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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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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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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Nuclear supply chain innovation and collaboration: Keeping the nuclear supply chain viable through change
The next nuclear renaissance may be upon us, but with it comes a perfect storm. The industry is unprepared for a surge in demand for goods and services from both the existing light water fleet and the next generation of reactors. We are currently teetering on the edge of severe supply chain issues, but if the nuclear industry can understand the sources of our challenges, we can mitigate them.
S. B. Gunst, J. C. Connor, D. E. Conway
Nuclear Science and Engineering | Volume 58 | Number 4 | December 1975 | Pages 387-413
Technical Paper | doi.org/10.13182/NSE75-A26795
Articles are hosted by Taylor and Francis Online.
Samples of 233U and of natural thorium have been irradiated in high neutron-flux facilities, in both soft and hard neutron spectra, and for both short and long exposure times. Included are exposures resulting in depletions of more than 90% of the 233U in the fissile material and burnups of more than 30 000 MWd/MT in the fertile material. Postirradiation mass analyses of the total and the isotopic uranium, of 137Cs, and of the neodymium isotopes generally agree within a few percent with corresponding calculations based on measured exposure histories. Reactivity measurements between irradiation cycles provide experimental results for the fissile content and fission-product poisoning as functions of both irradiation and cooling time. Corresponding results obtained from calculated concentrations agree with measurements to ∼1% for the fissile content and 3% for the effective one-group fission-product poison cross section. However, fission-product poison cross sections in two energy groups (thermal and epithermal) exhibit differences between measurement and calculation that are believed to be attributable to a lack of adequate information on important fission products in the literature. Experimental results for transient absorbers in irradiated 233U give at least 20 000 b for the neutron absorption resonance integral of 149Pm. This is a factor of 15 higher than that obtained by a 1/v extrapolation of the thermal cross section. For transient 135Xe, the measured absorption is 7.5% higher than that calculated using ENDF/B-IV data. Information is also provided concerning such matters as fission yields and neutron absorption of neodymium isotopes, the existence of significant transient fission-product poisons other than 135Xe and 149Sm, and the shielding of 233U by 232Th. Such shielding suggests the need for a change in the energy dependence of the 232Th thermal-neutron cross section.