Radiation defects in solid matrix as a physical base of EPR-dosimetry. The results of international experiment 'Intercomparison'

Full text: The very high sensitivity of EPR method at radiation defects in solid matrixes registration caused for last decade an intensive development of a new field - EPR-dosimetry. The suitable work substances had been found in a result of prolonged wide investigations, that allowed successful development both an operative dosimetry, and, that is especially important, the retrospective one. Nowadays the retrospective dosimetry on tooth enamel is adopted by IAEA and WHO as the main method of the radiation accidents consequences analysis for suffered population. In the report the methodical peculiarities of EPR-dosimetry are reviewed, the possible sources of the dose characteristics nonlinearity occurrence are analyzed as well other sources of errors and the ways of their elimination are considered. The review of the results of the international experiments 'Intercomparison' on EPR-dosimetry on tooth enamel series, held for last years under IAEA aegis is given. Practically all leading worldwide labs, including NMR laboratory of the INP NNC RK, took part in these experiments. The main goal was estimation of accuracy, sensitivity and reproducibility of summary dose values, having been reconstructed on base of EPR-signal of radiation defects in tooth enamel. The last experiment 'Intercomparison 3' has shown a considerable progress achieved lately in this area. Now the Japanese scientists from Hiroshima are preparing a further continuation of these Intercomparisons. Researches of radiation-induced EPR signals, stabilized in solid matrix, have been found out also rather useful and productive for the purposes of geological and archaeological dating, in criminalistics, in radiation chemistry and so on. Probably, this method will be rather perspective and at identification of radiation-sterilized food-stuffs, which come up now on world markets more and more often, however, studies in this direction are still on an incipient stage only