Variation of optical band gap with radiation dose in PbO-B2O3 glasses

The effect of dose variation of gamma-irradiation on optical band gap of PbO-B2O3 glasses have been studied in the wavelength region from 200 to 1200 nm. Absorption of glasses in near ultraviolet/visible have been used to calculate the optical mobility gap and width of tail before and after irradiation. The decrease in transmission due to irradiation indicates the formation of colour centers and structural changes in glass matrix. The optical spectrum has been measured before irradiation and in 50 Gy-50 kGy absorbed dose range. (C) 2007 Elsevier B.V. All rights reserved.