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
Materials Science & Technology
The objectives of MSTD are: promote the advancement of materials science in Nuclear Science Technology; support the multidisciplines which constitute it; encourage research by providing a forum for the presentation, exchange, and documentation of relevant information; promote the interaction and communication among its members; and recognize and reward its members for significant contributions to the field of materials science in nuclear technology.
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
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.
D. Shalitin, J. J. Wagschal, Y. Yeivin
Nuclear Science and Engineering | Volume 68 | Number 3 | December 1978 | Pages 243-248
Technical Paper | doi.org/10.13182/NSE78-A27303
Articles are hosted by Taylor and Francis Online.
Conditions for the reduction of the time-independent neutron transport equation to an energy-independent (one-group) equation are discussed. It is shown that a meaningful reduction is equivalent to angular flux separability into a product of an energy spectrum and a spatial and angular function. It is proven that such a separability in a finite system is possible if and only if the total cross section is energy independent, provided some auxiliary conditions are met. The physical situations in which these conditions are satisfied and the similarity to the so-called first fundamental theorem of reactor theory are discussed.
