Systematic Comparison of Photon Interaction Cross-Sections from Low-Z to High-Z Materials Using Dominance Graphs for Gamma-Ray Shielding

This study presents a systematic and comparative analysis of photon interaction cross-sections for a representative set of materials spanning low-Z to high-Z regimes, aiming to improve the interpretability of gamma-ray shielding performance across different energy domains. Although extensive cross-sectional data are available in databases such as XCOM, most studies focus on individual materials or tabulated values, offering limited insight into the relative dominance of photon interaction mechanisms over wide energy ranges.In this work, total and partial attenuation coefficients—including photoelectric absorption, Compton scattering, and pair production—were obtained from the XCOM database for selected materials (B, Al, Si, Cu, W, Pb, water, and air) over the energy range of 1 keV to 20 MeV. These materials were not selected arbitrarily; they represent commonly used shielding and structural materials across nuclear, medical, aerospace, and industrial applications, enabling physically meaningful and application-relevant comparisons. A dominance-based visualization approach was developed to normalize and compare the relative contributions of photon interaction mechanisms across different materials.The results reveal systematic transitions between interaction regimes as a function of photon energy and atomic number. Low-Z materials are primarily governed by Compton scattering over a broad energy range, whereas high-Z materials exhibit dominant photoelectric absorption at low energies and increasing pair production at higher energies.Rather than generating new data, this study provides a comparative and visually interpretable framework for analyzing existing cross-sectional datasets. The approach facilitates a clearer understanding of photon–matter interactions and supports the preliminary selection of materials for gamma-ray shielding applications, particularly in multilayer or composite systems.