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The use of ionizing radiation in archeology
HORÁKOVÁ, Sandra
The methods using ionizing radiation for studying the archaeological artefacts have found an important place in the archaeology. The archaeologists using the ionising radiation are receiving far more comprehensive view into the past. The main area of this identification is the age of the objects, proving their authenticity and the composition analyses to determine the object origin. There is number of different methods, but for the archaeology only those methods that do not impair the subject investigated are taken into the account. This is a fundamental limiting factor for this area, as far as the monuments create an irreplaceable cultural heritage. There are number of modern methods in this area. However, not all of them are suitable for a certain material. Every method is usually suited for a narrow range of dedicated elements and limited range of ages only. This work is focused on the methods using ionizing radiation, which are the mostly used and typical for this field. Thus, the question is, whether there are any significant risks for the archaeological research in terms of the radiation protection. In order to clarify this issue, this material describes various methods and presents the results of practical measurements for the roentgen-fluorescent method. This method was selected due to its frequent usability by the archaeologists, and because the mobile analyser can be used in the field. The theoretical part of this report is focused on the basic knowledge about ionizing radiation, which is important for the understanding the issue. This is about the basic terms, such as radioactivity, ionizing radiation and its kinds, and radiation protection. In the context of radiation protection, the deterministic and stochastic effects of the ionizing radiation are outlined. The basic methods of protection against ionizing radiation and the biological effects of radiation on a human body are also described. Also the limits, embodied in the principles of radiation protection, are described. For the comprehensive overview, the radiation burden of the population is briefly described in the theoretical part of this material. The next part of this bachelor degree report is the methodology of the research, i.e., summarizes the overview of the selected methods, in which the ionizing radiation is used. Seven methods that are most commonly used and are typical for the archaeology are described. Practical measurement of the bachelor degree report presents the results of the roentgen-fluorescent analysis. Archaeological Institute of the University of South Bohemia use this method and specifically the mobile analyser Thermo Scientific NITON XL2 GOLDD. It is being used for a quantitative analysis of the samples with the primary source of low power mini roentgen tube 45 kV/W with silver anode. For the dose rate measurement from the NITON XL2 GOLDD meter, the FH-40-10 dose rate meter was used, borrowed from the nuclear power plant Temelin. Its range is 10 nSv/h - 1 Sv/h. Several items were selected for the measurement, such as the bronze sword, steel weight with the diameter of 4 cm and silver coin with the diameter of 1 cm. The measurement was accomplished after a contact application of the mobile analyser on the investigated subject, for the analysis of its composition. At the same time the dose input was measured by the FH-40-10 meter over the measured subject.
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