Studies on γ-ray induced structural changes in Nd~(3+) doped lead alumino silicate glasses by means of thermoluminescence for dosimetric applications in high dose ranges

摘要

Thermoluminescence (TL) studies on PbO-Al_2O_3-SiO_2:Nd~(3+) glasses mixed with varying concentrations of Al_2O_3 exposed to y-rays of dose in the range 0-5.0 kGy were carried out. The TL emission exhibited a dosimetric peak at about 185 °C. The TL output under the glow peak increased with increasing Al_2O_3 and also with the γ-ray dose. The mechanisms responsible for TL emission and enhancement of TL output with increase in the concentration of Al_2O_3 were quantitatively discussed in terms of induced structural defects in the vicinity of Nd~(3+) ions due to interaction of y-rays with the glass network in the scenario of varying concentration of Al_2O_3. The dose response of these glass samples exhibited linear behavior in the medium dose range viz., 1.0-3.0 kGy. Finally, it is concluded that the glass containing the highest concentration of Al_2O_3 exhibits high TL output and such glasses are useful for dosimetry in the range 1.0-3.0 kGy and hence these glasses may be useful for dosimetry in such high range of doses required for commercial radiation processing of perishable food commodities to extend their shelf-lives.