advantages that it is much more efficient than the Monte Carlo method and that it is readily applicable to the multilayer problems. An extensive series of calculations on the transmission of gamma rays through homogeneous slabs was carried out. The energy and angular distributions of transmitted photons from monoenergetic and oblique sources were obtained for slab thickness up to 15 mean-free-paths and for 7 materials. The results of calculations were compared with experiments and found to be in good agreement.