Suitability of Topaz Glass Composites as Dosimeters Using Optically Stimulated Luminescence Technique

Optically stimulated luminescence (OSL) dosimetry characteristics of topaz glass composites were studied. The purpose of this research was to find the suitability of topaz glass composites as a dosimeter using the optically stimulated luminescence technique. The pellets of topaz glass from Sabser mine, Skardu, Pakistan, were prepared with dimensions of 6.0 mm diameter and thickness of 1.0 mm, and they were sintered at 900 °C. Gamma, X-rays and beta doses were given to pellets from ⁶⁰Co/¹³⁷Cs, X-ray equipment (16.2 and 41.0 keV) and ⁹⁰Sr/ ⁹⁰Y source respectively. The OSL decay curve revealed to be exponential with a rapid decay of signal within 10 s, presenting then a non-zero long tail. There is also an exponential decay for various absorbed doses in case of beta radiation. The integrated area of OSL signal versus absorbed dose showed a linear behavior from 100 mGy to 5 Gy for gamma and X-rays. This area after irradiation with effective energies of 16.2 keV is 1.6, 3.2 and 3.3 times higher as compared to X-rays (41.0 keV), ⁶⁰Co and ¹³⁷Cs respectively. There was no significant variation in the integrated area of signal above 0.66 MeV. A maximum variation in integrated area of OSL signal of about ± 9% was observed after ten cycles of consecutive OSL measurements. The pellets remained mechanically stable during handling in all types of experiments. Topaz glass composites can be used as dosimeters by employing the OSL dosimetry technique.