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
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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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Nuclear Science and Engineering
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May 2025
Latest News
Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
K. Shure
Nuclear Science and Engineering | Volume 19 | Number 3 | July 1964 | Pages 310-320
Technical Paper | doi.org/10.13182/NSE64-A20964
Articles are hosted by Taylor and Francis Online.
Neutron penetration in water and in iron/water shields has been calculated using a P-3 multigroup program. The thermal-neutron flux from a point fission source in water obtained from calculation and experiment agree to within 18% in the region between 15 and 140 cm, covering more than 9 decades of attenuation. The calculated neutron spectrum compares favorably in shape and magnitude with moments-method results out to 120 cm of water. The observed variations of the thermal-neutron flux in an iron/water shield are predicted by the P-3 program. Some of the differences between experiment and the predicted thermal flux within a thick iron region are due to the single-energy-group treatment in the calculations. Uncertainties in the high-energy cross sections for iron are of sufficient magnitude to account for differences between calculation and experiment noted in the water region following iron.
