Experimental Determination of Effective-Z from the Measurements of Gamma-Ray Buildup Factors

Abstract

Buildup factors B_N for the number of gamma-rays in C, H₂O, Al, Cu and Pb absorbers have been measured and the variation of B_N with the atomic number Z and the thickness of the absorber were investigated. Linear absorption coefficient and the buildup factor of a soil sample were measured and the effective-Z (Z_eff) of the sample was estimated from B_N versus Z curve. The soil sample was also analyzed for its constituents to evaluate its absorption coefficient and the Z_eff was re-determined. The results obtained using these two methods were compared and they were found to be in good agreement.