Comparison and further improvement of some luminescence dating methods using heating and light-illuminating excitation

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The reliable TL (thermoluminescence) and OSL (optically stimulated luminescence)-dating methods are realized using a single aliquot regenerative dose (SAR) method which is superior to a multiple aliquots additive dose (MAAD) method from aspect of requirement of a few of sample aliquots. In the SAR measurement, several repetitions of the luminescence measurements and artificial dosing under a fixed geometrical condition by an artificial radiation source. Such experimental conditions have been established by an automated luminescence measuring apparatus equipped with a small or a mini X-ray generator in our laboratory, because a serious limitation exists in Japan for a radioactive isotope (RI) source (amounting to 40〜50 mCi). The new automated luminescence measuring system which is applicable not only to BTL and OSL but also to RTL using the SAR method. The features of this system contain a cluster of ceramics heaters, and a glass core-rod as an effective luminescence detection. Practica … More lly, quartz and feldspar extracts, from nine Jomon pottery pieces, which were assumed to be used 3,500-6,000 years ago, were followed to four kinds of luminescence measurements, involving RTL, BTL, OSL, and IRSL (infrared stimulated luminescence), using the automated luminescence measuring system. On these results, the RTL-ages, calculated using the accumulated doses and annual doses were compared with other OSL-and IRSL-ages. Conclusively, the RTL-dating was confirmed to be most reliable dating-method when quartz extracts from burnt archaeological materials are available. Recently, the similar RTL dating was satisfactorily applied for younger burnt archaeological materials such as the roof tile pieces (Sairyuuji temple) and stones of ancient kiln (Saitama and Hokkaido). An advanced luminescence dating was approached from basic property search of TL-glowcurve in lower temperature region from liquid nitrogen temperature up to 0 ℃, combined with electron spin resonance (ESR) spectrometry. As a result, Al and OH impurities in quartz specimens were found to affect remarkably the TL-properties together with thermal annealing temperature and cooling rate. Less