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Division Spotlight
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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!
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Nuclear Science and Engineering
March 2025
Nuclear Technology
Fusion Science and Technology
April 2025
Latest News
Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
P. Kafalas, M. Levenson, C. M. Stevens
Nuclear Science and Engineering | Volume 2 | Number 5 | September 1957 | Pages 657-663
Technical Paper | doi.org/10.13182/NSE57-A25432
Articles are hosted by Taylor and Francis Online.
The variation of alpha, the ratio σc/σf, has been determined for U235 and Pu239 as a function of position in EBR. Samples of U235 and Pu239 were exposed in the core, inner blanket, and outer blanket; the samples were analyzed radiochemically to determine the fraction fissioned and mass spectrometrically to determine the fraction which had undergone the capture process. The vertical and horizontal patterns of capture and fission probability have been determined. The variation of η in the reactor has been plotted, assuming that remains constant.