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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
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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NRC cuts fees by 50 percent for advanced reactor applicants
The Nuclear Regulatory Commission has announced it has amended regulations for the licensing, inspection, special projects, and annual fees it will charge applicants and licensees for fiscal year 2025.
K. F. Flynn, L. E. Glendenin, E. P. Steinberg
Nuclear Science and Engineering | Volume 22 | Number 4 | August 1965 | Pages 416-419
Technical Paper | doi.org/10.13182/NSE65-A20627
Articles are hosted by Taylor and Francis Online.
Half-lives have been measured by direct decay for 18 radionuclides. The method of least squares was used to obtain the best straight-line fit to the data. The observed half-lives are 87.9 ± 0.3 d for S35, 52.7 ± 0.5 d for Sr89, 13.6 ± 0.3 y for Nb93m, 35.8 ± 0.5 d for Nb95, 65.5 ± 0.2 d for Zr95, 39.5 ± 0.3 d for Ru103, 368.0 ± 1.8 d for Ru106, 13.6 ± 0.2 y for Cd113, 76.3 ± 6.6 y for Sn121, 2.71 ± 0.02 y for Sb125, 1.99 ± 0.02 y for Cs134, 283.8 ± 0.6 d for Ce144, 2.60 ± 0.02 y for Pm147, 87 ± 9 y for Sm151, 134.2 ± 0.8 d for Tm170, 700± 5 d for Tm171, 3.68 ± 0.05 y for Tl204, and 164.4 ± 0.4 d for Cm242. These data are compared with current literature values, and average values of the existing determinations are given.
