Publication Date
Volume
1
Issue
2
Start Page
7
Abstract
An active assay system is defined as one that acts upon a nuclear sample to induce a measurable reaction. In contrast, passive systems (such as the gamma spectrometer) do not influence the sample, but measure the radiation naturally emitted by it instead. As a result of U.S.A.E.G.-sponsored programs within the past two years, a new class of nuclear measurement instruments has been developed: active assay systems using isotopic neutron sources. These systems, although certainly not a panacea for nuclear assay problems, promise to aid in the resolution of many of them.