An extensive investigation on gamma-ray and neutron attenuation parameters of cobalt oxide and nickel oxide substituted bioactive glasses

This study aimed to investigate the gamma-ray and neutron attenuation parameters of cobalt oxide and nickel oxide substituted ten bioactive glasses. The mass attenuation coefficient (mu/rho) for the selected bioactive glasses was calculated using MCNPX code in photon energy range (0.02 MeV - 20 MeV) and the results were compared with the output of WinXcom software. Other vital gamma-ray attenuation parameters such as half value layer (HVL), tenth value layer (TVL), mean free path (MFP), effective atomic number (Z(eff)), and effective electron density (N-ei) for the selected bioactive glasses were also calculated for each approach. Gamma-ray and neutron transmission factors as well as neutron effective removal cross-sections of each bioactive glass (Sigma R) were also taken into consideration to underline the distinctive parameters. Additionally, exposure buildup factor (EBF) values were found with G-P fitting approach depending on the energy and penetration depths. The results points that, the lowest HVL, TVL and MFP values and the highest neutron effective removal cross-sections (Sigma(R)) values are the characteristics of NiO-4C and CoO-4. The results indicate that the density of the material affects the photon and neutron interaction parameters. While NiO-4C has the lowest TF values for both gamma and neutron radiation, the highest Sigma(R) values are collected from NiO-4C glass material. The gamma and neutron transmission factors (TF) of the studied bioactive glasses support the aforementioned results. The lowest Z(eff) values were generated for 45S5C and 45S5 ordinary glasses, while CoO-4 and NiO-4C doped glasses are having the highest values of Z(eff). EBF values of the glasses were also calculated in the energy range 0.015-15 MeV up to 40 mfp. The smallest EBF values were measured for CoO-4 and NiO-4C glasses. It can be concluded that NiO-4C bioactive glass outperformed compared to other studied samples and is a promising bioactive glass for gamma-ray and neutron attenuation.