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Conference 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!
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Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Roger Lee Ritenour, Roger A. Rydin, Robert U. Mulder
Nuclear Science and Engineering | Volume 106 | Number 4 | December 1990 | Pages 457-470
Technical Paper | doi.org/10.13182/NSE90-A23770
Articles are hosted by Taylor and Francis Online.
A variety of scattering model approximations have been devised and evaluated. One such scattering model, designated the balanced single collision thermalization (BSCT) approximation, has proven to be very effective. It assumes that neutrons attain a thermalized distribution with only a single collision within the moderating material, independent of incident energy. This approximation leads to separability of the incident and outscattering energies and to significant simplification of the neutron scattering kernel for thermalization problems. The BSCT approximation is particularly useful in thermalization problems involving cold neutron sources, for which it yields flux predictions to within a few percent of exact solutions of theoretical problems. The BSCT approximation also predicts cold neutron fractions to within 10% of measured values for a cold neutron thermalization experiment done at Argonne National Laboratory.