Fast Neutron Activation Analysis
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material. e high rates of most transuranic spontaneous ssion sources (like
Pu) of even a gram or less usually swamp any cosmic-induced background rate
(in comparison, kg quantities of natural uranium produce neutrons only on the
same order as that of the cosmic background). All other sources of neutrons are
generally from alpha-n production (energetic alpha particles fusing with light
elements) that generate single neutrons that will be uncorrelated in time. e
exploitation of the time-correlated neutron ux from the spontaneous ssion
of
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Pu is what is used for materials accounting (Nakae etal. 2014).
Historically, the standard method employed for the material accounting of
plutonium masses is to measu ...