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
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.
Fred Holzer, Marshall F. Crouch
Nuclear Science and Engineering | Volume 6 | Number 6 | December 1959 | Pages 545-553
doi.org/10.13182/NSE59-A15517
Articles are hosted by Taylor and Francis Online.
The effects of leakage, detector and source perturbation, and the presence of higher modes in the neutron density distribution on a determination of the mean lifetime of thermal neutrons in water are discussed. The methods used in several recent experiments to minimize these sources of error are analyzed, with particular attention paid to the problem of suppressing the higher modes of the neutron density distribution. The effect of moderator dimensions is presented in terms of mode suppression factors for three characteristic moderator sizes. Finally, the mathematical analysis for a proposed large-geometry, high precision mean lifetime experiment is presented, in which the neutron distribution is calculated as a solution to an eigenvalue problem with variable boundary conditions. Three approximations are presented which allow the counter perturbation to be calculated and the mode content controlled.