Analysis of Water-Equivalent Materials Used During Irradiation in the Clinic With Xcom and Beamnrc

Abstract

The devices used in the departments of Radiology, Nuclear Medicine, and Radiation Oncology should check for precise dose at some periods. The purpose of study is to compare the materials used for dosimetric control using Monte Carlo (MC) simulation. For MC simulation, BEAMnrc and DOSXYZnrc were used. For photoelectric absorption and total absorption, XCOM was used. Five phantom materials were selected. These materials were PMMA, polystyrene, blood liquid, soft tissue, and water. The PDD's have calculated for each material by DOSXYZnrc. When Percent Depth Dose (PDD's) examined, we could see that the water and polystyrene behaved like soft tissue and blood. However, The PMMA material didn't match with water and other materials. As a result, dose distribution for any materials is independent of its atomic number. Density of material is more important for dose distribution at MV energies. For dosimetric control, density of material should be chosen close the water properties. PMMA material shouldn't use instead of water for dose control.