Neutron activation of NIST surrogate post-detonation urban debris (SPUD) candidate SRMs

Despite their importance, there is a dearth of post-detonation nuclear forensics standard reference materials (SRMs) suitable for analysis traceable back to a national standard. Accordingly, the nuclear forensics community has requested SRMs be produced that mimic post-detonation fallout debris that include actinides, urban materials, fission products, and activation products. The National Institute of Standards and Technology (NIST), in partnership with the National Physical Laboratory and with support from the Federal Bureau of Investigation, have developed two surrogate post-detonation urban debris (SPUD) candidate SRMs to mimic the “rubble” of a city after an improvised nuclear device detonation. NIST SPUD samples were irradiated at The University of Texas TRIGA reactor, then analyzed via gamma-ray spectroscopy for short-lived, medium-lived, and long-lived fission and activation products.