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Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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.
J. F. Perkins, R. W. King
Nuclear Science and Engineering | Volume 3 | Number 6 | June 1958 | Pages 726-746
Technical Paper | doi.org/10.13182/NSE58-A25507
Articles are hosted by Taylor and Francis Online.
The total disintegration rates, rates of beta- and gamma-energy release, and gamma-ray energy spectrum, are calculated for fission products due to thermal neutron fission of U235. Information on decay schemes was largely obtained from the compilations of the Nuclear Data Group of the National Research Council to July, 1957. Total fission yields are from Katcoff and from Steinberg and Glendenin. Nuclear charge distributions are taken from Pappas’ work, which includes the effect of closed shells. Reactor operating times of 1, 10, 100, and 1000 hours are treated, and the results plotted for decay times ranging from 102 to 108 seconds. In addition, results for instantaneous operation are compared to other calculations and measurements. The present results fall below Way and Wigner’s predictions of both disintegration rate and total energy release over the entire range of decay times, though they agree satisfactorily with the Way-Wigner rule-of-thumb expressions. The present results are in very good agreement with experimental measurements. The gamma spectrum is found to vary considerably with decay time but to be only a weak function of reactor operating time. The total beta and antineutrino energies per fission are found to be 7.6 ± 0.5 and 10.0 ± 0.7, respectively.
