Enhancing the gamma-ray attenuation parameters of mixed bismuth/ barium borosilicate glasses: Using an experimental method, Geant4 code and XCOM software

摘要

In this paper, we scrutinize the availability of borosilicate glassy systems doped with mixed heavy metals as radiation shielding attenuators; for this purpose, a glass system [20SiO_2 + 54B_2O_3 +1NiO + xBi_2O_3 + (25-x) BaO], x = 5,10,15, 20 and 25 mol.%] was prepared using melt quenching procedures. The optical transmittance of the glassy specimens was measured in the ultraviolet-visible range to study the influence of bismuth oxide on the transparency. The density and molar volume of the prepared glasses were increased from 3.31 to 4.51 g/cm~3 and from 31.47 to 36.96 cm~3/mole, respectively, as the concentration of Bi_2O_3 increased from 5 to 25 mol%. Moreover, the radiation shielding parameters, such as the mass and linear attenuation coefficients, the total atomic and electronic cross-sections, the effective atomic number, the effective electron density, and the half value layer and tenth value layer of these glasses were experimentally obtained at gamma-ray energies of 0.662, 1.173 and 1.332 MeV. We compared the measured linear attenuation coefficients with those simulated via Geant4 code and computed by XCOM software to ensure the accuracy in the experimental data. For all the current glasses, we found that the maximum linear attenuation coefficient occurred at 0.662 MeV and lied within the range of 0.246-0.365 cm~(-1). We also found that the values of both the linear and mass attenuation coefficients increased as Bi_2O_3 concentration was increased. Additionally, we found that the half value layer for the prepared glasses was smaller for the low energy (0.662 MeV) than the other energies, which confirmed that thin glass samples can shield from low energy photons. In terms of the tenth value layer, we report that the glass sample that contains 25 mol% of Bi_2O_3 had the smallest TVL. According to the obtained results, it can be stated that the borosilicate glasses doped with mixed heavy metals (BaO and Bi_2O_3) appeared to be transparent to the visible range and have good gamma-ray shielding features.