Measurements of the Effective Atomic Numbers of Alloys using Thick-Target Bremsstrahlung Intensities

We have investigated the accuracy with which the effective atomic number (Z_eff) of an alloy can be measured using the intensity of the thick-target bremsstrahlung produced by low-energy electrons incident on the alloy target. The experiments involved 5 keV-electron beams incident on thick brass, Ni/Fe/Mo, C-276, and stainless steel targets. By comparing the data obtained using alloy targets to the data obtained using a high-purity aluminum target and data from a previous study performed by our group (in which the Z-dependence of thick-target bremsstrahlung was studied), the Z_eff values of the alloy targets were measured and compared to theoretical values. While the experimental Z_eff values of the stainless steel and Ni/Fe/Mo targets were in relatively good agreement with the theoretical values, the experimental Z_eff values of the brass and C-276 targets were not.