COMPUTATIONAL EVALUATION OF ALPHA-PARTICLE STOPPING POWER AND RANGE IN SELECTED MATERIALS

Abstract

The interaction of alpha (α) particles with matter is investigated through a comprehensive computational evaluation of stopping power and penetration range in selected gaseous, liquid, and solid materials. Using the Bethe–Bloch formalism with appropriate corrections, stopping power values were computed for α-particle energies between 0.5 and 9.5 MeV and benchmarked against SRIM–IAEA reference data. The results show a systematic decrease in stopping power with increasing particle energy across all materials, confirming the inverse dependence on particle velocity. High-density and high-atomic-number materials such as gold and lead exhibit markedly higher stopping power and rapid energy attenuation, while low-Z materials, particularly hydrogen and air, show minimal energy loss and permit extended particle ranges. Materials such as aluminum, silicon, germanium, and water display intermediate behavior, reflecting their moderate electron densities. Range calculations reveal that α-particle penetration increases with energy in all materials but remains strongly material-dependent, with extremely short ranges in dense metals and significantly longer ranges in gaseous media. These findings provide useful insight for applications in radiation shielding, dosimetry, detector design, and radiological safety analysis.