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Division Spotlight
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.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
W. Krappel, H. Seufert, D. Stegemann
Nuclear Technology | Volume 12 | Number 2 | October 1971 | Pages 226-234
Technical Paper | Analysis | doi.org/10.13182/NT71-A31030
Articles are hosted by Taylor and Francis Online.
The 140Ba cumulative yield of irradiated uranium has been determined absolutely by a nondestructive method. Thin uranium foils are irradiated in the fast thermal zero-power reactor STARK. To avoid radiochemical separation, the 1596.5-keV gamma activity of 140La, the daughter nucleus of 140Ba, is measured with a high resolution (2.6 keV fwhm) Ge (Li) detector. From this 140La activity the absolute 140Ba yield is evaluated from the corresponding absolute fission rate and. the detector efficiency known for the 1596.5-keV photopeak. The uranium fission rate in the foil is normalized to the absolute fission rate measured with a calibrated parallel-plate chamber. Calibration of the gamma spectrometer is performed with activated thin La2O3 foils whose absolute activities are determined by 2π beta counting. The 140Ba cumulative yield data obtained are 6.29 ± 0.14% for 235 U thermal neutron fission and 6.10 ± 0.15(%) and 6.34 ± 0.41(%) for fast neutron fission of 235U and 238U, respectively. They are in good agreement (within ±1%) with the values reported to date.
