|Budget Amount *help
¥7,400,000 (Direct Cost : ¥7,400,000)
Fiscal Year 1992 : ¥2,500,000 (Direct Cost : ¥2,500,000)
Fiscal Year 1991 : ¥4,900,000 (Direct Cost : ¥4,900,000)
For the confirmation of reliable thermoluminescence (TL) dating toward young age, some basic research has been developed from both aspects of TL-spectrometry using an image intensified diode array unit and the development of highly sensitive TL-measuring system.
In the former case, the file data, consisting of about 1 Mbite or more, from the spectrometric system were converted from binary into decimal code along with shortening data sizes. The final three dimensional TL-spectrum, comprising of wavelengths, temperatures, and TL-intensities, could be displayed as a contour map; one could easily recognize the change of TL-spectra for a variety of weak TL-specimens. Furthermore, the file data could be used for the presentation of glow-curves and spectrum in the desired wavelength and temperature regions.
In the latter, the simultaneous TL-measuring (IPDA) system in blue-and red-regions has been developed for the reliable gelogical age determination as well as archeological dating using two p
hoton-counting parts, a newly devised heater installed with a quartz glass and two ceramics heaters, and a computer as a system control part. The application of a light pipe between the heater and a photomultiplier extremely served the effective collection of weak TL-emission until several times in detection sensitivity. By using the present TL-measuring system, the kinetic parameters regarding a single TL-peak at 320ﾟC of the natural quartz grains were determined in both blue-and red-regions. The results after best-curve fitting procedure to glow-curves utilized for the evaluation of mean lives of the trapped electrons.
Moreover, the TL-properties were analyzed using both IPDA spectrometry and TLCI-method after thermally annealing treatment of originally blue-TL Z-cut quartz slices; an apparent color change from blue-to red-TL has unexpectedly occurred in some parts of slices after annealing treatment beyond 900ﾟC. This interesting result should suggested with respect of some information about causes of red-TL on natural quartzes, which has been initially found in our laboratory. Less