ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
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.
M. T. Andrews, J. T. Goorley, E. C. Corcoran, D. G. Kelly
Nuclear Technology | Volume 187 | Number 3 | September 2014 | Pages 235-242
Technical Paper | Fission Reactors | doi.org/10.13182/NT13-72
Articles are hosted by Taylor and Francis Online.
Study of the magnitude and temporal behavior of delayed neutrons (DNs) enables the identification of fissile isotopes and a determination of their relative quantities. Thus, the ability to model accurately these neutrons and the methods of their detection is of relevance to nuclear forensics and counterterrorism. The capability of MCNP6 to model these emissions was examined and compared to measurements of the DNs produced by 233U, 235U, and 239Pu after neutron-induced fission. Fissile samples were irradiated in a SLOWPOKE-2 research reactor for 60 s and were then conveyed via pneumatic tubing to an array of six 3He detectors embedded in a paraffin moderator. Several MCNP6 input files were created to reproduce irradiation conditions, temporal DN emission, and the detection arrangement. Nuclear reactions and other effects within the 3He detectors were reproduced by MCNP6, and detection efficiencies of this modeled arrangement determined by MCNP6 were in agreement with experimental measurements. Finally, the library and model DN emission options in the MCNP6v1 release were evaluated and compared to the measured magnitudes and temporal behavior of 233U, 235U, and 239Pu. Significant discrepancies observed between the DN model option and measurements for count times >100 s are discussed.
