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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
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.
R. H. Karcher
Nuclear Science and Engineering | Volume 27 | Number 2 | February 1967 | Pages 367-387
Technical Paper | doi.org/10.13182/NSE67-A18276
Articles are hosted by Taylor and Francis Online.
The transport of neutrons from a point source of simulated weapons radiation in infinite air is calculated. Weapons neutron spectra are simulated using a mixed source composed of a chopped fission spectrum with most of the neutrons below 0.4 MeV deleted, and an equivalent number distributed uniformly in the 12- to 16-MeV range. The results obtained are generally conservative, from a shielding standpoint, for most nuclear devices. The method of track length stretching is used to improve the efficiency of the Monte Carlo analysis for deep penetration calculations. Well-converged fast-neutron flux and dose data are obtained for penetration distances of about 400 g/cm2 (approximately 2 miles in sea-level air at 68°F). Energy spectra and angular distributions are calculated also; however, the convergence is less satisfactory in this case. It is found that the inelastic and capture gamma sources resulting from neutron interaction in air are of extremely low intensity and are probably negligible for most shielding applications. Integral and differential neutron air-transport data are tabulated as a function of penetration distance to facilitate their use in shielding calculations.