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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.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
Investment bill would provide funding options for energy projects
Coons
Moran
The bipartisan Financing Our Futures Act, which expands certain financing tools to all types of energy resources and infrastructure projects, was reintroduced to the U.S. Senate on February 20 by Sens. Jerry Moran (R., Kan.) and Chris Coons (D., Del.).
Via amendment to the Internal Revenue Code, the legislation would allow advanced nuclear energy projects to form as master limited partnerships (MLPs), a tax structure currently available only to traditional energy projects.
An MLP is a business structure that is taxed as a partnership but the ownership interests of which are traded like corporate stock on a market. Until the Internal Revenue Code is amended, MLPs will continue to be available only to investors in energy portfolios for oil, natural gas, coal extraction, and pipeline projects that derive at least 90 percent of their income from these sources. This change would take effect on January 1, 2026.
B. M. Durst, S. R. Bierman, E. D. Clayton, J. F. Mincey
Nuclear Technology | Volume 48 | Number 2 | April 1980 | Pages 128-149
Technical Paper | Fuel | doi.org/10.13182/NT80-A32460
Articles are hosted by Taylor and Francis Online.
A series of experiments was performed at the Batelle-Pacific Northwest Laboratories on water-flooded arrays of Fast Test Reactor fuel elements (PUO2-UO2) intermixed with solid neutron absorbers. The objective of these experiments was to provide reliable experiment data that could be used to benchmark computer codes and calculational schemes commonly used in criticality analysis of such systems. The neutron absorbers used were cadmium and Boral plates and gadolinium cylindrical rods. Critical array sizes were determined for square lattice pitches ranging from 9.7 to 24.9 mm, corresponding to water-to-fuel volume ratios of 3.5 to ∼31 (hydrogen atom to fissile atom ratios of 58 to 473). For both systems, poisoned and unpoisoned, the minimum number of rods required for criticality occurred at a lattice pitch of ∼20.5 mm, which also corresponds to a water-to-fuel volume ratio of 20.5. The smallest critical number of rods for the unpoisoned array was 157. Boral was the most effective absorber, irrespective of degree of moderation or its position in the assembly. However, all three absorbers varied in degree of effectiveness with moderation.
