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An Automated Ionization Chamber for Secondary Radioactivity Standards



Ryan P. Fitzgerald


We report on the operation and characterization of a new ionization chamber system, called AUTOIC, featuring a commerical digital electrometer and a commerical robotic sample changer. The ralative accuracy of the electrometer was improved significantly beyond the manufacturer's specifications through an in-house calibration of the various ranges, applied via software. The measurement percision and repeatability of the system have been determined by measuring multiple samples of the same radionuclide over the span of two or three years. The linearity of the system was examined by following the decay of Tc-99m, Mo-99 and Xe-133 sources for up to 19 half-lives and determining half-life values. All of these values agree with the accepted literature values, within their combined, small, uncertainties.
Applied Radiation and Isotopes


ionization chamber, radioactivity


Fitzgerald, R. (2009), An Automated Ionization Chamber for Secondary Radioactivity Standards, Applied Radiation and Isotopes (Accessed April 21, 2024)
Created December 8, 2009, Updated February 19, 2017