ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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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.
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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May 2025
Latest News
Ariz. governor vetoes “fast track” bill for nuclear
Gov. Katie Hobbs put the brakes on legislation that would have eliminated some of Arizona’s regulations and oversight of small modular reactors, technology that is largely under consideration by data centers and heavy industrial power users.
W. P. Poenitz
Nuclear Science and Engineering | Volume 47 | Number 2 | February 1972 | Pages 228-230
Technical Note | doi.org/10.13182/NSE72-A22401
Articles are hosted by Taylor and Francis Online.
The ratio of the fission cross sections of 239Pu to that of 235U has been measured at 30 keV and from 0.5 to 5.4 MeV. A value of 0.796 ± 0.020 has been obtained at 30 keV. None of the structure reported recently by Savin et al. could be found in the MeV range in the present measurements.