Sources, components and calibration of paleodose were studied for proper evalua- tion of the paleodose of porcelain in thermoluminescence (TL) dating. In the TL dating of porcelain using the pre-dose technique, the β...Sources, components and calibration of paleodose were studied for proper evalua- tion of the paleodose of porcelain in thermoluminescence (TL) dating. In the TL dating of porcelain using the pre-dose technique, the β dose from the internal natural radiation in the body of porcelain is the first, the environmental dose the second, and the α dose negligible. Sample thickness of 0.2―0.5 mm was used in the paleodose calibration. For a porcelain sample of such thickness, the distribu- tion of β dose inside the sample was nonlinear when the sample (aluminium re- places porcelain in this experiment) was irradiated by a laboratory 90Sr-90Y β source. Therefore, the β dose used was only an average value. A distribution curve of β dose and the calculation of average β dose in the sample were obtained, according to the build-up and attenuation effects of β dose in the sample. The results showed that a sample thickness of 200 μm resulted in an average dose increment of about 4% compared to the surface whereas for a sample with a thickness of 400 μm, the average dose reduced by the same percentage, and that for a sample of 300 μm in thickness the average dose is equal to surface dose approximately. The average β dose in samples with various thickness can be obtained by the provided equations.展开更多
文摘Sources, components and calibration of paleodose were studied for proper evalua- tion of the paleodose of porcelain in thermoluminescence (TL) dating. In the TL dating of porcelain using the pre-dose technique, the β dose from the internal natural radiation in the body of porcelain is the first, the environmental dose the second, and the α dose negligible. Sample thickness of 0.2―0.5 mm was used in the paleodose calibration. For a porcelain sample of such thickness, the distribu- tion of β dose inside the sample was nonlinear when the sample (aluminium re- places porcelain in this experiment) was irradiated by a laboratory 90Sr-90Y β source. Therefore, the β dose used was only an average value. A distribution curve of β dose and the calculation of average β dose in the sample were obtained, according to the build-up and attenuation effects of β dose in the sample. The results showed that a sample thickness of 200 μm resulted in an average dose increment of about 4% compared to the surface whereas for a sample with a thickness of 400 μm, the average dose reduced by the same percentage, and that for a sample of 300 μm in thickness the average dose is equal to surface dose approximately. The average β dose in samples with various thickness can be obtained by the provided equations.
