ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Nuclear Nonproliferation Policy
The mission of the Nuclear Nonproliferation Policy Division (NNPD) is to promote the peaceful use of nuclear technology while simultaneously preventing the diversion and misuse of nuclear material and technology through appropriate safeguards and security, and promotion of nuclear nonproliferation policies. To achieve this mission, the objectives of the NNPD are to: Promote policy that discourages the proliferation of nuclear technology and material to inappropriate entities. Provide information to ANS members, the technical community at large, opinion leaders, and decision makers to improve their understanding of nuclear nonproliferation issues. Become a recognized technical resource on nuclear nonproliferation, safeguards, and security issues. Serve as the integration and coordination body for nuclear nonproliferation activities for the ANS. Work cooperatively with other ANS divisions to achieve these objective nonproliferation policies.
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
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.
Robert T. McGrath, C. Christopher Klepper, Taner Uckan, Peter K. Mioduszewski
Fusion Science and Technology | Volume 14 | Number 2 | September 1988 | Pages 339-353
Technical Paper | Divertor/Limiter System | doi.org/10.13182/FST88-A20266
Articles are hosted by Taylor and Francis Online.
The relative positioning of the limiter modules on Tore Supra is investigated with the objective of optimizing the overall performance of the system and the operational flexibility of the experiment. Limiter system performance is optimized by simultaneously maximizing the power handling and particle exhaust capabilities. This must be accomplished for the entire range of edge q values anticipated on Tore Supra. In addition, it is desirable to independently maximize power handling, to allow operation at very high levels of plasma auxiliary heating, or particle exhaust, to allow operation at high pellet injection fueling rates. The relative merit of one configuration with respect to another is determined using a diffusion model for charged-particle radial transport coupled with a detailed three-dimensional mapping of the magnetic field structure in the edge plasma region. To implement the model, assumptions must be made about the edge plasma conditions including the rate of charged-particle diffusion. These assumptions affect the absolute values of the power handling and particle exhaust capabilities of the system but do not affect the merit of one configuration relative to another. Working within the constraints imposed by the availability of ports on Tore Supra, the best limiter configuration for a system of seven modular limiters is identified. The performance to be expected for this optimized configuration for various modes of Tore Supra operation is reported. Very long flux tubes must be avoided if the limiter system is to operate near its full design capacity of 8.0 MW. For the assumed edge conditions, Böhm diffusion with a plasma temperature of 150 eV at the last closed flux surf ace, the configuration identified can exhaust between 17 and 21 Torr · ℓ/s while removing 5 to 8 MW of power incident on the limiter surfaces. Operational modes that pump as much as 26 Torr · ℓ/s are also possible if incident power levels are reduced to 4.0 MW. Operation with large amounts of auxiliary heating, in excess of 15 MW, is also possible by power sharing with the actively cooled inner bumper limiter. In this situation, particle pumping rates may be as low as 9 Torr · ℓ/s.
