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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.
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Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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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.
N. J. Pattenden
Nuclear Science and Engineering | Volume 17 | Number 3 | November 1963 | Pages 371-380
Technical Paper | doi.org/10.13182/NSE63-A17385
Articles are hosted by Taylor and Francis Online.
The ORNL chopper has been used to measure the neutron total cross sections of samples of fission product samarium and iodine in the thermal and resonance energy regions. At 2200 meters/sec, the total cross section of Sm151 was found to be (15000 ± 1800) barns, and the absorption cross section of I129 (28.0 ± 2) barns. The variation of cross section of Sm151 with energy in the thermal region was found to be strongly affected by a bound level, but in the case of I129 the absorption cross section could be described by a “1/V” dependence. In the higher energy region, resonance parameters were obtained for Sm151, I127, and I129 by area analysis of the observed transmission dips. In addition, a shape analysis method was used for the lower energy resonances in Sm151. The following values for the level spacings and strength functions (per spin state), and resonance absorption integrals were obtained:
