|Fig. 1: Soliders take part in multi-agency nuclear forensics exercise. (Source: Wikimedia Commons)|
Nuclear forensic analysis is the process of determining the key characteristics of nuclear material of unknown origins.  This process is specifically helpful in the event of a nuclear explosion and identifying all information necessary for attribution, the final stage of nuclear forensics analysis that identifies the origin or expected route of nuclear material. As a method of gathering intelligence, nuclear forensics is useful with respect to issues of national security. Because nuclear material is created by uranium mining or neutron capture, the process helps security agencies identify, intercept, preempt, and even deter terrorist attacks from occurring.  Fig. 1 depicts the role the military can play in the investigation process in conjunction with agencies like the FBI, CIA, and NSA.
There are various analytical techniques used in forensic investigations. The most common are chemical and physical analytical methods like secondary ion mass spectrometry (SIMS) and scanning electron microscopy (SEM).  With respect to nuclear forensics, SIMS techniques are microanalytical that provide elemental and isotopic information of samples that are either small or inhomogeneous.  SEM techniques, microstructural in nature, are most successful with inhomogeneous and powders, providing a surface area image of the sample. This technique specifically uses high beams of electrons that may reveal information about morphology, particularly helpful in identifying the production process of the nuclear material. 
© Bryant Johnson. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
 K. Mayer et al., "Nuclear Forensics: A Methodology Applicable to Nuclear Security and to Non-Proliferation," J. Phys. Conf. Ser. 312, 062003 (2011).
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