Experimental determination of X-ray absorption and K-edge behavior in metal foils

Abstract

This study investigates the absorption behavior of X-rays in various metallic foils, focusing on the dependence of transmitted intensity and mass attenuation coefficients on material thickness and radiation wavelength. The objective was to experimentally validate theoretical models of X-ray attenuation and to determine the position of K absorption edges for selected elements. Using a goniometer-based X-ray setup equipped with a Geiger-Müller counter, a series of measurements were conducted on aluminum, zinc, tin, copper, and nickel foils under controlled conditions. The first part of the experiment demonstrated an exponential decrease in transmitted intensity with increasing absorber thickness. The second part established a cubic dependence of the mass attenuation coefficient on the wavelength of the incident X-rays, consistent with theoretical expectations for photoelectric absorption. In the third part, distinct K absorption edges were successfully identified for copper and nickel, with experimentally determined edge energies closely matching known values. The results confirmed that materials with higher atomic numbers exhibit greater absorption and sharper K-edges. Minor deviations observed near absorption thresholds were attributed to spectral interference and detector resolution limitations. Overall, the study validated key theoretical relationships and demonstrated the effectiveness of the experimental setup for accurately characterizing X-ray absorption behavior in metals.