RESUMO
A bilateral comparison to determine the activity concentration of the same 125I solution was organized. As electron-capture radionuclide with a rather high atomic number, 125I must be regarded as difficult to measure. The situation is partly exacerbated by the fact that some established standardization methods, like photon-photon coincidence counting, can no longer be applied due to the unavailability of appropriate equipment and expertise. One aim of this work is to compare modern liquid scintillation counting methods for the standardization of 125I. Both participating metrology institutes have used their custom-built triple-to-double-coincidence ratio (TDCR) counters and the determined activity concentrations are in excellent agreement even though the ways to analyze the data and to compute counting efficiencies were widely independent. The results also agree with the outcome of 4π-γ counting that was carried out at LNHB. In both laboratories, the measurements were complemented by measurements with several secondary standardization methods which even allow to establish a link to the CCRI(II)-K2.I-125(2) comparison started in 2004. A good agreement between the TDCR results and the key comparison reference value of the 2004/2005 comparison was obtained.
RESUMO
A program has been set up to calculate the K- and L-Auger electron emissions resulting from the radioactive disintegration process, and to study all the possible emissions in detail. Due to the fact that only a small number of experimental results are available in the measurements of K- and L-Auger electrons, the calculated values obtained in this work were compared with the other calculated values available. Good agreement was found between the values. Some of the results are given as examples.
Assuntos
Elétrons , Modelos Químicos , Radioisótopos/análise , Radioisótopos/química , Radiometria/métodos , Simulação por Computador , Transferência de Energia , França , Guias como Assunto , Meia-Vida , Doses de Radiação , Radioisótopos/normas , Padrões de Referência , Valores de ReferênciaRESUMO
In order to disseminate information about decay data and their evaluation, as well as other topics in the field of ionizing radiation, the Bureau National de Métrologie-Laboratoire National Henri Becquerel (BNM-LNHB) has published a website. Most of the web pages are concerned with the international working groups in which the BNM-LNHB takes part. In particular, a library of uranium and plutonium spectra is now available, as well as the results of evaluation of decay data of nuclides of special interest.
