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The Dose Rate calculator (DRc) is a software program written in Java that facilitates the calculation of dose rates and age determinations of materials, for use in palaeodosimetric dating methods. The program runs in a user‐friendly interface and provides a number of user‐controllable features. Dose rates are calculated using updated conversion and attenuation factors. This paper presents the basic principles that the software takes into account in its calculations.  相似文献   
2.
We present results of particle size and radioactivity analyses of sediment samples collected from five sites with different burial environments. The uranium, thorium and potassium concentrations in the five sample sets are shown to vary with particle size. The potential effects of the observed size-dependent variations on electron spin resonance (ESR) dating of tooth enamel are assessed using two hypothetical models. Our results show that any bias to relatively fine fractions could result in a significant overestimation of the total environmental dose rate, leading to an underestimation of the calculated ESR age.  相似文献   
3.
A combination of two autoradiography methods was applied to investigate the radionuclide distribution patterns in a range of different silices. We obtained greyscale images (β‐radiation) and α‐track patterns for qualitative assessment, and used a statistical approach to quantify the degree of uniformity of the radiation fields. It was found that almost all samples are poor in potassium, thorium and uranium, and that locally high concentrations are present only in dark‐coloured veins and inclusions. Statistical analyses reveal evidence of radionuclide clustering in more than half of the 21 specimens. Concerning thermoluminescence dating of burnt lithics, such gradients should be taken into account to improve precision and accuracy in cases where the external radiation is not strongly dominating for the sample under consideration.  相似文献   
4.
In this paper optical dating results for a range of British archaeological sediments are presented to illustrate the potential this method offers for archaeologists. The optical dating is shown to offer an absolute method for directly dating the deposition of sediments for an age range of approximately 1–300ka. Problems have been found with recuperation of the optically stimulated luminescence signal and insufficient bleaching at deposition of the sediment. A suitable correction method for the recuperation has been found and a method of identifying insufficient bleaching is suggested.  相似文献   
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