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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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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.
Robert E. Uhrig
Nuclear Science and Engineering | Volume 5 | Number 2 | February 1959 | Pages 120-126
Technical Paper | doi.org/10.13182/NSE59-A25564
Articles are hosted by Taylor and Francis Online.
The Iowa State College subcritical assembly is a natural uranium-graphite pile constructed as a teaching tool to illustrate the principles of nuclear physics and engineering and as a facility for graduate thesis research in nuclear engineering. The determination of the basic operating characteristics of this assembly is described and discussed. The material buckling as determined from flux measurements was the parameter used in comparing the results. Tests were conducted for the 6 in., in., and 12 in. lattice arrangements and for all uranium removed. Tests were made with air and water in the coolant annuli surrounding the uranium slugs. Bucklings were calculated using the elementary theory of Murray (in which all extraneous materials are treated as poisons) and the method of Volkoff and Rumsey (in which the moderating effect of the water and the shielding effects of the various materials are considered) for the three lattice arrangements, and they are compared with the experimental results. The position of the neutron sources in the source compartment and the presence of water around the sources were found to affect the measured value of material buckling.
