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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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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.
R. J. Jiacoletti, W. K. Brown, H. G. Olson
Nuclear Science and Engineering | Volume 48 | Number 4 | August 1972 | Pages 412-419
Technical Paper | doi.org/10.13182/NSE72-A22509
Articles are hosted by Taylor and Francis Online.
The 237Np(n,f) cross section has been measured relative to the 235U(n,f) cross section from 20 eV to 7 MeV, including the range where no data previously existed (4 to 24 keV). Energies of the source neutrons from the Physics 8 underground nuclear explosion were determined by measuring the time-of-flight from the source to the neptunium target foil. The current signals produced in solid-state detectors by fission fragments were photographically recorded and converted to cross sections using the neutron flux measured with 235U(n,f)and 6Li(w,α)T reactions. Subthreshold resonances were observed in the 237Np(n,f) cross section. The maximum value of the cross section observed just above threshold is 1.9 b at 2.26 MeV. A comparison of results with some previously reported values is presented.Present address: University of Wyoming, Laramie, Wyoming 82070.
