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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
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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
Senate committee hears from energy secretary nominee Chris Wright
Wright
Chris Wright, president-elect Trump’s pick to lead the U.S. Department of Energy, spent hours today fielding questions from members of the U.S. Senate’s committee on Energy and Natural Resources.
During the hearing, Wright—who’s spent most of his career in fossil fuels—made comments in support of nuclear energy and efforts to expand domestic generation in the near future. Asked what actions he would take as energy secretary to improve the development and deployment of SMRs, Wright said: “It’s a big challenge, and I’m new to government, so I can’t list off the five levers I can pull. But (I’ve been in discussions) about how to make it easier to research, to invest, to build things. The DOE has land at some of its facilities that can be helpful in this regard.”
J. T. Mihalczo, T. E. Valentine
Nuclear Science and Engineering | Volume 121 | Number 2 | October 1995 | Pages 286-300
Technical Paper | doi.org/10.13182/NSE95-A28565
Articles are hosted by Taylor and Francis Online.
The 252Cf-source-driven noise analysis method has been used in measurements for subcritical configurations of fissile systems for a variety of applications, including a dynamic measurement that was the first step in applying this method to monitor nuclear fuel processing plants. Previous measurements have shown large changes in noise-measured parameters such as the coherences and ratio of spectral densities for small changes in the measured configuration of fissile material, for small changes in k, or for changes in other system variables. Direct calculation of the experimental observables by the Monte Carlo method allows the benchmarking of calculational methods and cross sections with a higher sensitivity to changes than calculations of the neutron multiplication factor itself. Measurements and sensitivity studies with the KENO-NR Monte Carlo neutron transport code showed that this measurement method has the potential to monitor many dynamic situations in processing plants such as in casting facilities, in a continuous dissolver, or in batch dissolvers either to be used as a signature to verify that various processes are occurring in a repeatable or bounded way or to obtain the neutron multiplication factor k. This verification of normal operation would be by comparing noise analysis signatures for the process with reference signatures. A Abnormal operation could be ascertained if the signature deviates by some specified amount from the reference signatures from normal operation. The deviations from normal could be specified by measurements or by Monte Carlo neutron transport theory methods directly calculating the measured parameters for the processing plant applications. Measurements with enriched uranyl nitrate solutions are presented as an example to demonstrate the high measured sensitivity of noise-measured parameters. To evaluate this high sensitivity, KENO-NR was used to investigate changes in the noise-measured parameters to variation in fissile system parameters using neutron transport calculations for three aqueous solutions, uranyl nitrate, uranyl fluoride, and plutonium nitrate, and also for an array of light water reactor spent fuel. This high sensitivity has also allowed this measurement method to be used to identify nuclear weapons and/or weapons components in shipping containers by comparing with reference signatures obtained from measurements or calculations and for nondestructive assay of special nuclear materials.
