Experience in commission of the radiocarbon dating lab based on Carbosorb method in Tehran

Full text: The only available electrostatic accelerator in Iran is a 3 MV Van de Graff accelerator, which was installed in the early 1970s. Various ion beam analysis techniques, including PIXE, RBS, RBS-Channeling, ERDA, PIGE, NRA, and IBIL are being conducted with Microbeam at the laboratory. It partially fulfills analysis requirements of environmental, archaeological, and biomedical samples. By the way, the machine suffers from low emittance, high environmental radiation, and reliability issues due to its age. However, there is a strong need for more sophisticated mass and elemental analysis for advanced applied research. This includes C-14 dating and ion beam analysis with a focused ion beam at high lateral resolution. Analysis of aerosol samples, distribution of trace elements in biological samples, single ion irradiation of cells, analysis of historical manuscripts and paintings, identification of counterfeit objects are some of the social demands for this facility. To overcome the above-mentioned deficiencies, establish capacity building and develop human resources, Iran is determined to promote and develop ion beam analytical techniques and archaeological dating under the supervision of IAEA as a TC project. For this purpose, a tandem accelerator facilitated with AMS is considered for procurement. No doubt, C-14 dating is expected to provide reliable data on the archaeological wealth of more than 7000 years' Persian civilisation. Unfortunately, there is no active C-14 dating lab in the country. To establish a network and knowledge transfer to potential stakeholders and to explore Iranian cultural heritage by local sources, increased human capacity to perform radiocarbon analysis, and increased ability to get involved in scientific investigations, a C-14 dating lab based on carbosorb methods was commissioned and reported in this work. This report describes the experience in commissioning of the radiocarbon dating lab based on carbosorb method in Tehran. Its purpose is to: (a) validate the predefined procedures, (b) introduce the relevant commissioning equipment, and (c) report on significant experiences on sample preparation. The procedure of the sample preparation for carbosorb method includes acid-base degreasing, carbon isolation, oxidizing, and purification of the radiocarbon, followed by chemical conversion to a compound suitable for C-14 dating was achieved. The measurements on prepared standard, blank, test sample, and background counting would be reported. The homemade radiocarbon dating equipment and vacuum line have been installed. Statistical analysis, calibration, and interpretation of the results for age determination were achieved. Technical procedure of the carbosorb dating method, data evaluation, and interpretation were available. In brief, the routine use of C-14 dating based on the carbosorb method including sample preparation, analysis, and age determination is available. The lab would be used for human resource development and determining the authenticity of cultural heritage objects and materials. No doubt, transfer of skills and expertise of pioneering lab as well as hands-on training on radiocarbon dating methods and validation of the procedures is necessary to achieve the goals.