ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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.
E. Starr, H. Honeck, J. DeVilliers†
Nuclear Science and Engineering | Volume 18 | Number 2 | February 1964 | Pages 230-235
Technical Paper | doi.org/10.13182/NSE64-A18322
Articles are hosted by Taylor and Francis Online.
This describes an experimental technique to determine the average velocity of the thermal-neutron spectrum as a function of time in a pulsed-neutron experiment. The measurement of the average velocity as a function of time is used to determine two parameters: the time necessary to establish an asymptotic spectrum, and the average velocity of the asymptotic spectrum. The variation in the asymptotic average velocity with material buckling is described by a “spectral-shift coefficient” which is related to the diffusion-cooling coefficient. It was found necessary to wait 2 milliseconds for the establishment of an equilibrium spectrum in graphite, and 0.6 milliseconds in heavy water, and that these values are insensitive to the geometric buckling. Values of the spectral-shift coefficient are given and compared with theoretical estimates.
