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DOE OSTI · 2530336

FRAM Version 7.1’s Bias

Vo, Duc Ta [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000223229671)
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Abstract

The Fixed-Energy Response-Function Analysis with Multiple Efficiency (FRAM) code was developed at Los Alamos National Laboratory to measure the gamma-ray spectrometry of the isotopic composition of plutonium, uranium, and other actinides. For FRAM versions 4 and earlier, the reported uncertainties of the results come from the propagation of the statistics in the peak areas only. No systematic error components are included in the reported uncertainties. For FRAM versions 5 and 6, we examined the FRAM analytical results of both the archival plutonium data and the data specifically acquired for the isotopic uncertainty analysis project and found the relationship between the bias and other parameters. We worked out the equations representing the biases of the measured isotopes from each measurement using internal spectral parameters, such as peak resolution and shape, region of analysis, and burnup (for plutonium) or enrichment (for uranium). The resulting biases were included in the reported uncertainties of FRAM v.5 and v.6.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS97 MATHEMATICS AND COMPUTINGFRAMplutoniumSNMuranium

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Vo, Duc Ta [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)] (ORCID:0000000223229671). 2025-03-06. FRAM Version 7.1’s Bias. https://doi.org/10.2172/2530336

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