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Division Spotlight
Fuel Cycle & Waste Management
Devoted to all aspects of the nuclear fuel cycle including waste management, worldwide. Division specific areas of interest and involvement include uranium conversion and enrichment; fuel fabrication, management (in-core and ex-core) and recycle; transportation; safeguards; high-level, low-level and mixed waste management and disposal; public policy and program management; decontamination and decommissioning environmental restoration; and excess weapons materials disposition.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.
S. Bourganel, O. Petit, C. M. Diop
Nuclear Technology | Volume 184 | Number 1 | October 2013 | Pages 29-41
Technical Paper | Neutron Transport and Shielding | doi.org/10.13182/NT13-A19866
Articles are hosted by Taylor and Francis Online.
The Électricité de France nuclear park consists of 58 pressurized water nuclear reactors. To ensure their good performance and safety, ex-core neutron shielding studies are regularly performed. For example, neutron flux calculations in ex-core ionization chambers and pressure vessel neutron fluence studies are carried out. In the first case, ex-core ionization chambers are neutron detectors located in the reactor pit, around the reactor vessel. They are dedicated to reactor operation and core protection. In the second case, the calculation of the fast fluence (for energy >1 MeV) in the pressure vessel is used to determine its fracture toughness and integrity. To improve the fluence computations, new efficient parametric methods are under development. For these two problems, Monte Carlo transport codes such as TRIPOLI-4® allow us to perform simulations in realistic complex three-dimensional geometries and to produce reference results.The aim of the present paper is to present together the theoretical background of our approach based on the continuous-energy Green's functions computation and storage to perform both vessel neutron fluence and ex-core chamber responses. The normalized source contribution or importance factor formalism using Green's functions computation is also described, with its associated statistical uncertainty calculation. Application examples to realistic nuclear plant configurations are given.