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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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Latest News
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.
Jingshang Zhang
Nuclear Science and Engineering | Volume 114 | Number 1 | May 1993 | Pages 55-63
Technical Paper | doi.org/10.13182/NSE93-3
Articles are hosted by Taylor and Francis Online.
The master equation theory of precompound and compound nuclear reactions has been generalized to include the conservation of angular momentum and parity. Based on this improved semi-classical theory, the UNF code has been developed as a tool for calculating nucleon-induced reaction cross sections and double-differential cross sections at incident neutron energies below 20 MeV. It is demonstrated that the code contains the Hauser-Feshbach model and the exciton models as the limiting cases. The unified treatment of equilibrium and pre-equilibrium reaction processes includes the introduction of composite particle formation factors in calculations of pickup-type composite particle emissions. A method to calculate the double-differential cross sections for all kinds of particles is proposed based on the leading particle model.
