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Improvements in the characterization of actinides targets by low solid-angle counting



David M. Gilliam, Andrew T. Yue


In a paper presented in the Proceedings of the 19th World Conference of the INTDS, 1998, the results of a blind comparison between groups at NIST and the IRMM showed excellent agreement in characterization of actinide targets by alpha counting with low solid-angle geometry. At that time the most accurate NIST results estimated an uncertainty of 0.03% for the solid-angle determination. The NIST Neutron Physics Group now has improved the accuracy of its solid-angle determination by about a factor of 4, based on an improved aperture design, improved metrology, and comparisons among very independent metrology techniques at NIST. Applications of this improved technology are expected to include improved NIST measurements of the free neutron lifetime and a possible recalibration of the NIST standard for neutron emission rate, NBS-I.
Journal of Radioanalytical and Nuclear Chemistry


actinides, alpha assay, characterization, efficiency


Gilliam, D. and Yue, A. (2014), Improvements in the characterization of actinides targets by low solid-angle counting, Journal of Radioanalytical and Nuclear Chemistry, [online], (Accessed April 18, 2024)
Created February 2, 2014, Updated November 10, 2018