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Wacker, John F

Publications and source records attributed to Wacker, John F.

Isotopic Measurements: Interpretation and Implications of Plutonium Data

One of the fundamental activities within the field of nuclear forensics is the laboratory analysis of nuclear material; one aspect is providing the isotopic composition of the material under investigation. For both plutonium and uranium, this includes a unique suite of isotopes that, individually and collectively (i.e. an isotopic vector), will help characterize these materials, and potentially provide insight into their mode of production, intended utilization, and processing history. A full understanding of how this information is used provides the basis for defining the need for these measurements and helps determine the precision and accuracy requirements for those measurements. This paper provides an overview of this process as it applies to plutonium, discussing how reactor design and operating parameters can impact the resultant plutonium vector, thereby giving us the ability to infer those reactor traits based on isotopic measurements.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Nuclear Forensics: A Holistic Overview

Discussions of nuclear forensics are often restricted to work performed by radio-chemists measuring nuclear material attributes in the laboratory. However, this represents only one portion of the work required to answer critical questions. Laboratory analysis results in measurements that need to be evaluated. The results of those evaluations must be put into their proper context in order for them to be useful to others and often require merging those results with additional information. This may contribute to attribution, by virtue of inclusion or exclusion. Finally, the end product must be presented such that appropriate actions can be taken. This could include prosecution by law enforcement, policy initiatives on the part of legislative bodies, or military action in the case of nuclear attack (whether that attack is preempted or not). Using the discovery of a sample of plutonium during cleanup activities at Hanford in 2004, we will step through the process of discovery (representing an interdiction), initial field analysis, laboratory analysis, data evaluation and merging with additional data (similar to law enforcement and/or all source), thereby providing an example of an integrated approach.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

A CONCEPT FOR NATIONAL NUCLEAR FORENSIC LIBRARIES

The interpretation of data from the nuclear forensic analysis of illicit nuclear material of unknown origin requires comparative data from samples of known origin. One way to provide such comparative data is to create a system of national nuclear forensics libraries, in which each participating country stores information about nuclear or other radioactive material that either resides in or was manufactured by that country. Such national libraries could provide an authoritative record of the material located in or produced by a particular country, and thus forms an essential prerequisite for a government to investigate illicit uses of nuclear or other radioactive material within its borders. We describe the concept of the national nuclear forensic library, recommendations for content and structure, and suggested querying methods for utilizing the information for addressing nuclear smuggling.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗