Impact of BaO on the gamma-ray shielding performance of lanthanum barium-borate glasses.

This study examined the gamma radiation shielding properties of test barium-lanthanum borate glasses having the composition (80 - x) B2O3-8TiO2-11ZnO-x BaO-1La2O3 (x = 26, 29, 32, and 35 mol%). The glasses are designated as Ba26La1, Ba29La1, Ba32La1, and Ba35La1, and were prepared from the melt-quenching method. The radiation shielding parameters, mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), half-value layer (HVL), tenth-value layer (TVL), mean free path (MFP), and effective atomic number (Zeff), were evaluated by using Phy-X/PSD software, at energy (0.015-15 MeV). The results of this study indicate that an increased amount of BaO in the glasses improves the attenuation property of the glasses. For example, Ba35La1 had the highest LAC value of 186.392 cm-1 at 0.015 MeV. This suggests that the Ba35La1 glass has very good absorption for low energy gamma rays. Ba35La1 exceeds many lead-free shielding materials and achieves a comparable attenuation value to lead-based shielding glasses values with respect to attenuation coefficients for specific lead-based glasses, with energies relevant to diagnostic photons. Ba35La1 is a great lead-free candidate for medical and industrial radiation shielding applications. Some properties of the shielding characteristics in Ba35La1 strengthened this claim such as, the greatest shielding efficiency over the total energy spectrum was manifested by Ba35La1 < 0.1 MeV due to the photoelectric region, coupled with the K-edge discontinuity at 0.037 MeV as a result of the Ba absorption edge; thus confirming the role high-Z modifiers had in enhancing the attenuation coefficient results within the region of interest.