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Division Spotlight
Education, Training & Workforce Development
The Education, Training & Workforce Development Division provides communication among the academic, industrial, and governmental communities through the exchange of views and information on matters related to education, training and workforce development in nuclear and radiological science, engineering, and technology. Industry leaders, education and training professionals, and interested students work together through Society-sponsored meetings and publications, to enrich their professional development, to educate the general public, and to advance nuclear and radiological science and engineering.
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.
Alan Jacobs
Nuclear Science and Engineering | Volume 6 | Number 2 | August 1959 | Pages 147-151
Technical Paper | doi.org/10.13182/NSE59-A25645
Articles are hosted by Taylor and Francis Online.
A two-group albedo theory is developed which seems to be valid for the calculation of temperature coefficients of nuclear reactors characterized by the PSR. Measurements of over-all coefficient for the PSR are in qualitative agreement with results calculated by the theory. Analysis under the present theory singles out the temperature variation of the ratio of the age to the thermal neutron diffusion length of the reflector as the primary contributor to a low temperature positive coefficient effect. The advantage of representing the criticality factor, k, by the two-group albedo theory is well illustrated by the endeavor of calculating the temperature coefficient. Under normal two-group multiregion treatment the criticality factor never explicitly appears and therefore it is impossible to obtain an explicit form of the variation of k with system parameters. The dissection of the nonleakage probability in the present theory is not unique, but it does lead to easy physical interpretation.
