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
2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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Nuclear Science and Engineering
October 2024
Nuclear Technology
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August 2024
Latest News
New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
Sten-Örjan Lindahl
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 475-478
Technical Note | doi.org/10.13182/NSE74-A23378
Articles are hosted by Taylor and Francis Online.
Using the multigroup diffusion equation, a reciprocity relation is established for an arbitrarily shaped body. This relation expresses the flux caused by a source inside the body in terms of the flux resulting from an incident current on that body. In the multigroup case for one-dimensional bodies with flat sources and in the one-group case for rectangular two-dimensional bodies with an arbitrary source, practical formulas are derived from this relation. These give the leakage from a body in terms of its reflection and transmission properties. An advantage of the use of this reciprocity relation is the improved computational efficiency in response matrix calculations.