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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Kim Wei Chin, Rei Kimura, Hiroshi Sagara, Kosuke Tanabe
Nuclear Science and Engineering | Volume 196 | Number 7 | July 2022 | Pages 852-872
Technical Paper | doi.org/10.1080/00295639.2021.2018927
Articles are hosted by Taylor and Francis Online.
Past studies validated the feasibility of the photofission reaction ratio (PFRR) method using both Gaussian and bremsstrahlung photons to estimate the isotopic composition of nuclear fuel materials without relying on their self-generated neutron information. However, the current PFRR method cannot solve a multinuclide system with more than two nuclides because the instability of the inverse matrix increases with the addition of the number of nuclides. Thus, this research proposes a numerical method for solving the simultaneous equations of a three-nuclide system onto PFRR to estimate the isotopic composition of nuclides. The results show good reproducibility with all cases maintained within a 10% isotopic composition difference except cases 6 and 7 of the first two photon energy combination schemes with maximum composition differences of 15.6% and 13.9% for 10% actual composition, respectively. A 20% actual composition of case 5 for the second photon energy combination scheme has a deviation of 10.6%, which is slightly larger than the 10% composition difference too. Out of three photon energy combination schemes, 6 MeV – 6.5 MeV – 11 MeV has the highest coefficient of determination for all three nuclides and the smallest deviation of below 10% composition difference. Random sampling with normal distribution was performed on the loss to photofission particles from MCNP with 200 sets for each 10 cases on the 6 MeV – 7 MeV – 11 MeV photon energy combination to study the stochastic errors. The isotopic compositions were calculated with the same numerical method, and the difference between the estimated and actual compositions that resulted were fitted with R. The fitting results show good agreement within 91.5% confidence intervals.