EFFECTIVE ATOMIC NUMBERS AND ELECTRON DENSITIES OF GEL DOSIMETERS FOR He, B, C, AND O HIGHLY CHARGED PARTICLES INTERACTION IN THE ENERGY RANGE 10 keV–100 MeV

Abstract

The radiological properties of different gel dosimeter formulations including six normoxic and four hypoxic polymeric gels, BRESAGE, PREAGE®, Fricke gel dosimeters, and water were investigated using SRIM code. The effective atomic number Zeff and electron density (Ne) for heavily charged particle interaction were calculated and performed for Helium (He), Boron (B), Carbon (C), and Oxygen (O) ion interactions in the energy range from 10 keV to 100 MeV. Variations of effective atomic number (Zeff) and electron density (Ne) with the kinetic energy of ions, (He, B, C, and O), were observed over the whole energy range for all studied materials. Variations of Zeff for He ion are up to 21%, 25%, and 20% for hypoxic and normoxic gels, Fricke gel, and PRESAGE gels, respectively. For other ions, variation is up to 34% for hypoxic and normoxic gels as well as Fricke gel, and 32% for PRESAGE gels. It is found that the maximum values of Zeff have been observed in intermediate energies between 1-10 MeV for all dosimeters, except for PRESAGE and PRESAGE® , where maximum values were observed in the relatively low energy range 10 – 100 keV. For effective atomic number relative to water, polymeric gels and Fricke gel showed better water equivalence with differences <7%, while PRESAGE and PRESAGE® showed high differences up to 17.5%, 22%, 21%, and 25% for He, B, C, and O ion, respectively. Gels found to be most relative to water are (Fricke, HEAG, and PAG), Fricke and HEAG), (Fricke and HEAG), and (Fricke, HEAG, and BANG-1) for He, B, C, and O ion interactions, respectively. Data reported here gives essential information about the interaction of different types of charged particles with different materials and could be useful in the energy range specified.