ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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!
Latest Magazine Issues
Jun 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
July 2025
Fusion Science and Technology
Latest News
Supreme Court rules against Texas in interim storage case
The Supreme Court voted 6–3 against Texas and a group of landowners today in a case involving the Nuclear Regulatory Commission’s licensing of a consolidated interim storage facility for spent nuclear fuel, reversing a decision by the 5th Circuit Court of Appeals to grant the state and landowners Fasken Land and Minerals (Fasken) standing to challenge the license.
Tatjana Jevremovic, Yoshiaki Oka, Sei-Ichi Koshizuka
Nuclear Technology | Volume 114 | Number 3 | June 1996 | Pages 273-284
Technical Paper | Fission Reactor | doi.org/10.13182/NT96-A35232
Articles are hosted by Taylor and Francis Online.
The core design of a fast converter reactor adopting enriched UO2 fuel is studied for maximizing the power rating of the direct-cycle, supercritical water-cooled fast reactor with the same reactor pressure vessel as the breeder and mixed-oxide (MOX) fueled converter. The coolant void reactivity is kept negative by placing thin zirconium-hydride layers in the blanket fuel assemblies facing the driver fuels, as in our fast breeder reactor design. Compared with the fast converter adopting MOX fuel, the electric power output is increased 11%, from 1444 to 1625 MW(electric). It is attained by the reduced blanket fuel fraction for keeping negative reactivity at coolant voiding. The positive reactivity at flooding the core is much larger than that of the MOX core, but it can be managed by the control rod system. The conversion ratio, the surviving ratio, is 0.85, reduced 0.1 from that of the MOX converter. The enrichment of UO2fuel reaches 16.9%. The specific fissile inventory is the highest, compared with the MOX-fueled converter and breeder due to the lower fission cross sections of 235U. The cores of the supercritical water-cooled reactors are radially heterogeneous. The decoupling problem is, however, much smaller than that of the liquid-metal fast breeder reactor due to the smaller core diameter. The hydrogen loss from the zirconium hydrides at steady state and accidental conditions does not impose a problem.