Amorphous barium borophosphate materials doped with small quantity of terbium ions and with the addition of some amounts of alumina were prepared. Thermo-luminescence (TL) characteristics of these glasses were investigated after irradiating them with different doses of y-rays. The TL emissions exhibited a dosimetric peak at about 210 deg C. The TL output under this glow peak is observed to increase with the y-dose. For any fixed y-ray dose, the TL output is increased with increase in Al2O3 content up to 3.0 mol%, and beyond this concentration, quenching of TL is visualised. The dose response of TL output of these glasses exhibited linear behaviour in the dose range 0.5-4.0 kGy. The mechanisms responsible for TL emission and the variation of TL output with the concentration of Al2O3 are quantitatively discussed in terms of structural defects induced during y-ray irradiation.
