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Transparent thermoluminescent alumino-phosphate‑sodium glass system of 15Al 2 O 3 -35P 2 O 5 -25CaO-25Na 2 CO 3 (all in mol%) doped with different concentrations of SiO 2 were prepared by conventional melt quenching technique. X-ray diffraction (XRD) studies checked the amorphous nature of the prepared glass. Fourier Transform Infrared (FTIR) of the glass system was investigated to find the effect of SiO 2 -dopant concentrations on the absorption spectra in comparison with that of bulk sample (without dopants). Direct and indirect energy band gaps (E opt ) were determined and found to be in the range of 2.47–3.65 eV for m = ½ and 2.24–3.3 eV for m = 2. Refractive index (n) for each E opt value vary from 2.42 to 2.55 and from 2.32 to 2.63 for the direct and indirect transition, respectively. Urbach energy values of the newly prepared glasses are found to be from 0.57 to 0.98 eV. In addition, effect of UV exposure on thermoluminescence (TL) sensitivity was also examined for APCNSi 5 (contains 500 ppm SiO 2 concentration) and a linear response to dose was obtained, indicating that this type of glass is promising as a TL dosimeter within the UV range. [ABSTRACT FROM AUTHOR]

The transparent thermoluminescent aluminum oxide-based glass of 15Al2O3-35P2O5-25CaO-25Na2CO3, abbreviated as APCN (all in mol%) doped with different concentrations of SiO2 from 0.0-500 ppm was prepared using a conventional melt-quenching technique. The TL sensitivities of the prepared glasses were investigated at 3 Gy γ-dose using a 60Co source and measured at a heating rate 10 C/sec. The highest TL intensity of the material doped with SiO2 was found at a concentration of 500 ppm (APCNSi5). Deconvolution of the glow curve from APCNSi5 resulted in four peaks at about 161, 194, 237 and 293 C with a Figure Of Merit (FOM) of 1.28%. The APCNSi5 specimen had the best dosimetric properties when compared with the other samples. Reproducibility, repeatability, dose-response curve and fading effect were checked for peak 3, which appeared at about 237 C. The results displayed that the APCNSi5 glass system was a low-Z material (Zeff ≈ 10), and had good reproducibility and good repeatability. Peak 3 showed good linearity over a dose range up to 20 Gy (R2 = 0.999) and sublinearity behaviour was found. The signal from APCNSi5 faded by about 11% after 2 days post irradiation, therefore it showed almost no significant loss. Such properties make the newly prepared glasses suitable for and highly recommended for use in γ-dosimeters. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]