Study of gamma radiation shielding properties of $\mathbf{ZnO {-}{} \mathbf TeO }_\mathbf{2}$ glasses

Abstract

Mass attenuation coefficient $(\mu _\mathrm{m})$, half value layer (HVL) and mean free path (MFP) for $x\hbox {ZnO}{-}$(100${-}x)\hbox {TeO}_{2}$, where $x = 10$, 15, 20, 25, 30, 35 and 40 mol%, have been measured for 0.662, 1.173 and 1.33 MeV photons emitted from $^{137}\hbox {Cs}$ and $^{60}\hbox {Co}$ using a $3\times 3$ inch NaI(Tl) detector. Some relevant parameters such as effective atomic numbers ($Z_\text {eff})$ and electron densities ($N_\text {el})$ of glass samples have been also calculated in the photon energy range of 0.015–15 MeV. Moreover, gamma-ray energy absorption buildup factor (EABF) and exposure buildup factor (EBF) were estimated using a five-parameter Geometric Progression (GP) fitting approximation, for penetration depths up to 40 MFP and in the energy range 0.015–15 MeV. The measured mass attenuation coefficients were found to agree satisfactorily with the theoretical values obtained through WinXcom. Effective atomic numbers ($Z_\text {eff})$ and electron densities ($N_\text {el})$ were found to be the highest for 40$\hbox {ZnO}{-}$60$\hbox {TeO}_{2}$ glass in the energy range 0.04–0.2 MeV. The $10\hbox {ZnO}{-}90\hbox {TeO}_{2}$ glass sample has lower values of gamma-ray EBFs in the intermediate energy region. The reported new data on radiation shielding characteristics of zinc tellurite glasses should be beneficial from the point of proper gamma shield designs when intended to be used as radiation shields.