Thermoluminescence α-Al₂O₃:C detectors (TLD-500K): Some results of a long-term testing

Anion-defective α-Al₂O₃:C single crystals, commercially grown in Russia as TLD-500K detectors, have been increasingly used for environmental radiation measurements. These detectors have attracted great interest because of their high sensitivity and simple annealing procedure. The application of TLD for routine measurements in environmental monitoring, involving storage periods which may extend up to one year, imposes strict requirements on the fading, the change in sensitivity with long periods of time and other characteristics of the dosimeters. Many of these properties of TLD-500K have not yet been completely investigated and need to be further explored. This paper presents some results of long-term testing of the detectors. The variation in sensitivity within the detector group as well as changes of the sensitivity with time and number of read-outs were estimated. All tests were made by using low doses of irradiation, adequate for environmental dosimetry.