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Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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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.
Y. S. Rana, S. B. Degweker
Nuclear Science and Engineering | Volume 162 | Number 2 | June 2009 | Pages 117-133
Technical Papers | doi.org/10.13182/NSE08-13
Articles are hosted by Taylor and Francis Online.
In our earlier papers, we developed a theory of reactor noise for accelerator-driven systems (ADSs). It was shown that reactor noise in ADSs is different from that in critical or radioactive source-driven subcritical systems because of the periodically pulsed source and its non-Poisson character. Various noise descriptors, such as Rossi alpha, Feynman alpha (or variance to mean), power spectral density, and cross-power spectral density, were derived, for a periodically pulsed source, including correlation between different pulses and finite pulses of different shapes. Throughout the work we restricted ourselves to the case of prompt neutrons only. In the present paper, we extend the theory to the delayed neutron case. Feynman-alpha and Rossi-alpha formulas are derived by considering the source to be a periodically pulsed non-Poisson source, without correlations between different pulses. Each pulse is assumed to be a delta function. The calculations are carried out in the time domain that leads to closed-form expressions for these descriptors.