Chemical Composition Dependence of Exposure Buildup Factors for Some Biological Materials
نویسندگان
چکیده
Exposure buildup factors for some tissues such as bone compact, Muscle striated, orange articulation wax, red articulation wax, nylon, PMMA and paraffin 2 have been computed using the five parameter geometric progression (GP) fitting method in the energy range of 0.01515.0 MeV, up to the penetration of 40 mean free paths (mfp). The variation of exposure buildup factors for all the selected tissues with incident photon energy at the fixed penetration depths has been studied, mainly emphasizing on chemical composition (equivalent atomic number) of the selected tissues. This change results from the dominance of different interaction processes in different energy regions and the chemical composition of different materials.
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