EPR, OSL, TL AND SPECTRAL STUDIES OF PORCELAIN

Porcelain is one of a group of promising building materials for recons truction of dose from external gamma exposures. The type and lifetime of the recombination centres play an important role in the accuracy of dose assessment, especially if the accident occurred many years befor e laboratory measurements. The properties of the recombination centres have been investigated by optically stimulated (green) luminescence ( OSL), thermoluminescence (TL), phototransfered thermoluminescence (PTT L) and TL glow spectra. The investigations were carried out by TL meas urements following green light irradiation of porcelain pre-heated at various temperatures; three photo-transfer peaks were recorded at 110, 170 and 230 degrees C. Among them, the PTTL peaks at 230 and 110 degr ees C exhibited pre-dose sensitization. The Al and Ge centres observed by EPR in porcelain were investigated in conjunction with the sensiti zation of the 110 and 230 degrees C PTTL peaks. Copyright (C) 1996 Els evier Science Ltd