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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.
Mitchell R. Swartz
Fusion Science and Technology | Volume 31 | Number 2 | March 1997 | Pages 228-236
Technical Paper | Nuclear Reaction in Solid | doi.org/10.13182/FST97-A30825
Articles are hosted by Taylor and Francis Online.
An explanation is given for the anomalous branching ratio in solids based on Boson-cooperative removal of the 4He* energy prior to decay by two-body fission. Facilitated by isospin restrictions that limit conventional pathways, the excess heat is driven by the reconfiguration to the more tightly bound 4He ground state. A temperature rise occurs as well-mixed acoustical and optical phonons are unable to carry off all the local momentum and excess energy of the reactions. Four-vector analysis indicates conservation of energy, which suggests the use of a fusion quantum of energy delivered to the lattice's phonon cloud: a phuson. Special relativistic considerations indicate that the phonon cloud subtends ∼450 to 800 unit cells and can couple with de-excitation times >0.1 fs. Thus, commensurate levels of neutrons and gammas are not required because of unique isospin and energy restrictions that facilitate the alternate Bose-cooperative pathway leading from the excited state.