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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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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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.
Eugene E. Drucker, William D. Wallace
Nuclear Science and Engineering | Volume 3 | Number 3 | March 1958 | Pages 215-231
Technical Paper | doi.org/10.13182/NSE58-A25463
Articles are hosted by Taylor and Francis Online.
The applicability of a power-range instrument based on coolant gamma activity is discussed, indicating considerable merit for certain systems, but with some limitations. A general equation is presented for equilibrium coolant activity at reactor discharge. The effect of changing flow rate at fixed power is shown to influence detector reading. The effect of time lag between reactor outlet and detector is shown to introduce error, but that optimum location of the detector will minimize the total detector error. Transient response to step power and to step flow changes are evaluated. Analysis is applied to a water-cooled system and experimental data shown to verify predicted behavior. Effects of coolant impurities are discussed.
