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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
Dragonfly, a Pu-fueled drone heading to Titan, gets key NASA approval
Curiosity landed on Mars sporting a radioisotope thermoelectric generator (RTG) in 2012, and a second NASA rover, Perseverance, landed in 2021. Both are still rolling across the red planet in the name of science. Another exploratory craft with a similar plutonium-238–fueled RTG but a very different mission—to fly between multiple test sites on Titan, Saturn’s largest moon—recently got one step closer to deployment.
On April 25, NASA and the Johns Hopkins University Applied Physics Laboratory (APL) announced that the Dragonfly mission to Saturn’s icy moon passed its critical design review. “Passing this mission milestone means that Dragonfly’s mission design, fabrication, integration, and test plans are all approved, and the mission can now turn its attention to the construction of the spacecraft itself,” according to NASA.
M. Z. Youssef, M. A. Abdou, A. Kumar, Li Zhang, K. Kosako, Y. Oyama, F. Maekawa, Y. Ikeda, C. Konno, H. Maekawa
Fusion Science and Technology | Volume 28 | Number 2 | September 1995 | Pages 320-346
Technical Paper | Fusion Neutronics Integral Experiments — Part II / Blanket Engineering | doi.org/10.13182/FST95-A30649
Articles are hosted by Taylor and Francis Online.
Experimental simulation to a line source has been realized at the Japan Atomic Energy Research Institute (JAERI) Fusion Neutronics Source within the U.S. Department of Energy/JAERI collaborative program on fusion neutronics. This simulation, achieved by cyclic movement of an annular Li2O test assembly relative to a stationary point source, was a step forward in better simulation of the energy and angular distributions of the incident neutron source found in tokamak plasmas. Thus, compared with other experiments previously performed with a stationary point source, the uncertainties (that are system dependent) in calculating important neutronics parameters, such as tritium production rate (TPR), will be more representative of those anticipated in a fusion reactor. The rectangular annular assembly used is 1.3 × 1.3 m and 2.04 m long with a square cavity of 0.42 × 0.42 m cross section where the simulated line source (2 m long) is located axially at the center. To characterize the incident neutron source, flux mapping with foil activation measurements was performed in the axial direction (Z = −100 cm to Z = 100 cm) at the front surface of the assembly in the cavity with the annular blanket in place, and comparison was made to the bare line-source case (without annular blanket). Three phases of experiments were performed. In Phase-IIIA, a 1.5-cm-thick stainless steel first wall was used. An additional 2.45-cm-thick carbon layer was added in Phase-IIIB, and a large opening (42.55 × 37.6 cm) was made at one side at the center of the annular assembly in Phase-IIIC. Calculations were performed independently by the United States and JAERI for many measured items that included TPR from 6Li(T6), 7Li(T7), in-system spectrum measurements, and various activation measurements. In this paper, the calculated-to-measured values for the aforementioned measured items are given, as obtained separately by the United States and JAERI. In addition, the mean value of the prediction uncertainties of the local and line-integrated TPR and the associated standard deviations are given based on the calculational and experimental results obtained in all the experiments.
