A Machine Learning Method for the Forensics Attribution of Separated Plutonium

Interrogating a Mixed Actinide Basket Using High-Resolution γ-Ray Spectrometry: A Nuclear Forensic Perspective on Possible Smuggling Scenarios

“…For example, in the IAEA database, the majority of the reported incidences involve trafficking of a small quantity of fissile or other radioactive materials, raising concerns about the spreading of radioactivity in the environment. Nuclear forensics, a multidisciplinary branch of analytical science, can play a key role in strengthening safeguard capabilities and ensuring global nuclear security by deterring diversion incidences, even in very small quantities, and providing sufficient evidence on the origin and intended purposes in case of a seizure, that may be useful for legal proceedings. − With the advent of advanced analytical methodologies and improved computational capabilities, the branch of nuclear forensics has witnessed rapid development in the recent past and has been able to solve challenging forensic problems using experiments and artificial intelligence/machine learning techniques. − …”

In View of “On-Site” Nuclear Forensics and Assay of Fissile Materials in Sealed Packages by High-Resolution γ-Ray Spectrometry

“…Since the early 1990s, numerous incidences of nuclear smuggling, globally, have been reported in the IAEA’s Incident and Trafficking Database (ITDB), which required a rapid development of a field, “nuclear forensics”, in the past few years. − Nuclear forensics is the identification, characterization, and assay of special nuclear materials (SNMs) diverted from regulatory control to provide support for nuclear attribution and legal proceedings. Numerous advanced analytical methodologies have been evolved in the recent past to address complex nuclear forensic problems using experiments (majorly destructive analysis) and artificial intelligence/machine learning techniques. − For the samples mostly encountered in nuclear forensics, prior information about the nature of the sample and its contents is not known, and thus, nondestructive γ-ray spectrometry can play an important role in fairly rapid harvesting of information about the isotopic composition and their absolute amounts present in a sealed voluminous sample, without altering the physical integrity or the chemical form of the sample, thereby helping in quick “on-site” decision making regarding the severity, potential radiological threat, and possible intended use of the diversion. , This would assist in setting up the roadmap for the next steps of analysis for more detailed nuclear forensic investigations. Modern high-purity germanium (HPGe) detectors with high resolution can resolve isotope-specific characteristic γ-rays and thus can provide isotopic fingerprints of different radionuclides present in a sealed sample. ,− γ-ray spectrometers are used globally to detect and deter nuclear smuggling across borders and ports, where the objective is mainly a rapid screening of a large number of freight and personnel for SNMs or other radioactive species without aiming for precise assay. , With the advent of high-efficiency handheld γ-ray spectrometers with moderate to high energy resolution, detailed assay of fissile isotopes such as 239 Pu and 235 U in suspected flagged packages may be feasible, on-site, with a measurement time of few minutes to an hour.…”