TL dosimetry of natural quartz sensitized by heat-treatment and high dose irradiation

Abstract: The aim of this paper is to report the sensitization of the TL peak appearing at 270°C in the glow curve of natural quartz by using the combined effect of heat-treatments and irradiation with high doses. For this, thirty discs with were prepared from plates parallell to a rhombohedral crystal face. The specimens were separated into four lots according to its TL read out between 160 and 320°C. One lot was submitted to doses of 60Co radiation starting at 2kGy and going up until a cumulative dose of 25kGy. The other three lots were initially heat-treated at 500, 800 and 1000°C and then irradiated with a single dose of 25kGy. The TL response of each lot was determined as a function of test-doses ranging from 0.1 to 30mGy. As a result, it was observed that heat-treatments themselves did not produce the strong peak at 270°C that was observed after the administration of high doses. This peak is associated with the optical absorption band appearing at 470 nm which is due to the formation of [AlO4]° acting as electron–hole recombination centers. The formation of the 270°C peak was preliminary analyzed in relation to aluminum- and oxygen-vacancy-related centers found in crystalline quartz. [Copyright &y& Elsevier]