OSL from BEO ceramics: New observations from an old material

In BeO ceramics, exposed to ionizing radiation, an intense OSL signal was o bserved. The properties of the signal and its behavior under various experi mental conditions were investigated. It was found that the OSL signal is a composite signal and exhibits strong thermal quenching. The quenching energ y was estimated as similar to 0.5 eV. The excitation spectrum of the OSL si gnal was obtained as a broad peak in the region 420-550 nm with maximum aro und 435 nm. The possible correlation between the OSL signal and the peaks i n the TL glow curve was also examined. It was interesting to observe that t he highly light sensitive TL peak near 220 degrees C does not contribute to the OSL signal. The OSL signal was found to originate from a trap near 340 degrees C. To check the possibility of using the material for radiation dosimetry the dose response and thermal stability of the OSL signal were also investigate d. The dose response was found to be guile linear up to similar to 10 Gy. T he thermal activation energy of the OSL trap was determined as similar to 1 .7 eV using isothermal annealing and heating rate methods thus proving the suitability for dosimetry. (C) 1998 Elsevier Science Ltd. Ail rights reserv ed.